heeelo,
ill just get to the point, i was wondering what the stock, out of the factory hp is of a 1972 402 bbk...its whats in my 72 El Camino. im curious because it just doesnt have much kick to it. now it does have the 3 speed automatic which ive been told robbs alot of potental out of my engine and it is timed right (ive checked many times). i saw a few days ago, a list of engines and the stock hp on a muscle car show on speed vision. but i didnt catch my engine. any help would be great i cant seem to find it anyware
thanks
Rob

the low output 402 put out 240hp i believe

that sounds about in the right ball bark. You can get a lot more out of that baby smile.gif

thanks for the posts...i forgot a little tid bit of info...its an SS engine...does that make any differance

actually im pretty sure that its an SS...but i dont know 4 sure...what is the way to check 4 sure...is there any identifying marks on teh engine anything i can check to make sure?

Didn't they change the way horsepower wat rated in 1972? Because in my original owners manual for my '71 Monte Carlo, it says that the 350 4bbl that I had was 270hp stock. Then in the one for a 1972 model, the 350 4bbl was rated at 145hp??

yeah my manual says the same thing...it says my engine has 240 hp...but the 68 396 has like 350 hp...whats the deal with that. whats the true hp. is it the 240. or did they under rate it for some reason?

The 71-72 402 engine was a low compression {advertised @8.5/1} closer to 8.2/1 motor. '71 listed it at old rating of 330 HP, '72 was 240HP net. I am working with the same block to put my new engine together. Although these were not ultra potent, it still should not be that weak. If this motor is original, it most likely needs a new timing chain. On a low compression motor retarded cam timing will drop performance way down in a hurry. If you don't want to rebuild it, just changing the cam out to a shorter duration/higher lift modern profile and you should pick up a bunch of power. The good thing about this engine is, {at least we have just confirmed this on my block}, the '72 blocks will swallow a 454 rotating assembly.

now it does have the 3 speed automatic which
ive been told robbs alot of potental out of my engineThe automatic transmission does not rob that much "potential" power out of an engine, only a little more than a manual transmission... But maybe an automatic-equipped vehicle might be more likely to have non-performance reanend gear ratios, which would be noticable...


it is timed right (ive checked many times)What specs for the timing? Factory timing specs were specified for lower emissions and as such, not the best specs for performance. To set the timing "to specs" for performance, you'd need an aftermarket cam with those specs... Otherwise, the best timing would be found by trial and error (most likely advanced slightly from the "stock" specs will yield better low-end...)


If the engine is completely "stock", then there might be some better power from the SS engine, but its all mostly bolt-on differences (cam and carb and maybe compression and cylinder heads for the really powerful stock engines), so the potential of yours is the same, just depends on what you want to put in...


I will agree with GRN69CHV, if your motor is old, it might need a tune up or rebuild to realize its original potential...


it says my engine has 240 hp...but the 68 396 has like 350 hp...whats the
deal with that. whats the true hp. is it the 240. or did they under rate it for some reason?The change the methods used for testing sometime in the early 70's, so that and the reduced compression are why your numbers and "spec'd" as lower. There really is probably not that much difference between the two, although the 68 (with higher compression) likely does have slightly more power than a comparable 1972 version (I have no idea if your engine is comparable though...).

I think they use to see how much power the engine made without any accessories, then they changed to add accessories and maybe more similar exhaust to what a car actually had, which is one reason the HP ratings dropped... The factories also had a reputation for fudging the numbers. By 1972, High HP cars were hard to insure, and therefore didn't sell as well. By dropping the HP rating, the car could possibly aviod higher insurance and more people wopuld buy it... Plus, most people interested in High HP would retune the car anyway, and often add stuff like headers, etc... so those lower numbers could have helped the consumer...

Originally posted by GRN69CHV:
the '72 blocks will swallow a 454 rotating assembly. What does that make?
Zac

Bore to 4.25" stock 3.76" crank= 427, 4" 454 crank = 454. For the record, you can overbore to just 4.155" or 4.185" and use Keith Black 361 pistons with the correct '72 open chamber heads and the 454 4" crank to make a 434CI - 440CI engine. I was looking into this, but I have closed chamber heads and my compression would be close to 11/1. So it will not work for me.