IT7 Car Feels Slow...
 

My IT7 car feels slow, obviously it's not suppose to be a rocket but I feel as though I'm down on some HP.

It's all stock minus a header/exhaust, some fancy looking plug wires, and that's about it!

At Road Atlanta it will hit 103-105ish down the back straight before the braking zone into 10.

The car revs smooth and seems to run fine, just lacks some grunt, then again it is a 12A.

Is there anything I can do to gain a few horses in straight line grunt?

The power is found in the exhaust system on an IT prep RX7. There is a little gain from timing advance 26-28 BTDC IIRC is where you want to be. There are some gains in the midrange with carb tuning but it is more about controling HOW the air gets into the carb. Helmholtz resonance comes into play in a proper intake before the carb and you can smooth out the AFR's.

An ITA RX7 should be able to put about 128 to the wheels

Mine always regains some pep after running some Seafoam through the tank...

Other than that, I would look into getting stronger spark on the ignition. I saw unbelievable gains back when I was experimenting with the Transistor Trick ignition system. The only downfall was reliability. :(



.

I'll look into getting more/cool air for sure, I just have the stock intake right now, in fact I don't even have any of the ducting leading to it.

From what another IT7 racer told me based on his speed, I'm about 15mph slower than him down the back straight at Road Atlanta.

Compression check lately? They will run fine with low compression, just not make power.

15mph is a lot.

I plan on doing a compression check this week.

I was thinking carb, because the previous owner did a lot of work with a fuel delivery issue and adjusted the carb quite a bit trying to make it run right so I wasn't sure if it was out of whack and needed a tune or something.

I'd assume I need more than just that though to make up a 15mph difference, that's also one of the fastest IT7 cars in my area though so...

The Racingbeat air filter kit gained 3hp on the dyno on three different cars. That may be a good start.

Yeah I'll be looking into a filter kit/some fresh air ducting and I just found my sound reading from the last race, quite low, I'm thinking maybe the muffler on the car is costing me some power? I'm not even sure of the brand/setup, I know it's only clamped on so it can be removed.

Ah I need next season to start to do a test day and try some things out! :P

I have the air cleaner housing you need. Hit me up.

That other car may be one of the fastest, but if you are getting out of 7 correctly, he should not have 15mph on you. I never had a speedo in my car, nor have I competed with 10A and 10B, so cant be much help on the target mph.

What about your gearing, still a 3:9? The fastest cars in the SE are not running 3:9.