Turbo 4g64, Begi FMU..

[4g64terror]

So I am going to turbo the ole SOHC and thought I would run some ideas by you guys. The only problem I see, really is fuel management. I already have a turbo GSXR-1000 and for fuel management we use a BEGI FMU along with a Dynojet powercommander for fine tuning. The BEGI FMU allows you to adjust the gain with a screw so you can add 0-12psi per pound of boost depending on where you adjust it to as well as base fuel pressure seperately. So with that said, here is a parts list. See what you guys think I should add or subtract:

2g manifold (given to me by a friend)
14b Turbo (same, needs rebuilt)
all stock 2G piping, with BOV (same friend, hes doin a front mount)
Stock 2g sidemount (same friend)
BEGI FMU
2nd GEN downpipe (I might get him to upgrade :) )
miscelaneous oil lines and water lines.
Dynojet Wideband Commander. (and I can use it on the bike too!, 2 for 1)

So how does this look? This is all going on a 1995 SOHC motor. I plan do freshen it up as it smokes a bit. I think most of its valve seals but it has a ton of miles on the car so it couldnt hurt to throw rings in it at least, if not bore it over). Do you guys think I will need an SAFC or some way to fine tune the fuel trim or will that FMU get it close enough? Im talking about with stock injectors here so keep that in mind.

[Stewi]

If your going to take the time to open up the motor, you should just rebuild it with forged internals. If you need to overbore it, that would mean you would need new pistons anyhow, so now your talking about just replacing rods and bearings and having a crank polished. It would only cost you about $800 more to get performance parts, rather than use stockers. This would leave you with a nice platform to build off of in the future.

As far as your questions about the motor cycle tuner and FMU. You need to check the flow rating of the FMU, it might be able to make pressure but not supply the volume of a car. Also with the engine management, does that thing have perameters for a 4 cylinder engine? It needs to be able to control 4 injectors and 4 ignition sequences simulaneously. Also, what signal does it use from the bike to make changes? Is it a mechanical crank/cam triiger? Is it magnetic? Is it a hall effect type sensor? The controller needs input from the motor to make changes and see results, need to make sure its the same type of signals.

[4g64terror]

I am not going to build the motor in a car that I didnt pay shit for. I might just grab another low mileage junkyard motor, throw some new valve seals in it, and run it.This is just a cheap daily driver. Like I said the only reason I am even considering it is because most of the parts will be given to me. The Wideband commander doesnt control any fueling. It is a wideband A/F device. I asked if I should use an SAFC.. The Begi FMU is MADE for cars, not bikes. Ever heard of Bell engineering? Corky Bell? Turbo god? ring a bell? Its his companies FMU. The safc would be used to tune part throttle stuff if needed. I dont see why it would be though consideing off boost it would run like stock and on boost the FMU would handle the fueling.

[seth98esT]

You dont want to use an FMU on the 4g64. It will be very hard to get a good tune with it. If you want to use an AFPR get the 1:1 Aeromotive AFPR.

[4g64terror]

Ok tell me WHY you dont want to use one. Thats the kind of info I am looking for. Is it because the injectors cant handle the FP? Screws up the ECU? What is it?

[4g64terror]

i never did get an answer back on this...WHY is it bad to use an FMU? WHY cant you get a good tune with it? Does the computer try to compensate and pull fuel? anyone??

[seth98esT]

I probably cant give you a technical answer as Im not 100% sure, but all the DSM guys use a 1:1 AFPR, not a 12:1. But I know the 420a guys do use the portfuelers and 12:1 FMUs and they do an ok job but they dont have a MAS, they run off a MAP sensor if that makes a difference.

I myself have the Aeromotive 1:1 AFPR and a Walbro 255 pump and it does a great job. Im not sure if its because our MAS/ECU is expecting a 1:1 boost/fp ratio or what, but EVERY respectable DSM guys are running a 1:1 AFPR or stock.

But just think how they work, base pressure is something like 43psi, with a 12:1 fmu, by the time your running 8psi, the FP has jumped to 139psi, add a descent set of injectors and you will be pushing your injectors too much just with the fuel pressure. Just get rid of the FMU and run the stock FPR unless you go with the 255.

[4g64terror]

the Begi is infinitely adjustable as far as gain rate..not just 12.1...my turbo bike uses the Begi ..im not saying a hi boost application...6 to 8lbs would be perfect.....and what are you using for injectors...im starting to look at that WRX injector swap...those would be able to handle enough pressure id say...thougts on this? describe your exact fuel system and management