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**JohnStranahan** · 07-03-2008, 11:49 PM

OrionLion182
OK-This is what I notice. Cornering is my game and some top speed runs. At about 2200 to 2500 the motor pulls well, just a little weak, bone stock in the corners. Then you add a cold air intake (Cosworth or Focus Sport I have had both), larger MAF housing then an egine program to tinker with it. Now you have a bit of a stumble on occasion on very hard cornering at the RPM's mentioned. Your full power runs are improved. You tune most of this stumble out with the engine program but you have to go about 6% rich overall. That is my only handle at the moment to correct the stumble. It is still there just better. I suspect that air velocity is lost midrange. You have very good air velocity at the throttle body, but then its dumped into a huge tortuous path manifold. By the time it reaches the last runner any hint of velocity is lost.

Aftermarket engine programs seem to be suited to full power runs on the dyno but fail in the corners. SCT.

What a multiple throttle body does is keeps that high speed jet of air directed right at the valve train on part throttle. A larger overal area for four of these little throttle bodies may improve top end. I can go 130 mph at present. Cornering is at 1.0 g's. Trying to extract the max with minimum expense. Throttle response is super with individual throttle bodies (ITB's). I want to eliminate the stumble and improve part throttle performance.

Not trying to turn my Mazda engine Into a Honda. Just adding small Suzuki throttle bodies to my Ford.

I will note that a record holding ultimate Solo (autocross) car driver has a Duratec with ITB's in his newest ride. There was a writeup in a recent issue of "Sports Car".
john

07-03-2008, 11:49 PM	#145
JohnStranahan Junior Member Join Date: Dec 2004 Posts: 98	Re: Suzuki GSXR 750 quad Throttle Body Install on 2.3 L Duratec OrionLion182 OK-This is what I notice. Cornering is my game and some top speed runs. At about 2200 to 2500 the motor pulls well, just a little weak, bone stock in the corners. Then you add a cold air intake (Cosworth or Focus Sport I have had both), larger MAF housing then an egine program to tinker with it. Now you have a bit of a stumble on occasion on very hard cornering at the RPM's mentioned. Your full power runs are improved. You tune most of this stumble out with the engine program but you have to go about 6% rich overall. That is my only handle at the moment to correct the stumble. It is still there just better. I suspect that air velocity is lost midrange. You have very good air velocity at the throttle body, but then its dumped into a huge tortuous path manifold. By the time it reaches the last runner any hint of velocity is lost. Aftermarket engine programs seem to be suited to full power runs on the dyno but fail in the corners. SCT. What a multiple throttle body does is keeps that high speed jet of air directed right at the valve train on part throttle. A larger overal area for four of these little throttle bodies may improve top end. I can go 130 mph at present. Cornering is at 1.0 g's. Trying to extract the max with minimum expense. Throttle response is super with individual throttle bodies (ITB's). I want to eliminate the stumble and improve part throttle performance. Not trying to turn my Mazda engine Into a Honda. Just adding small Suzuki throttle bodies to my Ford. I will note that a record holding ultimate Solo (autocross) car driver has a Duratec with ITB's in his newest ride. There was a writeup in a recent issue of "Sports Car". john