1986 firebird 2.8 v6 auto 189000 miles
when I start it up and drive without warming it up it feels like it has more power, once its gets warm it looses power why would this be? do I need new motor?
also how much hp over stock will this give me
Melling M-Select Class 1 Camshafts: MEL-MTC-5 - summitracing.com

thanks
Will

 

It's running in open loop at startup, so it's getting more fuel I think.

I wouldn't do that cam, perhaps look at a compxe line up one. Your engine is MAF right? (if so a new cam would actually work, without extensive computer tuning).

Try a new fuel filter first, that's my first shotgun effect cure all.

If that doesn't help, try posting in the V-6 forum, those guys know the V-6 motors best (and could help better with a cam selection.)

 

you don't need a new motor. your oxygen sensor is most likely inoperative. this sensor isn't read by the computer until your car is warm. if you've noticed decreased mileage recently, this is definitely your problem, and only a $20 fix. the sensor is located in your exhaust pipe--it looks like a spark plug. you'll need an open-ended wrench (I believe 7/8", but double check), or an oxygen sensor socket to replace.

 

Your engine is in what's called "open loop" mode when you first start the car. It doesn't take readings from the Oxygen sensor until it reaches nomal operating temperature. Combine that with an intake that's ambient temperatue, allowing a colder, and therefore more dense air charge as well, and the car has much more performance than after it's completely warm.

As for that cam, check the V6 forum

 

Thanks guys I will change the oxygen sensor and see what that does I just got the car a week ago gas mileage sucks lucky if I get 200 miles out of a full tank
thanks
Will

 

Better not to romp on it when its cold anyway.