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Originally posted by Swazo:

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I'll have to see if stilov has any of your pics and I'll check it out your tank setup. I did see one with your IC though...

It sounds like you're at where I'd like to be with my SVT. Running 7-9 lbs of boost with no issues.

Keep the torque up as engine rev's up? With SVT cams and FI...that should be fairly easy to do with proper tuning, right? Or do you have something else in mind? I noticed you were talking about a variable boost contoller in another thread....

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Ok, this might be long but its worth it!

We always talk about horsepower but in the end it is the shape of the torque curve that is really important...and of course the amount of torque. As I stated above, mathematically horsepower is a timed summation of all the torque. It is linearly related to RPM which is a factor of time. However torque is not a linear function in itself. You want to make the torque as linear as possible so that the power continues to build all the way to redline. Since most engines make torque only over a narrow rpm range, the torque at higher and lower rpms is usually less than in that optimal range. You want that torque in your optimal range to be matched to your transmission and your redline (powerband). SVT did a great job of this with their cams for NA and the cams still work well for FI. However, they are not the only way to go. I have tested both SVT cams and Escape cams now with approximately the same levels of boost and with the same intake manifolds. The SVT cams produce a flatter torque curve at the expense of the peak torque numbers. The escape cams allow more of a peak and sacrifice more torque above and below the optimal rpm range.

So decide whether you want a flat torque curve with less overall torque or a peaked torque curve with higher peak torque. In the end you want to maximize your torque curve in your operational range so that your horsepower curve NEVER sees a negative rate of change... i.e. never starts to dip back down. Since there is more than one way to skin a cat lets look at the possibility with the SVT cams and with escape cams. lets look at the rpm range of 4500-7000 rpm, the maximum width of your shifting powerband and where you want the most torque and consequently the fastest car.

SVT cams: less peak torque, holds the torque longer as rpm goes up because they "breath better" or have more overlap between intake and exhaust lobes. More overlap means better high rpm breathing. Easy to make good power with moderate boost but harder to pressurize the cylinders because the boost begins to push out the exhaust valve in the intake stroke due to the overlap. If you want bigger power you just raise the boost until the engine blows up or you get the level you want. The torque curve will still be reasonably flat.

Escape cams: Big torque peak around 5000 rpm with a faster drop off than the SVT cams above 6000rpm. Peak torque is higher due to less overlap but peak power happens about 5800-6000 rpm, in effect losing 1000 rpm of opertional range from 6000-7000.

If you use a boost controller like the GReddy E01, you can program boost per rpm. You can flatten the torque curve by having a linear increase in boost or by a more rapid increase in boost. The easy way to make these cams perform better than the SVT cams is use low boost and let the excellent low-rpm breathing of the cams fill cylinders easily, making good power and then as power starts to drop around 6000 rpm you just add incremental amounts of boost to keep the torque curve linear.

To get the same peak torque with SVT cams you have to raise the boost even higher than the escape cams over the whole range and not just at the end.

Things that will help the escape cams work well would be headers rather than simple stock manifolds like I am using right now and of course a nice big 3" exaust. Secondary butterflies in the intake manifold are not necessary at all with escape cams and definitely not with a turbo though they make driveability in non-boost situations with SVT cams better.

With a good intake and exhaust along with a programmable boost controller and you can hold the torque level to a safe 325 ft-lbs all the way to redline.

325*7000/5252= 433HP

You can even keep the boost low in certain gears so that you can prevent wheelspin.

With SVT cams you can still use the programmable controller to keep the torque at the desired level and achieve the same results but your boost will be higher because the cams have more overlap. Still neither will be a problem as long as the turbo is boosting in an efficient range.
I don't see enough of an advantage from one cam system over another for me to go and change them out at this time, especially sinc the turbo is the great equalizer. I would use what was available and not go seeking out SVT cams unless I already had them.