112 octane, leaded - So Cal

[Embraer]

Petro lock in Lancaster has 112 octane, leaded. $7.50 a gallon. Only caveat is that you either have to trailer your car, or fill up gas containers. I was paying $8.50 for VP racing 100 octane unleaded.

Cheaper than Willow Springs by a margin, and if you're taking your car up there...might be cheaper to fill up on the way.

[John Rogers]

Using 112 octane leaded in a car that was setup and tuned for 100 octane unleaded can cause a drop in performance. I did that many years ago with my high winding 2L six and the engine did not want to rev as quickly, timing seemed to be retarded as witnessed by the flames coming out both sides of the stinger exhaust when I would downshift or let off the gas. I ended up painting the rear bumper after the race weekend.

[Embraer]

Oh, I'm aware. But I did a reset on the ECU's of the car. Idle and revs are much improved after the reflash. a noticeably cooler running engine. exhaust note is deeper...

[Craig T]

Originally Posted by Embraer

Oh, I'm aware. But I did a reset on the ECU's of the car. Idle and revs are much improved after the reflash. a noticeably cooler running engine. exhaust note is deeper...

John is right. Yes, your valves will like the leaded 112, and it will keep things cooler, but without at least 10:5.1 of compression, a more aggressive cam, and timing, you won't see any gain from that octane...and probably a decline. Flashing your ECU isn't going to make good use of 112 octane leaded race fuel. Steve Wong gets good improvements programing for 100 race gas with advanced timing and AFR, but 112 is not for a stock compression and stock fuel delivery engine.

Even my high-strung 3.4L motor doesn't see any performance gain with 110 leaded v.s 100. I buy a 55gl drum of 110 leaded and mix it 2gl/3gl with 91 pump gas. That seems to be about all she can really digest efficiently.

[TerryH]

A turbo or blower could make good use of all the octane available. Otherwise not a great idea.

I raced my Buick Grand National with VP 117 blue. Instant ~150HP with 12lbs of added turbo boost and race chip. Of course the O2 sensor would need to be changed out after being coated with leaded fuel and I dumped exhaust before the cat.

[Embraer]

Originally Posted by Craig T

John is right. Yes, your valves will like the leaded 112, and it will keep things cooler, but without at least 10:5.1 of compression, a more aggressive cam, and timing, you won't see any gain from that octane...and probably a decline. Flashing your ECU isn't going to make good use of 112 octane leaded race fuel. Steve Wong gets good improvements programing for 100 race gas with advanced timing and AFR, but 112 is not for a stock compression and stock fuel delivery engine.

Even my high-strung 3.4L motor doesn't see any performance gain with 110 leaded v.s 100. I buy a 55gl drum of 110 leaded and mix it 2gl/3gl with 91 pump gas. That seems to be about all she can really digest efficiently.

this thing's running 11.5:1 compression. PLUS...the 112 has no ethanol. the VP I was running was an ethanol fuel. so far, I'm happy with the way the car is running versus 100 Street Blaze. ...Plus it's cheaper than the 100 octane.

[Craig T]

Originally Posted by Embraer

this thing's running 11.5:1

11.5:1! Now we're talkin!

[look 171]

My 930 will love it. Plus, it makes the interior of the tail pipe look cleaner.