I'm wondering what kind of power gains I can get by converting my 305 TPI to carburation? Is there anything that I should be carefull about (holes to plug, all the sensors to take out, etc.) I did a cam swap to a 212 dur // .473 lift with headers and dual exhaust and now it runs like s**t because of the computer. I am trying to learn as much as I can before I dwell into the realm of conversion. Thank you.

 

A .212 duration cam won't make your ECM go nuts. That's too low of a duration. I'd look elsewhere for the reason the car doesn't run very good. Carburation will net you at least 40-50 HP in my opinion.

 

40-50 HP just by putting on a carb? Wow, sounds like alot. I think that my problem might be the TPS or an air leak. It's still alot to think about, converting my engine to a carb setup. My instinct tells me to stay with the TPI setup. What does everybody think?

 

With a 305 I'd stick with the stock intake. Just buy a dremel and some bits and port everything decently. I had a 204/214 duration cam in my 86, no ill effects at all.

 

Stick with what you've got. If you want to upgrade your intake, rather than spending the 400 bucks on a carb, spend it on a stealthram or lt1 modified intake. You can use all your existing sensors and ecu that way as well... first i'd see what's causing your car to run poorly.

 

40-50 Hp. over a tuned port, come on. If that was true they would be selling so many carbs you would be on a waiting list. The only reason to switch to a carb would be if one wanted no electronic management of the engine. A properly set up fuel injection system has far more benefits than a carbed engine. For a complete set of facts about carbs vs. TPI see http://www.geocities.com/F_body28to3...toryof_fi.html

 

Any car takes tuning to get it to run it's best.
For a TPI car that means learning how to do chips. yes, it's about $200 to get the bits, and some learning, but a good distributor, and selection of jets ain't much cheaper.

If you don't want to learn how to do chips, and be able to tune your motor, then a carb long term would be the answer. But, if you move, or the laws change around you, you'll have to reinstall the TPI anyway.

 

Well, i think i may have to agree that a carb setup will gain 40-50HP. This would be with a power peak of over 5500 RPM and you will greatly lose torque down low and change the whole power curve of the engine.

IMO i'd get it to someone that knows how to diagnose and tune a TPI. Leave it on there.... Especially if this is going to be a street car or daily driver.

 

I speak from experience. My car WAS tuned port for most of its life. I gained A LOT of power after I switched to carb. So much more that I didn't need the NOS system I had on the TPI for a while. Now I'm going back to fuel injection, but I'm getting an LT1 intake.

 

The carb setups make more HP, the TPI setups make more torque.

You need to fix your engine before you attempt any performance modifications.. There are soo many reasons it could be running poorly it aint even funny..

And as much as I think burning a chip is a good benefit, don't let anyone tell you your "stock chip" is your problem.. I'm still running a stock chip, because I'm still in the tinkering phase of things. Last thing you want is to be troubleshooting mechanical AND management problems.

-- Joe

 

Well thanks guys, I appreciate the input. I've made my decision, I'm sticking with TPI. I"ll just find out what the prob is and fix it, then drive it, then smile for a week .....Have a good day.

P.S. I'll keep you guys posted on what the problem was. There is no better lesson than someone elses mistake!

 

I found out that the problem was the Vehicle Speed Sensor (VSS.) When I drove to the muffler shop with open headers, it melted the speedo cable. I put my car on a diagnostic computer at GM. They said it was the VSS (speedo cable.) The VSS is directly related to the TCC (Torque Clutch Convertor)and it tells the TCC when to engage by telling it how fast the car is going, that's why it ran like ****. It's like I only had 10 hp from 1000-3000 rpm. Now the thing goes like a bat outta hell! Keep those camaros running hard, thanks for the input.

 

i would stick with tpi every camaro i have ever ran that had a carb on it i have killed unless there really pushing some power. if carb was better then the tune port whhy would gm ever have put them on are cars??

 

emissions and mileage