Fmu

[david-b]

Could questions on a FMU. More specifically to Silver.

I know there's a couple different kinds, like ratios. What does what and works for what?

And can you have one on without a turbo or anything else and still have the car work properly?

Do you need a AFPR also?

[SilvrEclipse]

Ok, first off DO NOT buy a FMU. I used one when first turboed the 420a and it really doesn't work that well. It leaked air pressure and made me go lean. You have to run a 12:1 ratio on stock injectors which puts fuel pressure over 100psi at about 7psi of boost. Not that good IMO. You can run the stock FPR with this setup also.

Go ahead and spend a little more money and get the SFMU. Its a little more expensive but works a hell of alot better. Also I would upgrade the injectors while your at it. With the SFMU this acts as a FPR also so you dont need one.

Dave - When do you plan on turboing your car? Once I drop in my motor I will be selling my SFMU to get a 1:1 FPR and I will be selling my injectors. This setup will support 13psi of boost. My car has ran perfect will this setup, I bought both brand new and they are only 1 yr old. They will probably be for sale in June or July.

Remember Dave, you have put a lot of money into your car already. Spend a little more and you will be much better off in the long run.

[david-b]

Originally Posted by SilvrEclipse

Ok, first off DO NOT buy a FMU. I used one when first turboed the 420a and it really doesn't work that well. It leaked air pressure and made me go lean. You have to run a 12:1 ratio on stock injectors which puts fuel pressure over 100psi at about 7psi of boost. Not that good IMO. You can run the stock FPR with this setup also.

Go ahead and spend a little more money and get the SFMU. Its a little more expensive but works a hell of alot better. Also I would upgrade the injectors while your at it. With the SFMU this acts as a FPR also so you dont need one.

Dave - When do you plan on turboing your car? Once I drop in my motor I will be selling my SFMU to get a 1:1 FPR and I will be selling my injectors. This setup will support 13psi of boost. My car has ran perfect will this setup, I bought both brand new and they are only 1 yr old. They will probably be for sale in June or July.

Remember Dave, you have put a lot of money into your car already. Spend a little more and you will be much better off in the long run.

I want to do a full motor rebuild, since it won't cost that much because I'm basically just doing the bottom end and adding a turbo. HOWEVER, I still want a turbo now. However, with money right now, I know it's better for me to hold off. I'm not even sure what I'm going to be doing with the block firstly.

Maybe I'll just wait until you sell yours. However if I'm doing a full rebuild, then do I really want to only be running 13psi? Probably not. So then I would have to upgrade again then right?

[Thor06]

Yeah, dont bother with the FMU. Matter of fact, why dont you just skip the SFMU and go straight to the STFU? If you've really got some money burning a hole in your pocket, you could get the add on and have the whole STFUNOOB. That would be tits. Or, you could just get the all superior 4g63.

Ok, Thor's done post whoring for the day. Time for teh hoemwerks.

[david-b]

Originally Posted by Thor06

Yeah, dont bother with the FMU. Matter of fact, why dont you just skip the SFMU and go straight to the STFU? If you've really got some money burning a hole in your pocket, you could get the add on and have the whole STFUNOOB. That would be tits. Or, you could just get the all superior 4g63.

Ok, Thor's done post whoring for the day. Time for teh hoemwerks.

Or I could build a beast of a 420a.... ya... that sounds like a plan.

[SilvrEclipse]

I didn't know you were going to build it also. What are you using for engine management? If you going with Megasquirt then I wouldn't use the SFMU either, just go with a 1:1 FPR. If your going to run the stock bottom end for a while and only use the SAFC to adjust then the SFMU will work fine. Also if your running the stock bottom end I would run the injectors I have also. Slightly bigger than stock so you wont run out of fuel but if you try and go too big without Megasquirt you wont get the car to idle worth a shit. It really depends on how long you will be turbo before you build it. You should be fine for a year or 2 before you blow it up like mine.

[david-b]

And that's what I don't want to do is to blow it up. That head I built was supposed to take a couple months to do... and it ended up taking 2+ years. I don't want that happening with a block.

So I think it's best to just wait until I get the build done (or started for that matter) and just do everything all at once. Probably better because then I won't be buying the same parts numerous times or whatnot.

I don't even know how much in the end I'm looking to put down. Just wanted some info on FMUs and all.

[SilvrEclipse]

Well I hope I helped you out some. Dont be scared about blowing up your motor. The only reason I had problems was because of the internal wastegate creep mixed with a shitty FMU and stock injectors. I leaned out to much and damaged the rings in the first 2 months I was boosted.

Keep the boost under control and have the fuel to fall back on if the boost does spike and you will be fine. I would deffinately boost the motor first and then start on a block. Like you said it might take longer than expected so you mise well enjoy the boost for a while. Also you will learn how to handle the extra power. Going from no boost to 18psi would be hard to handle with the crappy FWD.