Heffner Tune and Pully Fuel Recommendation?


H

Hydra GT

GT Owner
Mark II Lifetime
Oct 18, 2008
137
Delray Beach, FL
I had the Heffner Pulley and Tune done at their shop last year. They set it for 93 Octane. I guess there is a 91, 93 and 100 tune.

What fuel do I use for their 100 tune here in South Florida?

Will there be any benefit to using the higher octane for a mile run, etc?

Any real horsepower gains or should i worry about detonating the engine? or should i just stick with the 93 tune?

I also have the cat delete pipes that i am thinking of installing. Is that worth any performance gains (less heat soak) as well?
 
I have an opinion however I would encourage you to chat with Jason Heffner and ask his feelings.

Takes care

Shadowman
 
Ok Thanks Shadowman. Would you care to PM me Your opinion? I will give Jason a call. I just hate to bother him during his hectic days.
 
Last edited:
I'm a little confused, so I must be missing something. If you have 3 tune files, 91, 93 and 100 octane, and you "run 100 octane" gas, as you said in your post, wouldn't you simply switch the tune to the 100 tune? Do you remember, when you fill up the tank with the 100 octane gas, was the tank pretty empty? if not, I wouldn't switch to 100 tune because (using simple math) if you had half tank of 93 gas and filled up the remaining tank with 100 gas, you have ~96 fixed-octane in your car, as such, to be safe you might want to stick with the 93 tune.

Assuming 93 octane is widely available in Florida, unlike here in California all we get is 91 (well, very far and few between some stations have 96 and 100), why wouldn't you get from Jason the 93, 96 and 100 tunes, simply for the reason that you will in occasion have to "fix" different gas?

Ed
 
good point GTED. I have only run 93 in my car. I will have to give Jason a call and see what his thoughts are.
 
Hydra GT said:
Ok Thanks Shadowman. Would you care to PM me Your opinion? I will give Jason a call. I just hate to bother him during his hectic days.
Click to expand...

You are welcome

If my tune I would answer however out of respect for Jason this question belongs with him.

Now simply because one has a 91, 93, 100 octane tune does not mean that simply changing the tune and then adding higher octane fuel = best tune for all conditions.

The gals respond and operate best if how she is being exercised is a component of the tune; for example an aggressive street tune is one thing however they need IMO something different if an aggressive road course is where she is exercised and the same holds true IMO for the mile.

Takes care

Shadowman
 
Excellent point about the road course tune. I want it to play it on the safe side for the road courses and mile tunes. I am sure that mid August at Sebring where you have a 95 degree day makes it important to have the right octane and tune simultaneously.
 
A simple rule of thumb is if you have a calibration written for a certain octane fuel only use that tune with that specific octane or higher fuel.
 
AND, talk to the tuner who designed and installed the tune in your car.

These are pretty rudimentary questions, and Jason I am sure can answer all your questions on this topic.
 
indy gt said:
and, talk to the tuner who designed and installed the tune in your car.

These are pretty rudimentary questions, and jason i am sure can answer all your questions on this topic.
Click to expand...

100%
 
Sorry I didn't respond to this sooner. I had a nasty stomach virus yesterday which rendered me out of commission.

If you run 100 octane fuel with the 100 octane tune you should expect to pick up another 30 horsepower or so. Since this tune is designed for this fuel you should have no concerns of detonating the engine. If you are going to do a one mile run, the 100 octane tune is likely worth 5 mph or so.

Lastly, please don't ever hesitate to call. I am always happy to help.
 
You must log in or register to reply here.

Top Bottom