87 951 VEMS Install
#421
Pro
I hope it's okay to hijack this VEMS thread - it seems to be best single source I've found.
Four questions:
1. Is there a comprehensive guide out there for tuning? I have been searching the forums and web and only find bits and pieces.
2. The tach in my dash works perfectly except that it seems to 'slip' above 5000 rpm under boost and load. The engine continues to rev but the needle floats at 5000. VEMS seems to report correct rpm though.
3. Boost gauge in dash is erratic (bouncing around) during steady driving, but reports properly under boost - is this normal?
4. Cold idle needs adjustment - is there a guide on this? Idle is low (800 rpm and lower) on cold start even after adjusting screw in throttle. I still need to double check the ISV functionality, but starting was very difficult today at 8C.
Thanks guys!
Four questions:
1. Is there a comprehensive guide out there for tuning? I have been searching the forums and web and only find bits and pieces.
2. The tach in my dash works perfectly except that it seems to 'slip' above 5000 rpm under boost and load. The engine continues to rev but the needle floats at 5000. VEMS seems to report correct rpm though.
3. Boost gauge in dash is erratic (bouncing around) during steady driving, but reports properly under boost - is this normal?
4. Cold idle needs adjustment - is there a guide on this? Idle is low (800 rpm and lower) on cold start even after adjusting screw in throttle. I still need to double check the ISV functionality, but starting was very difficult today at 8C.
Thanks guys!
#422
Three Wheelin'
1. Is there a comprehensive guide out there for tuning? I have been searching the forums and web and only find bits and pieces.
I recommend the HP Academy courses ( www.hpacademy.com ) if you have time, they are excellent. Also search Amazon for "Greg Banish," he has written some excellent books on tuning.
2. The tach in my dash works perfectly except that it seems to 'slip' above 5000 rpm under boost and load. The engine continues to rev but the needle floats at 5000. VEMS seems to report correct rpm though.
Was your tach working properly before? That sounds more like a tach or wiring issue if VEMS is reading it correctly.
3. Boost gauge in dash is erratic (bouncing around) during steady driving, but reports properly under boost - is this normal?
My factory boost gauge did the same thing after installing VEMS---it now reads gauge pressure instead of absolute pressure. I'm OK with this so have not looked into it.
4. Cold idle needs adjustment - is there a guide on this? Idle is low (800 rpm and lower) on cold start even after adjusting screw in throttle. I still need to double check the ISV functionality, but starting was very difficult today at 8C.
You will have to experiment with your cold cranking enrichment table in VEMS. I still haven't dialed in the ICV on my car, the ICV works well but my idle is high (~1,100 RPM, even with base idle/screw adjustment ~800.RPM). I have been living with it until I have more time to play around with it, too many other car projects! But my cruise and high-load tune are dialed in nicely.
I recommend the HP Academy courses ( www.hpacademy.com ) if you have time, they are excellent. Also search Amazon for "Greg Banish," he has written some excellent books on tuning.
2. The tach in my dash works perfectly except that it seems to 'slip' above 5000 rpm under boost and load. The engine continues to rev but the needle floats at 5000. VEMS seems to report correct rpm though.
Was your tach working properly before? That sounds more like a tach or wiring issue if VEMS is reading it correctly.
3. Boost gauge in dash is erratic (bouncing around) during steady driving, but reports properly under boost - is this normal?
My factory boost gauge did the same thing after installing VEMS---it now reads gauge pressure instead of absolute pressure. I'm OK with this so have not looked into it.
4. Cold idle needs adjustment - is there a guide on this? Idle is low (800 rpm and lower) on cold start even after adjusting screw in throttle. I still need to double check the ISV functionality, but starting was very difficult today at 8C.
You will have to experiment with your cold cranking enrichment table in VEMS. I still haven't dialed in the ICV on my car, the ICV works well but my idle is high (~1,100 RPM, even with base idle/screw adjustment ~800.RPM). I have been living with it until I have more time to play around with it, too many other car projects! But my cruise and high-load tune are dialed in nicely.
#423
Rainman
Rennlist Member
Rennlist Member
if you have tuning questions specific to VEMS (functional) then ask in here and those of us with the ECU can chime in.
this is a good thread for posterity, probably should save the page to the vems wiki lol
this is a good thread for posterity, probably should save the page to the vems wiki lol
#424
Instructor
Join Date: Feb 2006
Location: Cedar Rapids, IA
Posts: 118
Likes: 0
Received 0 Likes
on
0 Posts
Thanks
_Jeff
#426
Rennlist Member
Could someone who purchase their VEMS with wasted spark system, post up the part number of the wasted spark coil pack? Also where each spark plug goes on the coil. May have found the solution to my issue. Thanks in advance.
#428
#429
Rennlist Member
Thanks! I purchased the same part, just wanted to be sure. Would you happen to know the part number of your spark plug wires? And also, which spark plug wire number goes to which poles on the coil pack. Thanks again.
The following users liked this post:
shortyboy (06-24-2019)
#431
Burning Brakes
#433
Burning Brakes
The following users liked this post:
Velozipedia (09-15-2019)
#434
Rennlist Member
Anyone know the part number of the spark plug wires included in the kit? Picked up a set of audi 5000 that would fit the coil side but would like the beru plug boots on the head side instead of the metal sleeves on the audi set.
The following users liked this post:
H.F.B. (06-24-2019)