hey i just got a 91 firebird with a 305 tbi in it, looking for any and all free mods for this engine to make it a little quicker, its my daily driver so i cant afford much on it as im trying to build up the camaro. lemme know guys thanks

 

the easiest and cheapest mod is the open element filter.

the best free mod is advancing the timing by 6-8*

Kyle

 

RebelRacer is right. There's only two "free" mods that I can think of. Advance the timing anywhere from *2 to *8 (keep advancing the timing until you find a good balance of power and gas mileage). The other free mod is the ultimate TBI mods, listed in the Tech Articles: https://www.thirdgen.org/newdesign/t...matetbi2.shtml

The cheapest mod ($30 or less) is a 14" by 3" open element air cleaner. You can get them at any auto parts store. Another cheap mod is the TBI injector spacer ($20), from a place like Jegs. Just check out the "New to TBI" sticky for all the info you could ever want to know about TBI.

 

thanks guys, ive read over some of it....im not going to do much to this car as im building up the v6 i have for now

if i advance the timing do i have to switch octane gas?

 

With todays gas, most likely. 4* advance will typically require 89 octane. I ran 4* on 87 for a long time.

 

help me out here guys... I have been advised that the problem with open elements is that although you get a whole load more air which is good :lala: the air you get is warm/hot which is bad so I guess it's a trade off between lots of crappy warm air or not very much cold air... any comments?

another question relation to TBI is is it possible/advisable to use the tpi intake system to feed air to the TBI?

 

to answer your hot air/open element question - yes you do get more hot air. its a tradeoff for the bottleneck straw tube they have on there from the factory. If you have a few bucks (and a ramair hood by change) go to ram air box website and youll see they have a cover that goes over open elements which force all the air down one big 3" tube. just get some pvc piping and route it into the bumper or wherever you can get some cold air.

the tpi intake used for air...do you mean the air filter and piping or the actual intake itself. You would be doing a swap to mpfi if you swapped intakes, the tpi has no spot for a tb on top. A cool setup would be getting one of holleys or edels intakes (or of course make your own) with a mpfi but the top accepts a regular tb. youd have 8 injectors but use a TBI style of air injection. That would look good since open elements are flashy compared to goofy ram air boxes and such that crowd up TPI engine bays.

 

sorry I didn't phrase my question properly what I should have asked was the possibility of using the tpi air intake to marry-up with the tbi air intake in effect I guess getting a ramair style induction from all that lovely cold air round the front foglight area

 

It's definetely possible, and it's been done before. There are some old threads about it, but I couldn't tell you the names. I know S!MON has done it. Let me see if I can't get some pictures.

EDIT: Here's thread about it, the pictures don't work, but there's a link to another thread about it: https://www.thirdgen.org/techbb2/sho...hreadid=242054

 

bingo!!! well done thank you :lala: you sir are a star :hail:

 

oops double post

 

thats exactly what the ram air box is.... a ram air for TBI cars. except it costs about $100.