Old 5.7 300C driver here (3 years) with new Diablo U7135.
My car is stock, although I just replaced the thermostat with 180c unit.
I am running 91 US octane premium and the 93 CAI tune. I spoke with Diablo tech support, as my unit only shipped with 93 canned tunes. They explained this was due to lack of storage for export vehicles. They also explained the 91 and 93 canned tunes are IDENTICAL with exception of the WOT spark timing. This made me feel better about the rest of the Map's below WOT so decided to tweak the 93 tune with logging to see what I could obtain.
My first run with only -1deg at 4000-4800 rpm suffered knock bad!!! See results #1.
I then reduced the spark by 3 and added 3% fuel. Not much better. See result #2.
Then I spent a good few hours searching the forums here and picked up the following key points:
- Set cooling fans for 185/195/195 with the 180 thermostat (stevesrt8). Check done.
- Knock most likely due to lean mixtures, often 3-15% more fuel required (NeverToFast). Check done.
- Canned tunes run LEAN!!!
- Ideal spark timing is around 21-24 degrees.
So, take a look at my third tune, knock is under control, I think my next tweak should be:
Fuel: +6.5, +8.0, +10.0
Spark: -1.0, -3.0, -3.0
Do you think I am on the right track? I know, get a CMR tune... I'd like to have a go first!
BTW, this 3rd tune with firmer shifts is awesome, I have never felt a kick in the pants like this in 3 years!!! Pulls hard and strong!!!!
Thanks in advance.