Trying to tune by VE, but crazy MAF readings make it hard!
10-01-2003, 01:18 AM
#1
Launching!
Thread Starter
Join Date: Sep 2003
Posts: 240
Likes: 0
Received 0 Likes
on
0 Posts
Trying to tune by VE, but crazy MAF readings make it hard! How are you supposed to tune part throttle stuff by the VE table the stinking MAF rading jumps around so much? WOT is the worst (actually anything over about 70%), but part throttle is pretty bouncy too. What's the best way to figure it out? I'm laying it out tonight for my car, but it's proving to be harder than I thought.
10-01-2003, 05:29 AM
#2
11 Second Club
Join Date: Nov 2001
Location: Hanover MD
Posts: 1,645
Likes: 0
Received 0 Likes
on
0 Posts
Re: Trying to tune by VE, but crazy MAF readings make it hard! what scan tool are you using?
i made a pid for efi live that displays on the dash so i can log it, then export it to a spreadsheet to see how the curve wants to go.
i made a pid for efi live that displays on the dash so i can log it, then export it to a spreadsheet to see how the curve wants to go.
10-05-2003, 01:14 PM
#3
Launching!
Thread Starter
Join Date: Sep 2003
Posts: 240
Likes: 0
Received 0 Likes
on
0 Posts
Re: Trying to tune by VE, but crazy MAF readings make it hard! That's what I'm using too, but the MAF is sooooo jumpy at WOT that it makes me wonder if I'm going to be calculating it out accurately?
10-05-2003, 03:46 PM
#4
Teching In
Join Date: Apr 2002
Location: Yuba City/Sacramento Area
Posts: 30
Likes: 0
Received 0 Likes
on
0 Posts
Re: Trying to tune by VE, but crazy MAF readings make it hard! Can anyone post the formula that is being used for calculating the VE table? Also break it down as to what each number is or give an example. I have done some testing and feel confident that VE is being used all the time, I think it is a base multipier for the fueling and would like to start using this table more. But I want to make sure I am using the correct formula so I don't just end up spinning my wheels. NoGo could probably answer this for me.
Also can anyone tell me what injector offset value is being used for the Bosch/SVO 42lb. injectors? I have been told by an injector specialist (business) that these injectors actualy flow about 56lbs. per hour at the 58psi. They also have confirmed that GM injectors are flow rated at 3 bar (45psi) which would mean that the injectors being used in the newer LS-1's actualy flow 31.8lbs per hour at there operating rate of 58psi. They say that they have worked with GM on some stuff so would assume that this info. is correct. My only concern is that by doing the math the flow rate multiplier would be 176%, but I have found that about 143% gets the LT's to 0 for a majority of the time (31.8/56=.567 or 57, now take 100-57=43???) Things maybe off do to an improper injector offset multiplier. Depending on the KPA & RPM cell that I am in, some times throws them to + or - 5% The LT's are very close and I feel if I can properly scale the VE table I will be right on the $.
Also can anyone tell me what injector offset value is being used for the Bosch/SVO 42lb. injectors? I have been told by an injector specialist (business) that these injectors actualy flow about 56lbs. per hour at the 58psi. They also have confirmed that GM injectors are flow rated at 3 bar (45psi) which would mean that the injectors being used in the newer LS-1's actualy flow 31.8lbs per hour at there operating rate of 58psi. They say that they have worked with GM on some stuff so would assume that this info. is correct. My only concern is that by doing the math the flow rate multiplier would be 176%, but I have found that about 143% gets the LT's to 0 for a majority of the time (31.8/56=.567 or 57, now take 100-57=43???) Things maybe off do to an improper injector offset multiplier. Depending on the KPA & RPM cell that I am in, some times throws them to + or - 5% The LT's are very close and I feel if I can properly scale the VE table I will be right on the $.
10-05-2003, 04:59 PM
#5
Launching!
Thread Starter
Join Date: Sep 2003
Posts: 240
Likes: 0
Received 0 Likes
on
0 Posts
Re: Trying to tune by VE, but crazy MAF readings make it hard! I've spoken with a few people about that (we did a Vortech on my friends Z06 and it comes with SVO 42's) and the guys at cmotorsports seem to be the most informed, but who knows? We ended up with our LTFT's on the "$" as they say 
when we used what they told us.
when we used what they told us. 
