Love my VP-101 OXY Unleaded fuel.............

I'm guessing thats the HP101 , 3.77 percent oxygen ?
Man, please tell me more about your results with that?
Thinking of trying it on the Duster's 511.
Any problems with hurting pumps, carbs , lines etc?
If YOUR loving it, i'm thinking of trying it even though 100 octane lost power on the dyno, but thats a dry room, no air flow through a hood scoop etc.
Plugs look good i'm assuming?
Slight jetting change????

I’m not going to say you didn’t see the results you’re claiming........ but I will say this.......

In 30 years of dyno testing, I have never seen a loss like that by running race gas, no matter how low the CR of the engine was.

Unless........ the race fuel was stale.

If you had fresh 93 summer blend, and a sealed 5 gal can of VP c12....... and dynoed the two back to back on a 600-700hp TF headed 10.75:1 BB stroker with a known good carb on top...... fuel curve and timing all sorted out for the 93, then drained the fuel cell and carb........and dumped in the fresh c12.........it’s not going to lose 25hp.

Not here anyway.

The only time I’ve ever seen any kind of significant difference in power from swapping fuels(assuming they have adequate octane for the combo)....... is going from a non-oxygenated fuel to a heavily oxygenated fuel.
Like, from c16 to q16.

My experience has been that losing 25hp going from pump gas to race gas on a build like that would not be a typical result....... at all.

No problems except for, lowet et's, higher mph and tire shredding torque......

Thanks Dom.

Hi Dwayne: Dyno operator predicted the results within a few hp and vp confirmed the results were within their files as well.
Changing timing did offset some of it, but we couldn't make up the losses.
97 Degrees outside temp, 60 percent humidity - lousy hot/humid day.

carb/timing all dialed in etc.

On the race car 511 , switching from regular old 110 race fuel to c12 and adding 2 degrees of timing- car picked up just as Vp predicted , i think we cut .02

Could we be talking about the differences in being in lower mean altitude and in very hot /humid climate compared to there?

Im certainly confused as to why your dyno experience ( which is more than mine ) would be widely different than we see here.
Jessie ( engine builder chebby guy that owns the local speed shop and is at the dyno often ) confirmed that he see's similar inn playing with fuels/engines at the same dyno.

So, i'm really confused on the differences.

For instance, we tried c16 in the race car and it fell on its face .

Very interesting to say the least.

Dom: Im gonna try some this year then and see if it will allow us to stay closer on our number in the heat of the year when water displaces oxygen in our air.

Rusty, it’s certainly possible the weather contributes to the different results.
I’ve never run the dyno in the type of soup you guys are stuffing with down there in the summer.

Also, not all race fuels are created equally........ and I’d never bother trying to run c16 in a 10.75:1 motor.

But frankly I’d be absolutely shocked to lose anything even remotely close to 25hp by swapping from 93 to c12 out of a sealed can(I’d be pretty surprised to see that type of combo even lose 5hp).

That would be my suggestion for the next time you go to the dyno with something that’s at least 10:1 CR.
Pick up a factory sealed 5 gal can of c12....... and retry the test(if you’re so inclined).

I know of several people who have used several different brands of the lower grade race fuels(like VP Red for example), that got less than stellar results. Although I don’t know if those tests were done using fuel from sealed cans of not.

I can tell you this....... a lot of race fuels don’t keep well at all once the seal has been broken....... so if you’re not testing fuel from a container with a freshly opened seal....... imo you’re leaving the door open for misleading results.

Dwayne: Thats very interesting as we get our fuels from a local parts store or Jessie's and they both just pump from the 55 gallon barrels , never gave a thought about getting stale fuel with race fuel.
Might be a valid reason for re-testing.
The c16 from 110 and c12 was on the 13-1 motor.

i know nothing about weather up there in the summer but, here, its bad , huge water per cubic ft of air just kills us on displacing oxygen.
On the other hand, when it starts getting cold and we get a good, dry, north wind for 14-20 hours, that track at 500 ft above sea level will have Da's at 1100 ft below sea level and i can up the jets a good bit.
Down here, for index racing, you have to run at least a tenth under during cold/dry air in order to run your index from late May through September.

i still say burn rate is very important and running the wrong fuel for the compression/cam is a mistake- at least down here.

On the 13:1 motor, what was the original fuel you were running?

He was running 110 , Vp stated we were on the ragged edge on compression /fuel, said we should go to C12 which lined up with what the dyno operator had stated.
Car didn't like anything more than 34 degrees of timing - at all.
We tried it and picked up power and, it would take a little more timing, which also helped.
Well, if a little fuel change is good,,, so, we tried some 16 - car did Not like it .
This engine has pistons about 14 up out of the hole.
Our best runs are on the C12, 35-36 degrees of timing in the heat , 34 when its cooler /dryer.