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Old 07-17-2020, 11:02 AM   #6
PV Abuser
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Join Date: May 2004
Location: St. Louis

The cam might not help, though. Although it might if it's some magical modern cam lobe shape that doesn't trade off low-end torque for high-end power. But mostly, cams just move the peak power up or down in the RPM range. Moving it higher creates more peak hp[, because (to simplify) HP is torque times RPM. But if the cam wants to make power higher, but the carb can't flow enough air, you 've made a tradeoff with no benefit, traded low-end torque for no high rpm power (because the carb can't flow).

Very generally speaking, the valves on a stock B20 head flow well enough at low RPM's, I don't think you'd gain anything, but then again I've never tried to make a stump-pulling low revving B20 either. One thing that WOULD add torque - doing an overbore and putting B21 pistons. Almost 10% more displacement. If you do that on an otherwise utterly bone stock motor, you won't increase peak HP much (because it won't flow much more air at higher RPM's), but you will fatten up the torque down low. And if you really feel like hitting it with your purse, stroker crank (and special rods and pistons) - a different way to add displacement, combine both and make a 2.3L (or bigger).

I'm not sure what sort of use the TT3 cam is suited for - but again, you're going to want to stick to 'tractor' cams - cams optimized for lower RPM use. The valve timing and overlap and even lift that makes more power at higher RPM's doesn't also make more power at lower RPM's. To get maximum results, everything needs to be sort of built around a certain RPM range.

It's just that usually, that RPM range gets pushed up higher and higher because that's how you make more HP. Which requires lots of changes to support revving it higher, flowing enough air through the whole system, the ca, etc. Making more torque at low RPM's where there are few bottlenecks, to begin with... is trickier.
'63 PV Rat Rod
'93 245 16VT Classic #1141
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