Why is my TBI slow?
#1
Why is my TBI slow?
First of all I'm sorry if I put this thread in the wrong firms, but anyhow, I have a 89 camaro rs that came with a 305 but the engine is different than a 305 in my friend's identical car, the dipstick curves, why?
Now for my big question, I drove it down the 1/4 mile and I really pushed it and it got a 16.8 1/4 time and a 9.45 0-60 time. These numbers a re crappy considering the engine seems to have been rebuilt. It also has a t5 tranny and good rubber.<O</O
Why do you think I got such slow numbers, what could be wrong with it, or is this normal?
well I guess I should have been more clear. The stock 305 isn't all that stock. I have a knn filter, flowmaster exaust, race shocks, 255 bfgs in the rear and my driving is good enough, yet this thing gets suck ****ty sumbers. I have a friend with a stock 89 firebird with no mods at all and he gets better times.
Is it possible that my car feels slow just cause something like a bad fuel filter or something.
I know this thing should get better numbers and from what I read, other stock 305's are much faster.
<O</O
<O
Thanks for your input.<O
Now for my big question, I drove it down the 1/4 mile and I really pushed it and it got a 16.8 1/4 time and a 9.45 0-60 time. These numbers a re crappy considering the engine seems to have been rebuilt. It also has a t5 tranny and good rubber.<O</O
Why do you think I got such slow numbers, what could be wrong with it, or is this normal?
well I guess I should have been more clear. The stock 305 isn't all that stock. I have a knn filter, flowmaster exaust, race shocks, 255 bfgs in the rear and my driving is good enough, yet this thing gets suck ****ty sumbers. I have a friend with a stock 89 firebird with no mods at all and he gets better times.
Is it possible that my car feels slow just cause something like a bad fuel filter or something.
I know this thing should get better numbers and from what I read, other stock 305's are much faster.
<O</O
<O
Thanks for your input.<O
Last edited by 89rskamaro; 04-10-2006 at 05:22 PM.
#2
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Car: 1990 Camaro RS
Engine: 305 TBI (L03)
Transmission: 700R4 (MD8)
Axle/Gears: 2.73 Open (GU2)
I don't know. I think maybe it's because it is a completely stock L03 motor. They weren't designed really for speed they were meant for improved fuel mileage when gas was a whopping $1/gal back then. Trust me, in stock form it will be slow, but when you put some mods on it it will really wake it up.
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like he said minus all the smilies..... they werent really ment for speed. Reliability and fuel economy were the key factors.
Headers, catback, open element, free tbi mods, higher rear gears, little suspension, and a cam swap will put much happier numbers on the boards at the track.
Plus it has a lot to do with your driving abilites also ... like your launching and shifting
Headers, catback, open element, free tbi mods, higher rear gears, little suspension, and a cam swap will put much happier numbers on the boards at the track.
Plus it has a lot to do with your driving abilites also ... like your launching and shifting
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Car: 1990 Camaro RS
Engine: 305 TBI (L03)
Transmission: 700R4 (MD8)
Axle/Gears: 2.73 Open (GU2)
The smilies were sort of a sarcastic statement. I apologize to anyone whom I offended..........
Anyways... something very easy you could do if you don't care about it being street legal is do some massive weight reduction. I'm talking massive.... carpet, all seats but yours, headliner, panels, dash. Hey, when civics have 170 HP they run 14's all day. If you can get your car below 2500 lbs, you would have a field day with that thing.
But if you want to be smart and logical, just put an open element on it for now. That should please you until you want to put a cam in, and some gears, which takes alot of work with chip burning and all (not the gears part). I think that the TBI is an enormously good engine that with proper maintenance can last years. It gets me back and forth to work every day while getting about 24 MPG... not bad!
Anyways... something very easy you could do if you don't care about it being street legal is do some massive weight reduction. I'm talking massive.... carpet, all seats but yours, headliner, panels, dash. Hey, when civics have 170 HP they run 14's all day. If you can get your car below 2500 lbs, you would have a field day with that thing.
But if you want to be smart and logical, just put an open element on it for now. That should please you until you want to put a cam in, and some gears, which takes alot of work with chip burning and all (not the gears part). I think that the TBI is an enormously good engine that with proper maintenance can last years. It gets me back and forth to work every day while getting about 24 MPG... not bad!
#5
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Car: 91 firebird
Engine: 350
Transmission: t-56
That is slow for a 5 speed LO3.
Don't take this the wrong way but it might be your driving and it might be the "Rebuild" or the ar might just need a tune up, if it still has a stock 20 year old cat on it might be part of the problem too. MOST LO3 T-5 cars if running right and driven right will be in the mid to high 15's. Big clutch dumps and spinning tires don't make for fast times, but sure are tire smoking fun. If you want more power start with the exhaust. Save up some money because it not going to be cheap like older cars will be and do the WHOLE exhaust system headers, cat, and catback. Look for some good header like the Hooker 2055 or the SLP headers 3inch cat and catback. Buy exhaust parts for a TPI car and do not get a 2 1/2 system. That will wake up the car! Even more so with some tuning.
Don't take this the wrong way but it might be your driving and it might be the "Rebuild" or the ar might just need a tune up, if it still has a stock 20 year old cat on it might be part of the problem too. MOST LO3 T-5 cars if running right and driven right will be in the mid to high 15's. Big clutch dumps and spinning tires don't make for fast times, but sure are tire smoking fun. If you want more power start with the exhaust. Save up some money because it not going to be cheap like older cars will be and do the WHOLE exhaust system headers, cat, and catback. Look for some good header like the Hooker 2055 or the SLP headers 3inch cat and catback. Buy exhaust parts for a TPI car and do not get a 2 1/2 system. That will wake up the car! Even more so with some tuning.
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#8
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Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Originally Posted by Crusin' 1980's
Thats what i have on my 305TBI
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Car: 1999 Yamaha Banshee
Engine: 379cc twin cyl 2-stroke stroker
Transmission: 6 spd manual
Axle/Gears: 14/41 tooth
Originally Posted by MikeDirntRulez
Anyways... something very easy you could do if you don't care about it being street legal is do some massive weight reduction. I'm talking massive.... carpet, all seats but yours, headliner, panels, dash. Hey, when civics have 170 HP they run 14's all day. If you can get your car below 2500 lbs, you would have a field day with that thing.
But if you want to be smart and logical, just put an open element on it for now. That should please you until you want to put a cam in, and some gears, which takes alot of work with chip burning and all (not the gears part). I think that the TBI is an enormously good engine that with proper maintenance can last years. It gets me back and forth to work every day while getting about 24 MPG... not bad!
But if you want to be smart and logical, just put an open element on it for now. That should please you until you want to put a cam in, and some gears, which takes alot of work with chip burning and all (not the gears part). I think that the TBI is an enormously good engine that with proper maintenance can last years. It gets me back and forth to work every day while getting about 24 MPG... not bad!
#12
well I guess I should have been more clear. The stock 305 isn't all that stock. I have a knn filter, flowmaster exaust, race shocks, 255 bfgs in the rear and my driving is good enough, yet this thing gets suck ****ty sumbers. I have a friend with a stock 89 firebird with no mods at all and he gets better times.
Is it possible that my car feels slow just cause something like a bad fuel filter or something.
I know this thing should get better numbers and from what I read, other stock 305's are much faster.
Is it possible that my car feels slow just cause something like a bad fuel filter or something.
I know this thing should get better numbers and from what I read, other stock 305's are much faster.
#13
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Car: 1988 SC Camaro
Engine: 305 TBI
Transmission: 700-R4
maybe you're losing acceleration/speed because its a manual. In between shifts i would think the car would slow down a bit. Have you changed all the filters and are all the sensors good? Plugs, wires & rotor? check your timing?
#14
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Originally Posted by 89rskamaro
well I guess I should have been more clear. The stock 305 isn't all that stock. I have a knn filter, flowmaster exaust, race shocks, 255 bfgs in the rear and my driving is good enough, yet this thing gets suck ****ty sumbers. I have a friend with a stock 89 firebird with no mods at all and he gets better times.
Is it possible that my car feels slow just cause something like a bad fuel filter or something.
I know this thing should get better numbers and from what I read, other stock 305's are much faster.
Is it possible that my car feels slow just cause something like a bad fuel filter or something.
I know this thing should get better numbers and from what I read, other stock 305's are much faster.
It sounds like the car needs a good tune up. Check and replace all ignition components. Replace all filters. Check feed line fuel pressure and base timing (with EST unplugged).
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Car: 89' Iroc-Z G92
Engine: TPI 305 G92
Transmission: T-5
Axle/Gears: Limited 9 bolt, 3.45
check the casting number on the engine.. they may not be an L03.. if your dipstick is angled it might very well be a 140hp Lg4 with the L03 top end.
Just my 2 cents..
edit... pull your casting number.. check it here... http://www.mortec.com/
Just my 2 cents..
edit... pull your casting number.. check it here... http://www.mortec.com/
Last edited by Mcdamit; 04-10-2006 at 11:59 PM.
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Car: 92 Camaro RS
Engine: 350
Transmission: stock
Axle/Gears: stock
Originally Posted by 89rskamaro
well I guess I should have been more clear. The stock 305 isn't all that stock. I have a knn filter, flowmaster exaust, race shocks, 255 bfgs in the rear and my driving is good enough, yet this thing gets suck ****ty sumbers. I have a friend with a stock 89 firebird with no mods at all and he gets better times.
Is it possible that my car feels slow just cause something like a bad fuel filter or something.
I know this thing should get better numbers and from what I read, other stock 305's are much faster.
Is it possible that my car feels slow just cause something like a bad fuel filter or something.
I know this thing should get better numbers and from what I read, other stock 305's are much faster.
#18
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Originally Posted by darkangel777
What is est and does it need to be unplugged to time properly?
The EST is located behind the passenger side strut mount and must be unplugged when you set your base timing. Refer to the stickies above for more info and pics.
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Car: 91 Camaro RS
Engine: 305 TBI (L03)
Transmission: T5
Axle/Gears: 3.73 Truetrac posi
With a T5 trans, stock rear gears, engine/ignition in good tune, and the limited mods you've got, you should expect times in the high 15's or low/mid 16's. That's assuming good launches, shifts above 5000 rpm, and you don't live in Denver! Headers and rear gears will give you the biggest timeslip improvements without getting into the motor.
#20
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Car: 91 Camaro RS
Engine: TBI
Transmission: 700r4
Originally Posted by 91RockS
With a T5 trans, stock rear gears, engine/ignition in good tune, and the limited mods you've got, you should expect times in the high 15's or low/mid 16's. That's assuming good launches, shifts above 5000 rpm, and you don't live in Denver! Headers and rear gears will give you the biggest timeslip improvements without getting into the motor.
In reality your combo is stock, get a lil serious, headers, cat, 3", open element, port teh tbi and maybe look into getting into the internals of her
#21
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Car: 1991 Firebird
Transmission: T5
Axle/Gears: 3.42 w/auburn racers diff
i feel ya bud
I got a 91 lo3 bird with a t5 and 3.08 gears in back. I took it to my local track after i bought it and the best i could get out of it was a 16.7 I could not get traction, and with my bald 1 tire fire i was spinning just about all the way into second. I would start with the basics. Check the Timing, mine was at 0 and then i advanced it to about 4 degrees, that helped wake it up a bit. Make sure your plug wires, plugs cap and rotor are in good shape, mine all needed to be replaced. Im hoping to break into the 15s lol but ill have to wait till i find a new t-5.
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Car: 88 Chevy Z24
Engine: 2.8 TPI V6
Transmission: M5
damn man, i just sold a stockish 91 honda prelude si because i thought it was too slow, i couldnt get better than 17 flat at 82mph..... i was lookin at gettin a 3rd gen camaro 305 5 speed but apparently it wont necassarily be any faster than a freakin 4 cylinder?!?!?!
#26
My 88 305 "feels" fast, but i'm sure it's just the torque. Hell my saturn ran 14.9-15.2 consistently with just bolt ons and a mild head porting. Tires will make a big difference. Now that the turbo setup is almost finished on the saturn I am starting a build for the camaro.
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Car: 91 firebird
Engine: 350
Transmission: t-56
When I first got my car in 97 it was a Lo3 5-speed it ran some thing like a 16.8 or so with 87k on the speedo and a cheapo 2 1/2 single pipe back wood exhaust with 2 glasspacks on it. A tune up a new cat from crap-o-zone and a new fuel pump and a mr gasket open air filter put me at around 15.8
#28
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Car: 91 Camaro RS Convertible
Engine: 305 TBI
Transmission: 5-Speed
Axle/Gears: 3.42
Originally Posted by 91RedFirebird
When I first got my car in 97 it was a Lo3 5-speed it ran some thing like a 16.8 or so with 87k on the speedo and a cheapo 2 1/2 single pipe back wood exhaust with 2 glasspacks on it. A tune up a new cat from crap-o-zone and a new fuel pump and a mr gasket open air filter put me at around 15.8
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Car: 4 Mopars total
Engine: Pentastar power
Transmission: T/F and New Process
Axle/Gears: Three 8 3/4's & one 9 1/4
The L69 in my 84 MSE ran a 14.96 bone stock with 113,000 miles on it. I wonder what shell run with the headers and full exhaust, and 2200 converter. The L69 is the ONLY 305 I would ever own.
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Car: 89' Iroc-Z G92
Engine: TPI 305 G92
Transmission: T-5
Axle/Gears: Limited 9 bolt, 3.45
Originally Posted by 84L69TA
The L69 in my 84 MSE ran a 14.96 bone stock with 113,000 miles on it. I wonder what shell run with the headers and full exhaust, and 2200 converter. The L69 is the ONLY 305 I would ever own.
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Car: Trans AM
Engine: 305 TBI LO3
Transmission: W/C T-5
Axle/Gears: 3.42 Open
LO3 TBI, L98 cam, intake manifold, open element, cat, dynomax cat-back, 3.42 open t-5spd, rear seats out, 15.2@89mph, with a 2.1 60', ur 60 is freakin junk. 9 seconds to go 60'(im assuming u think the 60 on hte slip is 60mph but its a foot mark)
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Car: 1991 pontiac Firebird
Engine: 305 tbi, Lo3 (for now)
Transmission: auto
Axle/Gears: stock (for now)
Im in Bristol, notorious for slow times, and bone stock my L03 bird ran a 16.8. Its also an auto. It was in good tune, and completley stock. I was hoping for a high 15 this year, but it isnt looking good.
#34
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Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Originally Posted by 84L69TA
The L69 in my 84 MSE ran a 14.96 bone stock with 113,000 miles on it. I wonder what shell run with the headers and full exhaust, and 2200 converter. The L69 is the ONLY 305 I would ever own.
Are you sure you wouldn't take my old 305! 15.17 @ 96.32 MPH with a 2.23s 60' time through open cut-outs was the best time it ever turned. (In a 5,300 lbs van)
#35
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Car: 1991 camaro RS
Engine: CharlesOdoryOB
Transmission: 82513892892
Axle/Gears: pbr disc 3.27 nine bolt
well i just ran 16.9@81 2.5 60foot
305 tbi auto with 89k miles
this is why tbi is getting junked for tpi
305 tbi auto with 89k miles
this is why tbi is getting junked for tpi
#36
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Car: 91 firebird
Engine: 350
Transmission: t-56
Originally Posted by Azrael91966669
well i just ran 16.9@81 2.5 60foot
305 tbi auto with 89k miles
this is why tbi is getting junked for tpi
305 tbi auto with 89k miles
this is why tbi is getting junked for tpi
#37
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Car: 91 Camaro RS Convertible
Engine: 305 TBI
Transmission: 5-Speed
Axle/Gears: 3.42
Originally Posted by Azrael91966669
well i just ran 16.9@81 2.5 60foot
305 tbi auto with 89k miles
this is why tbi is getting junked for tpi
305 tbi auto with 89k miles
this is why tbi is getting junked for tpi
#38
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Car: 1991 camaro RS
Engine: CharlesOdoryOB
Transmission: 82513892892
Axle/Gears: pbr disc 3.27 nine bolt
well looking at motor trends old test the best they got out of a 5speed tbi was 16.1 my reaction time sucked .6 but still i see why everone says these cars are slow my 3.1 v6 kills this car
i just wanted a baseline to see how slow .
every 305 tpi ive drive blows the doors off this car so thats why im putting the tpi on better heads better cam better injection system as this is just depressing
i just wanted a baseline to see how slow .
every 305 tpi ive drive blows the doors off this car so thats why im putting the tpi on better heads better cam better injection system as this is just depressing
Last edited by Azrael91966669; 04-22-2006 at 10:42 PM.
#39
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Car: 91 Camaro RS Convertible
Engine: 305 TBI
Transmission: 5-Speed
Axle/Gears: 3.42
Originally Posted by Azrael91966669
well looking at motor trends old test the best they got out of a 5speed tbi was 16.1 my reaction time sucked .6 but still i see why everone says these cars are slow my 3.1 v6 kills this car
i just wanted a baseline to see how slow .
every 305 tpi ive drive blows the doors off this car so thats why im putting the tpi on better heads better cam better injection system as this is just depressing
i just wanted a baseline to see how slow .
every 305 tpi ive drive blows the doors off this car so thats why im putting the tpi on better heads better cam better injection system as this is just depressing
#40
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Car: 1991 RS Convertible
Engine: 96 LT1
Transmission: T5
Axle/Gears: 3.45 9-Bolt
I dont like to admit this... But when I first got my car 4 years ago... The best i could get out of it was a 17.1! That was a bone stock convertible w/ an auto & 2.73 gears.
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Car: 87-Z r.i.p & 93-Z sold 99s-10
Engine: 305 TPI , 350 LT1, 2.2 4cylinder
Transmission: 700 R4, 4l60, ?
Tbi is not the best flowing setup out there....some people just switch over to carb since there's plenty of good inexpensive intakes and such. And my bone stock tpi went 15.4 but with headers and free mods went 14.9 so tpi does have pretty good power. And i have seen some v-6 camaros beat a couple of 305 tbi, hell even one with a 3rd gen 2.8 stick almost got me in a race...i was pretty suprised how quick they are, but i was still able to beat him.
#42
Thanks alot for your input. Now that I see that I am not the only slow camaro here, I'm feeling a little better. I will get a few other mods done and get a different driver, just in case and check if things got faster.
thanks all
thanks all
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