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Still in the beginning of this swap, but these are the apparent considerations:

it looks like the oil pan will need some mods to clear the steering linkage. Hopefully only to the front face of the sump. And the engine mounts are farther to the rear on the OHC block vs. the 250, so some adapters can be made to solve that...if the accessory drive assy forward of the pass side mount doesn't interfere, all that should work. Overall length is still a question; even with the shorter 69 water pump installed and a flex fan replacing the original, there will be very little clearance there.

Stay tuned for more details!
 

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Discussion Starter #22
Ok, got the overall length of the engine down to 32 5/8" so we should now clear the radiator without a problem. Time now to sit down with some cardboard and make some templates for the motor mount adapters.
 

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Discussion Starter #24
I'm beginning to see why this engine was pulled. Took the cam cover off and discovered that it's got the wrong cam in it as well as having a dead lobe... Time to pull the head and investigate further.
 

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I put a sbc in an 82 s10 4x4,had to put the radiator,(4 core w/chevette tanks) in front of the core support. is it possible to do on your nova?
 

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Discussion Starter #27 (Edited)
I put a sbc in an 82 s10 4x4,had to put the radiator,(4 core w/chevette tanks) in front of the core support. is it possible to do on your nova?
I don’t think that would be possible in this car. The hood latch support is right in front of the radiator. I’m pretty confident that after installing the shorter ‘69 pump I’ve got enough clearance from front to back.

Just completed the motor mount jig that mirrors the angles of the mount supports in the car. With this, I can hold the mounts in the correct position to fabricate adapter plates for the engine.
 

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Discussion Starter #28
So it had the wrong cam... no biggie. I was able to finally verify today that it does have the 10.5:1 cylinder head on it. Going to pull the head this weekend and take a look at the rotating assembly to make sure it’s all kosher. Updates to follow
 

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Cool thread. My Dad bought a OHC 6 '67 Tempest on the day I was born. He said the car ran really well. It was not a Sprint motor. If you need some old OHC 6 emblems, I think I have a set. I believe I have the custom emblems too. Your car will definitely be custom. Curious what that motor weighs. Does it have an aluminum head?
 

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Discussion Starter #32
Finally got everything torn down and gained a ton of new knowledge about these “cammers”. The crank may be based on a Chevy inline 6, but it must be just loosely... It does share the Chevy bolt pattern on the rear of the crank, but that’s where the similarities end. The snout is not your typical 2 1/2” but rather 2 3/8”. The flywheel has 166 teeth instead of 168. While the 166 tooth count is typical for Pontiac, the bolt pattern and snout size are not, it is truly unique to this engine. The starter pictured below is a 96 corvette unit mated with a typical 168 tooth Chevy flexplate. It is spaced off of the bottom of the block a total of 13/64” in order to make the teeth mesh so I’ll need a piece of aluminum machined instead of using a pile of shims. The area inside the green tape on the oil pan is what will need to removed to clear the drag link and with the Vette starter being so much smaller, it too will clear the steering. I’m on the hunt now for someone with a lathe to make a spacer ring to take up the difference in size between the crank and flexplate center hole. Now that the block is empty I can flip it back over and start working on building the motor mount adapters. More to come...
 

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I was thinking about you guys ........ glad to see your making some progress ...... :cool:

Keep at it ...... we're watching .. :yes:
 

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Another surprise once the head was off--this engine has been over-bored .060! Main and rod bearings were standard size replacements, rod bearings being the same as a late 327 or 350. Haven't mic'ed the crank yet but it looks good enough to polish, then fit either standard or .001 bearings depending on clearance. It has forged rods, forged pistons, and the crank is nodular iron, all as OE. Fel-Pro gasket set should be in hand by tomorrow, we're needing to determine the head gasket compressed thickness before the head goes to the machine shop, in case it needs a slight shave. It is critical to maintain the same crank to cam centerline distance because valve timing will be affected if this varies from OE spec. Head gasket as found was a GM shim steel part; sealing looked good so we're not too concerned about untrue surfaces, but will straightedge-feeler gauge the block deck. The machine shop we found is familiar with this beast, so they'll know the right things to do as far as the valve job is concerned. If the block bore is tapered or out of round by too much, we may have a ring seating problem...as it really can't be bored again. There was very little ridge at the top, mostly just carbon, so we may be lucky with that.

More later!
 

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Discussion Starter #35
Making more progress

The head is at the machine shop getting a valve job and hardened seats. We are about to hit the block with a ridge reamer and hone, then polish up the crank. I was able to solve the issue of the flexplate. Took a piece of 2 1/2" exhaust pipe and made a poor-man's lathe to solve the issue of the crank being too small to center up the flexplate.

Also started working on the motor mount adapter plates. Got everything cut out and mocked up in cardboard, then transferred to 1/4" plate steel and designed in CAD. A friend of mine has a water jet machine so the cuts will be perfect! Now comes the hardest part... waiting on the machine shop!

Cheers
 

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Any updates, I just bought a '68 250 cu inch OHC, 175hp six...might try to find a first gen to put it in...
 

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Hi Greg ...

I was kinda wondering the same thing .... we haven't gotten any up-dates on this build. ?

You should consider a 3rd gen Nova ...... alittle more room , maybe .....

see - ya
 

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You might want to make sure you have hood clearance in that Chevy II. Those OHC 6s are tall in the front with that cam belt cover.

I have a custom built low-deck 292 on a motor stand that I intended to throw into my Chevelle, but at one point I looked at '67 Tempest 2-door "post" that was a former OHC-6 car that was running a 305 V8 at the time I looked at it. I thought it would make a nice recipient for the 292, given that the cammer was long gone.
 

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? ?

"low deck -- 292" .
 
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