truckguy

Was really low on gas ..engine was dying on my way home. Used some of my go kart gas, which is 87 octane so I can get to the station.

I barely poured like a dollars worth, stopped bc I realized it was 87.
I want this engine to last around 2-4 years, but only driving once a week and maybe some car meets. As for my driving style, like to rev high sometimes , but not excessively.

Is 87 fine for this engine use or should I go with higher?

thtanner

iTrader: (1)

91

TPI ECMs are tuned for it

antoine

89 octane is what it requires but you can run 87 safety as long as your timing is stock°6

paulo57509

The 1987 owner's manual states that TPI engines should use premium unleaded fuel with an octane rating of at least 91.

87 octane can be used but there will be reduced acceleration performance.

92GTA

iTrader: (11)

I never got any pinging or knock on my LB9 with 87 according to my data logs. I actually got much better mileage using 87 compared to 91.

If you aren't daily driving it and only using it once a week, by all means use 91.

Bob88GTA

iTrader: (2)

Mine LOVES Sunoco 93 Ultra

Fire"Dutch"Bird

iTrader: (1)

Here in Europe, I use 102 octane (RON) in my '88 TPI.... available at some stations as Competition 102.
Contains no ethanol, and that's the most important aspect in my case, as I hardly drive my car these days anymore...

Bob88GTA

iTrader: (2)

Best I can do on the non ethanol is 91. I usually run this. Less pressure buildup in tank.

I can get 110 racing fuel for 7 bucks a gallon, no need though.

mantaguy

iTrader: (5)

That's all I use on both of my toys.

zero13

wish I had Sunoco near me!

TTOP350

iTrader: (8)

When I used to dd mine, I would run 87 until Friday b4 work, then it was 93 for the track and weekend activities. Don't think it helped much if any with a stock motor.

Vanilla Ice

I run 91 at all times and get knock. My car would greatly benefit from 93. The oem timing logic is a bit odd.

NufNuffZ28

iTrader: (10)

I have ran 87-93 and don't see any difference with stock timing and ECM.

thtanner

iTrader: (1)

Are you datalogging?

If so, you will see a difference. I have done that and knock count was higher with 87.

Vanilla Ice

I watch KR 100% of the time with the dash light flashing at me, so I definitely know when I have it.

BUT every car and environment is totally different. Not too many places more taxing than AZ on a car. If I had this car in WA it would be knock free on 92 (maybe even on 89octane 90% of the time.)

NufNuffZ28

iTrader: (10)

I was on my old car, but only ran 93 in it, of course. The current car is an 85 Iroc that I haven't logged and is bone stock. No audible spark knock, and 6 * timing.

Vanilla Ice

Listening for knock is not accurate. And using two different cars introduces a variable rendering it useless for info regarding octane effect.

NufNuffZ28

iTrader: (10)

I was only giving examples of times when, of course, running a higher octane is needed. I had a MSD knock light on the dash in it..... It would only lightly flash before audible pinging started anyway.

BUT, since you obviously are looking an argument. Why don't you log 87 and 93 in the SAME stock car with stock base timing and see what happens?

Vanilla Ice

I already have.

NufNuffZ28

iTrader: (10)

OK. Can you post them up for us?

Vanilla Ice

Nope. You'll have to take my word on it.

brianlibby791

I never really experimented with different octanes (Its only had one fill up in the past 7 years) but i run sunoco 93 and runs like a top. On my dads daily he runs 87, but when he treats it with 93 it runs a little better, as well as an increase in gas mileage. By around 3 mpg's. But all thats ever been in my L98 in sunoco 94 octane (when it was still around) and 93