GT2871 USERS. SR motor - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

steve shadows · 08-19-2008, 06:55 PM

You MUST match cam duration/or power band effectiveness to the compressor you are using.

If you are say using a T67/T3 that spools up full boost at 5300 rpms then 264 cams are a terrible camshaft to be using. You should be using at least 272 cam durations with a relatively aggressive lift.

If you are using a .86 2871R for example. I would suggest a duration of 264-266

For 2871R .64 I would say a 260 Tomei cam would do the trick just right.

Matching cams to the turbo can make or break how aggressive the on power is.

You cannot fight the turbo. The turbo will want to make power about 1000 rpms after you get full spool on your turbo on sr20s (and a lot of other smaller 4 cylinder engines with similar heads).

I would suggest going with the flow.

If you have a GT30R for example lots of lift and moderate duration

If you have a 2871R for example moderate lift and moderate duration

If you have a GT35R for example aggressive lift and aggressive duration

If you have a GT4088R for example aggressive lift and very aggressive dur.

and so on and so on.

This is all proven over the last 1-2 years of using the dyno dynamics I have with various different sr20det setups and cam combinations.

08-19-2008, 06:55 PM	#11
steve shadows Post Whore! Join Date: Aug 2003 Location: LA and OC Posts: 8,202 Trader Rating: (5) Feedback Score: 5 reviews	You MUST match cam duration/or power band effectiveness to the compressor you are using. If you are say using a T67/T3 that spools up full boost at 5300 rpms then 264 cams are a terrible camshaft to be using. You should be using at least 272 cam durations with a relatively aggressive lift. If you are using a .86 2871R for example. I would suggest a duration of 264-266 For 2871R .64 I would say a 260 Tomei cam would do the trick just right. Matching cams to the turbo can make or break how aggressive the on power is. You cannot fight the turbo. The turbo will want to make power about 1000 rpms after you get full spool on your turbo on sr20s (and a lot of other smaller 4 cylinder engines with similar heads). I would suggest going with the flow. If you have a GT30R for example lots of lift and moderate duration If you have a 2871R for example moderate lift and moderate duration If you have a GT35R for example aggressive lift and aggressive duration If you have a GT4088R for example aggressive lift and very aggressive dur. and so on and so on. This is all proven over the last 1-2 years of using the dyno dynamics I have with various different sr20det setups and cam combinations. __________________ Like Me on FaceBook !