They probably think that we use the sct "base" (junk) value files with no changes, and that's where they start from. Which we dont, btw. I'm not saying anything about the car that's negative. I'm saying it's possible that bad gas, a vacuum leak, temperatures (IAT or ECT) there's alot of factors. The car needs to be datalogged and ran in certain conditions in order to get correct (fair) information. The fact that you said it had to have anything more than a degree or two of timing removed tells me one of a few things is present.... horrible gas, misinformation, vacuum leak (lean condition). I send out the same timing table that you received to many others with no problems.

Ethanol content is a huge factor in things anymore, too. The stoichiometric air fuel ratio has to be richened (to roughly 14.4). Because of your location your file has still been sent with a normal 14.64 stoich point and 12.80 commanded ratio. I would say that the best plan of attack would have been to enrichen.

 

I'm going to bump this for another data point out of California. I'm running a Brenspeed 91 octane tune and also have had consistent detonation in the 4,000+ rpm range, mainly under WOT conditions, but also under part throttle conditions under the right load conditions (going uphill, or in 3rd and 4th gear on the highway).

I just emailed them to let them adjust the tune and I'll report back with what works.

In the interim, I've so far pulled 4 degrees of timing out in the 4-8k range. It's helped a lot, but I'm still getting detonation above 5k at WOT. I may try another 2 degrees (total of 6 degrees removed), or add fuel and see what happens.

Bottom line is that California fuel sucks. I don't know if it is the ethanol content (6-10%) or what, but the tuners definitely need to take California purchasers into account.

And in no way is this a strike against Brenspeed--I ran his 93 octane tune in Maryland (and elsewhere on the East coast) and never had an issue.

 

Same exact issue here in Nevada. I didn't have to pull nearly as much timing though. I guess the quality of fuel plays a HUGE part with tuning.

They were able to troubleshoot it for me in just a few emails and the problem was dialed out.

I really wish I was still in Chicago. 93 was plentiful and even 100 and 105.

 

So how much timing did you have to pull out and at what RPM range?

 

Another update--I left the timing with 4 degrees pulled out from 4k-8k and added 4% fuel at WOT. Detonation gone and it actually pulls harder in the lower rpms as a bonus!

 

1 degree in the 2000-4000 range and 2 degrees in the 4000-8000 range. I think its really based on the fuel in your area too.

That is what fixed it for me. Import slaya had the same basic tune but had to tweek it a lot more based on the fuel that was available to him.

 

I found this thread with a google search and joined the forum.

I ordered 3 Tillman tunes:
1) 93 all out
2) 93 performance
3) 87-89 performance

On WOT I heard a clatter/rattle/pinging that I didn't have with the stock tune; it was worst with 1) and least with 3) but still there (even with 93 octane Shell gasoline).

First I called Chris R and he said he thought it was a cam phazer issue. Since my car is under warranty and it doesn't do it with the stock tune that would mean nothing could be done.

Then I read this thread and I adjusted my options. I retarded timing 1 degree on 2-4k, 2 degrees on 4-8k and then I increased the fuel WOT richness 2%. This made it better but it was still there. Since then I have switched to 89 octane (to save money).

Then, this last weekend I cleaned the MAF, throttle body, Green filter and replaced the fuel filter on a lark (I would have thought none of these would have needed to be done since my ride is a 2008 Bullitt with less than 15k miles on it).
The interesting thing is that the problem went away. On my test drive, no rattle or clatter. Out of curiousity I changed the options to where I am only retarding the timing 1 degree on 4-8k. I took out the WOT fuel richness and then I went out and got on it. No clatter.

The real test will be when I run this tank of 89 octane out; I am going to fill up with 93 octane and I am going to reload the 93 performance tune with maybe only a degree retarded on in the 4-8k range. I will post my results.

Is it possible that it was the fuel filter????

 

Absolutely, or bad gas. Or MAF signal being "dirty" will completely change the vehicles performance. I'll bet you fill up with a good brand name 93 octane, make sure you run a full tank of 93 octane through, and then load the tune for 93 in after the SECOND fill up. I'll bet it's spot on with no adjustments.

Our tune files are enrichened for ethanol content and conservative on timing. If there's pinging it's USUALLY elsewhere. Occasionally you'll have a car that doesn't tolerate timing, but there's always a reason for it, hidden somewhere mechanically.

Chris

 

I played with the vehicle and the adjust options, out of curiosity, while I am waiting to finish up the 89 octane tank.
My opinions are subjective (no dyno) but the car just runs better (stronger) with the timing retarded 1 degree from 2-4k and 2 degrees from 4-8k and with the fuel richened by 2%.

Is there any harm to running the richer wot fuel??

Thanks very much,
Ron

 

Ron,

Is this on our tune file? Someone elses? You need an air fuel ratio gauge if you're going to adjust WOT fueling. 2% isn't really a huge deal. It's the difference between 13.0 and 12.8, or 12.8 and 12.6... not really that big a deal.

 

Yes, on your 87-89 performance tune.
This weekend I took the Bullitt on a road trip and put 3 tanks of 93 octane Shell through it. After the 2nd tank I switched to the 93 performance tune which I had really liked. I left the options adjusted the same as on the 87-89 tune (-1 degrees 2-4k, -2 degrees 4-8k and the 2% richer wot). Car ran really well; also under wot.
It is always possible it was a rattle and not pinging...but the adjust options seemed to cure it in both tunes.

I really like the performance tune...very responsive but not too agressive as the Bullitt is my daily driver.

I guess what I really need to do is put the car on a dyno with a wideband sensor? I live in the boonies so I need to drive up to San Antonio or Austin during the week when I have time to get it done..

Thanks very much for the reply,
Ron

 

Don’t be a fool and chase that gremlin spending thousands of dollars when it’s just a dirty sensor clean your AC T sensor and your MAF sensor the pain will be gone

 

if he's still chasing that gremlin after 10 years . . . well . . . that was one heckuva long wild gremlin chase!

 

Clean your mass airflow sensor and your ACT sensor that fixed pinging issue for me save your money, cost me nine bucks in spray