97grnrs

i have an ls in my 91 hatch. runnin stock 91 LS obd0 ecu and stock injectors. 255 lph fuel pump and a 12:1 fmu. i am running about 9 psi right now on a custom setup i made , i have the ngk 7 series plugs in.. and my timing is retarded to about 10* at idle. after about a week or so of driving the car will start to pop and sputter if i try to get on it good.. when i pull the plugs they look like car was running real rich which it prob is runnin a lil on the rich side. but what can i do about this? should i go to a 6 or 5 series plug or what? my gap is at .28 right now

if worse comes to worse could i run it on my crx SI ecu to lean it out a lil or would that not work?

drintegra

how do your plugs look? That will determine the likely cause of the fouling.

oscarmayer

what if it's your sparkplug gap?
Try setting the gap to .030 and see what happens.

Doodoo

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 97grnrs &raquo;</TD></TR><TR><TD CLASS="quote"> runnin stock 91 LS obd0 ecu and stock injectors. 255 lph fuel pump and a 12:1 fmu. </TD></TR></TABLE>

This is your problem. Too much fuel. Fix this and you will not foul your plugs as fast. I ran the same setup, years ago.

97grnrs

well how do i fix that? it is what it is basically.. all i can do is advance or retard timing and or run hotter plugs .. i do have a crx si ecu which will run it ? do u think it will run a lil leaner then?

97grnrs

i tried the si ecu.. car ran poorly. so i put in a set of 6 series plugs and put the ls ecu back in it seems ok so far.. but if i wanna lean it out a lil more can i get an adjustable FPR and just lower my fuel pressure at idle to make it less when im in boost or will that not work? if it will what should i set it at , at idle?

JDMs1eeper

why is it running rich? Your running a stock ECU w/ stock injectors. Unless you have the highflow Walbro wich sometimes can take your fuel pressure from 43.5 to 55-60.

hondaeg8

you have the walbro fuel pump, which more than likely bumped up your fuel pressure to about 55psi at idle, so check that.

if it did, then you need to buy an adjustable fpr and turn the fuel pressure back down to stock settings.

IMO, your timing is too much retarded. a general rule of thumb, you should retard timing .5 degrees per 1lb of boost. you have yours retraded 6 degrees. i would just retard it 3-4 degrees. i ran ls turbo at 10psi and only had my timing retarded 2 degrees via distributor.

look at this chart:

http://www.dansmc.com/Spark_Pl....html

JDMs1eeper

alot of safe tunes Ive seen knock at 1* per psi. wich would be 10* per @ 10psi. 2* retarded at 10psi is like .2* per psi. ringlands are very weak... check plugs and keep it at 1*/1psi pull unless you see that u need more timing out.

hondaeg8

its still alot IMO.

i was running 93 octane all the time and one step colder spark plugs. never had a problem with knocking or pinging with only have it retarded 2 degrees.

i was running a JRSC at 6 psi on a JDM GSR with a Kenji all motor chipped ecu and i only retarded my timing 1 degree and never had any problems. again, i always run 93 octane and i degree colder plug.

97grnrs

fuel press is 43 psi

hondaeg8

turn it down to 40psi.


get a different fmu... possibly a 10:1 or an 8:1.

you can just spring out the cash and get a Cartech fmu also.

97grnrs

what the diff between a cartech and my vortech? and also what would a 10:1 change? when car first started FP was like 40 then after it warm up it was like between 43-46 ish?? what should i set it at when car is full y warm?

AbitAvenger

you are in reading pa???

http://www.j-k-tuning.com

Have him chip your ecu street tune it and you won't have to worry about all of this FMU stuff, but you will need to get some injectors (DSM 450's work great and are cheap on ebay).

That is going to be your best and most reliable route

97grnrs

ya in reading

hondaeg8

fully warm my car is at 40psi.


cartech is adjustable. you can adjust it from 12:1 to like 2:1 or something like that.

97grnrs

i tried an adjustable and my FP wont get lower than like 46 psi at idle.. i cant figure it out.

hondaeg8

if your using a b&m one, that will be the reason why.

so you look at it like this:

46psi fuel pressure + (12*10) = too rich.

97grnrs

why would a b and m one not work?

oscarmayer

retuen outlet inside is not big enough.

97grnrs

i fixed it by drilling a small hole in the regulator.

mr_hahn73

Get rid of the fmu and get a real tune! That will be your best bet and close the gap on the plugs a little.

hondaeg8

drill it a little bigger. you need to get your stock fuel pressure lower.

i would just get a smaller ratio fmu, like a 8:1 or 5:1

97grnrs

well with the hole in the FPR its right again.. my plug gap is .28 that should be good right?

hondaeg8

so what was the outcome?