View Single Post
911st 911st is offline
Registered User
Join Date: Jan 2004
Location: Sacramento
Posts: 7,269
The 993TT's can manage boost at the injection controller. Thus, they can run larger boost earlier for a flatter boost curve. On top of that the water cooled TT's also have variable cam timing that moves the efficiency island of the cam around for a flatter TQ curve.

A 930 cam is going to make its best power early, SC early to mid, C2 Mid, and a race cam mid to later in the rpm range.

Just playing with one's cam timing can move things around some. The SC makes power about 250rpm higher, and the C2 about 250rpm higher again. If one wanted to they could move the peak HP point to about 6100rpm with C2 cams. Making peak power at 5250 v 6100rpm can result in a 16% higher peak HP but at the expense of low end to some degree.

If one gets HP peak to be past 5220rpm a bit, then HP can start to be a higher value than TQ.

On a well built motor, different cams do not typically make more peak TQ. By moving the TQ range to a higher RPM, one makes more HP.

350 # of Torque at 5000, 5225, 5500 and 6500 rpm is 335, 350, and 368, 436hp.

One of the issues in doing this with a CIS motor is it exaggerates the need for fuel and larger components like ports & turbo sizes.

Sorry for the ramblings.

ps, power at 3000rpm on a turbo is more a function of turbo sizing and how fast boost builds.

Last edited by 911st; 04-10-2010 at 11:13 AM..
Old 04-10-2010, 08:57 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #78 (permalink)