Crazy Plenum Update - More Sillyness Finding Power
Looks like cams 
Many people have said this in the past. Cams have been long blamed for the drop in power after 6500rpm.
Looks like the factory 70mm is just sufficient for stock cams... Really only need more with a more aggressive cam.
Is the roadster a revup?
I wonder what type of signal the ECU would need to see in order to not throw a code. Did the GM TB operate normally otherwise?
edit:
Looking more closely at the header vs header/TB dyno plot, the top end seems to level out and not nosedive down with the improved intake. Not the drastic gains that NISMO cams saw, but this is definitely not discouraging news.
Many people have said this in the past. Cams have been long blamed for the drop in power after 6500rpm.Looks like the factory 70mm is just sufficient for stock cams... Really only need more with a more aggressive cam.
Is the roadster a revup?
I wonder what type of signal the ECU would need to see in order to not throw a code. Did the GM TB operate normally otherwise?
edit:
Looking more closely at the header vs header/TB dyno plot, the top end seems to level out and not nosedive down with the improved intake. Not the drastic gains that NISMO cams saw, but this is definitely not discouraging news.
Last edited by INTIMAZY; Mar 4, 2010 at 03:18 PM.
This doesn't show anything about a 90mm throttle body being beneficial or not from what I can see...the test of that would have to be a back to back on the cammed car IMHO (or this car, new plenum + stock throttle body if its possible). That might skew the results though as the plenum is designed around that 90mm throttle body. This setup as a whole is going to reward cams and rpm...like any proper intake manifold should. The setup that maximizes the stock cams are the one the car comes with already coupled with the spacer to alleviate the air distribution inequalities (+ a non revup collector if being used on a revup engine).
What I'd really like to see is how this plenum design does with a better set of cams. That is what those headers are begging for IMHO
Keep it up...fun stuff! I'll be up your way in a couple weeks, if I've got any spare time, would love to swing by
What I'd really like to see is how this plenum design does with a better set of cams. That is what those headers are begging for IMHO
Keep it up...fun stuff! I'll be up your way in a couple weeks, if I've got any spare time, would love to swing by
Last edited by Z1 Performance; Mar 4, 2010 at 03:25 PM.
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From: Brampton, ON
It really looks to me like the factory intake and revup cams seem to be well paired in that they both become restrictive around the same power level. But that can't be confirmed until I install larger cams and then re-test the intake.
However, since that is essentially the test that we did on the race car, I am pretty certain it will hold true on the roadster as well.
It's extremely interesting to see how things interact on an N/A motor, right when you think you have something figured out, something throws you a curveball!
I would imagine the HR has a "fatter" cam, or more area under the lift curve if you will, that helps it keep airflow up at higher RPM. If it's not that, then it could perhaps be better valve seat and valve angles that improve flow at low lift.
Regardless, I'm disapointed that it doesn't look like either the revup or non revup will be able to achieve 300whp without installing larger cams.
We're still doing a lot of testing and hopefully soon we will have a 300whp bolt-on package for the community.
However, since that is essentially the test that we did on the race car, I am pretty certain it will hold true on the roadster as well.
It's extremely interesting to see how things interact on an N/A motor, right when you think you have something figured out, something throws you a curveball!
I would imagine the HR has a "fatter" cam, or more area under the lift curve if you will, that helps it keep airflow up at higher RPM. If it's not that, then it could perhaps be better valve seat and valve angles that improve flow at low lift.
Regardless, I'm disapointed that it doesn't look like either the revup or non revup will be able to achieve 300whp without installing larger cams.
We're still doing a lot of testing and hopefully soon we will have a 300whp bolt-on package for the community.
It really looks to me like the factory intake and revup cams seem to be well paired in that they both become restrictive around the same power level. But that can't be confirmed until I install larger cams and then re-test the intake.
However, since that is essentially the test that we did on the race car, I am pretty certain it will hold true on the roadster as well.
It's extremely interesting to see how things interact on an N/A motor, right when you think you have something figured out, something throws you a curveball!
I would imagine the HR has a "fatter" cam, or more area under the lift curve if you will, that helps it keep airflow up at higher RPM. If it's not that, then it could perhaps be better valve seat and valve angles that improve flow at low lift.
Regardless, I'm disapointed that it doesn't look like either the revup or non revup will be able to achieve 300whp without installing larger cams.
We're still doing a lot of testing and hopefully soon we will have a 300whp bolt-on package for the community.
However, since that is essentially the test that we did on the race car, I am pretty certain it will hold true on the roadster as well.
It's extremely interesting to see how things interact on an N/A motor, right when you think you have something figured out, something throws you a curveball!
I would imagine the HR has a "fatter" cam, or more area under the lift curve if you will, that helps it keep airflow up at higher RPM. If it's not that, then it could perhaps be better valve seat and valve angles that improve flow at low lift.
Regardless, I'm disapointed that it doesn't look like either the revup or non revup will be able to achieve 300whp without installing larger cams.
We're still doing a lot of testing and hopefully soon we will have a 300whp bolt-on package for the community.
I'd settle for 280whp package....lol.
Seriously though thanks to guys like you and hydrazine for working hard to find extra power and be innovative.
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Joined: May 2004
Posts: 183
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From: Largo, MD
...lmao
It really looks to me like the factory intake and revup cams seem to be well paired in that they both become restrictive around the same power level. But that can't be confirmed until I install larger cams and then re-test the intake.
However, since that is essentially the test that we did on the race car, I am pretty certain it will hold true on the roadster as well.
It's extremely interesting to see how things interact on an N/A motor, right when you think you have something figured out, something throws you a curveball!
I would imagine the HR has a "fatter" cam, or more area under the lift curve if you will, that helps it keep airflow up at higher RPM. If it's not that, then it could perhaps be better valve seat and valve angles that improve flow at low lift.
Regardless, I'm disapointed that it doesn't look like either the revup or non revup will be able to achieve 300whp without installing larger cams.
We're still doing a lot of testing and hopefully soon we will have a 300whp bolt-on package for the community.
However, since that is essentially the test that we did on the race car, I am pretty certain it will hold true on the roadster as well.
It's extremely interesting to see how things interact on an N/A motor, right when you think you have something figured out, something throws you a curveball!
I would imagine the HR has a "fatter" cam, or more area under the lift curve if you will, that helps it keep airflow up at higher RPM. If it's not that, then it could perhaps be better valve seat and valve angles that improve flow at low lift.
Regardless, I'm disapointed that it doesn't look like either the revup or non revup will be able to achieve 300whp without installing larger cams.
We're still doing a lot of testing and hopefully soon we will have a 300whp bolt-on package for the community.
Any Updates?
Im pretty sure the DE community is just itching for innovation and new hp mods if they are available and within reason for dollar/hp.
I know I am after a tune.
These gains are very impressive! Maybe I missed the point to this thread though. SGSash, are you guys simply pointing out that our plenum is inefficient? Or is there any plans to try and put a more practical version of this plenum used into production?
I believe they're looking to produce something...check out their website:
http://www.sg-motorsport.com/development.html
http://www.sg-motorsport.com/development.html
