killacamaro

iTrader: (5)

hey guys i just pickd up a 91 camaro rs 305 v8 tbi. i am concernd on what to do to this car. a few peeps say get rid of the tbi and go carb. others say stick with the tbi and get a carb intake manifold and an adapter for the tbi. what do u guys think i should do? i basically want a street racer/daily driver.

DLV555

iTrader: (1)

A lot of people will tell you to ditch the TBI for the carb. They are usually just ignorant and are regurgitating what they've always heard since TBI is a very misunderstood induction system. EFI offers benefits that you just can't find with carbs. Don't get me wrong, I like carbs. 2 of my 3 cars are carbed. Indulge yourself in all the EFI tuning related material available on this site, particularly the stickies in this section and you will learn more about TBI than you can imagine. It is extremely interesting stuff and there are several very learned members of this board that can offer endless advice on the topic.

funkdubie

stick with what you have...add exhaust system, ditch the clutch fan if you have one and tune from there...maybe add a cam and different heads later.

RFmaster

acamaro

By going to carb you will be reducing vehicle value to zero by making it completely un-resalable. Let me remind you that we are in 21st century and thanks to Eco-****'s, led by Al Gore, and the rest of the tree huggers sooner or later local government will be crawling up your exhaust pipe and emptying your wallet. There is little (I would say no chance) chance that a carburetor will be able to deliver emissions applicable to '91 model year car. There are many performance upgrades that you can do to a TBI which are impossible for carb to achieve. Read stickies, check some serious FI equipped rides - for example Fast355 5500 G20 van and many other fine examples. Ask questions. FI requires slightly different approach and I am not going to beat around the bush - a learning curve.


//RF

killacamaro

iTrader: (5)

thanx guys, any other info u can give me and lead me to, any stickies or posts that can help me out. or what to search for on modding my TBI? thanx

BMmonteSS

Read all the stickies at the top of the page.....

diy tuning + full exhaust + gears = high 14's. These cars are pretty restricted so there is lots to be gained.

Throw in a cam and head swap and you'll be in the high 13's.

Next throw in a 350 bottom end and you'll be looking at bottom 13's.

KrisW

iTrader: (5)

1. Gain the most from your exhaust possible; DUMP THE CAT-FORWARD! Your manifolds and y-pipe are possibly THE MOST RESTRICTIVE EVER MADE BY CHEVY! I know, it's hard to believe, but it's true. Even manifolds and a y-pipe from a TPI car make a DRIVEABLE DIFFERENCE. Anyway, headers, y-pipe and high flow cat will do you nicely. Then, add a nice flowing cat-back system.

2. Next, you need good flowing, upgradeable heads. You can port the crap out of your heads but you can't re-use them for a 350 in the future. Some day you may want to upgrade. On a budget, you need a set of 87-up LG4 carb heads or 5.0 liter TPI heads with 1.94 intake valves and a little port work. You will think you put another engine in your car.

3. Your cam just flat sucks. No two ways around that one. Again, even a stock TPI cam is a HUGE upgrade. I think the LT1 cam works great, but an L98 cam is good, too. Your computer will still be happy with one of those cams. Your cam is so small everybody here calls it the "peanut" cam...

4. Drop the tank and put in a TPI or later Vortech fuel pump. Your stock fuel pressure regulator will take the extra flow and pressure just fine and your engine will run better.

After you've done all this, THEN you'll be ready to talk about 670 cfm throttle bodies, 2" throttle bores, and aftermarket intakes.

And then you'll be ready to burn your own chips and go nuts!

Good luck!

killacamaro

iTrader: (5)

hey kris thanx for the info will deff look into this, do u really need a high flow cat? or can i run straight pipe from the y-pipe?

KrisW

iTrader: (5)

I don't ever recommend dumping the cat anymore. Too many smog ***** out there watching what we do (yes, I am paranoid) and say. I have gutted cats and run 3" pipe straight through them but they are always there on my cars now.

You really will get the biggest pickup by ditching your manifolds and y-pipe. It is a driveable difference that you can feel!

killacamaro

iTrader: (5)

yeah im gunna do shorty headers to custom y-pipe? sounds good and then run straight pipe to muffler, **** the cat i can get an illegal inspection anyday,... should i do shorty headers or long tube?

bigj350

iTrader: (1)

Shorty, there easier.