As far as I know, the intake manifolds where always machined at an angle to keep the carburetor kind of level, so that is not the best reference point for pinion angle. With injection, it doesn't matter.
As far as I know, the intake manifolds where always machined at an angle to keep the carburetor kind of level, so that is not the best reference point for pinion angle. With injection, it doesn't matter.
Last edited by 55 Rescue Dog; 08-25-2016 at 05:45 PM.
Most intake manifolds have the carb flange machined at 4 degrees down in front. This puts the carb flange level when the engine is at the usual 4 degree OEM down in back engine installation.
But a visual inspection of the photo shows that hutch's manifold is level with the engine as he said. This is often seen on manifolds that are designed to go in a race car where the engine is level.
The engine's oil drainback is designed around a 4 degree down in back installation. That's a good thing but a level installation is not a bad thing for oil drainback if you're concerned about it. A race engine often has the drainback modified to keep the drainback oil off the crank - or a dry sump is used which mostly eliminates any of that.
But a bigger thing is the way the transmission fits the tunnel, which is a big part of the back and forth in this thread, this done in conjunction with setting the pinion angle.
I'm an advocate of keeping the original engine installation angle, but sometimes you can't. Seems like we have a discrepancy here, and it has to be overcome some way.
OK, so I measured the frame and it's at about 1.5 degrees sloping forward. I do plan to lower the rear end by at least one inch however...maybe two inches. So that would decrease that angle, by how much I'm not sure.
I double-checked the engine angle on the front crank pulley and on the head and it is indeed the same so that carb pad is flat for sure. Measured 5.5 degrees everywhere (well, 84.5 on the crank pulley).
So...I can probably shim up the rear of the trans a bit to get the angle closer to 4 degrees.
Lazlo...are you sure on that 7/8" per degree? That would mean that I need to raise my trans close to 2 inches...that seems really excessive (and I don't think there's nearly that much room either).
Last edited by hutchenc; 08-25-2016 at 07:54 PM.
I figured your engine was too low.Originally Posted by hutchenc
Your engine is really sitting at 7 degrees to the frame or 1.5 degrees too low. Like I said, I'm not sure how much to shim it per degree, but if I knew the distance from the engine mount to the tranny mount I could tell you. I'm guessing it's around 48" so that would be .84" per degree, or 1.26" to get to 5.5 degrees.
I would lift the tranny and see how high it will go, then decide where to put it from there.
56 Nomad, Ramjet 502, Viper 6-speed T56, C4 Corvette front and rear suspension
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56 Chevy 2-door BelAir sedan
56 Chevy 210 4-door sedan
57 Chevy 210 4-door sedan
1962 327/340HP Corvette
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If it's a 4L60E = 22.5" Block Flange to mount CL. SBC center bolt hole (triangle pattern) for mount to block flange = 15.95 +/- so it's 38.45" pivot to trans mount. 1° = .6711" I'm doing that from memory and guessing on trans. 4L80E is 7-7/8" longer so it goes up to .808"I figured your engine was too low.
I would lift the tranny and see how high it will go, then decide where to put it from there.
So, it looks as though you have a 4 speed by the images provided. Standard Bell Housing depth is 6.3" and the flange to mount CL is 14.2" - 1° = .636" If I am wrong on trans type, let me know and I can plug it in.
Last edited by NickP; 08-26-2016 at 11:21 AM.
Nick...it is a Muncie yeah.
So, mostly good news. I was able to lift the tranny by 3/4" and it put my motor at 4 degrees on the money and I was able to get the driver's side valve cover on (using a different cover, that I intended to use anyhow)!
Bad news is that I still can't get the passenger cover on. The tall ones just aren't gonna work. I'm confident a set of shorter ones will be fine. These have the angle at the edge, but it's still too tall to fit on the passenger side.
Anyone want to buy these covers? They're pristine...never used, just mounted for mock up. They aren't even cut for PCV or breathers yet. $200 plus the ride if anyone wants them.
Wish those fit a LS lol. They are very nice looking covers!!!!
Hmmmm, B4 you go and do anything, by how much does the cover not work now? 1/4", 3/8" or way more? If memory serves me, and Laszlo, jump in here to either dispel my thought process or confirm, the steel motor mount is built with a tube that the GM or other lays over and the 7/16" bolt secures. If, you were to cut 3/8" of the tube from the rear (firewall side) and moved it to the front (some welding required), re-drill the trans crossmember by 3/8" forward (or slot if possible), would that get you the space needed?So, mostly good news. I was able to lift the tranny by 3/4" and it put my motor at 4 degrees on the money and I was able to get the driver's side valve cover on (using a different cover, that I intended to use anyhow)!
Bad news is that I still can't get the passenger cover on. The tall ones just aren't gonna work. I'm confident a set of shorter ones will be fine. These have the angle at the edge, but it's still too tall to fit on the passenger side.
Anyone want to buy these covers? They're pristine...never used, just mounted for mock up. They aren't even cut for PCV or breathers yet. $200 plus the ride if anyone wants them.
I honestly can't tell how much space I need...I'm thinking it's close to a half inch (vertically) which I can get by moving to a short valve covers. I'm not real thrilled about the idea of modifying the motor mounts at this point vs. changing valve covers. Just gotta find a set that fits.
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