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55 Tony
08-21-2018, 03:22 PM
While I have the tranny out, I'm thinking of buying a higher stall converter but I'm really curious how it will act on the highway, like how much slippage it will have on the street. The one I'm looking at is a Summit brand https://www.summitracing.com/parts/sum-g2698

What is with the "anti ballooning plate"? I noticed at jegs their similar converter says it's not recommended for BB's to choose from their heavy duty ones.

Rick_L
08-21-2018, 04:44 PM
I don't see any clues in your Summit link as to what the stall speed on this converter would be. What stall speed do you have now and what stall speed do you think you want?

When you stall the converter, internal pressure tries to expand it. It can't expand to a bigger diameter, but it can expand lengthwise, especially on the front (flywheel) end. An anti-ballooning plate stiffens the front and keeps this from happening. If you are running a transbrake this becomes more important, but it could be needed if you stall against the foot brake too, or simply if your engine makes a lot of power.

The higher the stall speed, the more it's going to slip on the highway. This makes heat, and you will need a big transmission cooler. It will also reduce your fuel mileage.

Personally, with no real guidance on stall speed, and if you don't have a buddy running one that can give you some real world feedback on that, I'd pass on that one and keep shopping.

55 Tony
08-21-2018, 06:02 PM
They sort of hide the stall rating. It's rated at 3,000rpm. The cam calls for 2500+. My current one is rated at 2400rpm. IDK, is an increase of 600 worthwhile?

https://www.summitracing.com/parts/sum-g2698/applications/advertised-flash-stall-rating-rpm/3-000-rpm/transmission-type/th400

Rick_L
08-21-2018, 07:03 PM
It will certainly make a difference in both performance and cruising. I can't say how much.

markm
08-22-2018, 06:18 AM
I have never been a fan of discount convertors, go with a name brand A1, TCI etc stay away from Alabama Boss Hog, GER Here is a clue in the early 80s I paid $250 for a 10 inch TCI street strip convertor, that was rebuilt in the 90s to 10 inch race and it still resides in my 74 Z28 drag car. Yes, it has an anti balloon plate. If you want cheap go find an old Vega and pull the convertor.

55 Tony
08-22-2018, 05:50 PM
I've had an engine vibration for a long time now, don't remember when it started, so while the tranny is out was thinking of changing the flex plate. With the side mounts in place and the exhaust holding most of the weight plus a jack also underneath the motor, I started it up and I get no vibration. Smooth as silk. I had tried it before with the converter unbolted and slid back and then it still had the vibration. So why not now? The only thing I can think of it that the center of the converter may have still been inside the crankshaft a little bit.

Rick_L
08-22-2018, 06:55 PM
No good reason, what you suspect may have been the cause but it shouldn't have if it wasn't rotating. Was it rotating or not?

BTW, I fully agree with markm's statements about cheap torque converters. You get what you pay for in most cases.

55 Tony
08-23-2018, 05:18 AM
No, it wasn't rotating with the 3 bolts out, I don't *think* it was anyway? That was the purpose of taking the bolts out. That converter is a TCI. I know this wouldn't be normal practice, but do you think I can bolt the converter on without the tranny and start it without a catastrophe? My *new* tranny came with what I assume is a factory converter, so if it vibrates with my TCI I could double check with the factory one.

55 Tony
08-23-2018, 05:33 AM
This may be stupid but it won't be my first time, can you tell if this looks like a stock GM converter?

Rick_L
08-23-2018, 05:55 AM
Sure looks stock to me. Is it 12" diameter? Looks to be.

markm
08-23-2018, 06:01 AM
Yes, but no, that looks like the OEM Convertor from my first 74 Z28 that was destroyed in August of 80. They used 6 mounting points with 3/8 bolts and were rated at 2400 stall. A Z28 was the only Camaro equipped with a TH400 in 74 as they were considered special high perf. I have also seen the 6 lug convertor in 1 ton trucks, no idea on their specs.

TrifiveRichard
08-23-2018, 06:07 AM
My two cents Tony, if the car is driven mostly on the street, the 3000 rpm stall is too high for me. The converter is too loose and the rpm has to change so much just to make small changes in speed, so the motor seemed to go from idle to 2500 or so continuously.

Another comment on the vibration, I had a problem and it turned out to be the engine damper, even though it was a new TCI with no visible signs of a failure. I changed it out and the vibration went away.

55 Tony
08-23-2018, 06:29 AM
Yes I didn't think of measuring it. It's almost 13", my current one is about 11.5". That would have been slick if it was 10" I would have given it a try.

55 Tony
08-23-2018, 06:53 AM
Thanks for the input Richard. I had changed the harmonic balancer a while ago with no change. My current TCI is rated at 2400

TrifiveRichard
08-23-2018, 12:49 PM
That’s the same value we swapped in. The motor was a carb’ed 383, hydraulic roller, aluminum heads with a 200R4 trans (w/lockup converter on a toggle switch) and 3.23 gears. It worked well.

55 Tony
08-23-2018, 02:18 PM
Hmm, so maybe if this converter isn't causing the vibration, I should leave well enough alone? And your locking converter, I have often thought of using a simple toggle switch just for on the highway. Was it a full manual valve body too? If I did that I'd add just a little bit of electronics with a relay that unlocked it at low speeds and/or really simple a relay activated by the brake lights that cut off the lock up.

chasracer
08-23-2018, 05:02 PM
I have to go with the general consensus here. When it comes to converters it's best to deal directly with a manufacturer, give them all the information you can about your engine, your chassis setup and how you are using the vehicle. Most of them can steer you in the right direction which in your case is probably going to be a 10" street unit that with your BBC should be able to hit 3400-3600. I am not sure I follow the vibration information but connecting the converter might be okay but now sure it proves anything. I would install a new flexplate at the same time, preferably an SFI one, you will need new bolts for the converter and make sure you measure everything properly to get the new converter installed correctly. If you have any questions on that I have a little write-up on my website that may help you out, just let me know.

55 Tony
08-23-2018, 06:02 PM
3400 to 3600 sounds pretty high when the cam only calls for 2500+ (doesn't say plus how much)? As far as the vibration, since it doesn't vibrate now, and I add the converter - then it vibrates, that would tell me my converter is off balance. But damn, unless I raise the car high enough that I can sit up under it, I don't think I can hold the converter itself up while I struggle to get a bolt in, then turn it. I have an SFI flex plate coming, and a flex plate engine turning tool also. It would have been here today but ups says they mis-sorted my package.
Sure, shoot me a link to your web page and I'll give it a read.

chasracer
08-23-2018, 06:32 PM
Well, there's a difference between "stall or flash rpm" and operational rpm for a converter. I mean we drive around the pits with 8" units that will flash anywhere between 5800 and 6200 and it's no different than leaving a stop light and going down the street. But, if we hammer it that's when you see the difference. So while a flash of 3400-3600 might seem a bit high under normal usage a street style 10" unit is pretty livable. Yes, there's a bit more heat involved but you would be running a trans cooler anyway so that's not even an issue. Typically what we see in ads as far as stall RPM, the number is usually based on a reasonable small block motor combination - a BBC deal simply has more torque at the outset so the numbers are going to be a bit higher. Case in point, we have a Hughes unit in the Corvette roadster that we are trying out. Hughes told us that converter should flash somewhere in the 5100-5200 area but the 421 inch small block we have in the car is pretty healthy with just shy of 700 hp on tap so this converter is actually flashing at 5800 right now. If I put it behind my 555 BBC engine, it would probably go a touch higher. I am sending you the website link in a PM.

Rick_L
08-23-2018, 06:37 PM
chasracer is not agreeing with the "consensus" I'm reading because there isn't one.

He is advocating a 3400-3600 stall.

Trifiverichard is advocating 2400 stall.

My advice was that increasing the stall from 2400 to 3000 increases the heat and slippage, and decreases the fuel mileage while increasing the performance (but only if you don't spin the tires, because you're going to be closer to doing that).

So it's up to you to decide and find out what the real tradeoffs are between a driver and a race car. There is no pat answer.

TrifiveRichard
08-23-2018, 08:07 PM
And your locking converter, I have often thought of using a simple toggle switch just for on the highway. Was it a full manual valve body too? If I did that I'd add just a little bit of electronics with a relay that unlocked it at low speeds and/or really simple a relay activated by the brake lights that cut off the lock up.

youre right, the lockup was engaged with a simple toggle switch and was used just for hiway cruising. A latching relay could be used and reset with the brake light switch.

markm
08-24-2018, 06:30 AM
chasracer is not agreeing with the "consensus" I'm reading because there isn't one.

He is advocating a 3400-3600 stall.

Trifiverichard is advocating 2400 stall.

My advice was that increasing the stall from 2400 to 3000 increases the heat and slippage, and decreases the fuel mileage while increasing the performance (but only if you don't spin the tires, because you're going to be closer to doing that).

So it's up to you to decide and find out what the real tradeoffs are between a driver and a race car. There is no pat answer.

Very well put, you cannot have your cake and eat it too. This is why I have two purpose built race cars and a dozen street cars and trucks.

Rick_L
08-24-2018, 06:38 AM
The relay circuit needs some sort of speed sensor or pressure sensor to keep it from applying in the lower gears. The easy way is to wire it up similar to stock but add a toggle switch if you think you must have one. Keyed power > toggle switch > brake switch > vacuum switch if used > connector on side of trans > 2 wire lockup solenoid > pressure switch > ground. That's for a 1 wire pressure switch with a grounded body that screws into the valve body. There are other variations with 2 wire pressure switches and 1 wire lockup solenoids. No relay required with this method.

How did a lockup converter get in this thread about a TH400 torque converter? TH400 doesn't support lockup torque converters.

55 Tony
08-24-2018, 08:52 AM
e was that increasing the stall from 2400 to 3000 increases the heat and slippage, and decreases the fuel mileage while increasing the performance (but only if you don't spin the tires, because you're going to be closer to doing that).



I was going to mention that the last few times since I wasn't doing long smokey burnouts I wasn't hooking like I did at first. I had intended to try a slightly longer burnout and a little less air. Although I guess I should only change one thing at a time.

Wish I could go to the track right now, it's 60° with very low humidity. We are getting some beautiful weather here. Well I forgot to send this, it's up to 70°

chasracer
08-24-2018, 12:24 PM
chasracer is not agreeing with the "consensus" I'm reading because there isn't one.

He is advocating a 3400-3600 stall.

Trifiverichard is advocating 2400 stall.

My advice was that increasing the stall from 2400 to 3000 increases the heat and slippage, and decreases the fuel mileage while increasing the performance (but only if you don't spin the tires, because you're going to be closer to doing that).

So it's up to you to decide and find out what the real tradeoffs are between a driver and a race car. There is no pat answer.

I'm not advocating any particular stall rpm or converter size. I simply said that based on how he uses the car reported on this site, that's probably close to what a manufacturer would wind up recommending to him. There are always trade-offs but I do not believe this car is the get-in and go to work vehicle save for an emergency so except for a little extra heat and who cares about gas mileage, the car would drive just fine. My general consensus statement was aimed at contacting a converter manufacturer directly which was already mentioned a couple of times. Lastly - what I normally find is that "most" hot rodders may have purchased one re-worked converter in their tinkering, usually replacing a stocker or during the build-up of a new ride. They probably don't have 8-10 of them stacked like cord wood in their shop - but that's how you find out if the latest hot lick works for your combination or not. Anyone interested in a 7", 8800 converter? Got two of them almost new - first $2000 takes one - free shipping. You better be able to wind that small block to at least 10,500 to make use of it!

55 Tony
08-27-2018, 02:44 PM
I was looking at this:
https://www.summitracing.com/parts/ape-46013/overview/

This is what Boss Hog recommends for street/strip:
https://www.summitracing.com/parts/ape-47713
Supposed to be 2800 ~ 3200 stall.

Then I asked what if I was looking at more strip than street and they recommended this:
https://www.summitracing.com/parts/ape-47733/overview/
Supposed to be between 3200 ~ 3500 stall.

Asked what the difference was between my choice and theirs besides $300 and they said strength. With all my specs they said the cheaper one is really borderline.
They did also have concerns about my trans cooler line first go through the radiator, they say to bypass that. I was under the impression that a tranny can run hotter than the coolant and the radiator cooled it some and the trans cooler cooled it more? At first they thought I needed a bigger cooler but then with the cast aluminum pan that holds a few extra quarts I should be OK.

Also questioned my 3,950 lb weight estimate and I told them I figured it like this:
3370 Curb
60 gas
150 BB
40 12 bolt
100 th400
40 caltracs
230 me.
= 3950 lbs.

Comments? (besides me going on a diet)

55 Rescue Dog
08-27-2018, 03:56 PM
It's always helpful to know what the weight of your vehicle, or trailer is. There are plenty of places that have certified scales you could weigh it at for a few bucks, or less, which I have done many times. Wheel scales are on my list, hoping to stumble on a steal on a set. It would be great to know the load on all 4 tires.

markm
08-27-2018, 04:06 PM
A good quality convertor 3200-3500 is fine, I would stick with A1, TCI, or Coan. Not a fan of cheap stuff.

55 Tony
08-27-2018, 05:40 PM
Yes, I had hoped to weigh it sometime but now it's tough since it isn't exactly mobile.

Rick_L
08-27-2018, 06:53 PM
Weight isn't really an issue as long as the body/interior is essentially stock. It's going to weigh 3700 or so with a big block.

Your comment about the radiator cooler doesn't apply with anything 2400 rpm stall and up. With that you need a big cooler and don't run it through the radiator cooler.

You simply need to decide two things. What stall you want knowing that bigger is a detriment to highway driving. And whether you want to use a name brand or cheap out. We can't decide that for you, it's up to you.

55 Tony
08-28-2018, 04:25 AM
So 3700 plus me is 3930, close enough.

Your comment about the cooler doesn't make sense. The hotter the transmission, the more the radiator cooler will do to cool it since the coolant temp will stay about constant.

I've heard of this brand for many years, not sure what the name brand/cheap comments mean. The one they recommend is not exactly inexpensive at $630.

markm
08-28-2018, 05:56 AM
Weight isn't really an issue as long as the body/interior is essentially stock. It's going to weigh 3700 or so with a big block.

Your comment about the radiator cooler doesn't apply with anything 2400 rpm stall and up. With that you need a big cooler and don't run it through the radiator cooler.

You simply need to decide two things. What stall you want knowing that bigger is a detriment to highway driving. And whether you want to use a name brand or cheap out. We can't decide that for you, it's up to you.

Good advice here, time to put up or shut up. FYI I use radiator cooler with aux cooler on trucks only not on HP applications.

chasracer
08-28-2018, 02:18 PM
I'm not a big fan of using the radiator cooler unless we are dealing with a tow truck or something similar that doesn't stress the transmission temperature all of the time, then it makes sense to me to loop it through the radiator unit. For performance, stay with as large a stacked cooler as you can handle and my preference is AN type fittings/hose for the connections. Metal line would be fine too but stay away from rubber hose and hose clamps - eventually it will bite you.
I understand that $630 might seem pricey especially when you are not positive of what you might end up with but going with a well known converter company may cost another $100 but it's normally worth it just in getting support and decent workmanship. I can recommend TSI, TCI and BTE as companies that I have never, ever had an issue with but I cannot recommend FTI, Hughes or any of the smaller companies. I hate to say that because some of them are just fine I am sure but you're spending some decent money and you do not want any issues. There are other outfits out there with good reputations too, JW, A-1, Coan and Rossler come to mind but while I have used parts from JW, I have never had a converter from any of them.
And I find it kind of funny that what I said about the stall speed number was almost dead-on.

markm
08-29-2018, 06:26 AM
I just go my 8 inch bolt together back from local rebuilder $150. It started our life as an A1 over 20 years ago and was rebuilt to current state by local rebuilder something new its caliber is probably in the $1200 range. THe good news is quality stuff is worth fixing. Had a GER once in a BBC Chevelle it wasted my front pump on startup..

55 Tony
08-29-2018, 09:43 AM
Curious if your 8" had a failure or it was getting preventive maintenance like bearings or something?

Do you know what exactly went wrong with the GER one? Again, I'm just curious.

Also do you fill them half way before installing?

chasracer
08-29-2018, 10:27 AM
Oh yea, the GER crap was a real winner. They sold me something that was supposed to be a decent converter for my '66 Chevelle bracket car. The damned thing was never right and I sent it to TCI to have them go through it - they called me back after cutting it open and said it was worthless. Someone had used a pair of pliers on the fins to change their angle. TCI guy said the fins were all over the place!

You can normally get a full quart of trans fluid in the converter - that's all you need to get it going.

Markm - leaning towards a Rossler bolt together the next time around. At least that way with some spare hardware you can change up what the converter is doing for you.

markm
08-29-2018, 10:54 AM
Curious if your 8" had a failure or it was getting preventive maintenance like bearings or something?

Do you know what exactly went wrong with the GER one? Again, I'm just curious.

Also do you fill them half way before installing?

About 15 years of use and countless passes a PM thing but it was a good idea. Inspection showed a some worn parts in need of service.

The GER converter had little pieces slag on hub which was rough as a cob and unfinished.

Bolt togethers are expensive but I think they are worth it. I would still like to kick George R Reynolds in the ass.

55 Tony
08-31-2018, 05:06 AM
After talking to TCI, I ordered one of theirs. It's rated at Summit for 3000 stall but the guy at TCI said with my motor it should be closer to 3200 - 3400. Should be here today or tomorrow.

markm
08-31-2018, 06:07 AM
My mid 7 second in the 1/8 355 SBC 74 Z28 has a 35 year old 10 inch TCI. It was converted from street/strip to race by them in the 90s, good stuff. I think you will be happy.

55 Tony
08-31-2018, 07:53 AM
About $160 cheaper than the other one also. I also opted for the anti ballooning plate. I know I don't need it now but who knows down the road. Damn, according to updated shipment tracking it won't be here until tomorrow. At least FedEx delivers on Saturdays, otherwise it wouldn't be here until Tuesday.
I wonder if the damn track will be open on Labor Day? So far only Fri and Sat, no Sunday's. The old owners used to open Sunday if Sat was rained out.

55 Tony
08-31-2018, 11:23 AM
This may be stupid but it won't be my first time, can you tell if this looks like a stock GM converter?

I keep forgetting to ask if it is worth anything or is it scrap metal? I'm assuming it's scrap. Pics on post #9.

markm
08-31-2018, 01:15 PM
That is either a hp model or hd with six lugs, I would think it has a core value.

chasracer
08-31-2018, 04:52 PM
Take the time to replace the front seal on the pump, lube the inner part of the seal with a touch of white grease and 1 quart of fluid in the converter. If it's been a while on trans service, you might want to dump the fluid and replace that too. Good luck with it, TCI was some of the first "good" automatic trans stuff I ever used and it never let me down.

55 Tony
09-01-2018, 05:35 AM
Replaced the front seal already. My old converter is a TCI "Break Away" series. Never had a problem. Still have the invoice, $179.69. I'm keeping the Break Away in case I quit racing. I'll probably decide that when it's time for new slicks, or if I break something.

The extra converter in the pics came with the donor tranny, guessing it's stock from the Suburban it came out of. Funny, the *new* trans is out of the same make and model as the old one. Broken case has a cast "12" up top, good case has a "13", my lucky number.

55 Tony
09-02-2018, 10:21 AM
Finally late yesterday FedEx showed up with the converter. Finished up today checking everything three times and took it for a ride. It has a *whirring/whine* sound that can be heard when in or out of gear, I'm hoping that's normal, or common? Drove it and yes it does seem to slip a lot until it kicks in. The whine isn't noticeable as soon as I start moving. Going about 40mph in third I don't hear a thing but if I stay off the throttle and down to 2nd gear I hear the whine. Don't tell me the pump took a crap. Fluid level is good and I put 2 O rings on the pickup tube. It ran fine and there was no foam or bubbles on the dipstick.

I know it isn't the proper way of checking stall speed, but in the driveway with the parking brake on and the brakes almost to the floor it gets up to 3400rpm before the street tires spin. So how that may translate to real stall speed I don't know?

So the whine and the stall speed, what do you think?

Update: The whine went away! I'm guessing there was some air stuck in there somewhere but now it's quiet.

chasracer
09-02-2018, 03:55 PM
Might not be the exact way to check one but it appears to be about dead-on to what they said it would do. Now it's back to testing and tuning to get the most out of it. Have fun!

55 Tony
09-03-2018, 05:12 PM
Crap, the whine is back, just at certain speeds and rpm's. Sounds like I have a blower.

chasracer
09-04-2018, 01:36 PM
Usually low pump pressure although a few other areas can cause the same type of noise. Try looping your cooling circuit at the trans and see if the whine goes away.

Rick_L
09-04-2018, 03:41 PM
On the whine, are you sure that the oil level is high enough? Are you sure that the pickup tube seals at both ends and the filter is on the tube?

chasracer
09-04-2018, 03:49 PM
Actually the filter on the end of the tube isn't important, in fact I used to run my TH400's without filters, just used a piece of aluminum screening to keep out large debris. Now if the o-rings and tube are dislodged, that could be an issue. But, he already said he checked all of that - really sounds like a pressure issue going on so my other question is I am assuming that the guts of the previous trans were transferred to the new case and the new converter was dropped in place. So, it might be a good idea to loop the cooling ports, see if the resultant increase in pressure stops the whining and if so, then see about borrowing a pressure gauge to verify the actual pressures that are being generated. There is a possibility that the new (replacement case) has a hairline crack in it resulting in an internal leak.

Rick_L
09-04-2018, 04:54 PM
Blocking the cooler line ports does not decrease line pressure at all. I don't recommend doing it because you do need a cooler. And a cooler is a must with 3200 or so stall speed, if driven on the street. Running a cooler is essentially a loop unless the lines are too small - it's just a longer loop. There is a bypass valve in the pump that internally connects the "cooler out" and "cooler in" fittings. It opens at less than 10 psi. But that's cooling circuit pressure not line pressure. Cooling circuit pressure is usually very low unless you stall the converter against the brakes (or a transbrake). The pressure goes very high when the converter is stalled and the output shaft is stationary or very slow. But it still doesn't go to line pressure, and line pressure never changes unless the pump is oil starved.

You did make one correct point. The seal at the lower end of the pickup tube doesn't need to be a good one, except that you lose any filtering. One thing that could go wrong though is that if the filter (or whatever you use) isn't correctly attached to the pickup tube, it could block the pickup tube, and that would be a problem - as you said.

55 Tony
09-05-2018, 07:02 AM
I don't know why I didn't do this right away, but I put a gauge on it.
Park 70
Reverse 115
N 70
D 75
2 150
1 150
And this is with a high pressure shift kit spring.
Also in 2 and 3 it fluctuates 30 or so psi with 150 being the average.
I suppose I have to drop the pan and double check the O-rings on the pickup tube. I hadn't done that, I just put 2 on when I put the tube in. Luckily I have a drain plug. Oh, and I thought it was shifting pretty soft, these pressure readings tells me why. Cross my fingers that's all it is. I guess I didn't put a gauge on it right away because I thought/read that the oil will have little bubbles/foam that show on the dipstick. This is my old pump and I didn't open it up, just swapped it to this case.

Rick_L
09-05-2018, 08:19 AM
Also in 2 and 3 it fluctuates 30 or so psi with 150 being the average.

There's your real problem. I think it's starving for oil as already discussed.

55 Tony
09-05-2018, 09:16 AM
I just dropped the pan to check the O rings on the pickup and they were fine, even added a third. Same exact readings. Fluid is full with a deep extra capacity pan. Putting the fluid back in I thought I noticed microscopic (or almost) sparkles. It was new fluid with the case change. The drain plug magnet also had what I'd say was a lot of fine metal for the 20 miles I put on it.

The fluctuation is actually in 1st and 2nd, not drive. the gauge goes up and down probably 2 or 3 sweeps/second.

chasracer
09-06-2018, 02:25 PM
I don't know why I didn't do this right away, but I put a gauge on it.
Park 70
Reverse 115
N 70
D 75
2 150
1 150
And this is with a high pressure shift kit spring.
Also in 2 and 3 it fluctuates 30 or so psi with 150 being the average.
I suppose I have to drop the pan and double check the O-rings on the pickup tube. I hadn't done that, I just put 2 on when I put the tube in. Luckily I have a drain plug. Oh, and I thought it was shifting pretty soft, these pressure readings tells me why. Cross my fingers that's all it is. I guess I didn't put a gauge on it right away because I thought/read that the oil will have little bubbles/foam that show on the dipstick. This is my old pump and I didn't open it up, just swapped it to this case.

All of your readings are at minimal values or just slightly above on the 3rd (D) one. So I think maybe you can rule out a crack in the case somewhere but I would check the valve body/case for flatness and make sure you're not leaking there. And I said loop the cooler lines at the trans, not block them and only do it as a quick test to see the noise changed or went away.

markm
09-07-2018, 07:56 AM
Tony how many quarts did it take to fill your TH400, I just had my convertor serviced and did a filter change and put 10 quarts of Type F in and ended up draining 2 out and adding a pint. I figured the 8 inch convertor was offset by deep pan.

55 Tony
09-08-2018, 01:55 PM
Tell me, if before the tranny case swap there was no metal larger than fuzz, now there is metal of considerable size in the pan and the pump pressure is low (for the high pressure spring in the shift kit), what could I have done wrong? Or would you suspect the converter? Does all fluid coming out of the converter have to travel through the filter before getting to the pump? I just pulled the pump and opened it up, the gears have what looks like scrapes in the worn part, but fine enough that I can't feel them. Shaking the converter upside down yielded no metal. What did I F U ?

Rick_L
09-08-2018, 04:23 PM
All the oil, no matter where it goes originally, dumps back into the pan. The oil that goes inoto the converter comes back out of it and into the cooler lines. The return cooler line feed lubrication oil to the front part of the rotating assembly and then drains into the pan. The only filtering is on the suction side of the pump.

Is the stuff in the oil steel (pick it out with a magnet)? Metallic but not steel? Not metal? You need to find that out before any internet diagnosis. But even at that, an internet diagnosis is just a WAG.

55 Tony
09-08-2018, 05:54 PM
It sticks to a magnet. What is in the picture is from about 10 miles driving. No noise except the whine and it does that when or when not moving.

Rick_L
09-08-2018, 07:54 PM
Looks like a tear down is in order.

chasracer
09-09-2018, 05:37 AM
Yep - do it now, its not going to get better on it's own. When you swapped your hard parts to the new case you did check all of the clearances? I mean it's basically a rebuild at that point with a soft kit. Reputable converter builders flush out the units with a flushing machine (even my local trans builder has a converter flusher) and normally bolt up the units to a mule engine for test. Leaks are usually done with an air adapter and water. Before reinstalling the converter either get it flushed locally or do it at home. I have poured mineral spirits in, sloshed it around good and then let it sit upside down on a plastic bucket to drain - sometimes over night. I repeat until I am satisfied that nothing else is coming out. Normally you might see a little bit of what is in the pan the first time, any more than that raises a flag for me. Last - how much clearance was there between the converter mounting lugs and flexplate during installation?

55 Tony
09-09-2018, 09:12 AM
Clearance at the flex plate was 3/16", I had considered shimming with washers since that was the recommended max (I thiink), but didn't.

The only local transmission shop doesn't have a flusher. He sells everyone a new converter if they want a warranty.

I just tore it down and can't find a speck of metal anywhere besides what you saw in the pan. Don't see any damage to any bushings, thrust washers, gears, anything. Certainly the amount of metal in the pan would have showed up somewhere. Would you say (or guess) that it had to come from the converter?

Are you saying the amount of metal I found is almost common or it's a big red flag?

chasracer
09-09-2018, 12:10 PM
The 3/16" clearance on the lugs to flexplate is good and would not be part of the problem then.

Looking at the picture again of the oil pan, the amount of metal is not "killer" but when we combine it with the noise issue then you have to wonder if something is tearing itself up. I would take a good hard look at the planetary and make sure that all of the gears are perfect, that the clearances are good and there is nothing else that might be failing - such as the sprag. After that I would concentrate on the pump. The minimal pressures that you recorded along with the fact that you put a heavier aftermarket relief spring in the pump just doesn't add up. Again, I would check the pump gears for issues, their clearance and make sure nothing else is out of whack. Make sure the stator is where it is supposed to be in reference to oil hole alignment. I would also still verify that the surfaces of the valve body and it's mounting surface are dead flat and free of any burrs. Correct valve body gaskets? Check balls in the right spots? I would flush the converter a couple of times, use a paint strainer but I think you will be okay there.

Just for info - I shattered the rear thrust bearing on the TH400 in my Chevelle one time, it didn't take any time at all to turn the fluid into aluminum paint as the gear train moved back and started shaving the rear of the case. I had my machinist cut the rear output for a Torrington bearing which fixed the issue and I never built another TH400 without doing that same procedure. But even with all of that aluminum floating through the entire trans and converter, it didn't hurt anything. Biggest deal was just cleaning it all up with a lot of brake cleaner. The metal you have came from somewhere but stayed in the bottom of the pan - just need to try and find where it came from.

55 Tony
09-09-2018, 05:20 PM
Note the thrust washer stuck on the front. Should it be there? It wasn't. Without it, it looks like the various oil passages could have been off their mark. Enough for lower oil pressure? By the way, out of two transmissions, I only have one washer that size. I'm pretty sure it was missing in the donor trans.

chasracer
09-09-2018, 05:27 PM
Yep - it's supposed to be there - bet you just figured out the low pressure/whining sound!

55 Tony
09-09-2018, 05:48 PM
I've done it before but I'm no expert at this as you can tell. This last time I took pictures as I took the donor trans apart. Dumb move, I should have done it to the one I knew was working before the case cracked.

FedEx is supposed to pickup the converter tomorrow, should I rinse it out and cancel the return? I know there is no definite correct answer, just asking for opinions.

Rick_L
09-09-2018, 06:56 PM
There's no way for us to know. It's probably OK with a flush. But we have no way of knowing.

You need to check and adjust all the thrust clearances. They can definitely change with a case swap. I'll bet you can find all the thrust info on the internet. But you certainly can find it in the Ron Sessions book on TH400 transmissions. A missing thrust washer could definitely cause your symptoms. You might be lucky to have caught it before everything was trash.

Did you put new clutches/steels and sealing rings in it? Especially sealing rings. And you need to air check the sealing rings (procedure in the book).

55 Tony
09-10-2018, 05:14 AM
Yes I have the Ron Sessions book and go by that. I had completely rebuilt it just a couple years ago and really don't see the need for a complete rebuild.

Rick_L
09-10-2018, 05:30 AM
It's possible to break a sealing ring during assembly, or if using plastic ones, just have one get out of place. You won't know until you have a look.

55 Tony
09-10-2018, 06:01 AM
Oh, those rings. I'm using the steel/cast ones. I thought you meant the rubber rings for the piston/clutch pack things. I have no luck getting them in and last time had the local shop do one of them for me. The cast rings all look OK. It really worked GREAT until the case broke.

55 Tony
09-10-2018, 06:05 AM
It didn't make sense until now, but the donor trans had 2 snap rings holding the one section in, I guess to take up the room for the missing thrust washer, so that's what I did. Yes I know, not real smart but I am learning.

chasracer
09-10-2018, 01:04 PM
Honestly for going through all this trouble, a soft kit would be the least I would do and now since I know you have Ron's book - it's a bible on Th400's - then you don't have any excuses.:) I usually put some trans fluid on the sealing rings and use a .010 feeler gauge. Just some light pressure and the sealing rings go right in. I also prefer the teflon seals to the cast iron ones but it's not a show stopper. Trans Fluid in a Windex bottle and petroleum jelly are your best friends during a rebuild. And yep, clearances can certainly be different on different cases but at least they are easy to correct in a TH400 unit.

55 Tony
10-15-2018, 03:15 PM
After talking to TCI, I ordered one of theirs. It's rated at Summit for 3000 stall but the guy at TCI said with my motor it should be closer to 3200 - 3400. Should be here today or tomorrow.

After working on the different carb and going for a short test run, my driveway is pretty steep uphill. I stopped at a steep part, yanked the parking brake all the way and pumped and held the brakes to the floor and nailed it and the tires didn't spin. The rpms went up to 4000 and stayed there. It may have flashed a little higher but my tach is slow to react so I don't know. So Summit said it's 3000 stall, tci with my engine info says 3200 to 3400, and it goes up to 4000 in the driveway? Is this thing a bit looser than it's supposed to be or is that just how it is? I know to me, never having had a high stall converter before, it sure has to rev to get out of it's own way at a stop sign or light turned green. Between 1600 to 1900rpm to move. That isn't slow but it's far from a a jack rabbit start. So is it just the nature of the beast or is this thing crap?

55 Tony
10-17-2018, 07:41 AM
After working on the different carb and going for a short test run, my driveway is pretty steep uphill. I stopped at a steep part, yanked the parking brake all the way and pumped and held the brakes to the floor and nailed it and the tires didn't spin. The rpms went up to 4000 and stayed there. It may have flashed a little higher but my tach is slow to react so I don't know. So Summit said it's 3000 stall, tci with my engine info says 3200 to 3400, and it goes up to 4000 in the driveway? Is this thing a bit looser than it's supposed to be or is that just how it is? I know to me, never having had a high stall converter before, it sure has to rev to get out of it's own way at a stop sign or light turned green. Between 1600 to 1900rpm to move. That isn't slow but it's far from a a jack rabbit start. So is it just the nature of the beast or is this thing crap?

Bump

chasracer
10-18-2018, 06:02 PM
I actually wrote you a response yesterday but then erased it. After the BS from our friend again, I was about ready to abandon this forum too. Getting damned tired of these "know it all's" that usually can't do anything but repeat something they heard like a damned parrot.

Anyway, on to your issue. The bottom line to me is that you have hit the point where the car is in the twilight zone now. It's a bit more race car than it is street car at this point and slippage in the converter is just something that you have to put up with until you develop more horsepower and torque from the engine. You can of course always send the converter back and tell them to tighten it up if your leanings are to have it behave a bit better on the street. If it were mine I probably wouldn't do that but I lean heavily towards performance and the hell with everything else. I don't know if you have had the chance to test the car at the strip yet, if so I must have missed the post. You also have to remember that every time you make a change you have to go through the re-tuning process. What worked with the other converter might be close with this one or totally out the window. Also, your method for checking stall is not the normal one that most of us use. In fact most transmission places will tell you same thing, roll along at 15-20 mph on a flat area, have it in high gear and whack it hard - watch the tach and see what the number is. You also have said repeatedly that the tach is slow - I would suggest replacing it with something that you can count on and know is accurate.

55 Tony
10-19-2018, 03:57 AM
I've been doing really good about not *peeking* and reading his posts. Only a couple times and they weren't his asshole ones. IMO missing his posts that are good are not enough to make up for the ignorant childish ones.

The problem with testing that way is that it's not a full manual valve body, so it would hit 1st. I did realize that at light throttle it was shifting pretty early so I turned the modulator valve screw in a couple turns so maybe if it doesn't shift so soon. Yes that will raise the rpm's, but my hopes are for less slippage at light throttle. I have some time today, I'll try to install the new tach that has been sitting here for months. For some reason certain things keep getting pushed aside.

chasracer
10-19-2018, 05:30 AM
Sounds good. Maybe you could ease it up to high gear, then whack it a good one?

And yeah you're correct, my mistake on looking at his posts - it was okay until he got all pissy about not accepting his viewpoint as the only acceptable one.

Good news is that I am a couple days from finally finishing a house flip (5+ months now) so I am getting ready to drag my '55 back in the shop for some major work this winter. I am aiming for the first TnT sessions at the strip in the spring. We normally get going around here about mid-March depending on the weather of course.

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55 Tony
10-19-2018, 07:24 AM
Sounds good. Maybe you could ease it up to high gear, then whack it a good one?

My governor is set to shift at 5500rpm at WOT (since it isn't a full manual valve body) so I'd have to be somewhere over 60mph for it to not kick down and stay in 3rd. On second thought, I could probably go much slower and nail it if I disconnect the kickdown switch at the carb.