What type of fuel you put in your stock TPI?
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Car: 1988 Camaro Iroc-Z
Engine: 305
Transmission: T-5
Axle/Gears: 3.08
What type of fuel you put in your stock TPI?
So, I was wondering what are you guys using for fuel in your stock TPI...The 1st owner I got the car from told me he used regular grade fuel, and so was I the past few years that I've owned it, once in a while I used primium grade, but never noticed significant difference, however, I did saw that the owner's manual recommend using high grade fuel in the TPI engines.
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Car: 1992 Chevrolet Camaro Z28
Engine: 5.7 TPI
Transmission: 700R4 Overdrive Automatic
Axle/Gears: 3.23:1 Positraction
Re: What type of fuel you put in your stock TPI?
That's what it says on my Mercedes near the gauge, Premium Fuel Required, on my Trans am it says Unleaded Fuel Only, I used 87 regular on my '87 Iroc and when I first bought my '92 Z28 I used 87, then switched to Premium (91) but then switched back to 87 89 & 91 and noticed it runs better on 91.
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Car: 1988 Camaro Iroc-Z
Engine: 305
Transmission: T-5
Axle/Gears: 3.08
Re: What type of fuel you put in your stock TPI?
It does says unleaded fuel without reference to any grade near the guage, but if you have the owner's manual, look inside and you will see that they recomend going with 91, but they also say that you can use lower grade fuel but with reduced performance. I know mercedes require you to use primium, I think its because they use higher compression engines. I know if you use regular fuel in a mercedes, the check engine light will come on.
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Car: 1992 Chevrolet Camaro Z28
Engine: 5.7 TPI
Transmission: 700R4 Overdrive Automatic
Axle/Gears: 3.23:1 Positraction
Re: What type of fuel you put in your stock TPI?
It's weird tho in my Grandmas Dodge Caravan V6 3.3L the owners manual says To use 87 regular for optimum performance and you would think that if you used 91 that would be even better right?, well the manual says the use of higher Octane 91 may result in poorer performance. That left me wondering. My Nissan Sentra runs on 87 and says Unleaded fuel only.
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Car: 1988 Camaro Iroc-Z
Engine: 305
Transmission: T-5
Axle/Gears: 3.08
Re: What type of fuel you put in your stock TPI?
I guess each manufacture have its own settings for the fuel injection system which determines what gread of fuel to use. In the owner's manual they say you have the option to use regular fuel with reduced performance because of the electronic spark control system that the TPI has...I guess when you use regular gread fuel the ecm retards the timing a little bit.
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Car: '88 Trans Am GTA
Engine: 305 TPI
Transmission: 700R4
Re: What type of fuel you put in your stock TPI?
It's weird tho in my Grandmas Dodge Caravan V6 3.3L the owners manual says To use 87 regular for optimum performance and you would think that if you used 91 that would be even better right?, well the manual says the use of higher Octane 91 may result in poorer performance.
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Car: Camaro SS
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Car: 1991 Z28 1LE
Engine: 370CID GenIII
Transmission: 4l60e
Axle/Gears: 4.33 Moser 9inch
Re: What type of fuel you put in your stock TPI?
Yeah LB9 Hit the nail on the head, and not to be a jerk but 88I-ROC ur wrong on somethin else, using less then 91 octane fuel on a late model Benz will not turn on a check engine light. The computer will retard timing as needed to prevent pre ignition but no service light unless the gas is bad i.e. watered down and causing misfires or something else of the sort. I work on Benz and BMWs for a living and you would be surprised how cheap luxury car owners are about their car. We do try to advise them to use top tier gasoline and proper octane ratings all the time though to no avail...
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Re: What type of fuel you put in your stock TPI?
you want to run the lowest octane that does not cause knock (retarded timing), and higher octane will not give any increased performance, except how fast your wallet empties.
also, with the price of gas I have found that premium fuel sits longer in the underground storage tanks and is more likely to be "bad gas" especially with the ethanol now in all gasoline.
also, with the price of gas I have found that premium fuel sits longer in the underground storage tanks and is more likely to be "bad gas" especially with the ethanol now in all gasoline.
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Car: 1988 Camaro Iroc-Z
Engine: 305
Transmission: T-5
Axle/Gears: 3.08
Re: What type of fuel you put in your stock TPI?
Yeah LB9 Hit the nail on the head, and not to be a jerk but 88I-ROC ur wrong on somethin else, using less then 91 octane fuel on a late model Benz will not turn on a check engine light. The computer will retard timing as needed to prevent pre ignition but no service light unless the gas is bad i.e. watered down and causing misfires or something else of the sort. I work on Benz and BMWs for a living and you would be surprised how cheap luxury car owners are about their car. We do try to advise them to use top tier gasoline and proper octane ratings all the time though to no avail...
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Car: 85 Trans Am
Engine: 98 Vortec 350 LT1 Cam w/ TPI
Transmission: T56
Axle/Gears: 9 bolt 3:27
Re: What type of fuel you put in your stock TPI?
Probably because the car was designed for premium fuel. If it is designed for higher octane fuel (aka higher compression) then yes you will tend to knock with 87. But if your car was designed for 87 then there is no benefit from using higher octane fuel. The L98 and LB9 I believe are both 9.0:1 CR so there is no benefit to using anything higher than 87 unless you run higher than factory timing.
My vortec has 9.6:1 and I run a stock timing table and run 87 all day long. I have never had a hint of knock even on a 100+ deg day under heavy load.
My vortec has 9.6:1 and I run a stock timing table and run 87 all day long. I have never had a hint of knock even on a 100+ deg day under heavy load.
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Car: '88 Camaro
Engine: L03 TBI
Transmission: WC T-5
Axle/Gears: 7.625 10 bolt stock 3.08's
Re: What type of fuel you put in your stock TPI?
My car is a tbi but I'm running a little more advance than stock and it runs best on 93. Back when timing was stock I didn't notice any difference between 87 and 93 until I got on it and above about 3k rpm it would pull timing and kill power when running 87. Also gotta remember these cars are old and more than likely have a good bit of carbon build up which will make the engine more prone to detonation. I know here in FL 93 is around .20 more than 87 and if you put in 10 gallons thats only $2 more so the cost is negligible IMO. I always try to run Cheveron gas because of the Techron additive they use. The concentrate they make is the only fuel system cleaner I've ever used that actually works. Also, my wife used to work at Gate Petroleum and they checked their tanks daily for water and if it was contaminated they would stop selling that grade of gas and have a truck come pump out the tank.
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Car: 1991 Z28 w/G92
Engine: 5.7 TPI
Transmission: 700R4
Re: What type of fuel you put in your stock TPI?
That's true...but you don't necessary know that (knock) on a car with ESC because it's supposed to correct for that, but you can definitely see it in the knock counts and or spark retard.
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