I have a 91rs with a 305 tbi. Been considering changing it to a carb, for better tuneability. I'm sure others have done this, can anybody tell me if it made a noticeabe difference on output, or was it worthwile?

 

Once upon a time, my family had an '86 Camero that we carbed. Expect to spend a lot of time under the hood (especially if you are a newbie at this) jetting and tuning. My dad, who is a motorhead from way back, had the worst time with that damn car. Getting it to run in cold weather was no fun either, but if you've got the wrench time and that's really what you want, then do it to it!

 

If the main reson is tuneability you should stay with the TBI. With the right equipment you can do much more with a TBI than with a carb.
Do you have the 8746 ECM?
If you have access to an old laptop ( late 486 or early pentium will do ) you are almost there ...
Then you need a prom burner and some eproms.

With the WinALDL scanner software ( free ) http://winaldl.webhop.net
WinBin prom edit software ( free ) http://www.spiritone.com/~eoa/Cars/EFI
you can scan the car and modify the calibration.


You could probably get more power with a differnt intake and a bigger carb, but that is not from tuneability, that is just better breathing. The gas mileage will be worse with a carb than with a well tuned TBI.

 

ithought about it for awhile then decided against it...would cost around at least 700$ plus a major pain in the ***...just get a new manifold, with an adapter and a holley 670cfm TBI if you want better breathing and more fuel...it would be much easier to install..wont have to change distributers or anything