I have a 88 fox with a sn93 around 8-9 lbs of boost and 255 pump. My Question is can I get it tuned with the 30s injectors and FMU. I didnt want to buy 42s since i just brought the 30s or do I need the 42s. Thanks
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I have a 88 fox with a sn93 around 8-9 lbs of boost and 255 pump. My Question is can I get it tuned with the 30s injectors and FMU. I didnt want to buy 42s since i just brought the 30s or do I need the 42s. Thanks
We ran 30's without an fmu and may have upped the fuel pressure and rescaled the injectors. I know for a fact it didn't have a fmu with the 30's. They will work, but the 42's will leave you more room. Since you already have the injectors run em but get a wideband 1st.
What mass air are you running?
Quote:
Originally Posted by 88t.birdsc
pro-m 80mm mass air
You should have room with that mass air.
Afr, fuel pressure and timing are the keys. A lot of adjustable fuel pressure regulators have a 1 to 1 boost ref ratio which work well. I had a kirban with the 30's. The 42's though have plenty of room.
This is what I have on my fox. Can you explain how the 1:1 adjustabble regulator works? is this basically an FMU? I just bought one and got rid of the FMU, so now Im playing with my fuel pressure to get my AFRs in tune, Im too rich right now 10.8 WOT with 45psi (vac off) and stock timingQuote:
Originally Posted by 88t.birdsc
Fwiw, my stock regulator on sn95 fuel rails appears to be a 1:1 ratio meaning fuel pressure is raised 1 psi for every 1 pound of boost. On one of the old setups my tuner acutally ran the 19#s at a very high rail pressure and rescaled the injector slopes to make the computer think it had bigger injectors. It worked for awhile till one of the injectors started acting up. I wouldn't recommend it but was too cheap, lazy or just wanted to see if it was possible at the time. :freaks:Quote:
Originally Posted by hey its me
What are your list of mods?
Mike
My mods are. COMPLETELY stock 92' 5.0 long block, except:Quote:
Originally Posted by 88t.birdsc
30# injectors, Matching 80mm proM MAF, Paxton boost reference FPR, Zeitronix wideband A/F gauge, sn92 with a 4" upper pulley (most iv seen is 5#'s of boost), Anderson power pipe, Electric fan, Shortie headers, h-pipe, magnaflows, and a semi built AOD. NO TUNE or FMU. stock timing.
So is my paxton fuel pressure regulator like an FMU in a way?
No, fmu's are used to block the return of fuel going to the fuel tank resulting in high fuel pressure. Fmu's are activated for the most part when they see boost at wot. An adjustable fuel pressure regulator would raise or lower fuel pressure under all engine conditions. Fuel pressure variations from the stock spec will affect air fuel ratios at idle, part throttle, cruise, wot, open and closed loop. Without a tuning device it will be difficult to get around closed loop and adaptives that the computer will use. Your target afr at wot should be 11 or 11.5 to 1. A tuning device would be extremely helpful to get things dialed in.Quote:
Originally Posted by hey its me
Mike
I have an 87 GT with Speed density..I run 10 psi i run my timing locked at around 25 degrees, and FMU with 19# injectors I use a snow performance Stage 2 meth kit...I run one step colder plug, No tuning device.No ignition box.The car is a convertible,AOD with a shift kit.3.55's weighs with me in it 3750 lbs..last yr Just playing around with the timing and Meth set-up running Drag radials with 28 psi in them i ran a 1.8 60ft and a 13.3 @ 104 MPH...It had alot more in it..But i couldnt run it anmore that day got kicked off..LOL...NO ROLL BAR...i went faster then i could in a convertible without safety equipment...My point is Yes a tune is Important,,,Bigger injectors also but for what i got into my car 12's are just a step away..Not bad considering its a back yard tune...lol...I drive the car daily also...weather permiting...
We're very close on the times and weight. With my aod and cam combo 3rd doesn't seem to pull hard enough. How do you think she'd run with a gear or cam change?
http://s1194.photobucket.com/albums/aa373/tbirdsc/?action=view¤t=tbirdyno.mp4#!oZZ1QQcurrentZZ http%3A%2F%2Fs1194.photobucket.com%2Falbums%2Faa37 3%2Ftbirdsc%2F%3Faction%3Dview%26current%3Dqtr_pas s.mp4
Quote:
Originally Posted by 88t.birdsc
My GT is completely bone stock from the intake to the oil pan..The mods are as follows...70 mm tb...Mac shorty headers,mac off road H-pipe,Flowmaster cat back the older 40 series..190 lph fuel pump,Aeromotive fpr,anderson ford 4 inch power pipe,Snow performance stage 2 meth kit,The car is still speed density.It has a mild stall convertor,3.55's..10 psi...My car pulls hard in 3rd gear..it shifts 1st quick 2nd quick holds 3rd nice...The times i ran last yr werent my best im thinking High 12's easy..I was running way rich with the Meth kit..and i added more timing now too...What is your 1/8 mile that tells alot?...
I wouldnt do a cam Change maybe 4.10's ?....thats what they say for an AOD...thats what i hear...