Doughann

Hi all. Just purchased a 1972 with an original 350 in it. My centre console plate states 350 hp but all my googling only shows the 72 year coming out with 200 hp and 270 hp options. What motor do I have?
Please excuse ignorance, am trying to learn as much as I can though. Cheers

bashcraft

If it's original, you have either a 200 or 270 hp engine. Those console plates can be replaced with any one you want.

Easy Mike

Check the engine ID suffix code on the pad.

Bikespace

This is my favorite site for looking up engine codes, VIN and trim tag codes, etc:

http://corvettec3.ca/

crawfish333

Welcome. If this motor is stock and it is not a LT1, it is the 200 HP motor. There is however, a misconception out there that the 72 has less HP than the 71, which listed its HP as 270 HP. In reality it is the same engine but the government changed the way HP was published. Of course the engine could have been changed, that is easy enough to find out by checking the numbers on the engine.

Stev-o

Check your engine numbers, you may be disappointed...

Doughann

Many thanks. Youre bang on 😀. Its a 200hp but good news is the engine number matches the VIN so matching numbers in that regard. I'm just checking but think the motor has been rebuilt to 1970 specs which was 350hp hence the console plate change.
Has been fun learning about what all the VIN and engine codes mean. Learning heaps. Thanks again

Greg

Crawfish is bang on with this info.
'71 & '72 engines had the same HP, only the yardstick they used to measure with changed. Net hp vs. Gross hp.
Greg

Doughann

Mystery solved.
Engine rebuilt to 1970 specs (about 15 years ago) and now 350 hp (actually 375hp). Hence the console plate change. Still same "original" engine.
Thanks for info on 71 and 72 being same hp, good to know. Cheers

jackson

All good info.

OP
'70 had Very different heads & pistons than low-compression '71 & later ...
... was yours rebuilt to the rather high-compression spec of 1970? Any spark rattle w/ pump gas?
A rebuild w/ small chamber heads and/or hi-comp pistons will increase compression.

A peek under a valve cover will show a head casting number ... that'll identify which sort of heads it has.

Yankeededandy

There must be a difference. Check out the original GM brochures from 1971. It states for the LT-1 330 hp gross and 275 net (the only year by the way, where GM published both numbers, so it's a pretty good reference). In 1972, GM rated it with 255 hp. That's 20 hp less according to my math. So i would guess, the engine specs are different.

Drifting into off topic, but it's an interesting detail, I think.

Martin

crawfish333

https://ateupwithmotor.com/terms-tec...et-horsepower/

L-46man

A CLEAR CASE OF STICKER-SPEED.....If the O/P replaced the aircleaner sticker and the console sticker...does it make you FEEL like you're going faster? LOL

$20 for 75 HP...such a deal!

Run the engine pad numbers....thats 'closer' to the truth. Then look at the casting 'humps' on the end of the heads....that will tell you if it's a big valve head. Then measure the harmonic damper diameter....8" = hi-po 6"- lo-po

unkahal

Doughann

Lol, might invest in a big block console sticker now. Will post more details on mods tonight that were done to 70 specs apparently. Either way, was wrapped with condition of car on delivery last weekend and motor rebuild was just a bonus. Never drive her hard so isn't really an issue if she's 270hp or 375hp (as claimed). Just happy to have a chrome bumper back in the shed 😁😁😁😁

Doughann

Rebuild included, bored .030 over, 11 to 1 forged pistons, SR Torquer heads 67cc chambers, 350hp cam, hydraulic lifters, roller rockers, 750 Holley with sec, ss exhaust. Not hugely into the tech side of motors so not sure how good, bad or indifferent this is but happy it's got a rebuild and runs great.

joewill

good specs... if it has the big valves.
if its original heads in 72 with base motor, then it is not the big valves. so it may not breath as well with those specs
you just have to run the casting numbers and dates under your valve covers. could be replacement heads of course

bashcraft

Sounds like it has the big valves.

jackson

350-375 hp easily doable with the above rebuild

leigh1322

That should run really nice. I think I like the 350HP motor almost as much as the LT-1 I owned for decades.Regardless of who did it, check the distributor tune vs Lars's papers.
Especially if you find it pings or needs octane booster.

Doughann

Thanks for the positive feedback everyone. Is a nice bonus that the engine was upgraded. Didn't really realise until after I got the car so made the purchase even better. I assume the 350+ hp motor would be quite different than the original 1972 270hp to drive