Topic: age old question - rebuild or crate engine
in Forum: C3 Engines
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What would be the cost of a good rebuild on an L82 engine - I have the engine. Not looking to create a road warrior, just want to let breath wild and free and maybe bump up the compression a little.
I considered a crate engine. But while I can match the hp for about $3k it seems I'm up to about $5k to get all the niceties in an L82 (forged steel crank, forged pistons, etc.).

As it once looked and hopefully will again
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Vince, the recent rebuild of the original L82 in my '73 ran just under $3k. Bored .030" over, slight grind to existing forged crank, new forged pistons and cam. The toughest part was finding an L82 cam supplier that my builder would work with. We finally ended up having one ground by Crower to the original specs. Dyno'd two weeks ago, 310hp/360tq (at the crank). Back in the car and well worth the $$ to keep it as original as possible without going crazy to look for NOS GM internals. Good luck with whatever you choose. If you do go crate motor, make sure you hold on to your original.
John Sigmund

valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member

Duct tape is the new Black !!
Vman, thanks for the reply. That's exactly the kind of info I was looking for. I'll add in that if I avoid the crate engine route I won't have to store the original engine in the basement which will help maintain the relations with the other owner of the house. It's just a matter of time before she finds my collection of original parts like the push rods and rocker arms from when I put in roller tip rockers, the original radio/cassette deck (hey, at least it wasn't 8 track), the 8 track holder insert from the glove compartment (what were they thinking), etc. etc.


As it once looked and hopefully will again
Vman, PS, were those hp and torque numbers at the rear wheels?

As it once looked and hopefully will again
Vince, those numbers were at the crank at 5200 RPM. I believe the original '73 L82 factory specs were 250HP/350TQ at the rear wheels. I was expecting the HP jump based on the crank numbers, didn't know exactly what to expect on the TQ numbers. My builder was impressed by the numbers and he stated that the new forged pistons were much lighter than the originals so he expected the motor to run much better at higher RPM's. One last note is that we re-used the original forged L82 connecting rods. Good luck if you rebuild, make sure you find someone that will stay away from decking the block and preserve your original engine pad !!
John Sigmund

valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member

Duct tape is the new Black !!
Vman, thanks again. That gives me a good idea of what to compare things to then when assessing against the crate engines.

As it once looked and hopefully will again
Vince, good luck which ever way you decide to go. A bit of full disclosure on my dyno run, numbers were made with my original Rochester Qjet, original cast iron intake and original distributor. The only non stock items during the dyno were their long tube headers. Their dyno unit was not set up for my stock exhaust manifolds.
|UPDATED|11/9/2016 3:50:44 PM (AZT)|/UPDATED|
|UPDATED|11/9/2016 3:50:44 PM (AZT)|/UPDATED|
John Sigmund

valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member

Duct tape is the new Black !!
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Overland Park, KS - USA
Joined: 7/9/2003
Posts: 914
Vette(s): 1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.
2023 Accelerate Yellow HTC Stingray
I spent about $2,500 on my L82 rebuild. Bored .030" over, aligned bored, decked the block just enuf to true it up and maintain the VIN stamping, new TRW 11:1 pistons (gives 10:1 compression with the L82 heads) , and a mild roller cam. I did the disassembly and assembly. Still need to measure for the new pushrods and get them. Had the valve covers polished.
One advantage to a crate motor is it comes with a three year warranty.
One advantage to a crate motor is it comes with a three year warranty.
1973 L-82 4 spd
Thanks for the additional input. My thought is to use tri-y's ultimately as from my reading they are likely the best option for a relatively stock L82 which hits max hp around 5200 RPM.

As it once looked and hopefully will again
That sounds pretty reasonable overall and I do like the idea of a roller cam. Of course, I'd have to add labor as I don't plan on doing it myself - just don't want to wait the time I know it would take me to do it.

As it once looked and hopefully will again
in Forum: C3 Engines
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