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Eds56
09-20-2016, 05:19 AM
Hello All,

My Son has been after me for awhile now for us to do a "father/son" engine build from my stock pile of parts, So I would like some feedback on what i have in mind....and or possible suggestions. The engine will likely go in my 56 at some point and as currently, will remain a weekend driver (No Drag Strip).... like a lot of others, i want all the POWER to the wheels i can get from red light to red light and still burn pump gas. As much as i really like the current 327.....I've always been told that MORE Cubic inches is the way to go.

Looking for low RPM power....not pushing RPM's thru roof.

400 small block (4 bolt main) bored 30 over ---- Also have same block standard bore too.
Crank suggestions--?? thinking of having it stroked to 3.875 --- or should leave it?
5.7" or 6.0" rods?
Piston type?? (Hyp....Forg....flat....dome)
Aluminum Heads -- Any specific recommendations, esp flow rate?? --Also-- I have a good set of #186 heads i could use, but was saving those to replace the old 461 double humps on the 327.
Cam type & size
Intake -- Have a Edlebrock Torker single plane.....but may replace it.
Engine will run a 4-speed tranny & Current Rear End Ratio is 3:08 ...... but i also have 3:36 ---- 3.55-----3:73

Yes, I know 400's have possible block issues and I understand to go with longer rods / crank combo will require machine work. And I have already looked at just buying a crate engine, or Rotating assembly, or even a short block and go from there.....BUT, that's not the direction i want to go at this time.


Thanks,
Ed

markm
09-20-2016, 06:00 AM
A local friend of mine who built a number of good running 400 SBCs actually prefers to start out with a late 400 two bolt block. The ones he likes have 509 cast in the side. The story goes they have thicker decks and more metal in main area. One of these with splayed mains is your ultimate stock based block. The early 4 bolts are your weakest design. 6.0 rods are the way to go. You have not given near enough info to recommend any camshaft.

Rick_L
09-20-2016, 06:32 AM
To my knowledge markm is correct on the block - the 2 bolt with aftermarket caps is the preferred deal.

As long as you use a 64cc head, there's no need for anything other than a flat top piston for a street engine - you will have plenty of compression.

I would stay away from the short stock rods (5.55"), and there's no good reason to do anything other than a 5.7" or 6.0". No special machine work or parts required if you get pistons that match the rod length.

A 186 or other double hump head is pretty small for a 400, it's going to respond a bunch to a bigger aluminum head.

Given your description, there is not much reason to go for a big cam.

markm
09-20-2016, 06:41 AM
I am not sure you eve want a FT piston with a 64 CC head as that's pushing 11-1. I would look in to aftermarket Alum with 72-76 CC for pump gas.

chevynut
09-20-2016, 08:31 AM
Wow, the guy clearly says he wants to build a "weekend driver" engine with his "stock pile of parts", and that he knows "400's have possible block issues" and the first response is to suggest he use a different block. :D I'm sure his block is just fine for what he has in mind for the engine and all the bs about different blocks is irrelevant to his stated objectives.

If it was me I'd go for as many cubic inches as you can get since what you really want to get from red light to red light is maximum low and mid-range torque. You're not going to rev the engine to 7000 RPM in that situation. If you need to get a crank anyhow, why not get a stroker? I'm not familiar with all the SBC heads out there but I'd consider your budget and get the best ones you can afford since heads are largely what determine airflow and more airflow makes more power.

It's my understanding after going through the exercise myself that you really need to decide on every other aspect of your engine before you choose a cam, especially the heads. Don't get into the mode of believing that more duration is always better like some guys claim. More duration shifts the torque curve upward, which is not what you're looking for.

JT56
09-20-2016, 09:24 AM
There is a huge difference from a 327 or 350 to a 400 sbc. This can be a slippery slope to go down...more power is addictive. Do you plan on keeping those gears?

JT56
09-20-2016, 09:29 AM
There is a huge difference from a 327 or 350 to a 400 sbc. This can be a slippery slope to go down...more power is addictive. Do you plan on keeping those gears? The 3.73 is the best for light to light in what you currently have. However with a manual transmission and the stock rearend...spinning is your friend! Dumping the clutch to many times and it wont hold up! I know you have said weekend driver. What are you plans? Cruise 50 miles from home or just go to the local hangouts?

markm
09-20-2016, 10:37 AM
A mild 400 with 9.5-1 CR, with some mid range alum heads, Performer RPM intake, and a .480 lift cam, decent street tires add some aggressive stoplight to stoplight driving will send a stock rear end to scrap pile.

Eds56
09-21-2016, 04:53 AM
Thank You to everyone for the suggestions, you have given me plenty to mull over. At the moment, i'm just looking to put some ideas to paper, then i'll have my block & crank checked out to verify they are as good as the "guy" said. Still looking at several Alum. heads......what flow rate would you recommend? ---- And regards to Pistons, Forged?? Hyper...? or cast??

Not sure which car the engine will go in for sure, I have another 56 BA (4-door) that my son has hinted at reviving (A TON of WORK)....so, it will likely just replace the current 327. As for my driving habits..... mostly local cruise ins, drives out to mountains, 120+ mile weekend trips, just out enjoying the car, but it being a 4-speed, i like to FEEL the Power when taking out from a red light....you know....going thru the gears. then it's back down to a good cruise.

markm
09-21-2016, 06:05 AM
Unless you want a trans change too I would stick with 3.08 gears. I have a 4 speed Z28 with 3.42 gears and it talks to me at 75 mph. Forged is always better I have seen a few failures on the Hyper. A friend of mine owns a machine shop and he always recommends them if budget allows.

Bluegrass Trifive
09-21-2016, 09:52 AM
I've had the good fortune to build dozens of 400 SBC based engines over the years. Your stock 4 bolt main block will serve you well as long as the core shift is low as they had some trouble with that. I'd sonic test it on the thrust sides of the cylinders and watch for it being more than .200 or so wall thickness. The 4 bolt blocks will do fine as long as you keep the compression down below the 11.00-1.0 range and the power below 500 hp. After that and things start to move around a bit. If either of those are planned higher I'd go with a 2 bolt block converted to 4 bolt splayed caps. In that configuration I've successfully ran up as high as 13.00-1.0 and 600 hp. Beyond that and cylinder troubles can and do happen. As far as heads are concerned I'd look at AFR's stuff, around the 200cc range CNC ported if your budget allows. As for as the cam is concerned I'd look at a hydraulic roller from either Comp Cams or Erson. Understand yourself what your looking for in drivability and give them a call. Good rods and pistons are very reasonable priced these days Wiseco pistons and Callies rods will serve you well. With balancing being required I'd look seriously into buying a rotating assembly meaning crank rods and pistons already balanced. I just finished a 408 LS with my son and we had tons of fun and he learned a lot. Good luck enjoy your build!
Hello All,

My Son has been after me for awhile now for us to do a "father/son" engine build from my stock pile of parts, So I would like some feedback on what i have in mind....and or possible suggestions. The engine will likely go in my 56 at some point and as currently, will remain a weekend driver (No Drag Strip).... like a lot of others, i want all the POWER to the wheels i can get from red light to red light and still burn pump gas. As much as i really like the current 327.....I've always been told that MORE Cubic inches is the way to go.

Looking for low RPM power....not pushing RPM's thru roof.

400 small block (4 bolt main) bored 30 over ---- Also have same block standard bore too.
Crank suggestions--?? thinking of having it stroked to 3.875 --- or should leave it?
5.7" or 6.0" rods?
Piston type?? (Hyp....Forg....flat....dome)
Aluminum Heads -- Any specific recommendations, esp flow rate?? --Also-- I have a good set of #186 heads i could use, but was saving those to replace the old 461 double humps on the 327.
Cam type & size
Intake -- Have a Edlebrock Torker single plane.....but may replace it.
Engine will run a 4-speed tranny & Current Rear End Ratio is 3:08 ...... but i also have 3:36 ---- 3.55-----3:73

Yes, I know 400's have possible block issues and I understand to go with longer rods / crank combo will require machine work. And I have already looked at just buying a crate engine, or Rotating assembly, or even a short block and go from there.....BUT, that's not the direction i want to go at this time.


Thanks,
Ed

Eds56
09-22-2016, 04:47 AM
Good rods and pistons are very reasonable priced these days Wiseco pistons and Callies rods will serve you well. With balancing being required I'd look seriously into buying a rotating assembly

Thank You for the input, What are your thoughts on standard rod length VS. bumping it up to 5.7"?
Also, for my situation....would stroking the crank to 3.875 really make that much of a difference.....other than a lighter wallet?

If my block, crank & rods do NOT check out ok at the machine shop, then i'll look into a rotating assembly....just have to see what it yields first.

Rick_L
09-22-2016, 06:08 AM
Rod length is not a really big factor. The biggest thing is that a long rod shortens the piston and gives you a lighter assembly - but not by much. Too long on the rod and the piston pin is up in the oil ring groove and that requires some special parts. Stick with simple on this. If you replace the rods, slightly long is the way to go to keep it simple.

The 3.875 stroke gets you about 14 cubic inches - and about 15-20 hp with most combinations. And more expense, along with potential clearance problems (which can be solved with the right parts).

markm
09-22-2016, 06:53 AM
I would stick with a stock stroke and concentrate on cylinder heads is $$$$ are a factor.

Maddog
09-22-2016, 07:38 AM
I would never keep the stock rods, 5.7" a must do with stock crank.

Bluegrass Trifive
09-22-2016, 06:54 PM
Thank You for the input, What are your thoughts on standard rod length VS. bumping it up to 5.7"?
Also, for my situation....would stroking the crank to 3.875 really make that much of a difference.....other than a lighter wallet?

If my block, crank & rods do NOT check out ok at the machine shop, then i'll look into a rotating assembly....just have to see what it yields first. That's a little bit of a complicated question to answer. The assumption is that you'll buy a set of pistons regardless of the direction you choose to go and bore the block .030 over as 400s typically need it if they have very many miles. In rare cases you might get lucky and make a .005 over. Now you look at the rods, I would for sure change the rod bolts with ARP bolts and resize them, (I'd use a set of 5.700" rods since you're buying pistons anyway) but now you have $200-$250 in a set of pressed pin rods. You can buy a set of Callies I Beams for about $550. Next is the crank, new pistons means rebalance anyway and if you need to grind the crank in my area that's $150 plus $ 200 to balance. A new Scat or K1 4340 Crank is about $700. It's been a few months since I bought a small block rotating assy but the last one I bought cost about $1800 balanced and the Wiseco pistons came with good rings. If you went that route I'd consider the 3.875 stroke and 6" rods as the cost of the rotating assy is the same but... you have to clearance the block and get a small base circle cam to clear the rods, not a big deal. So you can save some $ and use the stock stuff you have if it checks out ok, or spend a little more and make some improvements. If I could only do one or the other I'd spend my money on the heads and cam.

hutchenc
09-22-2016, 10:35 PM
Like everyone has said, get your block checked out first and go from there. On a stock 400 block, I don't think I'd worry about changing the crank stroke and I wouldn't worry about the 4 vs 2 bolt deal...you're not looking to wind it up so it doesn't matter. I'd use the stock crank if it checks out too...going to a 3.875 stroke will not only cost you more, but you'll need to clearance the block, and you might need a special oil pan to clear the counter weights...I did (I have a 420 Dart SHP SBC). You're not looking to wind it high so I'd put in a set of decent I beam rods and hyper pistons...there's no reason to go with forged unless you plan to wind it high or apply forced induction/nitrous (or you plan to do a lot of towing with it...which seems unlikely). Keep in mind that the LS7 Corvette motor used hyper pistons...yeah...it makes 505HP SAE net (likely 600HP gross, maybe a bit more) and your 400 SBC won't come close to that power level. Use some high quality bearings and be done with it. If you don't plan to turn more than 5500 RPM...there's no reason to build a crazy bottom end.

Put your money into heads and the valvetrain. If you really want to max it out, buy a new intake too. That's where you'll make a lot of power. I wouldn't run anything less than a 195/200cc head even on a street-only 400 SBC...a single plane intake like the one you have won't hurt you on the street with that many cubes either so your current manifold, while not the best, is a decent choice if you're looking to save a couple hundred bucks. Read here one intakes: http://www.hotrod.com/articles/19-single-plane-small-block-chevy-intakes-test/

Heads: I'd look at a set of AFR 195's set up for a hyd roller/flat tappet or a set of Profiler 195's (Jeg's brand heads are the same as Profiler's btw). The 200cc Dart SHP heads aren't a bad choice either, but they'd be third behind the others I suggested (they're also cheaper). I think you could easily run 10.5:1 compression with the right cam and heads on the street with 93 octane at sea level. I wouldn't even hesitate to run 10:1 with newer heads. I'm running 11.3:1 on 91 octane at high altitude, btw. Cam...I'd convert to a hyd roller, but that's some extra coin (probably a solid $700 over a new flat tappet cam/lifters) so that's a choice you have to make depending on your budget. A hyd roller will make more power everywhere in the RPM range than an equal flat tappet...but they cost more to install on an old block so that's the trade-off. In the end, the power is in the heads more than anywhere else so spend your coin there.

You could make an easy 450 HP (gross) with a mild build in my opinion using the right parts. Also...you'll likely roast your stock rear end with a motor like this so plan ahead.

Eds56
09-23-2016, 10:31 AM
WoW!!! a lot of good info to take in, THANKS

I think for my situation, assuming the Bottom half checks out ok, i would be better off putting any "extra" money available into the Heads / Roller Cam area, instead of worrying with stroking crank, 6" rod and all the block clearance issues.

Anyways, I suspect there should be a "noticeable" power difference between current 30over 327 double hump headed engine changing to 30over 400 w/5.7 rods, roller cam, alum. heads engine, so maybe that'll hold me off for awhile.

I do THANK all of YOU for the input and esp. the specifics to detail.

More to come, after i drop parts off at machine shop.

Eds56
09-26-2016, 04:50 AM
One more Question related to new Alum. head choice-- Angled or Straight plug heads?? ---- Currently running Patriot H8055 headers with my double hump heads.

markm
09-26-2016, 05:59 AM
Straight plug to reap the real benefits of an angle plug you need dome pistons.

JT56
09-26-2016, 09:23 AM
Most good aftermarket heads have a raised exhaust port. Having angle plugs heads help with spark plugs...I would do it.

markm
09-26-2016, 10:47 AM
Over the years I have seen angle plug heads cause as many issues with wires as they solve. To bad OP is so far away I have a std bore 400 block of the 509 casting varity with a std crank I would love to trade for a small journal 327.

JT56
09-26-2016, 11:24 AM
A lot depends on the headers. I had some fuelie heads on this motor first and didn't have an issue at all. Went to a AFR's with straight plug and had issues. New setup has angle and much better

markm
09-26-2016, 12:48 PM
I really try to avoid things like discussing header fitment. I have a set of Hedmen headers on a BBC Camaro that were the envy of my Ford driving friends. Then I installed ARP head bolts, first trip to grinder, then Canfield alum heads with raised EX ports, my header fitment is no longer the envy of the neighborhood.

Additionally, on 55-57 cars especially their are dozens of motor mount setups stock, forward even some setback all of these factors can effect header fitment.

Bluegrass Trifive
09-26-2016, 07:34 PM
One more Question related to new Alum. head choice-- Angled or Straight plug heads?? ---- Currently running Patriot H8055 headers with my double hump heads. Angled plugs, most of the better aluminum heads will be anyway. I've never really had any serious plug wire clearance issues with most common long tube headers and proper wire and loom types.

Rick_L
09-26-2016, 08:01 PM
There's usually a way. Angled plugs on factory heads are not a problem at all with most headers, in fact they have better clearance most of the time than straight plugs. Many of the aftermarket heads move them farther and this becomes a challenge.

hutchenc
09-28-2016, 09:32 PM
I'd check with the mfg myself. I've never had a problem with angle plugs with my Doug's headers...they are a bit tight in spots though. Don't be surprised if you have to run heat sleeves of some type to keep the boots from melting. The worst two plugs to change are on the passenger side...if you leave the battery on the firewall that is.