I have used Webcam to build two different engines for F4i's. One is a drag racer and one is a roadracer. I sent my cam cores to Webcam talked to them on the phone describing what other mods I was making and the result was outstanding. The drag engine puts out high torque and the RR engine puts out high HP. The drag guy is running mid fives 1/8 mile and he is still learning the drag game. Webcam is the bomb.

 

If you are after low end power then using a high reving engine is not gonna help, and the RR revs higher,

just my 2p

 

basically we use the high revving engine, but in low gears it would be unheard of to get about 3rd gear in a competition. So we need the low end power and torque, but we are usually revving the pants of the engine because of the restrictor we have to have

 

hmm i might have to make a trip to lubbock to visit id like to come check the bike out

 

From what it sounds like, you are racing mini sprints. I race them as well. If you ArE looking for hp and you ArE running restricted class, here is a good tip to try. I'm assuming that since you are running restricted you are on carbs.

1. Find an RR 03-06 harness and ecu. Send it off and have it cut down for carbs. Have ECU flashed for carbs. Plug it on to your f4i. You will get better ignition advance, higher rpm limit among other things. Also when running restricted class you do not have to run HUGE CARBS such as R6 and XXx CARBS. The F4 CARBS will work great with right tuning and airbox. You can only get so much air and fuel into the engine being restricted. Really won't matter what you do to intake. Its going through a 3/4 hole. Get CARBS right and the RR harness and you will be fine