Drag racing questions?????

N2BRK

Well-known member
Dec 31, 2009
2,059
391
83
that's about where I'd expect a max effort tuned stock cp3 to be. But I'm no expert. Look at your log and see what pulse width you were hitting at that pressure to see if you were at 3kus or less.
 

Josh154

Well-known member
Sep 28, 2015
1,220
85
48
Sioux Falls SD
I looked at my log and not seeing anything with a mpa. I'm sure Kory has it dialed in the best he can. I just need to have him bump pw up to 3200.
 

N2BRK

Well-known member
Dec 31, 2009
2,059
391
83
why aren't you hitting full throttle position? Move your floor mat, LOL.
 

N2BRK

Well-known member
Dec 31, 2009
2,059
391
83
I don't log that same one - "D" - mine shows 100%. One other thing that I noticed was the MAF - I don't think mine ever shows that high. Can anyone speak to that? I would have expected about 5 degrees less timing too - might too much MAF bring the timing up too soon? I'm curious and hoping I'm helping and not hurting :)
 
Last edited:

WolfLMM

Making Chips
Nov 21, 2006
4,005
26
48
38
AL
The Maf reading is high... His rail is a little low. It's 1500 psi lower than mine and I'm also running a 3200 pw. IMHO the cp3 is part of the problem, not all certainly but it's weak.
 

WolfLMM

Making Chips
Nov 21, 2006
4,005
26
48
38
AL
Well I don't know, I'm just a key board warrior. But with my 68mm, my maf reading is about 75lbs/min. Maybe Mark or Kory will chime in and explain things to us.
 

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,735
804
113
Texas!!!
I can't say why the MAF is reading high, but that isn't going to make it run bad. MAF just limits fuel if it is too low. The only possible bad thing from a high MAF reading is excessive fuel and smoke. If the truck runs clean, I wouldn't worry about it.

Also, that timing is right in line with what a max effort race tune should be at full fuel. Nothing to worry about there either.
 

Josh154

Well-known member
Sep 28, 2015
1,220
85
48
Sioux Falls SD
I wasn't worried about Korys tune not being right lol. Just need to bump up some more fuel and get the trans tuning on. A guy with the same turbo is doing 12.6 at 107mph same weight as me with the same turbo just 3200pw vs the 3000pw I ran at the track.
 

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,735
804
113
Texas!!!
So whats the deal with maf reading high? What's it supposed to be reading?

Sorry. This post made me think you were worried about the MAF reading in your log. Someone else said something about the timing. I'll keep my comments to myself.
 

N2BRK

Well-known member
Dec 31, 2009
2,059
391
83
I can't say why the MAF is reading high, but that isn't going to make it run bad. MAF just limits fuel if it is too low. The only possible bad thing from a high MAF reading is excessive fuel and smoke. If the truck runs clean, I wouldn't worry about it.

Also, that timing is right in line with what a max effort race tune should be at full fuel. Nothing to worry about there either.

Thanks Josh. The Maf just made me curious, like a leak. The timing is 55% btdc, which will run really clean but I thought too much for a max effort tune in that area - thanks for clearing that up.