[rhibbsiii]

I have a 85 firebird. I wanted to konw if I put a lobe cam in will the computer become confuesed. Do I have to get a special chip or will it be fine. There was an engine swap done before I bought it. Swapped 305 for 350.

[sbchevfreak]

???? A what????

I think you mean a higher lift cam. Up to a point, you can swap in hotter cams, but if you go past what is advertised as "computer safe", you will need to reprogram your ECM(chip).

[rhibbsiii]

Sorry bout that I want a rough idle

[Hippie]

Originally Posted by rhibbsiii

Sorry bout that I want a rough idle

Rough idling cams and TPI don't play well together.

[sbchevfreak]

Any cam that will give you a choppy idle is going to require extensive reprograming to get the engine to run right. Just a cam swap won't do it either. You need to build the whole combination. You might get a choppier idle, but the engine will be an absolute dog. The stock heads won't flow properly for the more aggressive cam, and the engine will be a gutless gas hog.

[sbchevfreak]

Originally Posted by Hippie

Rough idling cams and TPI don't play well together.

Yup. If you want the choppy idle, you'd be better off going to an aftermarket high performance injection system, and then building a complete engine, matching all the capabilites of the parts. You will be much happier with it. It can get pricey, but horsepower costs money.

[rhibbsiii]

I think I would much rather have a bigger cam and keep the same intake I also want to add domed pistons I havent torn the engine apart yet

[PatM]

The other replies (above) are all sound. But it sounds like you know what you want to do, and really might not be too interested in any other thoughts. If that's the case, perhaps you should experiment. After all, it is in fact your money to play around with. After all, we all learn by doing, and part of that is trying things others say won't work, won't fit, or won't be too successful. Usually, we find our wise friends are right. But it's rightous when we can prove them wrong.

Just for the record -- Lumpy cams and factory EFI usually don't mix. Course, that's just my opinion. But using and old style Holley Projection unit without closed loop feedback might work just fine. Perhaps someone here has tried a big lift, long duration cam with one and could comment.

Good Luck -- let us know how things come out.

Pat