I have not seen anything over 25Hp (crank at $8k ouch) that was not an overbore application. My experience is anything less that 40HP (crank not whp) is not much of jump. Any ideas? thanks

 

Getting 'meaningful' hp gains out of a NA engine is a hopeless task. Short of a stroker, supercharging, turbos, or nitrous, 'big' gains cannot be had. Trust me. I know

 

SW 3,9 conversion!!

 

I love all the Claims of 15, 25hp and 40hp etc on the gt3 from numerous manufacturers of parts.. I will be doing a lot of before and after testing to see what gains can really be had with the 997 Gt3.. Its tough to see anything on a car thats been tuned very well from the factory.. its not a camaro ss.. Its a well thought out and engineered Porsche..

 

No Cats always equals some power! right?

 

Beeive it or not, NOT ALWAYS.. Have seen in MANY cases changing out cat pipe for test pipe MADE NOTHING..

Mike

 

I agree; lots of hyperbole about performance improvements but very little data. Before and after Dyno, or better IMO, Performance Box 60-130 times help to reveal performance gains in a more objective context. Please share anything you can regarding your experiences as you develop the GT3.

I am in the process of acquiring a 2007 GT3 RS. I am very interested in this topic and will be doing some of my own investigating. My current track vehicle was prepared by Switzer Performance Innovation and while Tym's focus is on FI maybe I can convince him to take a look at the GT3/RS platform for a change of pace and consider developing a package for the intake and exhaust aftermarket.

 

Bonehead - thats exactly what I thought. A 20HP increase at the crank cannot realy be felt, I have been there. For this motor the only meaningful increase in HP is the SharkWerks 3.9. However bumping the compression to 13:1 is on the edge. Sounds like they have done their homework however. I have another 11 months on the warranty which gives me time to see how those motors are still fairing. I was interested in exhausts and such but the price/hp is just not worth it, so far.

 

For me it's not just about peak horsepower and torque gains. IMO, you have to consider how throttle response is improved and how the power band (the area under the curve) is shaped. If I can pick up 100-200 rpm on the exit of a corner I know I will be entering the next braking zone faster. Maybe I am making fewer shifts because of this. With normally aspirated engines it's about incremental gains that individually may not be very perceptible. Accumulate these gains over 12-17 corners and your laps times go way down. There is also the practical benefit for a car that is a daily driver. On the street this yields a more driveable, tractable car that is ultimately more fun to drive.

All in all, with normally aspirated engines I think you have to consider the bigger picture and resist the urge to over simplify performance gains into 1 or 2 data points (see my sig below) that, while easy to share, aren't fully representative of the end result.

 

much easier to get big gains on a turbo. check out evolution motorsports in arizona, they have done extensive dyno work with sw's new gt3 (2010) and have a rather affordable ecu tune.

alan

 

thanks Alan I will take a look at them.

mxk116 - thanks for the feedback.
for what its worth and strictly my opinion, where I am coming from is the that 20Hp crank for $2-4K on lap times can be supremely trumped by tires, pads, car balance, tire pressure, bad hair day etc. I would pull the trigger if it was more like 40HP. HughP

 

hey hughp3, good chatting to you today (I think that was you?) and it's _very_ hard to make power on these engines. Software will get you a few but other than building the motor etc... that's all you can really do

 

No question the cost per unit of performance is high especially when compared to the gains available with FI applications. My central theme is consistent with yours though; there are numerous variables that contribute to/result in performance gains. However numerous small incremental gains can be summed and yield fairly substantial improvement. But your point can not be disputed, when it comes down to developing more hp & torque in a NA engine, without more displacement, bolt-ons and/or ECU tunes are not going to yield a big bang for the buck.

 

The EVOMSit software opens up the car a great deal for a NA application. I would also recommend a Sharky or RSS center muffler bypass pipe. We have seen around 25HP and our customers have been extremely happy with the results for the money.


*** Please keep in mind these numbers are on 91 oct.

 

Hey Sharky - Yes thats me. The ultimate would be your 3.9/500HP end all kit. For the time being would there be a lesser alternative untill I have the strength the tell the wife?

Thanks Rennsport1 - with 25WHP increase on a mustang dyno (vs DynoJet) does give about 30HP at crank given 15% drivetrain loss if I have that right. Do the numbers inlcude the exhaust system? What would 93 octane look like? So thats close to my 40HP crank needed given a Mustang Dyno which seems to measure a good bit lower (more true maybe) than other Dyno systems. Does the system require a ProTune or is it a reflash?

Best HughP