My motor is approx 10.5:1 compression (I think)
CNC Machined L98 heads (191cc intake and 2.00/1.57 valves)
Miniram
52mm TB
1-3/4" primary Long tubes
2-3/4" dual exhaust (not cats)
6spd with the 3.45 gears
Is it worth the effort to swap cams? What will the newer cam give me as opposed to my current ZZ9? also what might I lose from swapping?
Jeff, comparing my dyno graphs between a 220/230 and my current 230/238 there is a noticable movement in the power curve upwards. Basically, rather than having 350-380 rwtq at 2800-3000 rpms, I now have it closer to 3400 rpms. I am getting better track times in both ET and MPH with the bigger cam. On the street, it drives quite nice as well.
Considering mine is on 398 CID and yours is on 355/357, the changes will probably be similar if you swapped to the Comp cam listed.
I bet someone with desktop dyno would be able to give you more precisely how much different the cams would be. I would say your power band will move up anywhere from 400-600 rpm, but that s just a guess.
The Cam Motion would be a custom grind.. when I called them back to ask what type of gains they said around 1 mph in the 1/4. I am not goign to swap cams for 1 mph.. not worth it to me.. now if I needed to pull the motor apart for something else, then maybe..
I also called TPIS about the ZZ409 and it was basically the same thing. I thin I will stick with the ZZ9 for another year and see how it runs next year, since I am replacing the Centerforce 34# flywheel and clutch with an Aluminum flywheel and new clutch.
Chris, you are saying that you had 350—380 rwtq at 2800—3000 rpm and after changing cams your peak tq moved to 3400 rpm. What happened to your torque itself, did you get more tq? Also, at what rpm do you have max hp compared to the cam you used before? How high is you hp without nitrous? A friend of mine tested my next move to 408ci with my ZZ9 --1.6 RR 212/226@.514/.555 and his EAP showed max 455hp and 465tq. This is not very much for a 408ci, so I was thinking also in changing cams.
I know that you recommended a few weeks ago I should use the comp cam 305 because it had a better idle than the 306.
Jeff
I also called TPIS and asked which cam would be better a ZZ9 with 1.6 RR or the ZZ409. He said using 1.6 RR would be about the same and I would not have to buy the ZZ409 for better performance!!
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