87 951 VEMS Install
#631
Burning Brakes
It really is perplexing, but I've messed with every setting and calibration and tried getting support from multiple VEMS gurus (though I must say I have not received much help from the PnP vendor on this) and things they have suggested either don't make a difference or the car won't run.
Like I said before I always had this issue back to day 1 of running VEMS on a totally stock 2.5 NA engine and had to have a wacky VE table to make it run decent. I had a Rogue MAF and tuner before VEMS and I was running 55lb injectors on that without any issue (back in the "i'm going to supercharge it" days).
I think it is a hardware mystery of some kind at the ECU, harness or those green injectors but I've run out of patience to deal with it.
Like I said before I always had this issue back to day 1 of running VEMS on a totally stock 2.5 NA engine and had to have a wacky VE table to make it run decent. I had a Rogue MAF and tuner before VEMS and I was running 55lb injectors on that without any issue (back in the "i'm going to supercharge it" days).
I think it is a hardware mystery of some kind at the ECU, harness or those green injectors but I've run out of patience to deal with it.
#632
Rainman
Rennlist Member
Rennlist Member
Not worth the time. Plus, the stock NA injectors are something like 21#/hr which would be severely limited in E85 performance on this engine, I'd have to redline at 4000rpm probably lol.
This book is closed ! Thank you everyone for input.
This book is closed ! Thank you everyone for input.
#633
Hey just a quick question would anyone have a base tune for a VEMS on a 944 Turbo. I bought the kit off a friend and installed it on my turbo, adding dual port wastegate control for a precession 38mm, and wasted spark. However the kit was originally for an NA so I'm wondering if anyone has a base tune to speed up the process of getting the car running nicely.
#635
Hey just a quick question would anyone have a base tune for a VEMS on a 944 Turbo. I bought the kit off a friend and installed it on my turbo, adding dual port wastegate control for a precession 38mm, and wasted spark. However the kit was originally for an NA so I'm wondering if anyone has a base tune to speed up the process of getting the car running nicely.
You can also look in this thread https://rennlist.com/forums/944-turbo-and-turbo-s-forum/1197074-vems-pnp-kit-starting-issues.html
The following users liked this post:
DLS (01-20-2021)
#637
I'll jump in here now... I'm expecting my Vems to show up from Peep pretty soon. I've got an 86 951, LR Super 65 turbo, 72# injectors, etc etc. Going wasted spark as well. Will be using GSF trigger wheel and hall sensor due to my LR Spec push type clutch and scalloped flywheel. Looking forward to install!
No instructions included obviously, but hoping I can piece it all together. I was also under the impression the kit came with a new TPS although I didn't receive one. My kit also includes the wasted spark and EBC addons.
#638
Three Wheelin'
951 kit does not include TPS since it already has proper one from factory.
Instructions are sent by email, they contain links etc.
Instructions are sent by email, they contain links etc.
Last edited by Raceboy; 01-20-2021 at 05:26 PM.
#639
So I have the car running and driving but I'm having issues with boost control. I have a mac solenoid in place of the stock cycling valve running into a precision 38mm dual port wastegate. I have tested a few different injector channels but I cant get the solenoid to open or close in the output testing mode. I also know that it is not properly controlling the boost as it opens way before the target boost in VEMS. If anyone has any experience with this their input would be greatly appreciated.
#640
Burning Brakes
Mike G.
#642
Burning Brakes
Mike G.
#644
Three Wheelin'
Tuning boost control is not for someone who is not familiar with tuning engine management systems! This is not something to teach with manuals.
If you are not familar how to tune it you should be taking the car to a tuner who can tune boost control.
If you are not familar how to tune it you should be taking the car to a tuner who can tune boost control.