Printable View
My son bougth a rebuilt 396 that has been stored for 10-15 years.
Block casting number: 3916323, 060 bore
Heads: 3964291 108cc?
Cam: Comp Cam 11-430-8 (10) Grid number 280HR
Pistons: TRW L-2287
Rods: Manley 14060
It seems that it has prox 11,88 comp ratio but the cam specs says it for 9,5:1 ratio.
The engine has not been started.
What do you guys think?
Chevy BB is all new to us..
Thanks! :)
what is the octane rating of fuels in your area.?
98 octane..Quote:
Originally Posted by HOSS429
It's definitely NOT 9.5 compression, your pretty vlose with your 11.5 + guess.
If you have 100 octane gas, your OK, but not good for daily driver with low octane fuel.:(
if after you run it you find your compression a bit high retard the timing a bit or even use two head gaskets . ( double stack ) . i`ve done that without problems .. and even the factory once did it .. wish i could get 98
Quote:
Originally Posted by Geezer2
CC recomends 9,5:1 for the cam.
How will it work with 11,8?
It's not a daily driver.
Weekends only:toocool:
With a good intake and headers you'll be fine. Most likely CC reccomendation is for 9.5 and higher compression. That much cam in an 8-1 engine would be terrible on the low end.:D
the problem with running too small of a cam in an engine with alot of compression is detonation. After searching for this piston I came up with a 47.1 cc dome or a 43.1 cc dome. Not sure which one you have but they are both under the same general part number. With the 43 cc, zero deck, and .040 gasket, I came up with 11.89 CR , and with the 47cc dome I came up with 12.49CR!! I think with 11.8 CR you are right on the verge of needing to run race gas, 98 is awesome but 110 sounds better. I would be weary of running a cam with only 224 degrees @ .050 lift. Sounds very small for a 12 to 1 engine. If you are dead set on using this motor I would use 110 octane, and retard the timing alot. If you hear detonation I would get off the gas real quick, cause it don't take long for a piston to melt under these conditions. What will the motor be used for? I would at least shoot for 240 degrees @ .050 on the cam duration. Plus those old magnum cams are outdated, much more potential with an Extreme Energy cam!!
Run a bigger cam!!