M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Swaps, Turbos, Buildups => Topic started by: kpjo4 on May 06, 2013, 10:47:22 PM

Title: help turbo fmu setup
Post by: kpjo4 on May 06, 2013, 10:47:22 PM
Hello fellow m42 enthusiasts, I have turbocharged couple of Hondas with the use of a FMU 12:1.
My question is since Hondas use MAP sensors rather than MAF sensors how would I go by doing so? With the MAP sensor you would have to use check valves (missing link).

I so far will be fabricating my own turbo manifold, Intercooler piping, and will use the warlboro255lph high pressure fuel pump on stock injectors, is this even possible? Sorry for my noob question since this is my first time on putting together a turbo setup for a MAF motor.

p.s. this is my 2nd BMW my first being a e92 335i, and I love the Bavarian auto world <3 :]

thanks in advanced fellas
Title: Re: help turbo fmu setup
Post by: riche on May 11, 2013, 04:31:59 PM
Hi, my experience on supercharging not turboing would suggest fuel pump is OK for standard injectors( I've used one now after standard one failed) and doing the job, the test runs done with my setup but use a rising rate solution rather than fixed, a bit of a fiddle getting starting psi and then rate right but it works well when done. One thing you'll notice coming from Honda world is the injectors flow is much lower on stock. Can't think of reason of what you are doing not working but perhaps someone much more knowledgeable than me will point you in the right direction if it is a bit stray.
Title: Re: help turbo fmu setup
Post by: wazzu70 on May 11, 2013, 09:36:09 PM
Nothing should be different on a car that uses an AFM/MAF over a MAP sensor as the FMU is not electronic. The FMU references manifold pressure/vacuum only which is independant of airflow metering device.

Not sure what ratio is best to use. I know many years ago the BEGI unit was the one to use.

Keep in mind you also need a chip to reduce the timing.
Title: Re: help turbo fmu setup
Post by: kpjo4 on June 23, 2013, 02:17:04 AM
I chose to get a rrfpr and some f150 injectors, same one as mustang injectors. T25 sr20det turbo, runs fine but haven't check AFRs, why should I retard the timing?
Why retard the timing? Wouldn't a more advance timing make a cleaner burn and make it hotter for the turbine to spool faster?
Title: Re: help turbo fmu setup
Post by: wazzu70 on June 24, 2013, 11:14:15 AM
Sounds like you need to read a bit to get an idea what you are doing.

Timing is retarded in the upper range due to the increased cylinder pressures. Leaving timing where it would be on an atmospheric engine will just cause detonation.
Title: Re: help turbo fmu setup
Post by: dmnracing on June 25, 2013, 08:46:19 PM
Nothing should be different on a car that uses an AFM/MAF over a MAP sensor as the FMU is not electronic. The FMU references manifold pressure/vacuum only which is independant of airflow metering device.

Not sure what ratio is best to use. I know many years ago the BEGI unit was the one to use.

Keep in mind you also need a chip to reduce the timing.
[/quote
What chip would u have in mind? Have not uncovered a chip to retard the timing in all my research for a turbo application ?
Title: Re: help turbo fmu setup
Post by: kpjo4 on June 27, 2013, 06:45:57 AM
Sounds like you need to read a bit to get an idea what you are doing.

Timing is retarded in the upper range due to the increased cylinder pressures. Leaving timing where it would be on an atmospheric engine will just cause detonation.




Running the motor hard for some time now and not a single knock yet
Title: Re: help turbo fmu setup
Post by: wazzu70 on June 27, 2013, 11:14:42 AM
Well, if you arent making much more power you are probably OK with stock timing. Keep in mind you cannot hear a lot of detonation without an amplifier! If you are going by your ears there is a lot you could be missing! Stock cast pistons also cannot handle the cylinder temps and detonation a proper set of forged pistons can. Just some things to keep in mind!

As for chips, I don't know of any off the shelf units. I went with a standalone so I did not investigate chip options.