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Well I took my car back to UpRev to retune after I pulled the intake standoff out of the motor. The car put down 294 rwhp. Much better but that is about all this motor is going to put down with my intake manifold. You can see the power the climbs strong to 6200 rpm then suddenly nose dives. Looks like its just not getting enough air flow. Hopefully the Cosworth manifold will solve this problem.
Ever think of adding a larger TB and a TD 2.5" exhaust? Comapred to the Nismo your power up top wont drop off as much.
Yes...I plan on going back to UpRev to try I believe was an 80mm TB that they have there at there shop. I want to go to a local dyno and get and experiment to see if I can make more power by opening up the exhaust before I by another one. I am sure the Nismo exhaust is hurting the performance with this motor, especially on the top end.
You can see the car make at least stock power or higher from 3000 rpm up. We learned that the VTC angles are very important with these Tomei cams otherwise the power wouldn't come on until 5500 rpm. Had I bought the Nismo pulleys I am sure I would have made alot more power from 1500 rpm to 5500 rpm. The cam advance should have been around 50 degrees between that range. Just moving the advance around 5 degrees to the maximum of 40 allowed me to make between 10 and 20 rwhp in that range.
Try to redyno without an exhaust on just to see what kind of power you make. I wonder if the nismo is restricting anything. I agree that the intake manifold is the cause. Would porting and polishing the stock intake manifold help? My intake manifold is very rough on the inside. Getting it smoothed out would really reduce the friction in there.
I would have to think the Nismo exhaust is part of what is restricting this motor. I am running the stock air box but air flow into this motor is extremely loud compared to stock internal motor. You can actually hear the air getting drawn into the motor. I would have to believe the air is flowing in alot faster than what the Nismo exhaust is allowing the motor to expel. Even though I don't believe I will make giant gains by removing any exhaust restriction it may be enough to hit the 300 mark.
Try to redyno without an exhaust on just to see what kind of power you make. I wonder if the nismo is restricting anything. I agree that the intake manifold is the cause. Would porting and polishing the stock intake manifold help? My intake manifold is very rough on the inside. Getting it smoothed out would really reduce the friction in there.
Definitely making progress which is good!
The NISMO exhaust is not even close to being a restriction - don't anyone let you believe otherwise.
There are a few reasons the power is what it is - the headers are the primary restriction right now, not the throttle body - stock throttle body is very large and you're not close to maxing out the amount of air it can flow through it yet. Those are just the wrong headers to use with those cams. That is a primary reason why despite you having alot more cam than me, and bigger valves (I'm on stock heads/stock valves), your power falls off so early in the rev range vs mine. The Cosworth manifold might help...but it's not going to let that motor do what it's supposed to though till you ditch those headers and go with something alot more aggressive (Crawford, at least, though preferably, something custom). That's also another reason why your torque curve looks so disjointed (though there is more to it, it's a big contributing factor)
Z1 do you think the crawford hearders are worth the investment in terms of picking up significant gains over the Nismo? I would like to try them just don't want to buy them and only gain just a few more horse.
Adam-I am not arguing with you-just respectfully disagree
While the Nismo exhaust may not be resticting much of this set-up @PEAK, I do believe it is a restriction. Ive seen Revup motors with bolt-ons with IDENTICAL set-ups other than the Nismo exhaust (also seen it with y-pipe single 3", and in this case an Injen 2" TD exhaust dyno back to back. The PEAK power was identical to each other, but the TQ curves and hp curve up top were vastly different. Y-pipe car made more midrange, but TQ fell of harder up top. Injen car made less power under 4000rpm's but didnt drop as much TQ after 5500rpm's, made for a much better TQ curve. The TD exhaust equipped car pulled at the top of 4th on the "track" and crept away through 5th gear. If I was doing an NA build Id do a TD exhaust based off of seeing those differences alone, but what do I know...
New dyno numbers: 294 rwhp
Very impressive
. Its nice to see more NA Z33's being built.
