crane 168731 cam
#11
That what my set-up is now and the thundbolt 1V that I'm using has no rev limiter. What do you estimate the HP would be with my set-up.I would like to get more HP out of it and still run without a blower or super charger. Thanks Alec
#12
Registered
After some quick calculations, I came up with a compression ratio of 8.39 to 1 assuming the block was not decked and the pistons are .020 in the hole, Fel Pro gaskets .042 thick and 3 cc valve reliefs in the pistons. The good news is, this would make a great engine to put a blower on. The cam is advertised by Crane to be a good blower cam also. Or you can burn any kind of cheap gas you want. Unfortunately this comp. ratio is going to limit your options n/a. Going to a larger cam or retarding your cam will just cause you to lose more cylinder pressure and torque.
Last edited by PatriYacht; 09-10-2008 at 10:27 AM.
#14
I have a thunderbolt 1V without a rev limiter. I had the mpi 502 dist in the carb engine and ran it for one season changed it out when I rebuilt the engine . The 502 mpi has a rev limiter but its built in the ECU not the dist. I replaced the MPI with a carb set up.
#15
Registered
iTrader: (1)
Before vs after
--------------------
ZZ502 cam vs 731
Stock rect heads vs Iron Eagle 308's
stock compression vs less compression ????
Same intake/carb/exhaust
x vs 100hp more ? Don't think so !
What is the piston part# so we can get a close guestimate on compression ?
So far, I have a sneaking suspicion that your 2nd set of mods wherent enough over your 1st set of mods to really gain you anything much.
If your compression works out to 8.75:1 or greater, next time a round I'd run a good single plane intake and a different cam....if looking to go faster.
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BTW: I didn't see if you answered the fuel system questions I asked and what you are running for total timing. If you have, please excuse me.
--------------------
ZZ502 cam vs 731
Stock rect heads vs Iron Eagle 308's
stock compression vs less compression ????
Same intake/carb/exhaust
x vs 100hp more ? Don't think so !
What is the piston part# so we can get a close guestimate on compression ?
So far, I have a sneaking suspicion that your 2nd set of mods wherent enough over your 1st set of mods to really gain you anything much.
If your compression works out to 8.75:1 or greater, next time a round I'd run a good single plane intake and a different cam....if looking to go faster.
------------------------------------
BTW: I didn't see if you answered the fuel system questions I asked and what you are running for total timing. If you have, please excuse me.
#16
Registered
iTrader: (3)
After some quick calculations, I came up with a compression ratio of 8.39 to 1 assuming the block was not decked and the pistons are .020 in the hole, Fel Pro gaskets .042 thick and 3 cc valve reliefs in the pistons. The good news is, this would make a great engine to put a blower on. The cam is advertised by Crane to be a good blower cam also. Or you can burn any kind of cheap gas you want. Unfortunately this comp. ratio is going to limit your options n/a. Going to a larger cam or retarding your cam will just cause you to lose more cylinder pressure and torque.
#19
Registered
If the compression were higher, say 9.7 or so, I'd recommend going to the 741 cam and a Dart single plane. I'm afraid in this case they will just kill torque. Assuming there is no rev limiter, a small supercharger would be the easiest way to fix this. Otherwise complete disassembly, small dome pistons, deck the block. Do the math to get a real C.R. It may also require milling the heads and thinner head gaskets. My 548's with small dome pistons and decked blocks only came to 10.0 to 1 and I'm compressing almost 10 percent more into the same size space.