Vems installation on my84 928S Euro 16v
08-25-2020, 03:21 PM
#31
Three Wheelin'
MPG will improve with batch fire also, on the config I developed I altered number of injector pulses to have much better control over mixture plus VEMS has closed loop WBO2 which allows to follow target table perfectly.
On 928 it would be just way too much effort for little gain to wire injectors independently if opting to stay with factory harness and using PnP. Other things affect it much more. Going sequential would make sense if one needs to use big injectors (like 600+cc), then it would be worth it as injector pulse would be short enough to make a difference anywhere else than idle. But idle is MUCH better than with LH anyway
On 928 it would be just way too much effort for little gain to wire injectors independently if opting to stay with factory harness and using PnP. Other things affect it much more. Going sequential would make sense if one needs to use big injectors (like 600+cc), then it would be worth it as injector pulse would be short enough to make a difference anywhere else than idle. But idle is MUCH better than with LH anyway
08-25-2020, 03:24 PM
#32
Three Wheelin'
Think its great you have developed this, well done and certainly something I would be looking into on my 88 S4 if MAF or LH started giving any issues. Have you any estimate of the impact on the 32v if you go fully sequential install? guessing its like you state for 944 ie slight improvements in MPG, idle smoother, more responsive, also would it help dealing with increased ethanol (up from 5% to 10%) coming soon?
Yes, ethanol is no problem, can be tuned to whatever content and if using pure E85 you will get more power too
10-07-2020, 04:44 PM
#33
Drifting
Why I bought a standalone ECU for my car.
Before the ecu my car would just bogged down when you quick pressed the gas pedal.
Engine had a rebuild, new crank, cylinders (sleeved), new pistons.
I changed everything on my ignition system, (injectors, plug cables, coils, fuel filter ,fuel pomp, fuel damper, fuel regulators, rotor caps) It improved but still when you did the quick press the car just pause a moment to take off. My MAF had a rebuilt 4 years ago, car had just driven around 10.000 km in 4 years, so I was not directly suspecting the MAF. But to be sure I changed it with a fresh rebuilt one and still the same issue. So, I was finished with the current system, I could not improve anymore on it, so I started looking for alternatives.
Standalone ECU’s
Before I found the Vems PnP solution from Peep, most standalone ECU require that you build a new wire harness and require a wasted spark setup. Mega Squirt is a good solution but for me it was too much work, already saw a setup on another car and I did not feel like going through that process.
I wanted a solution that would not create a lot of work in de engine bay and gave me the possibility to revert to stock. So, when I saw Peep’s solution, I order the PnP kit without wasted spark for the Porsche 928S 16V EURO, it ticked all my boxes for what I wanted.
When I received the kit, the installation was easy. O2 sensor installation and calibration were quickly done, had a bung installed so just needed to install the new O2 sensor that was with the kit. Installation of the TPS sensor needed some work to getting it fitting, but I design a bracket (https://a360.co/2Efw8NW) for it (3d printed part). Calibrated the TPS sensor and started the car.
I also removed the MAF and replaced it with a 3d printed part. (https://a360.co/3iqTwb1) Material for the MAF delete is PA12 and processing was SLS.
The kit comes with a cable set that you can plug directly into the standard wire harness.
Car started right up and ran a smooth idle, after some changes to the fuel table I went for a drive and turned on data logging. When I was finished with the data logging, I started another session whereby I turned on autotune so that the VE table could be adjusted for the changes that where made in the fuel table. I did not change anything on ignition table because I do not have a knock sensor on the car so that needed to be done on a dyno with knock detect device. But the changes where night and day, the car responded very quick on changes made with the gas pedal and my issue with pressing the pedal quick where gone. Only for that reason this was the best upgrade I did on my car.
Because I am not a professional tuner, I took the car to a local tuner here that knows a lot about Vems systems and let him work with the car on the dyno. It took him about 3 hours to setup the car, the car made at the crank 425 nm at 4100 rpm with peak power of 310 hp at 6000 rpm. And 400 nm available at 3500 rpm, the power drop under 400 nm around 5000 rpm and ends with 350 nm at 6000 rpm. The car is much easy to drive because of the quick response and uses less fuel then before.
And yes, the numbers are not that impressive, but the dyno is measuring low as the tuner stated before we started. If I really want to measure my gain, I must go back to the another dyno where I did run with the stock setup and check what the gains are. May that I will do that as a follow up for this post, but for now I see that as a waste of money.
Just want to share this in case someone is thinking about this upgrade on their car.
Lorenzo
Before the ecu my car would just bogged down when you quick pressed the gas pedal.
Engine had a rebuild, new crank, cylinders (sleeved), new pistons.
I changed everything on my ignition system, (injectors, plug cables, coils, fuel filter ,fuel pomp, fuel damper, fuel regulators, rotor caps) It improved but still when you did the quick press the car just pause a moment to take off. My MAF had a rebuilt 4 years ago, car had just driven around 10.000 km in 4 years, so I was not directly suspecting the MAF. But to be sure I changed it with a fresh rebuilt one and still the same issue. So, I was finished with the current system, I could not improve anymore on it, so I started looking for alternatives.
Standalone ECU’s
Before I found the Vems PnP solution from Peep, most standalone ECU require that you build a new wire harness and require a wasted spark setup. Mega Squirt is a good solution but for me it was too much work, already saw a setup on another car and I did not feel like going through that process.
I wanted a solution that would not create a lot of work in de engine bay and gave me the possibility to revert to stock. So, when I saw Peep’s solution, I order the PnP kit without wasted spark for the Porsche 928S 16V EURO, it ticked all my boxes for what I wanted.
When I received the kit, the installation was easy. O2 sensor installation and calibration were quickly done, had a bung installed so just needed to install the new O2 sensor that was with the kit. Installation of the TPS sensor needed some work to getting it fitting, but I design a bracket (https://a360.co/2Efw8NW) for it (3d printed part). Calibrated the TPS sensor and started the car.
I also removed the MAF and replaced it with a 3d printed part. (https://a360.co/3iqTwb1) Material for the MAF delete is PA12 and processing was SLS.
The kit comes with a cable set that you can plug directly into the standard wire harness.
Car started right up and ran a smooth idle, after some changes to the fuel table I went for a drive and turned on data logging. When I was finished with the data logging, I started another session whereby I turned on autotune so that the VE table could be adjusted for the changes that where made in the fuel table. I did not change anything on ignition table because I do not have a knock sensor on the car so that needed to be done on a dyno with knock detect device. But the changes where night and day, the car responded very quick on changes made with the gas pedal and my issue with pressing the pedal quick where gone. Only for that reason this was the best upgrade I did on my car.
Because I am not a professional tuner, I took the car to a local tuner here that knows a lot about Vems systems and let him work with the car on the dyno. It took him about 3 hours to setup the car, the car made at the crank 425 nm at 4100 rpm with peak power of 310 hp at 6000 rpm. And 400 nm available at 3500 rpm, the power drop under 400 nm around 5000 rpm and ends with 350 nm at 6000 rpm. The car is much easy to drive because of the quick response and uses less fuel then before.
And yes, the numbers are not that impressive, but the dyno is measuring low as the tuner stated before we started. If I really want to measure my gain, I must go back to the another dyno where I did run with the stock setup and check what the gains are. May that I will do that as a follow up for this post, but for now I see that as a waste of money.
Just want to share this in case someone is thinking about this upgrade on their car.
Lorenzo
10-07-2020, 06:18 PM
#34
Rennlist Member
Hi Brett,
I guess you are installing a VEMS. I am keen to go this route when ready. I would be interested to see how you progress.
Actually how do we download the 3D print files. I just tried on the MAF delete? And yes the TPS bracket has gone.
I guess you are installing a VEMS. I am keen to go this route when ready. I would be interested to see how you progress.
Actually how do we download the 3D print files. I just tried on the MAF delete? And yes the TPS bracket has gone.
10-07-2020, 10:14 PM
#35
Rennlist Member
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You can easily have whatever ignition system you want even with stock harness, new coils only need sepratae add-on harness. It's just you have to fire COP in pairs (= in wasted spark mode), it is impossible to drive them in full sequential mode without cam sensor (16v engines do not have it and S3 also doesn't). You can also use regular wasted spark coils (such as Bosch 2x2) without any problems.
Also you cannot fire injectors sequentially, it remains batch fire.
Knock sensors are no problem, but obviusly would need shielded cables from sensor to VEMS.
P.S. I have done COP on 16v, I used VAG "shorty" COP (from V5 engines).
Also you cannot fire injectors sequentially, it remains batch fire.
Knock sensors are no problem, but obviusly would need shielded cables from sensor to VEMS.
P.S. I have done COP on 16v, I used VAG "shorty" COP (from V5 engines).
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kingwildh (10-26-2020)
10-28-2020, 04:44 PM
#45
Rennlist Member
Since folks have asked, and I agree that it's not totally clear, here is the website where you can see what's available as a PNP option: https://www.vems.ee/vemspnp/
I had to Google it to find it, as it was not clearly linked (to my eyes) from www.vems.com.
@Raceboy : Perhaps you could update the general site to provide more easily found link to the pnp systems.
Cheers
I had to Google it to find it, as it was not clearly linked (to my eyes) from www.vems.com.
@Raceboy : Perhaps you could update the general site to provide more easily found link to the pnp systems.
Cheers