Preparing to pull trigger on crate engine, T5 conversion
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?





That T5 will be just fine, you're going to love 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..
Last edited by derekderek; Jul 12, 2018 at 08:50 PM.
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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
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. .
I love it in my 69 L46, the M21 ill never go into the car again :-))
Patient in the OR:
Patient being prepped for surgery:
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...
Last edited by C369GS; Jul 20, 2018 at 04:01 PM.
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?).
Last edited by C369GS; Jul 21, 2018 at 12:53 PM.












