maxi-o's 40 dollars adjustable FMU conversion
09-17-2003, 10:26 PM
#1
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maxi-o's 40 dollars adjustable FMU conversion
Hi all:
Before I start, I want to thank Mardigrasmax for giving all the advice and help me to trouble-shoot.
I have been looking for a solution to my super high fuel pressure (>100psi)....I thought about adjustable FPR, FMU, or S-FMU from vortech. so finally I've made my decision by getting a bleeder valve for the FMU. Vortech makes a bleeder valve for their FMU. This is what it looks like:
this is simple device. you replace your old vacuum hose adapter on the fmu with this one. it has a **** so you can turn it to bleed off boost. This thing fools the FMU to think that it's getting less boost, so the FMU will deliver less fuel to the engine. It can only lower 1 unit on the FMU. so if you have an 8:1, the lowest you can go is 7:1.
however, here comes new problem....my blow-off valve, FMU, and FPR are sharing the same vacuum from the manifold (I think for 5th gens, there's only one vacuum outlet from the manifold). Once I made the FMU leak boost, it also leak vacuum thru the small hole next to the **** (see pic). If I turn the **** too much, the BOV will not work because it cant sense any vacuum and I read 42psi of base fuel p. because it also leaks vacuum at the stock FPR.
as Mardigras suggested, I can attach a vacuum check valve onto that hole to hold the vacuum but release any boost. I got one from a local auto store. But how am I going to attach onto the bleeder valve? that hole is threaded, but it is a 1/16 NPT and no one makes 1/16 NPT for industrial use (the smallest you can get is 1/8 NPT)
so this is what I did....looks ghetto
I took a palstic tee and I used a lighter to melt one opening. Then I screwed in one unmelted end into the hole and attach a piece of vacuum hose onto the other unmelted end. Finally I attached the vacuum check vavle to the hose.
---------------------------------------------------------------------
as a result.....no more +100psi fuel p. at redline. the fuel p. along the rpm curve is lower than what I used to see. Mardigras told me that it needs a dyno-tune but I havent had a chance to do it. The EGT is higher than before.....a run from 3rd to 4th, 75mph to 110 will raise my EGT from 670 to 820C where I usually get a 780C peak. The car felt faster from butt dyno, esp at the top end. I am still adjusting it to see a good EGT and fuel p. value. I hope that I havent done any damage to the car because I do see the fuel pressure is still building up.
thx for reading this long post.....
any comment or suggestion are welcome.
Before I start, I want to thank Mardigrasmax for giving all the advice and help me to trouble-shoot.
I have been looking for a solution to my super high fuel pressure (>100psi)....I thought about adjustable FPR, FMU, or S-FMU from vortech. so finally I've made my decision by getting a bleeder valve for the FMU. Vortech makes a bleeder valve for their FMU. This is what it looks like:
this is simple device. you replace your old vacuum hose adapter on the fmu with this one. it has a **** so you can turn it to bleed off boost. This thing fools the FMU to think that it's getting less boost, so the FMU will deliver less fuel to the engine. It can only lower 1 unit on the FMU. so if you have an 8:1, the lowest you can go is 7:1.
however, here comes new problem....my blow-off valve, FMU, and FPR are sharing the same vacuum from the manifold (I think for 5th gens, there's only one vacuum outlet from the manifold). Once I made the FMU leak boost, it also leak vacuum thru the small hole next to the **** (see pic). If I turn the **** too much, the BOV will not work because it cant sense any vacuum and I read 42psi of base fuel p. because it also leaks vacuum at the stock FPR.
as Mardigras suggested, I can attach a vacuum check valve onto that hole to hold the vacuum but release any boost. I got one from a local auto store. But how am I going to attach onto the bleeder valve? that hole is threaded, but it is a 1/16 NPT and no one makes 1/16 NPT for industrial use (the smallest you can get is 1/8 NPT)
so this is what I did....looks ghetto
I took a palstic tee and I used a lighter to melt one opening. Then I screwed in one unmelted end into the hole and attach a piece of vacuum hose onto the other unmelted end. Finally I attached the vacuum check vavle to the hose.
---------------------------------------------------------------------
as a result.....no more +100psi fuel p. at redline. the fuel p. along the rpm curve is lower than what I used to see. Mardigras told me that it needs a dyno-tune but I havent had a chance to do it. The EGT is higher than before.....a run from 3rd to 4th, 75mph to 110 will raise my EGT from 670 to 820C where I usually get a 780C peak. The car felt faster from butt dyno, esp at the top end. I am still adjusting it to see a good EGT and fuel p. value. I hope that I havent done any damage to the car because I do see the fuel pressure is still building up.
thx for reading this long post.....
any comment or suggestion are welcome.
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09-18-2003, 09:56 AM
#3
Originally Posted by bags533
what is your peak FP now?
800+ is not that bad to me.. but I may be wrong.. 1 step or 2 step colder plugs??
800+ is not that bad to me.. but I may be wrong.. 1 step or 2 step colder plugs??
I have 1 step colder....800 seems a bit high to me (we are talking about celcius, right?) and if I dont loose any boost, it wont go up that high that fast.
you interested in getting one?
09-18-2003, 10:35 AM
#4
Originally Posted by [maxi-overdose]
peaked at 100psi, before it was >112.....to the red zone on my gauge.
I have 1 step colder....800 seems a bit high to me (we are talking about celcius, right?) and if I dont loose any boost, it wont go up that high that fast.
you interested in getting one?
I have 1 step colder....800 seems a bit high to me (we are talking about celcius, right?) and if I dont loose any boost, it wont go up that high that fast.
you interested in getting one?
Not at this time..lol.. just comparing FP to mine.
yeah Celcius, I heard 900 is bad... also depends on location of your probe
If your at 8 psi or higher you could go to 2 step colder and that should cool egt's as well
09-19-2003, 08:07 AM
#5
Originally Posted by bags533
Not at this time..lol.. just comparing FP to mine.
yeah Celcius, I heard 900 is bad... also depends on location of your probe
If your at 8 psi or higher you could go to 2 step colder and that should cool egt's as well
yeah Celcius, I heard 900 is bad... also depends on location of your probe
If your at 8 psi or higher you could go to 2 step colder and that should cool egt's as well
my EGT probe is on the ypipe...in between the exhaust manifold. so my reading should be a little lower than ppl who tapped it into the exhaust manifold.
you have auto, right? just wondering what's your EGT reading when you boost at a 75mph rolling, downshifted to 3rd from 4th and let go off the pedal at 110mph.
do you have 2 step colder plugs? if you do, do you notice the EGT drops after your install them? I heard that when you go down a step colder, you will lose some mid-range power, that's why I am still using the 1step.
thx
09-19-2003, 09:29 AM
#6
Originally Posted by [maxi-overdose]
my EGT probe is on the ypipe...in between the exhaust manifold. so my reading should be a little lower than ppl who tapped it into the exhaust manifold.
you have auto, right? just wondering what's your EGT reading when you boost at a 75mph rolling, downshifted to 3rd from 4th and let go off the pedal at 110mph.
do you have 2 step colder plugs? if you do, do you notice the EGT drops after your install them? I heard that when you go down a step colder, you will lose some mid-range power, that's why I am still using the 1step.
thx
you have auto, right? just wondering what's your EGT reading when you boost at a 75mph rolling, downshifted to 3rd from 4th and let go off the pedal at 110mph.
do you have 2 step colder plugs? if you do, do you notice the EGT drops after your install them? I heard that when you go down a step colder, you will lose some mid-range power, that's why I am still using the 1step.
thx
My egt probe is about 2 inches from my turbo in the reverse y-pipe.. so my readings are a little lower than avg. from what I have read.
My egt's when @ wot climb to 750c and hang out around there.. at partial throttle about 500 or so.
And I have also heard about the mid range drop in 2 step colder plugs.. but if your worried about egt's then that is the way to go.. or ad more fuel.
Have you dyno tuned? or used an A/F gauge on the dyno to see what a/f you have?
i run 1 step colder
09-19-2003, 10:02 AM
#7
Originally Posted by bags533
well my car is no longer running..lol.. tranny died..
My egt probe is about 2 inches from my turbo in the reverse y-pipe.. so my readings are a little lower than avg. from what I have read.
My egt's when @ wot climb to 750c and hang out around there.. at partial throttle about 500 or so.
And I have also heard about the mid range drop in 2 step colder plugs.. but if your worried about egt's then that is the way to go.. or ad more fuel.
Have you dyno tuned? or used an A/F gauge on the dyno to see what a/f you have?
i run 1 step colder
My egt probe is about 2 inches from my turbo in the reverse y-pipe.. so my readings are a little lower than avg. from what I have read.
My egt's when @ wot climb to 750c and hang out around there.. at partial throttle about 500 or so.
And I have also heard about the mid range drop in 2 step colder plugs.. but if your worried about egt's then that is the way to go.. or ad more fuel.
Have you dyno tuned? or used an A/F gauge on the dyno to see what a/f you have?
i run 1 step colder
so now wat? 5spd conversion? 
hmmm...see, your EGT stays, but mine doesnt...it just keep going and it wont stop until I let go of the pedal. I dont want to add more fuel by increasing the fuel pressure.....maybe try the S-AFC.
nope, I havent tuned my car yet, I just did a baseline.....I supposed to lean my super rich AFR out a little with this bleeder valve. But now the EGT problem just makes me nervous. I have the fuel pressure and everything is working fine. Now I have to look for other causes. My exhaust has been rattling again and maybe it is a good time to take out the ypipe and check the flex.
09-19-2003, 03:19 PM
#10
Originally Posted by [maxi-overdose]
just wondering, bag...how did the tranny blow up?
WELL... I drive my car like I stole it .. just about EVERY day.
I keep turning the boost up, doing brake boosting launhces, brake boosting highway racing, street racing , street racing , highway racing, turning up the boost, did I mention street/highway racing?
It was fun.. beating cars taht should have blown my doors off and hanging with cars that I should not have been able to see...
and I don't know what to do.. Car is sitting in my apt. complex and I am getting rides to work..
can't deal with it now and looking at a 2nd vechile...
Only time will tell.
and yeah Mine reach 750 pretty quick.. before I reach 115 in 3rd , but they stay there.
You can get your A/F read and play with your "valve" and try and make it "safe" as possible...
What do your plugs look like?
09-22-2003, 08:24 AM
#13
Originally Posted by thebigsadler
it's almost a cartech fmu now 
Originally Posted by bags533
You can get your A/F read and play with your "valve" and try and make it "safe" as possible...
What do your plugs look like?
plugs look fine I guess.....a bit brownish on the insulator and the tip is dark brown.
I am tunning the valve myself by obesrving the fuel pressure...I know there's fuel going to the injectors...but just cant explain the cause of high EGT. I took off the ypipe too this weekend and the flex section is fine, no clotting.
Originally Posted by Y2KevSE
I have an extra Cartech.
from Jane's car? she told her SC kit?
09-22-2003, 09:16 AM
#14
Originally Posted by ejj
How much?
10
10
Originally Posted by [maxi-overdose]
from Jane's car? she told her SC kit?
09-22-2003, 09:20 AM
#15
Originally Posted by Y2KevSE
Yup she sold her SC.
ic~ someone was really interested in Jane's SC kit from last nor-cal meet. dunno if it is the same person
so what's next for her? turbo?
09-22-2003, 10:25 AM
#16
Originally Posted by [maxi-overdose]
ic~ someone was really interested in Jane's SC kit from last nor-cal meet. dunno if it is the same person
so what's next for her? turbo?
so what's next for her? turbo?
Next..... new car. Her Max was too slow.
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