Corvette C4, LS1 P1SC Procharger need tune

[legendvette]

hi,
I need someone expert to tune my Procharged Ls1 Corvette C4.
It was running fine with 42lb injecotrs and I replaced the injectors by RC 750cc
and when modify the Injector flow rate to fit with the new injectors its running rough and lean and the AFR is 19 and above
I am not that much expert at the Efilive tunning program

I need a good tunner to modify my tune file and modify the VE & PE to fit to my application

engine : LS1 - 347
cam: 265/271, Lift .558/.563
Injectors: RC 750cc
Transmission: T56
Boost: 7-10psi

the attached file with 42lb injectors

could someone please help me on the subject....


http://www.youtube.com/watch?v=tP8PvVdSBfk&feature=related

[drdarthinvader]

i would start off with injector tuning.
1.injector pulse width mod b3701 the 42lbs green tops require a lot more compensation than the std 19lbs you can increase the whole table by any % till you get the desired level if you map gm manvac on scan you can see what level of vacuum at idle etc. i increased this table by 5% until 80kpa and 14v reached the figure of 0.670.this table will anticipate psychical opening times .same principle with your RC 750cc

2. injector flow rate b4001 use ixl spread sheet enter your parmeters

3.if u want to go further you can adjust injector timing b3702,b3703 which is a delay-offset firing of your injectors. i set both tables to 3.0 which gave me some good results at idle and top end ,its sort of trial and error depending on camshaft profile mine is std.

i haven't done much experimenting with min ipw or default ipw.(input please?)

then start to tune

[legendvette]

thanks for your replay and help

I had no problem with 42lb injectors tuning until 3 of them stop working...

but the real problem is I can not tune the car with the RC 750 injctors

I tried all the excel sheets and some other tuning ideas but non of them work properly...

I do not know where is my fault is, may be somebody has the same problem or
has an Idea to help with...

thanks alot for your co-operation

[drdarthinvader]

check this page out. it might give you some accurate specs on the type of injectors your running check the ohms first there are two types 3 and 12
http://injector-rehab.com/kbse/lag.htm

[legendvette]

check this page out. it might give you some accurate specs on the type of injectors your running check the ohms first there are two types 3 and 12
http://injector-rehab.com/kbse/lag.htm

I am back again

thanks alot for the web site you provided, it's very very helpful and lets me to adjust the injectors timing & voltage correction...

I got some information for RC Engineering:
The injector voltage correction values for the SH4-750 is :

10v 1.36ms
11 1.12
12 0.92
13 0.76
14 0.63
15 0.50
The minimum injection pulse width is about 1.4 ms.

I did the modification on the tune file as the above number and its work perfectly on the Idle

now all what I want to do is to adjust the spark timing with the boost of 10psi and set up the Ve Tables and make it little rich.

[odd boy]

Do you have a wide band? post the file and will make the reuired changes for you.

[legendvette]

thank you odd boy for your replay and interest.

have a look on the dyno sheet before we made the correction on the injectors file and we run it with the stock injector flow rate ,
I'll attached the last modified tune file which I made the correction on and its work great but need some more work on the file to get the max power and the ability to drive it on the street, when I drove it after the correction at the high RPM (full throttle) it run little fine but between 2500-3000 with settle throttle its not. its seemed to be all the time on full throttle :)

have a look may be you can do something before I take it the the dyno test again...

thanks again

[Chuck L.]

Which RC's do you have? The low imp or the hi? If they aere lo, how are you powering them? Are the IFR's calculated at 4 bar?[81.98PPH] I ask because the RC 750's are rated at 3 bars
Also, are you using a return style fpr w/ boost reference?

[odd boy]

Yeah, looks like you had wrong injector values when you went to the dyno at that time. Can you tell me what the AFR is (during PT and WOT)?