I asked this on the Classic Tech page but I figure this is a better place for it so... I have a 71 Camaro, going to drop in a ZZ4 Crate in the spring and then Supercharge it in the summer with a 142 Weiand Blower. First of all, do you think it will fit under a 2 1/2'' cowl with a small air cleaner (2''), and secondly, Will 9:1 compression cause detonation or will I have to bring back the advance in the distributor (or worse lower the compression). Thanks.
Registered User
Keep that boost low, 4psi should give you a significant performance increase. 6psi would be better still, but with those hyper pistons, you had better keep that thing in tune. They won't like much detonation at all. Keep your timing reasonable, run good gas, and don't get greedy with the boost. Should be a quick sleeper.
Registered User
I once had an '89 Firebird (3rd Gen) with a ZZ3 Crate motor/TFS heads, and a B&M 144 and my advice is:
* FILE FIT THE RINGS!!! The ZZ3/ZZ4 ring gap isn't wide enough. Take the pistons out and file the top ring to .024" - .026". I broke 6 pistons because of this. The extra heat from supercharging causes the ring to swell. If the gap isn't wide enough, the ring will bind in the bore and break the ring land on the piston.
* Mine fit under a 2 1/2" Harwood cowl with a 2" tall filter element in a drop base air cleaner. I think the Weiand 142 is 1/2" - 1" taller than the B&M, but the '71 Camaro may have more room in the base case. A good comparison is a Victor Jr. with a 1" spacer. They are about the same height.
* Keep the boost around 5 psi. I raised it to 7 and gained no power while increasing the chance of detonation.
* At 5 psi and 9/1 compression, you should run about 28 degrees total timing (vacuum advance unhooked, rev'ed to 5,000 rpm).
* If you run the vacuum advance, make sure it ties into the lower intake (below the blower). This way the vacuum advance doesn't work at any boost level.
Mike
* FILE FIT THE RINGS!!! The ZZ3/ZZ4 ring gap isn't wide enough. Take the pistons out and file the top ring to .024" - .026". I broke 6 pistons because of this. The extra heat from supercharging causes the ring to swell. If the gap isn't wide enough, the ring will bind in the bore and break the ring land on the piston.
* Mine fit under a 2 1/2" Harwood cowl with a 2" tall filter element in a drop base air cleaner. I think the Weiand 142 is 1/2" - 1" taller than the B&M, but the '71 Camaro may have more room in the base case. A good comparison is a Victor Jr. with a 1" spacer. They are about the same height.
* Keep the boost around 5 psi. I raised it to 7 and gained no power while increasing the chance of detonation.
* At 5 psi and 9/1 compression, you should run about 28 degrees total timing (vacuum advance unhooked, rev'ed to 5,000 rpm).
* If you run the vacuum advance, make sure it ties into the lower intake (below the blower). This way the vacuum advance doesn't work at any boost level.
Mike