trying to add HP... need help!
trying to add HP... need help! Okay so i bought this 2002 z28 camaro that has a LQ9 6L.
The car made about 440whp and 400wtq on the Dyno.
The car has a comp cams 232/234 .595"/.598" cam with 5.3L heads that have been ported and polished (im not sure how much). The car has a Fast 92/92 setup with 43lb injectors. The car also has roughly 12:1 compression, or so im told.
Im looking to make closer to 500whp, so what is my weakest link? Id like to keep the heads if thats at all possible to save money, i was thinking i may need a bigger cam. I was also thinking about going the 408 route. What do you guys think?
The car made about 440whp and 400wtq on the Dyno.
The car has a comp cams 232/234 .595"/.598" cam with 5.3L heads that have been ported and polished (im not sure how much). The car has a Fast 92/92 setup with 43lb injectors. The car also has roughly 12:1 compression, or so im told.
Im looking to make closer to 500whp, so what is my weakest link? Id like to keep the heads if thats at all possible to save money, i was thinking i may need a bigger cam. I was also thinking about going the 408 route. What do you guys think?
6SP or A4?
The heads are probably the single greatest choke point.
Because, the FAST 92 should be good enough. And most folks who sniff 500 rwhp are doing so with a cam roughly 10 degrees bigger. So, really, you're only looking at 10-15rwhp out of a camswap. That won't get you there.
It comes down to the heads and the exhaust. If you're running a y-pipe setup or a 1-3/4" headers and weak heads, 440 is pretty good. Swap out the exhaust for true duals, 1-7/8" headers, and some higher flowing heads, and you could probably hit 460-470 before touching the cam. Then the cam could get you up over 480 and now you're in the realm of 500. You have more bore than a 346, so it should be theoretically easier. But still, you have to have all the little things, all the tricks, etc to hit 500.
The heads are probably the single greatest choke point.
Because, the FAST 92 should be good enough. And most folks who sniff 500 rwhp are doing so with a cam roughly 10 degrees bigger. So, really, you're only looking at 10-15rwhp out of a camswap. That won't get you there.
It comes down to the heads and the exhaust. If you're running a y-pipe setup or a 1-3/4" headers and weak heads, 440 is pretty good. Swap out the exhaust for true duals, 1-7/8" headers, and some higher flowing heads, and you could probably hit 460-470 before touching the cam. Then the cam could get you up over 480 and now you're in the realm of 500. You have more bore than a 346, so it should be theoretically easier. But still, you have to have all the little things, all the tricks, etc to hit 500.
6SP or A4?
The heads are probably the single greatest choke point.
Because, the FAST 92 should be good enough. And most folks who sniff 500 rwhp are doing so with a cam roughly 10 degrees bigger. So, really, you're only looking at 10-15rwhp out of a camswap. That won't get you there.
It comes down to the heads and the exhaust. If you're running a y-pipe setup or a 1-3/4" headers and weak heads, 440 is pretty good. Swap out the exhaust for true duals, 1-7/8" headers, and some higher flowing heads, and you could probably hit 460-470 before touching the cam. Then the cam could get you up over 480 and now you're in the realm of 500. You have more bore than a 346, so it should be theoretically easier. But still, you have to have all the little things, all the tricks, etc to hit 500.
The heads are probably the single greatest choke point.
Because, the FAST 92 should be good enough. And most folks who sniff 500 rwhp are doing so with a cam roughly 10 degrees bigger. So, really, you're only looking at 10-15rwhp out of a camswap. That won't get you there.
It comes down to the heads and the exhaust. If you're running a y-pipe setup or a 1-3/4" headers and weak heads, 440 is pretty good. Swap out the exhaust for true duals, 1-7/8" headers, and some higher flowing heads, and you could probably hit 460-470 before touching the cam. Then the cam could get you up over 480 and now you're in the realm of 500. You have more bore than a 346, so it should be theoretically easier. But still, you have to have all the little things, all the tricks, etc to hit 500.
I did some more research and i found that guys with ported 5.3heads are only flowing 270cfm intake. which isnt great since PRC stage 3 heads flow 324cfm. I was planning on going with a larger cam, maybe an MS4 or some form of custom grind. currently the car has stepped headers into 2.5" duals. Im going to swap that out to 1 7/8" headers with 3" true duals.
Also found out the car has 60lb injectors, so i know fuel isnt a problem.
after my research im thinking. new heads +30whp new cam+15whp 408+20whp which should put me right around 500whp
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apparently not. car only dynoed 440whp
well see heres the catch, the car isnt exactly running. I bought the car with a blown motor. The complete bottom end is trashed, which is why im going to a 408 setup. However all of the top end is good and can be repaired and reused. The car made 440whp and 400wtq with its previous setup and ran a best of 13.02s at 116.54mph (i think a driver mod would really improve those times). (based on the mph the car should run 11.5 ish)
Secondly, once im done repairing the engine and achieving my horsepower goals, im going to get a MWC 9" rear with a bunch of their suspension goodies to help it hook/launch straight.
Secondly, once im done repairing the engine and achieving my horsepower goals, im going to get a MWC 9" rear with a bunch of their suspension goodies to help it hook/launch straight.
Last edited by KingPin1094; Mar 23, 2013 at 02:49 PM.