L3YMS

iTrader: (2)

..

john banks

I may or may not be clever, but I invented the MAFSIM and Andrew Carr provided the hardware and finishing touches.

A voltage based MAP sensor with a linear MAF curve and some correction in the tuning would be great except for two problems:

1. MAF would have to follow MAP * RPM.
2. On throttle transients you get a lean spot that can't be entirely covered with acceleration enrichment settings in the Power FC. As the throttle opens, the MAF sensor sees an inlet manifold filling spike which gives prior enrichment in advance of the slug of air about to be drawn through the inlet valves.

Solve the above two and you have... MAFSIM.

JdcTypeR

iTrader: (19)

John are the mafsims still available and are they reliable?
Cheers
James

john banks

James, not sure how reliable they were or whether they are still available as I moved on, but at the time they fulfilled a need when the available ECU options were more limited or expensive. If you could run speed density in the OEM ECU that would probably be better these days I think.

L3YMS, I've not looked at the SAFC2, but if it can produce a simulated MAF output based on RPM and MAP then it could, but you would want someone else to have tried it on a Subaru to be sure it doesn't go lean on acceleration enrichment as that was the biggest headache on MAFSIM. Even if it did work, it doesn't seem ideal (like it wasn't really with the MAFSIM) to use two programmable devices to map one engine in two layers IYSWIM?

I had a quick look for an SAFC2 manual in English, but can't readily find one, except for other people looking for one...

john banks

http://www.scribd.com/doc/19580150/A...Manual-SAFC-2-

I found the above, and it doesn't look like the throttle compensation will be suitable to fill in the hole you'd get that would make it go lean on a throttle transient, more a fixed adjustment for various throttle angles with interpolation. It could modify a pressure signal, but doesn't seem to be designed to compensate heavily by effectively multiplying the "airflow" input signal by RPM, more it is designed to trim it by RPM and the range of adjustment may be too small.

Too many questions unless you know someone who has done it successfully.

stedee

iTrader: (4)

i dont think that many were made , i know andy f used one for a bit, not sure on this but i think there may have been some reliability issues but it was to be expected, they were prototypes after all. andy carr may still have one, not sure. things have moved on tbh

john banks

The modern result of this project for me was to write conversions of the Evo IX and R35OEM ECUs to run speed density. Both were very smooth and effective as it is relatively easy to code this stuff compared to adding a bunch of electronics. The Evo needed a lot more acceleration enrichment, the GTR didn't.

Ian

iTrader: (10)

i have got a apexi power fc on my classic and am running a newage maff sensor