i have a 94 formula and people tell me if i cut my cat off it will cause it to over rev does anyone know wat this is and if i should just put a new cat on there or some piping?

 

it revs higher. i gutted my cat, and at wide open it will bounce off the rev limmiter. i just used my hypertech programmer to adjust the rev limmit up a little and no problems anymore...

 

Why not just use your right foot to control the revs? Any engine will hit the rev limiter if you continue to hold the throttle wide open.

The small loss of back pressure, and resulting small increase in HP should not cause the engine to "ovvering" (over rev?). Nothiong you can't control with correct application of the throttle. Resetting the rev limiter doesn't make much sense.

 

Injuneer, you have a good point. But im hoping hes talking about when hes driving the car and holding it to the floor (wot).

Yes, if you remove the cat on a auto it could make it hit the (rev limiter) easyer. Not a big deal. I've had two customers cars do this and one other that didnt phase it... Yes you can let off the gas a little and make it shift, but who wants to let off the gas when your trying to go fast or running at the track...
I would say do it. More than likely it shouldnt change anything. The two i had would say was more of a freek thing, and one of the customers cars I had had prior tuning (by some one else) so I dont trust it...

 

If its an auto, you reprogram the shifts.

 

or just turn the rev limmit to 6400 from 6200

 

If you want a stock-engined car to run slower, sure.

 

run slower?

 

Why would you want your stock engine to turn 6,200 rpm?

 

a stock lt1 dosent make power much past 5900-6000 rpm. best bet would be to change shift points. (shift earlyer)

 

They put the limiter at a specific RPM for a reason... adding 200 rpm in it without upgrading parts just seems like Russian roulette.

 

If i remember correctly doesnt the stock rev limiter cut fuel and not spark. On the first lt1 i built i just barely hit the rev limiter, it detonated and blew a hole in a piston and completely destroyed a rod. I dont even run a rev limiter anymore i just have the shift points set...

Oh and i wouldnt think removing the cat would make it overrev on an auto. I removed mine when it was stock and the only thing i noticed was the louder exhaust tone.

 

Yes you are right it dose shut fuel off on the revlimiter... But Im pretty sure that didnt blow a hole in your piston..

 

Not sure but wont cutting fuel cause a lean condition and then detonation? My motor sounded like it detonated right before it blew up. It happen a right when it hit the rev limiter.

 

It's not a lean but combustible condition, it's an out-of-fuel condition. There is no detonation because there is no copmbustion. Lots and lots of people have hit the rev limiter without holing thier pistons. Something else was wrong..

The factory shuts the fuel off instead of the spark to protect the catalytic convertor...raw fuel dumped in a convertor will cause a convertor to dramatically overheat and fail....