Preparing to pull trigger on crate engine, T5 conversion
 

I am close to pulling the trigger on replacing my non-matching motor (that's blowing oil out of the left cylinder bank) and my 4-speed transmission. Before I do, I wanted to lay out my plan here and see if anyone could highlight anything I've missed. I have researched the forum and read any threads I could find on the T5 conversion, so that's gone into the formulation of the plan. I also intend to tear down the existing motor to see if the oil smoke issue is a small fix, but I'm not expecting that to be the case. So, here's the plan:

Starting point = 1969 L-46 Coupe 4-speed car with 3.70 gear ratio. Non-matching motor that appears to be era-correct but is likely a 400ci truck motor that's been lightly built.

Engine (if needed) - replace existing motor with GM Performance SP 350/357 Base Engine. Re-use existing Edelbrock heads, intake, and carburetor. Re-use existing Flowmaster headers and Mallory ignition components. I'm aware that peak torque for this engine exceeds what a WC T5 is rated to handle, but I don't race the car at all or bang gears as a general rule.

Transmission - I've been talking to Anaheim Gear as a result of an eBay listing they had. They will provide a WC T5 rebuilt to 13-52-176 ratios and dyno test it for $1500.00 plus $145.00 shipping, or about half the cost of a Tremec package from Zip Corvette. I plan to reuse my existing bell housing and mechanical clutch. They will send it with the Camaro V-8 tail shaft. We'll fabricate the shifter offset as shown by one of the posters in the T5 threads here on the forum. I have a local shop that we use for some of our 4x4 builds that can shorten my driveshaft and we have the ability to modify the transmission cross-member. They offer a 1-year warranty with a 2-year installation window, so that provides a level of confidence that they aren't sending out junk.

Have I missed any major considerations and does this seem like a reasonable plan?

I may be confused here but just checking, do the Edelbrock heads you have drop-in for the Vortec heads that the crate motor comes with? I thought there was something different about Vortec coolant flow.

You're right. I won't actually need to reuse the Edelbrock heads with that engine. Just the intake, if that's compatible. I'll look into that before I order the engine if it gets that far.

I would get a ZZ shortblock #12561723. Then swap over your stuff. That shortblock has better internals.

if you dont have an H or x pipe add that to the list....it will add low end torque. did you check all the trans ratios to make sure they hit the sweet spot with your 3.70?

That T5 will be just fine, you're going to love it.

Yes, we went over the ratios. When I order the transmission, I'll make sure they are sending the -176 configuration or very close to it.

For the exhaust, I just have duals all the way back. That's how I was able to tell that the current motor is burning oil only on the left cylinder bank. Once I get it back up on the lift we can see what's involved in doing an X-pipe since we have the bender, torches, and welding gear in the shop as well as extra exhaust tubing..

If you have a 400, maybe just get it rebuilt. 406 us a bit more displacement than 355. What eddy heads? Just checked car-part.com. these guys have 3 reman 88-92 camaro trannys. Worth looking jnto. https://www.zumbrotadrivetrain.com

or a shp dart shortblock

I'm going to order the 1352-176 T5 from Anaheim Gear on Monday. They confirmed the model number and they are almost $1K less expensive than Zumbrota Drivetrain, partly because they don't have a $400.00 core charge and I don't have a core to give.

I believe the Edelbrock heads are the 210 aluminum heads but I won't know until we pull the motor apart and check the numbers. There is a note in the file from the previous owner saying

The 205 appears to be a Ford series number, so I'll need to confirm exactly which ones they are. All the Edelbrock stuff was done about 10 years ago. If the ZZ short block will allow me to reuse all the Edelbrock pieces (and they are in good shape), that option could save me a lot of money. I'll just have to wait until we can see what everything looks like before making that decision.

You will love it !!

I installed a 1352-176 in my 69 L46, 3.70 rear. And I love it.
@60 mph I now have 1650rpm !!

Sounds like youll need to find the model # of the heads first.
Edlelbrock has come out with a bunch of packages over the yrs, some decent, some lame.
Rebuilding your 400 if it has one left would be the route id take. Would be real hard to deal with a 350 after having the 400; nothing fancy needed unless youre spinning it up high which you arent ..
x2 on the 5 spd it will be a big plus. .

And so it starts - I ordered the transmission yesterday from Anaheim Gear. They have more in hand if anyone else is looking for a 1352-176. Price for a rebuilt, dyno-tested unit is $1550.00, plus shipping. They confirmed the gearing and verified it will come with the Camaro tail shaft. Friday, I'll move the Corvette to my shop and we'll start pulling the motor and 4-speed. I'm going to leave open the option of going the ZZ4 bottom-end route, depending on what we find when the 400 is apart.

Good luck with the project, you will love it :- )
I love it in my 69 L46, the M21 ill never go into the car again :-))

I brought the Corvette to the shop today and we've started the project.

Patient in the OR:
https://cimg2.ibsrv.net/gimg/www.cor...e224103b3b.jpg

https://cimg6.ibsrv.net/gimg/www.cor...949ca53ae1.jpg


https://cimg5.ibsrv.net/gimg/www.cor...006a3fa18e.jpg

https://cimg8.ibsrv.net/gimg/www.cor...b535c508e5.jpg

https://cimg7.ibsrv.net/gimg/www.cor...6737351cfe.jpg

Patient being prepped for surgery:

https://cimg0.ibsrv.net/gimg/www.cor...8ad3941e2d.jpg

With the hood off and some of the dress-up pieces removed, I had a better view of the numbers from the Edelbrock manifold and heads. The manifold is a 7501 and the heads are 6089 (since superseded to 60899, from what I can tell). More to come...

Looking good :- )

Here's a shot of the numbers on the front of the motor. Can anyone tell from these what this motor was in originally?

https://cimg3.ibsrv.net/gimg/www.cor...1dfa66255b.jpg

If I've decoded it correctly, it appears to be a 400 from a 1972 Caprice, production unit 143348. Engine built in Tonawanda October 20 (1971?).

Dont see no pic.

I just refreshed the page and I can see it so I don't have any idea what's wrong. But here are the numbers:

12S143348 T1020CKP

I am looking forward to your review once you have your new motor and transmission. Good Luck!