Comparison Cosi's to GSC S1's Evo IX
bunch of bangwagoners in here....if you read anything on cams or talk to the guys at gsc, if you have an upgraded turbo you should got s2s. if you have stock turbo and plan on leavin it that way go s1s. so its not a big suprise that the cossie cams out performed a cam that wasnt intended for you setup
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well, im no bandwagoner.... i picked up the S1's because of the performance they seem to give people.... The car felt good with them in there, but its a whole different car with the cosi's in. Not just spool up, but regular driving as well. There id assume the S1's should be on the same floor as the Cosi's because the turbo isnt even in boost. The car just feels smoother. I wish i could of dyno'd the cosi to s1 on stock turbo.... i did however dyno the s1 to stock cams. I only picked up about 15 to 20hp up top at most. Otherwise my powerband was almost the same with only a slight gain in HP throughout the band. In my car on the stock turbo, the S1's just did not do what i expected. They did make the car feel better, just not a whole lot more powerful. I went from 278hp uncorrected to about 290ish.
I also thought the S1's were good up to a 30R turbo
I also thought the S1's were good up to a 30R turbo
Last edited by bigric09; Sep 30, 2007 at 11:26 AM.
bunch of bangwagoners in here....if you read anything on cams or talk to the guys at gsc, if you have an upgraded turbo you should got s2s. if you have stock turbo and plan on leavin it that way go s1s. so its not a big suprise that the cossie cams out performed a cam that wasnt intended for you setup
You realize that the extra valve overlap you get on the s2's would make only a slight spool difference. Look at the mans chart and you'll realize that the cossie's are far superior. So I dont think you read anything cams and you need to jump off the gsc bandwagon, bandwagoner.
not callin you a bandwagoner eric just the guys that like to come in and jump on the train
im glad you have better results with the cossies. im not set to stay with any part so...im glad your car is putting out more powaa
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me too lol....
what got me surprised was the spool up. The spool up with my 20G is what i expected with the S1's and i figured the cosi's would do the same thing, just give me a bit better torque..... and i was floored when i looked at the first trace graph, i immediately pulled up my prior S1 run with the 20G and i was astonished at the difference in spool. HP and TQ is nice believe me, but the spool is what i just did not expect
what got me surprised was the spool up. The spool up with my 20G is what i expected with the S1's and i figured the cosi's would do the same thing, just give me a bit better torque..... and i was floored when i looked at the first trace graph, i immediately pulled up my prior S1 run with the 20G and i was astonished at the difference in spool. HP and TQ is nice believe me, but the spool is what i just did not expect
It really varies by cars as well
On my tuning day, one evo 9 mr had cossie cam and meth tune with jestr and he made 365 whp with 340 tq on spool around 3500~3600rpm ish.
I only had basic bolt on with s1's and I made 350whp and 340tq with about the same spool and the power curve was on the money, super smooth.
The owner was a bit upset cause he was expecting at least 380ish hp, while I was pretty happy with mine...and really made me feel that s1's worked for me.
I agree, with a bigger turbo set up, S2's could have worked better for you.
Thanks for the comparison
On my tuning day, one evo 9 mr had cossie cam and meth tune with jestr and he made 365 whp with 340 tq on spool around 3500~3600rpm ish.
I only had basic bolt on with s1's and I made 350whp and 340tq with about the same spool and the power curve was on the money, super smooth.
The owner was a bit upset cause he was expecting at least 380ish hp, while I was pretty happy with mine...and really made me feel that s1's worked for me.
I agree, with a bigger turbo set up, S2's could have worked better for you.
Thanks for the comparison
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my buddy with S1's made 375 hp which is why i bought mine expecting this big gain.... and it just didnt happen. If i can find my stock to S1 graph comparison, i will post that. You will see what i gained and where.... they just didnt do well in my car i was sorry to find out. Its better now obviously, i was just expecting more from those cams.
Meh, i would only compare the M2 - S2's, not S1's. Numbers alone the cosi is more aggressive without a butt dyno. If you have a stock turbo and DD the car, S1's FTW. If you have a gt30ish or higher, S2's will make it that much sweeter.
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all i have is a 20G9-5, if the S1's are suppose to be good up to a GT30, im pretty sure im within the area of tolerance 
.... BTW, the graph above is stock cams stock turbo compared to stock turbo S1's
does it make sense that my cosi's spool with a 20G the same way the S1's spool with the stock turbo ?
.... BTW, the graph above is stock cams stock turbo compared to stock turbo S1'sdoes it make sense that my cosi's spool with a 20G the same way the S1's spool with the stock turbo ?
Last edited by bigric09; Sep 30, 2007 at 01:33 PM.
this is wierd, on the same dyno, one of my friends made 397 whp on 100 oct and a 20glt with cossies then another with a 20glt and the same mods on 100 oct made 407whp with the gsc's