87 951 VEMS Install
#496
I ran this camshaft some years ago and spent much time doing all sorts of adjustments trying to get it to work and the bottom line is it is not suited at all for a low compression 944 turbo engine. It has too much overlap which causes too much of a compression leak, even under boost. Said differently, it is way too aggressive. Going back to the stock 9R camshaft is the best thing you can do and add an adjustable pulley to find the best cam timing setting for your particular engine.
#497
I ran this camshaft some years ago and spent much time doing all sorts of adjustments trying to get it to work and the bottom line is it is not suited at all for a low compression 944 turbo engine. It has too much overlap which causes too much of a compression leak, even under boost. Said differently, it is way too aggressive. Going back to the stock 9R camshaft is the best thing you can do.
Duration: : 272
Peak timing: : 112
Valve lift: : 12,0
Lift at TDC: : 0,9
Valve timing: : 24/68 - 68/24
I think this may be one problem, but you need to either do a lot of tuning on the street or go to a dyno.
#498
This is originally a NA camshaft profile and as I found out at my own costs it does not work on a turbo engine. Sorry to say but you are wasting your time. Sell it to a NA guy, which is what I did. It is a drop-in replacement in oval dash NA cars.
#499
Ok, this was the cam DBilas recommended for me.
I had the Early NA cam before and i think this is a little better.
The car worked better last year with mafkit and the DBilas cam.
I had the Early NA cam before and i think this is a little better.
The car worked better last year with mafkit and the DBilas cam.
#501
#502
Rennlist Member
* Ported NA head and portmatched intake
* DBilas performance cam
* Specialbuilt and flowprepped k27/8
* O-ringed block
* ARP headstuds
* Rarst rods
* Balance axle delete
* Spec stage 3 clutch
* Lightened flywheel
* Crank, flywheel, pp are balanced
* Rods and pistons are weighted and balanced.
The ignition must be off or it's a major problem with the engine
* DBilas performance cam
* Specialbuilt and flowprepped k27/8
* O-ringed block
* ARP headstuds
* Rarst rods
* Balance axle delete
* Spec stage 3 clutch
* Lightened flywheel
* Crank, flywheel, pp are balanced
* Rods and pistons are weighted and balanced.
The ignition must be off or it's a major problem with the engine
#503
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Join Date: Dec 2012
Location: Scottsdale, AZ
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Hi guys,
Did an engine, turbo, harness, exhaust, flywheel, clutch and a few other mods to my 87 951 DE car. Thought I could just get going with VEMS for startup.
The car has the TTV 60-2 flywheel and stage 3 clutch. 944crazy got the car running with the speed ref sensor swap advice. Had an issue with a bad FI connector which we replaced and it runs on all 4 consistently now.
The car has no ICV
Running deka 80 lb injectors
Tried to start tuning her this week. Installed a separate 02 that reports to an AFR gauge for reference. In addition to the wideband for VEMS
So the car starts and will not maintain idle. Have had to use the throttle cable to adjust keep her steady at about 1200 rpm, and in that area it goes in and out of rich/lean for the first few minutes finally resting pegged lean at 1.83 Lambda. just realizing prob a bad idea to do that given the dependence of vems on TPS?
Problem is, the independent AFR guage is showing rich the entire time at 10.2-10.5 which is accurate based on my sut observation of the new 4" exhaust and of course the simplicity of it.
I know the wideband is ok as we just recalibrated it, TPS is at 12 as opposed to 0 off throttle because of my buddy fiddling with the throttle cable so TPS has to be recalibrated..
What about start idle? I saw 2 logs on here already with different settings for that?
I'll put yesterday's log up and if anyone can help please chime in. thnks
vems log 9/12/19
.
Did an engine, turbo, harness, exhaust, flywheel, clutch and a few other mods to my 87 951 DE car. Thought I could just get going with VEMS for startup.
The car has the TTV 60-2 flywheel and stage 3 clutch. 944crazy got the car running with the speed ref sensor swap advice. Had an issue with a bad FI connector which we replaced and it runs on all 4 consistently now.
The car has no ICV
Running deka 80 lb injectors
Tried to start tuning her this week. Installed a separate 02 that reports to an AFR gauge for reference. In addition to the wideband for VEMS
So the car starts and will not maintain idle. Have had to use the throttle cable to adjust keep her steady at about 1200 rpm, and in that area it goes in and out of rich/lean for the first few minutes finally resting pegged lean at 1.83 Lambda. just realizing prob a bad idea to do that given the dependence of vems on TPS?
Problem is, the independent AFR guage is showing rich the entire time at 10.2-10.5 which is accurate based on my sut observation of the new 4" exhaust and of course the simplicity of it.
I know the wideband is ok as we just recalibrated it, TPS is at 12 as opposed to 0 off throttle because of my buddy fiddling with the throttle cable so TPS has to be recalibrated..
What about start idle? I saw 2 logs on here already with different settings for that?
I'll put yesterday's log up and if anyone can help please chime in. thnks
vems log 9/12/19
.
#504
Three Wheelin'
Hi guys,
Did an engine, turbo, harness, exhaust, flywheel, clutch and a few other mods to my 87 951 DE car. Thought I could just get going with VEMS for startup.
The car has the TTV 60-2 flywheel and stage 3 clutch. 944crazy got the car running with the speed ref sensor swap advice. Had an issue with a bad FI connector which we replaced and it runs on all 4 consistently now.
The car has no ICV
Running deka 80 lb injectors
Tried to start tuning her this week. Installed a separate 02 that reports to an AFR gauge for reference. In addition to the wideband for VEMS
So the car starts and will not maintain idle. Have had to use the throttle cable to adjust keep her steady at about 1200 rpm, and in that area it goes in and out of rich/lean for the first few minutes finally resting pegged lean at 1.83 Lambda. just realizing prob a bad idea to do that given the dependence of vems on TPS?
Problem is, the independent AFR guage is showing rich the entire time at 10.2-10.5 which is accurate based on my sut observation of the new 4" exhaust and of course the simplicity of it.
I know the wideband is ok as we just recalibrated it, TPS is at 12 as opposed to 0 off throttle because of my buddy fiddling with the throttle cable so TPS has to be recalibrated..
What about start idle? I saw 2 logs on here already with different settings for that?
I'll put yesterday's log up and if anyone can help please chime in. thnks
vems log 9/12/19
.
Did an engine, turbo, harness, exhaust, flywheel, clutch and a few other mods to my 87 951 DE car. Thought I could just get going with VEMS for startup.
The car has the TTV 60-2 flywheel and stage 3 clutch. 944crazy got the car running with the speed ref sensor swap advice. Had an issue with a bad FI connector which we replaced and it runs on all 4 consistently now.
The car has no ICV
Running deka 80 lb injectors
Tried to start tuning her this week. Installed a separate 02 that reports to an AFR gauge for reference. In addition to the wideband for VEMS
So the car starts and will not maintain idle. Have had to use the throttle cable to adjust keep her steady at about 1200 rpm, and in that area it goes in and out of rich/lean for the first few minutes finally resting pegged lean at 1.83 Lambda. just realizing prob a bad idea to do that given the dependence of vems on TPS?
Problem is, the independent AFR guage is showing rich the entire time at 10.2-10.5 which is accurate based on my sut observation of the new 4" exhaust and of course the simplicity of it.
I know the wideband is ok as we just recalibrated it, TPS is at 12 as opposed to 0 off throttle because of my buddy fiddling with the throttle cable so TPS has to be recalibrated..
What about start idle? I saw 2 logs on here already with different settings for that?
I'll put yesterday's log up and if anyone can help please chime in. thnks
vems log 9/12/19
.
Make sure your reqfuel settings is correct in the VEMS setup menu according to the instructions. Once that is set and the idle good, you can start tuning the cells of the VE table in the idle area, then autotune, etc. Get a professional to help if you don't know what you are doing!
#505
Rennlist Member
Join Date: Dec 2012
Location: Scottsdale, AZ
Posts: 16
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Chris, until yesterday it wasn't running steady enough to even use the adjustment screw. We should be able to tomorrow though. Reqfuel is where it should be at 5.4 based on calculations from VEMS
I have help from a mechanic (professional) and I intend to get it advanced tuned but gotta get it driving first. Not all mechanics are familiar with VEMS. Tuners some, mechanics not many.
I have help from a mechanic (professional) and I intend to get it advanced tuned but gotta get it driving first. Not all mechanics are familiar with VEMS. Tuners some, mechanics not many.
Last edited by Touringshoe; 09-13-2019 at 11:27 PM. Reason: ww
#506
Three Wheelin'
Chris, until yesterday it wasn't running steady enough to even use the adjustment screw. We should be able to tomorrow though. Reqfuel is where it should be at 5.4 based on calculations from VEMS
I have help from a mechanic (professional) and I intend to get it advanced tuned but gotta get it driving first. Not all mechanics are familiar with VEMS. Tuners some, mechanics not many.
I have help from a mechanic (professional) and I intend to get it advanced tuned but gotta get it driving first. Not all mechanics are familiar with VEMS. Tuners some, mechanics not many.
Exactly where are your VEMS and extra Wideband sensors installed? Are you sure there are no exhaust leaks affecting the readings?
Anyway, I remember the VEMS base map being quite lean, and once I was sure all of my settings were correct (and that I had no vacuum leaks!), I simply adjusted cells in the idle area until it ran smoothly, then did autotune runs. The nice thing about using Lambda instead of AFR is that it is easy to calculate your required VE values---if your idle lambda is 1.10, then you are 10% lean. Simply adjust that cell by 10% and you should be close.
But first get your TPS adjusted properly! The speed/density (MAP-based) fuel model depends on an accurate TPS signal.
#507
Rennlist Member
Hi guys,
Did an engine, turbo, harness, exhaust, flywheel, clutch and a few other mods to my 87 951 DE car. Thought I could just get going with VEMS for startup.
The car has the TTV 60-2 flywheel and stage 3 clutch. 944crazy got the car running with the speed ref sensor swap advice. Had an issue with a bad FI connector which we replaced and it runs on all 4 consistently now.
The car has no ICV
Running deka 80 lb injectors
Tried to start tuning her this week. Installed a separate 02 that reports to an AFR gauge for reference. In addition to the wideband for VEMS
So the car starts and will not maintain idle. Have had to use the throttle cable to adjust keep her steady at about 1200 rpm, and in that area it goes in and out of rich/lean for the first few minutes finally resting pegged lean at 1.83 Lambda. just realizing prob a bad idea to do that given the dependence of vems on TPS?
Problem is, the independent AFR guage is showing rich the entire time at 10.2-10.5 which is accurate based on my sut observation of the new 4" exhaust and of course the simplicity of it.
I know the wideband is ok as we just recalibrated it, TPS is at 12 as opposed to 0 off throttle because of my buddy fiddling with the throttle cable so TPS has to be recalibrated..
What about start idle? I saw 2 logs on here already with different settings for that?
I'll put yesterday's log up and if anyone can help please chime in. thnks
vems log 9/12/19
.
Did an engine, turbo, harness, exhaust, flywheel, clutch and a few other mods to my 87 951 DE car. Thought I could just get going with VEMS for startup.
The car has the TTV 60-2 flywheel and stage 3 clutch. 944crazy got the car running with the speed ref sensor swap advice. Had an issue with a bad FI connector which we replaced and it runs on all 4 consistently now.
The car has no ICV
Running deka 80 lb injectors
Tried to start tuning her this week. Installed a separate 02 that reports to an AFR gauge for reference. In addition to the wideband for VEMS
So the car starts and will not maintain idle. Have had to use the throttle cable to adjust keep her steady at about 1200 rpm, and in that area it goes in and out of rich/lean for the first few minutes finally resting pegged lean at 1.83 Lambda. just realizing prob a bad idea to do that given the dependence of vems on TPS?
Problem is, the independent AFR guage is showing rich the entire time at 10.2-10.5 which is accurate based on my sut observation of the new 4" exhaust and of course the simplicity of it.
I know the wideband is ok as we just recalibrated it, TPS is at 12 as opposed to 0 off throttle because of my buddy fiddling with the throttle cable so TPS has to be recalibrated..
What about start idle? I saw 2 logs on here already with different settings for that?
I'll put yesterday's log up and if anyone can help please chime in. thnks
vems log 9/12/19
.
#508
#510
Sam i noticed that you have raised the ignition quite a bit from basemap at 1200,1600 and 2000rpm below 100kpa.
Why did you do that, do it run cooler with more advance?