keithystealmaro

Hi i have just recently recieved a 89 camaro rs it has a 5.0 TBI i wanted to know what kind of horsepower and torque we are talking about stock and if it is worth hooking it up and if it is possible to do cheaply? thank you!

Rice Killer87

not sure about stock HP/TQ #'s,but its only worth it to mod if u wanna run 14's the rest of your life w/ every bolt no for it.

TBI is the worst intake setup to try and make go fast,unless its aftermarket.

keithystealmaro

ttt

njspder

TBI is a solid system for making reliable power. you can easily mod the stock 305 into the 13's without breaking the bank.
start with the "free" mods.
1. the stock ignition timing is set to 0degrees, if you advnace it a little bit to about 4 degrees before top dead center you will notice an increase in throttle response, gas mile, and overall power. i have seen people take it as far as 8degrees advanced, that is a 93octane only situation.
2. the stock throttle body can be modded for more airflow and the factory fuel pressure regulator made adjustable. the "ported TB" mod is an easy one. all you do is take the throttle body off teh car and remove teh huge lips that surround the top of the throttle bore. i usually knock them down with a dremel tool and then blend them in by hand with sand paper. when you throw it back together you can also throw an extra injecter tower gasket in to raqise teh injectors up slightly, giving more room for air to flow into the throttle body.
3. gears are a big problem in TBI cars. when you look at teh tune port cars they normally came with 3.23 or 3.42 gears(some came with numerically lowere gears, btu they are not the norm) while stock tbi's got 2.73's with the auto and 3.08's with the stick. easiest way to fix this is to go to the junk yard and look for a V6 3rd gen and check teh RPO sheet, on teh sheet you will usually find code GU6, that means teh car has 3.42 gears. take the complete rear home and put a posi in it and you have a budget 3.42 posi rear to throw in your car. in 89 you have electronic gauges i believe, if you find a car with teh correct gears that has wires instad of a cable coming out of the vehicle speed sensor in teh tranny you are going to want to grab the speedo gears as well so that yours will read correctly. if you don't find the speedo gears at the yard you can get them at your local gm parts supplier as service parts.
4. the biggest thing holding back teh stock tbi system is honestly the cam. it is an absolute joke, far smaller than the cam that came in any of the "performance" V8's gm offered. a cheap fix for this is a stock LT1 cam. you can normally find them on teh web for around $50 and the rest of the stuff to do a proper install yourself is only about 150-200bucks. it will make an incredable difference in your cars power band and can be done with hand tools and a few friends in a weekend.
5. edelbrock and holley both offer upgraded intakes that are specifically designed for tbi. the edelbrock is teh more direct fit, the holley has a more volume for more top end power and is bored to allow a larger tb for future upgrade. both cost about the same, in my experience i woudl choose teh holley so that you can upgrade to a stock 454TB or holley 350replacement tb in the future.
6. computer tuning is teh only way to truely take advantage of your mods. it is cheaper and easier to do yourself than you woudl ever think possible. you can actually get started burning chips for about 150bucks if you already have a laptop.
7. exhaust is a common mod, but do it right. buy parts that are for 3rd gens equiped with a single 3inch cat. teh parts that companies sell that they say are for tbi all use smaller tubing that is insufficiant for stock, much less a modded car. also make sure you get some good headers. cat backs at noise, headers add power.

hope this helps. if you have any questions hit me up on AIM: njspder

and tell everyone who talks about how bad tbi is to dislodge their heads from their asses and see that any system can support a serious street motor with proper parts matching.

later
tim

nj85z28

i agree with tim, there is serious upgrades to the TBI http://www.goingfaster.com/spo/modthel03.html

njspder

sorry the end of my post turned into a rant. it jsut pisses me off when people think tbi is inferior. i went 14.20's in a stock cam adn stock chip car years ago and one of my best friends runs a full weight 91rs with a 350HO crate motor to 13.4's at 104mph(road racing style suspension doesn't hook for ****). all he has on the crate motor is a performer rpm intake and an upgraded tb/injector set, he even uses teh stock computer still with his own home grown custom programming.
TBI can get it done as well as any other system.

later
tim

Rice Killer87

nice link.

when i said trying to make it go fast,i was talkin mid to low 13's,or high 12's....thats "fast" to me for a TBI car. the links off of that website you posted,the 400HP 305,the 343 HP 305,and the 2nd 325 HP 305 (i didnt look at the first 2 links) were with carb'd 305's. not TBI,but close.

ive read that the TBI motors had horrible heads,along with a tiny cam. im not preaching what ive read is right and please correct me if im wrong.

ive also read that the TBI computer isnt real good for tuning for major mods,such as a healthy cam.

and if i wanted to run something "different" than everyone else,it would be something like a twin turbo LS1 Fiero,not a TBI F-body.

brians96Z

Let us know how it turns out. I have a 90 RS myslef, and would like to know. Mine is bone stock except for a Dynomax Cat-back system.

njspder

if you want 12's teh formula is really simple.
1. 4.10 gears and a posi
2. 3000-3400 stall
3. LT4 Hot Cam or similar. you can actually get away with a regular LT4 cam if you want low 13's, one of the comp cams extreme energy grinds would also work well
4. torker intake with TBI adaptor and gasket matched
5. World products makes a torquer 305 head if you like iron, personally i would go with a set of vette l98 heads with a mild port+3/5angle valve job+gasket matched to intake. end result is a similar price but the vette heads drop a bunch of weight
6. either factory 454tb or holley 350 replacement tb.
7. stock computer with a custom chip(the stock tbi computer in your car is perfectly capable of handling whatever you want to throw at it with a proper chip)
8. put together a proper suspension to keep it all hooked up and happy

hope this helps

later
tim

un4giv3n

let's say it makes 300 horses and 200 ft/lbs. of torque. In the other RS, we have a engine tuned for torque. Let's say it makes 200 horsepower and 300 ft/lbs. of torque. Guess which one is going to be faster ...? Right. The 200 horsepower, 300 ft/lbs. torque car will run away from the 300 horsepower / 200 ft/lb. car all day long, without effort.

is he serious??? and i wanna know how u "tune" a car for horsepower instead of torque? and how the hell do you get 300hp with 200 ft/lbs of torque? is it a 4 banger? IMO horsepower matters most, torque is for trucks.

njspder

torque is what exists, it is real. it is measurable.
the way to build more torque or hp into an engine is to control it operating range. since normally torque occurs at lower rpms, if you build an engine to spin to a higher rpm it will create a higher hp value.
teh rpm range of these values is also reliant on teh displacement of teh engine. bigger cubes makes more torque at a lower rpm, which means that the related hp will be at a lower rpm too.

later
tim