I want to run VEMS in place of an LH ECU in a (1988) Porsche 928.
The car is a Quad cam v8 with:
99-1 flywheel
Hall? crank position sensor
Hall cam sensors
knock sensors (2)
twin coil/distributor
batch injection
narrowband O2
MAF sensor
With engine mods has approx 11.5:1 compression ratio
I want to:
replace the old technology LH ECU
learn more about engine management
hopefully re-use as many sensors as possible (most are new).
implement COP, MAP and wideband O2
By changing to VEMS.
My injectors are new 24# and I don't think I have the money for sequential injection (larger injectors?) at the moment so will stick with batch.
I think I'll need these:
1 x LCD4x20
1 x Econoseal 18-Wire
1 x EconoSeal 36-Wire
1 x Wideband O2 sensor
1 x Assembled v3.3 controller
Is there more?
Cheers,
Tim Egan
I recently converted 1986 Porsche 928 S to run on VEMS. It had 100-1 trigger wheel, not 99-1!
Your car however should have more common 60-2 on flywheel, but it's ok, you find it out, when installed! :)
Car has VR sensor on crank and IIRC it was VR sensor on cam also, but you can check it with DVM.
No need for larger injectors when using sequential.
You can do sequential injection and wasted spark ignition even without cam sync.
MAF is totally useless on VEMS install and all other stock sensors work ok.
I suggest you to order EC36 with crimped wires and WB connector also with crimped wires, you definitely want to make a new wiring harness in the engine compartement.
You can check my project here:
http://www.vems.hu/wiki/index.php?page=MembersPage%2FPeepPaadam%2FPorsche
Thanks for the very helpful information.
Please also excuse my stupidity. You're absolutely right, it is a 100-1 trigger wheel. Don't know why I wrote 99-1 (late night).
Wasn't sure how much detail to go into without confusing things too much. The car is an 86 (32v Euro) with the 86 block and bottom end (with some mods), but running 88S4 heads (hence the higher CR) and electronics. So the engine is effectively an 88. I have the sensors, loom and ecu etc for an 88 and was planning on going down that path or MSII till my brother had looked into VEMS (following the thread in Rennlist).
This is a much better alternative and opens up a number of options including COP etc.
I was unsure which way to go with the wires as I was thinking of using tefzel (sp?), but I'm happy to heed the advice of someone who has BTDT.
Thanks again,
Tim