Pump gas cam vs: Compression, Cylinder Pressure, Timing, etc.
05-15-2006, 03:07 PM
#21
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Originally Posted by Pro Stock John
1) I am opposed to traditional split camshafts due to the research I have done.
Originally Posted by Pro Stock John
2) I was thinking higher rpms and some revs, since I didn't think a 8.2:1 348ci LS1 on 93 pump gas would make 700rwhp by 6200 rpms. I guess we will see. Conversely a car making 900rwtq at low rpms might be a monster to hook too....
My best advice for building a fast pump-gas setup is to run compression in the 6:1 or 7:1 area and up the boost.
05-15-2006, 04:26 PM
#22
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Well, Kurt from W2W for one is not advocating traditional splits for a turbo setup, and he seems to be pretty knowledgeable. I admit I think he has a lot of engine dyno experience, which might be why he has certain positions on parts.
05-16-2006, 08:19 AM
#23
Most of the turbo engines that I have fooled with that needed to make power in lower rpm range were all 2 or 3 stage systems. We ran realtive low static compression, around 6.5 or 7 to 1 and then ran high boost numbers. . .around 130PSI. We needed to achieve max power below 5K with 426CID.
05-16-2006, 09:01 PM
#24
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I got a little lost in some of the enigmatic dialog, but as I understand it, a typical DIY turbo installation develops maybe twice the exhaust backpressure as boost, so any valve overlap will cause heavy reversion, thus requiring really short duration cams.
Well engineered, big turbo setups on the other hand can have one-to-one BP/boost ratios, at which point a cam very similar to a good N/A choice for the RPM range may be optimal.
Well engineered, big turbo setups on the other hand can have one-to-one BP/boost ratios, at which point a cam very similar to a good N/A choice for the RPM range may be optimal.
05-17-2006, 11:22 AM
#25
PSJ, for what it's worth, there's a guy out this way that made 760 rw last year with a 346 and a 80mm turbo, If I remember correctly, the cam that he had in his car was just like the turbo cam that speed inc. has listed on their webiste.. I think it's a 225/225 581/581, 113 lsa comp cam.
05-17-2006, 03:52 PM
#26
05-17-2006, 06:25 PM
#27
Originally Posted by Pro Stock John
I know that car.
I'm going to run my car with the used turbo cam that Kurt from W2W spec'd for someone else, and try it out with my AllPro heads.
I'm going to run my car with the used turbo cam that Kurt from W2W spec'd for someone else, and try it out with my AllPro heads.
