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-   -   87 951 VEMS Install (https://rennlist.com/forums/944-turbo-and-turbo-s-forum/984075-87-951-vems-install.html)

Porvair 05-09-2018 10:05 PM

Not yet Peep. I can only work on the car on the weekend so will take a look then.

Thanks
Sean

SamGrant951 06-16-2018 10:07 AM

https://cimg3.ibsrv.net/gimg/rennlis...6ad29bfdb6.jpg
Anyone have the round gauge up and running? No matter if I try and connect to my computer COM port or the VEMS ECU it will not power on / show up in Vemstune. The instructions are lacking IMHO, I see these wires which one is red/white with a fuse so Im guessing it wants 12v and the other blue wire I originally assumed would be ground except the printout shows rpm input. I don't need any of the extra wires for WB02/input as I am just trying to stream the data from the ECU when the laptop isn't plugged in.

SamGrant951 06-17-2018 11:58 PM

Also is anyone else having to adjust fuel req quite a bit? Seems like once I start the car / comes out of cold start mode - car happy and fuel req good / then after a long drive and the car is hot - the target values are way different (lambda). Are you just supposed to shoot for a happy medium or tune it based on hot or can it be weather/temp dependent? My car does not seem happy timing wise (haven't touched it - on a base map sent with the unit) - I have contacted a local well known tuner who hopefully can dial it in, I think the fuel map is OK as we have messed with it quite a bit but its so lazy coming into boost the timing is just obviously way off - its nothing like the car used to be. I expected to have to dial this all in so not complaining - just curious what others are seeing that have been messing with it themselves.

odonnell 06-18-2018 12:36 AM

You probably need to tune the air temp curve. Heat soak at the air temp sensor can cause weird running, so there's a curve to compensate.

Raceboy 06-18-2018 02:48 PM

Sam, you need 12v for the gauge and also RS232 connected but with twisted polarity, so that Rx of VEMS is connected to Tx of gauge and vice versa.

Porvair 07-06-2018 03:46 PM

So I've had VEMS up and running for a couple of months now on a mostly stock 951s (38mm Tial and manual boost control limited to 15 or 16lb) and all seems fine after working out a few minor quirks. Good track day last week but I was stupid not to refresh the sparkplugs as the ignition started to breakup at 5500 up, but that is now resolved with fresh plugs.

I had I've run the autotune in the VEMS software, but I am wondering whether it is worthwhile having a dyno tune so as to maximize efficiency/power. I am more of wrench guy than a software guy and given the investment so far I want to ensure that I am getting all I can out of the VEMS (and also realizing my own limitations and lack of experience with the software).

Have others taken this route? I'm no aware of any VEMS-specific tuners in my are (Long Island NY) but there are a lot of dyno tuners with good reputations in the area. Would the VEMS software be easy enough for an experienced non-VEMS tuner to pick up and easily mange?

Thanks for any thoughts or advice.

944crazy 07-06-2018 09:15 PM


Originally Posted by Porvair (Post 15125257)
So I've had VEMS up and running for a couple of months now on a mostly stock 951s (38mm Tial and manual boost control limited to 15 or 16lb) and all seems fine after working out a few minor quirks. Good track day last week but I was stupid not to refresh the sparkplugs as the ignition started to breakup at 5500 up, but that is now resolved with fresh plugs.

I had I've run the autotune in the VEMS software, but I am wondering whether it is worthwhile having a dyno tune so as to maximize efficiency/power. I am more of wrench guy than a software guy and given the investment so far I want to ensure that I am getting all I can out of the VEMS (and also realizing my own limitations and lack of experience with the software).

Have others taken this route? I'm no aware of any VEMS-specific tuners in my are (Long Island NY) but there are a lot of dyno tuners with good reputations in the area. Would the VEMS software be easy enough for an experienced non-VEMS tuner to pick up and easily mange?

Thanks for any thoughts or advice.

You can definitely benefit from a proper tune. The base ignition map is very conservative. If all you are getting tweaked are the fueling and ignition maps, then yes any good tuner can do that.

SamGrant951 07-06-2018 11:18 PM

Im scheduled to have my car tuned on a dyno July 26th by a place up north of Chicago - seems like they tune about anything and are familiar with most standalone systems. $725 flat rate.

Porvair 07-08-2018 06:39 AM

Thanks 944crazy and Sam. I will speak to some of the local shops and see if I can find someone who is comfortable with VEMS. Not surprisingly, most of the shops cater to VW, Subies, Nissan, etc and nome mention VEMS on their websites, but I imagine that someone familiar with standalones could work with it.

Sam - please let us know your results. If only you could dial in the low-end grunt of your GTI (my DD is a '16 GTI with performance package).

Sean

blade7 07-08-2018 12:18 PM


Originally Posted by SamGrant951 (Post 15125972)
Im scheduled to have my car tuned on a dyno July 26th by a place up north of Chicago - seems like they tune about anything and are familiar with most standalone systems. $725 flat rate.

$725 to tweek Peeps map, they might do it in a hour or two...

SamGrant951 07-08-2018 05:01 PM

Well my car doesnt seem real happy on Peeps basemap. Driveable sure but its fouling plugs and seems to miss a bit, and lazy as heck coming on boost. Thats fine - its a basemap and I expected to have to tune it / dial it in. I prefer to have someone who knows what they are doing do it and be done with it.

Yes I didnt have much luck finding anyone in town that would mess with the VEMS, the big go-to tuner guy in town said No - guess he just wants to work on what he is familiar with. Ill be sure to report back.

Yes love that GTI from down low :) Great DD!

Wojo7 07-08-2018 05:16 PM


Originally Posted by Porvair (Post 15127933)
Thanks 944crazy and Sam. I will speak to some of the local shops and see if I can find someone who is comfortable with VEMS. Not surprisingly, most of the shops cater to VW, Subies, Nissan, etc and nome mention VEMS on their websites, but I imagine that someone familiar with standalones could work with it.

Sam - please let us know your results. If only you could dial in the low-end grunt of your GTI (my DD is a '16 GTI with performance package).

Sean

I am also searching for a reputable shop on the island, I don’t think I’m going to install the VEMS I have until I find one. If I make any progress I’ll be sure to post.

Droops83 07-08-2018 09:44 PM


Originally Posted by SamGrant951 (Post 15128679)
Well my car doesnt seem real happy on Peeps basemap. Driveable sure but its fouling plugs and seems to miss a bit, and lazy as heck coming on boost. Thats fine - its a basemap and I expected to have to tune it / dial it in. I prefer to have someone who knows what they are doing do it and be done with it.

Yes I didnt have much luck finding anyone in town that would mess with the VEMS, the big go-to tuner guy in town said No - guess he just wants to work on what he is familiar with. Ill be sure to report back.

Yes love that GTI from down low :) Great DD!

I guess I should mention that it is entirely possible that you have underlying issues that have nothing to do with the VEMS system or its base map (for example, is the Wideband O2 sensor properly calibrated? Vacuum/boost leaks? Exhaust leaks? Fuel system issues?)-----but let's assume that you do not. The VEMS auto-tune feature is great for dialing in idle/cruising/light load stuff in terms of VE/AFR (save the ignition timing curve for the dyno). I have done a progressive sequence of manual tuning of the base VE map to get into the ballpark, followed by some lengthy autotune drives (datalogging the entire time), then going back and manually fine-tuning the VE table after studying the log. Rinse and repeat several times. I first did this with the bone-stock engine/turbo/fuel system, then with upgraded turbo/exhaust and larger injectors/fuel pump/3 bar fuel pressure regulator (after changing the base/reqfuel setting), and the engine runs better than it ever has with crisp throttle response and minimal turbo lag.

It's the part-throttle/transitional street driving stuff that is most time-consuming to set up, so if you get much of that out of the way, the majority of the dyno session can be spent optimizing a safe ignition timing curve and focusing on high load/full boost maps.

odonnell 07-09-2018 09:07 PM

Tuning a speed density ECU is virtually the same between all systems. It's a simple load/RPM map.

Also when you change the ignition map, you will need to re-visit the VE table as there will surely be fueling requirement changes to meet target.

gpr8er 07-14-2018 10:35 PM

Finally got around to installing the VEMS. Car starts and runs...barely. It's off the chart lean right now. I have attempted to pair the VEMS with my laptop but it's requesting a pairing code. Wondering if you guys have an answer? TIA


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