My friend has a question and i figured id post it for him "i am running 8psi on ex motor and i dont know if 12:1 fmu will work or not"

Thanks, Jim

 

search, it has been discussed a bazillion times. to answer the question though, get rid of the fmu and get proper fuel management like uberdata or crome. the fmu is probably good for around 6psi. i had one for a while and my car ran like crap.

 

i run 8 on my fmu and its fine.

 

FMU 12:1 + Missing link + Walbro255 + back timing down 6 degree's. Should run well. Id also put in 1 step cooler plugs, and do 3rd gear pulls and check plugs for AFR's, heat range, Detonation and all that good stuff.

I used to run FMU for over a year before switching to Uberdata. No problems, it was on a b18b LS.

 

any tuning?

 

With the FMU setup, its out dated VS' newer styles of engine managment. Basicaly if you have a Wideband in the car (PLX is a great example) you'll have an eye on air/fuel at all times. With timing you can set the base timing back .75 per lbs. 8psi = 6 degree's turned back. Or if you have a MSD ignition retard box, set it up to pull .75- 1. degree timing per PSI. The MSD box would be the best thing to use for timing w/ it. This way you have more timing at idle and out of boost.

Basicaly with this setup your making sure the AFR's are 12:1 or richer (lower number) , making sure your not detonating and make sure your plug is the right heat range for your application. IF you have it set up right, it should last you a good while .

If you ask me a FMU setup isnt a bad choice as long as you set it up correctly. It should give you what you want for a beginner booster that isnt planning on up'ing the horsepower past what the limits of a FMU can supply you.

If you had the cash to go Uberdata/Chrome or the like, it would be even better because you have the ability to fine tune your boosted car as if it came from factory. But not "everyone" can afford to go that route... nor do a lot of people plan on spending that kinda cash to become the fastest guy around. Some people are happy with the results a simple setup a FMU can bring you.

I went from a 14.8@91 LS swapped EG (street tire) to a 13.0@105 (street tire) with only 6-7psi and the FMU setup. Also on my B20 setup it went from 14.2@97 to a 12.7 @ 110 on a FMU on only 8psi. That to me is an awesome jump in performance that a simple FMU setup can bring. The fastest I've ran was a 12.2 @ 111 on 10psi on the LS w/ 22" M&H's. The LS made 242whp and 200ftlbs on 9psi

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDMs1eeper &raquo;</TD></TR><TR><TD CLASS="quote">With the FMU setup, its out dated VS' newer styles of engine managment. Basicaly if you have a Wideband in the car (PLX is a great example) you'll have an eye on air/fuel at all times. With timing you can set the base timing back .75 per lbs. 8psi = 6 degree's turned back. Or if you have a MSD ignition retard box, set it up to pull .75- 1. degree timing per PSI. The MSD box would be the best thing to use for timing w/ it. This way you have more timing at idle and out of boost.

Basicaly with this setup your making sure the AFR's are 12:1 or richer (lower number) , making sure your not detonating and make sure your plug is the right heat range for your application. IF you have it set up right, it should last you a good while .

If you ask me a FMU setup isnt a bad choice as long as you set it up correctly. It should give you what you want for a beginner booster that isnt planning on up'ing the horsepower past what the limits of a FMU can supply you.

If you had the cash to go Uberdata/Chrome or the like, it would be even better because you have the ability to fine tune your boosted car as if it came from factory. But not "everyone" can afford to go that route... nor do a lot of people plan on spending that kinda cash to become the fastest guy around. Some people are happy with the results a simple setup a FMU can bring you.

I went from a 14.8@91 LS swapped EG (street tire) to a 13.0@105 (street tire) with only 6-7psi and the FMU setup. Also on my B20 setup it went from 14.2@97 to a 12.7 @ 110 on a FMU on only 8psi. That to me is an awesome jump in performance that a simple FMU setup can bring. The fastest I've ran was a 12.2 @ 111 on 10psi on the LS w/ 22" M&H's. The LS made 242whp and 200ftlbs on 9psi </TD></TR></TABLE>

couldnt have been explained better!! FMU's arent the greatest, but if done correctly it will benefit you better than nothing at all, if running a FMU keep your boost low until you have the cash to work with a better tuning program, then go for higher boost

 

JDMs1eeper: Great explanation! Usually most people just say don't go with the FMU, they suck, but you explained how it could be used in the right way.

I still wouldn't run one, lol , just because I'll be to paranoid with it, lol.

 

I used to run them for years nothing is wrong w/ them if used correctly.

InlinePRO used FMU setups for years also, still do. (john's 11second S2000 is FMU powered)

 

what is the purpose of the missinglink ? do you need it if your going to run a low boost fmu setup ?

 

All the missing link does is trick the ECU into thinking that the air entering the intake manifold is the same as without boost. so the sensor doesnt read the boost.
most turbo hondas need a missing link or check valves. I am using check valves that I bought from petsmart usually you will need 1 check valve per 3psi of boost.

a missing link/check valves keep from signaling a "check engine light".

 

i would say search. but still its good to see info and not drama here. to the helpers

 

get a in-line fuel pump like a msd 1 and retard the timing alittle and you'll be fine. also get colder plugs and dont forget about the missing link have fun