350 TBI

[nj85z28]

hi im looking to get more out of my 305 TBI 89 RS, and i have a 350 TBI unit, just wondering if switching the units would help put some more snot under the hood, or if the switch would even be worth the trouble

[90FormulaWS6]

the bores on the TB are the same for the 305 and 350 but the injectors flow better... stock 305 injectors are inadequate for stock applications so it would be useful to put the injectors in there

[NJSPEEDER]

for stock system the injectors won't really help you much. teh stockj tuning actually runs the car a little bit rich. you can however modify the extra tb to flow better and then swap it on to get a little "free" hp gain.
best freebie you can do is to bump up the base timing about 4 degrees. it dramatically increase throttle response and power.

hit me up on AIM and i cna explain more free/cheap mods to get yoru car moving.

later
tim

[deadtrend1]

also, flip the air cleaner lid upside down.

[Blackwizard222]

lol air cleaner lid trick, just dont rain get in it. U can get a throttle body spacer for it and holley make a tbi unit but i heard they arent that great. The bores on the 305 and 350 tb are the same as mentioned before so u will just get more fuel from a higher impedence injector. I had an 89 rs with a 350 tbi, i always pondered swapping it out for a carb and intake but i ended up selling it before i did anything with it. since the tbi is basically a truck motor its kind of a dead end situation, convert to carb or got tpi and ull have more options.

[Batman]

Don't go with the Holley for a 305, it is WAY too big for a 305.

[Koll]

Originally Posted by NJSPEEDER

for stock system the injectors won't really help you much. teh stockj tuning actually runs the car a little bit rich. you can however modify the extra tb to flow better and then swap it on to get a little "free" hp gain.
best freebie you can do is to bump up the base timing about 4 degrees. it dramatically increase throttle response and power.

hit me up on AIM and i cna explain more free/cheap mods to get yoru car moving.

later
tim

explain the timing bump

[NJSPEEDER]

base timing is where the distributer is set from the factory not including the timing that the computer adds in automatically. on stock tbi it is set to 0degrees. if you move that base number to 4degrees before top dead center it increases throttle response and power across the whole rev range.
it jsut gives teh flame front a little head start on expanding so it pushes harder on the piston.

later
tim

[89 Trans Am WS6]

I agree with tim. Give the a 4 or so degree advance is definitly a good thing with the L03. However make sure your adjusting BASE timing. You have to unplug a connector to set base timing, or else your adjustment will be out of whack. If you look on the emissions sticker under the hood it should tell you what wire to disconnect.

I would definitly do the "ultimate TBI" mods to that throttle body. A quick search on TGO will tell you how to do that. Basicly uncorks the TBI a bit. When i had my 89 TA i had a 14x3 open element air cleaner with a KN. The open element alone gave more SOTP difference then any other mod i did i think.

If your going to keep that motor do intake, and exhaust. Then go for some computer tuning. If you can find someone to help you out their, or you learn it yourself there is a great deal of potential in that alone.

Thats what im currently doing for my 93..looking for someone to do some initial computer tuning to bring my ets down before i learn on my own.

joe

[Fasterthanyou]

I've been known to do TBI some justice. Just got back from AZ where I tuned a guys car and showed him how to do it himself. The dyno he had paid charged over $900 and had 41 degees of timing at WOT, hmm... yeah, about the motor damage.
I also do LT1's 93-95 and can show you how to do your own.

[nj85z28]

yea def. maybe u can show me someday

[NJSPEEDER]

he can show you at teh monthly meet in north jersey. we will eb in saddle brook on march 12th.
jon really is good with this stuff. he has done chips and helped with tuning on cars for several members of the board.

later
tim