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DFJ6000
10-13-2004, 03:04 PM
Hey, im lookin at buyin a 1990 RS camaro, with a 305, underdrive pulleys and a chip. what i wanna kno is, whats better TBI or TPI? from what i heard TBI is low end power and TPI is top end? is this true? And shood i switch out a TBI for a TPI, sorry if like a million other people have asked this before...lol

Pepsicola300
10-13-2004, 06:13 PM
check out www.thirdgen.org

TPI is better than TBI.....

Knyghtmare
10-13-2004, 06:37 PM
In my opinion they are both boat anchors... But I would rather have TPI over TBI. Trottle-Body Injection is just flat out crap for anything performance. I had a 305 TBI and it was great for stock and the stock 220hp... but for anything performance is not worth it through a TBI. TBI's do have a lot of low end torque but nothing performance.

To answer your question, yes, I would change your top end. There are many options. They just all depend on your budget. :)

scattergun
10-13-2004, 07:30 PM
Is that 1990 RS a 5 speed or automatic? Chevy 305's are garbage.They are fine for daily driving and gas mileage but thats about it. Consider swapping to a 350ci or larger engine if you buy the car and want to go faster than 17 seconds in the quarter.

BadAzzGTA89
10-13-2004, 07:43 PM
TPI all the way waayy more torque and throttle responce!!!IMO! Just look at my sig and it tells all GTA only came TPI and the same for the (true)IROC'sHell i make way more torque than HP.Just my 2 cents

DFJ6000
10-13-2004, 10:02 PM
The car is automatic, I believe they came a 700R4? The interior is pretty much little to none, so its light as all h3ll, its lowered 2 inches and has a strut tower brace as well, dude wants 800 dollars. Seemed pretty fast to me, but then again ive never owned anything that broke 16 seconds lol.

DFJ6000
10-13-2004, 10:06 PM
from what i hear the guy said he raced a 383 stroker 64 impala, and was only a car lenth behind, a car lenth seems faster than 17 seconds? and this dude isnt the type of dude whos fulll of ****, but ya never kno? thats why im askin how true his statement was.

Prince Valiant
10-13-2004, 11:28 PM
If it's a tpi car with an auto and in good shape, you can reasonably expect mid to low 15's...but the 170hp TBI cars are dogs. With a 5 speed maybe they ran high 16's on a good day.

The late third gen camaro's were my rivals back in the early 90's...the last couple of years they were out I had a devil of a time with the 350 equipped models...was a drivers race against them from a "dig". Any 305 models were fairly easy prey...high 14's with a stick were the best 305's. This was against my modified Daytona Shelby Z....went low 14's at 99mph.

scattergun
10-14-2004, 12:03 AM
For $800, sounds like a bet if the body is in halfway decent shape.3rd gen F body's have alot of potential.I am on my 6th one,can't seem to get away from them.You can find decent ones cheap,and throw a motor in them and have a halfass quick car.They handle great in stock form,and with mods will pull more than a 1g on the skid pad.As long as it isn't rusted out(pay good attention to the strut towers and floor pan),and hasn't been majorly wrecked,I would buy it.For some quick,cheap power,find a good running TBI 350 out of a 87-95 Chevy truck and throw it in,along with the ECM out of the truck.The ECM plugs directly in and works fine.You can find these motors for less than $500 anywhere.I had a 88 RS that was a 305 TBI and 5 speed.I did this and easily had a 15 second ride for cheap.Throw a small cam in and a decent free flowing exhaust and shorty headers for another $500 and get into low 15's,high 14's.You would be able too at least smoke most ricers out there. :thumbsup

DFJ6000
10-14-2004, 01:33 AM
hell yeah scattergun, sounds like a kick ass idea thanks for the info bout the strut towers, i kno the car sat a while tho cuz they broke the rear axle while runnnin from the cops, thats basically why its so cheap, he's goin to jail. the only thing that worrys me is that i kno that most to all the miles that are on the 305 are beat me miles.

scattergun
10-14-2004, 04:38 AM
If you buy it, I have a 3.42 gear 10 bolt rear out of my T/A,that I swapped for a disc brake borg warner.I'll sell it to you for a decent price. If you don't buy it,would you consider hooking up a brother? I would give you a finders fee.

DFJ6000
10-14-2004, 03:06 PM
yeah man mos def if i dont buy ill hook a brotha up, but i think ima buy it this weekend, hell yeah bout the rear end ill buy it, the one thats one there was just rebuilt but makes a clunk noise? the car is all black with limo tint, but like i said before there is no interior, it has a z28 front clip the whole car itself looks tuff. i rode in it and it seemed ungodly fast for a 305.

Knyghtmare
10-14-2004, 05:28 PM
You could easily build a nice TPI motor for fairely cheap. A 350 roller block stroked or not. Some nice aftermarket aluminum heads and a big lumpy cam, that would really make it purr. You can even upgrade the top end with an LT1 intake for pretty cheap. Those SteathRams and other aftermarket intakes can be pretty expensive... ask Scales. I have pleanty of ideas to built up a nice TPI motor. There are pleanty of options out there as well.

BadAzzGTA89
10-14-2004, 05:43 PM
I have the 350 tbi in my 87 gmc suburban for sale!!!Hell if that big beast can still spin both big ass rear tires it shoild be just fine for a maro!!Oh yea and it hauls hella ass in four wheel drive .PM me if ya want to check it out!!!

DFJ6000
10-14-2004, 10:43 PM
what r ya lookin for prices for the 350? I also have a 71 nova im lookin to do something with. anyone kno how hard it is to find a used LS1? or how much that wood be?

BadAzzGTA89
10-15-2004, 08:40 AM
$200.00 complete engine with the ECM. I will pull it for ya!! Cause i have use of a forklift.

Brian

PB86MCSS
10-15-2004, 10:28 AM
Just look at my sig and it tells all GTA only came TPI and the same for the (true)IROC's

Many IROC's came TBI powered and carbed before TBI replaced it as the base setup on the 305. Not all are TPI powered but most...same with Formula's...I'd assume all GTA's are TPI powered.

305 TPI/5 speed combos are nice and can be relatively quick. Obviously a 350 is a hell of alot better ;). My LS is TPI powered and I don't think it sucks, EFI is nicer than the carb for a semi-daily driver and has nice torque :D. Still a 305 for now though, but spring 05' it will be 350 powered.

For performance, TBI sucks. If you just want a daily with decent mileage, I think a 305 TBI is ok.

DFJ6000
10-15-2004, 12:08 PM
is there nething wrong with the 350? if its all good, hell yeah ill buy it, just need a lil time to save up lol im a minimum wage millionaire tryin to get a cool car here lol

BadAzzGTA89
10-15-2004, 12:18 PM
Nope she is strong !!Just the body is going away

ccas
10-15-2004, 05:45 PM
Where were you a month ago with this engine!! I just bought Knyghtmares old 305 for that. Runs good though, so I can't complain. Knyghtmare, I'll give you a call sometime late next week btw about that ecm.

DFJ6000
10-17-2004, 01:07 PM
this has nothing to do with an F-body i just fgured id post it here since were on the topic of a TPI, how hard do you think it wood be to put that TPI 350 from dudes suburban in my 84 c20 chevy pick up????

BadAzzGTA89
10-17-2004, 01:44 PM
Well the engine in the suburban ia a TBI not TPI .TBI would be alot less hassle as far as just putting new engine mounts and doing a lil wireing!!
TPI well you would have to convert said TBI engine to TPI!And a hell of a lot more wireing involved!!PB86MCSS has done a simular swap to his LS and can tell you about the wireing madness!! :thumbsup

DFJ6000
10-17-2004, 02:56 PM
i dont think i even need new mounts, the truck currently has a 305 so woodnt it match up?

BadAzzGTA89
10-17-2004, 03:08 PM
Yea should match right up!!!!

DFJ6000
10-17-2004, 03:12 PM
ur engine is a 350 tho right? ur sure of it?

rsscoty
10-17-2004, 03:53 PM
350 or 305 either way it will bolt right in. All you have to do is the wiring for the computer. I'm thinking of doing the same thing. I want to take my 305 and tbi system and put into a 70's chevy pickup, then bolt a cadi 501 in my rs.

That way I will have a dependale truck with decent economy, and one helluve a fast camaro :banana

Scoty

MitchMeister-
10-18-2004, 10:11 AM
tbi.. pfft. tpi.. pfft. mfi.. pfft. ill take my full carburated 383 anyday over fuel injection... :rockwoot:

unless its the 305 boat anchor i have in it right now.. . . :fire

PB86MCSS
10-18-2004, 11:26 PM
Carbed 383. :rockwoot:

A TPI conversion isn't terrible, I converted it to a car that was carburated from the factory, so converting a TBI vehicle should definatley be easier! TPI swaps are relatively common, as LT1's are becoming. Gotta sit down with wiring schematics between both cars(the donor and donee) and figure it out. Or an aftermarket harness such as Howell or Painless, but I'd save money and just use the GM one if possible. TPI looks better under the hood, cleaner than the CCC-Carb engines for sure with emmissions stuff, and EFI is smoother and better for a daily.

Plus TPI setups can be had relatively cheap....a guy who works at Jax seat covers off of 6th and Howard saw my LS and a TPI sticker I have, got to talking...he has a 86-87 305 TPI motor with harness and wiring hes looking to get rid of if interested. Not much needs to be changed if swapping to a 350, just the injectors/PROM/ESC/knock.

DFJ6000
10-19-2004, 02:53 AM
dam you guys are smart as all hell when it comes to cars, and i thought i knew my shi7 pretty good, :thumbsup thanks a lot

TransAm12sec
10-28-2004, 12:35 AM
A TPI is a mult port fuel injection system. Its intake has long runners, 20 some inches I believe for low end power. The design is not usefull for higher rpms(above 4500).

Here's an interesting picture of a stock tpi intake(besides the color)
http://www.ghostwheeltech.net/Ken-tpi-70-1.jpg

The tbi uses ?2? fuel injectors in the middle of the manifold.
Here's a pic without an air cleaner on.
http://www.thirdgen.org/techbb2/showthread.php?s=&threadid=227281
http://memimage.cardomain.com/member_images/12/web/528000-528999/528874_26.jpg

MitchMeister-
10-31-2004, 03:05 PM
lol i have that crap tbi stuff in my jimmy. try changing the valve covers on one of those

MitchMeister-
10-31-2004, 03:07 PM
lol i have that crap tbi stuff in my jimmy. try changing the valve covers on one of those. ive never seen so many vacuum lines in my life.