4500 rev limit

[1995240sxSE]

ok I have searched and got only 1 result similiar. I got a lot acomplished with my car in the past week. I got the power to the wheels now. I am able to drive her now. Only problem is I cant get it to rev past 4500 rpms. It sucks. 5th gear is the only fun gear cause it takes so long to hit 4500 rpms. It sounds like kinda a popping or a car thats running short of all cylinders. I am thinking this is spark related. I am running 9 psi now. I have my 6 btm set at 1 but am thinking 9* pulled at 9 psi might be too much but I am scared to lower it down an detonate this motor! I am kinda partial to my ringlands! When I hit 4500 my wideband is just saying rich! I have tried messing with afc but also scared to lean out when in boost. Any help would be appreciated!

[Florida240sx]

lol that is wicked retarded. Change it to .5 4.5 is plenty safe for 9psi you should probably be at 3 or 4 depending on octane. Lot of people don't retard timing at all for 8psi...What is your sparkplug gap at?

[Daily Driven 240]

Hey im not sure but i think the factory ecu has a rev limiter or cut off as you wish in 4th and 5th gear at 4,500rpm's. And if thats not the case are you running your stock maf? maybe your maxing your maf out when you reach 4,500rpm's in 5th gear.

[S13FX]

Throw some specs of your car on here broski.

But yah there is a rev cut off between 4500 and 5000, on manuals and it sounds like a rev limiter bouncing off when it happens.

If your car goes past 4500 and just starts loosing power, might be spark blow out or too retarded.

[1995240sxSE]

I have a q45 maf so pretty sure that aint maxing out. It feels like timing. I have 480 cc injectors and a walbro 255. I am gonna turn it down to .5 and try that out. Dont hate on me but I had been fouling plugs out and the last set I put brk 5e's in there ungapped. So I have no clue what they are gapped at, and I had forgotten that it was like that until someone had just said that!

It isnt my revlimiter/speed limiter cause it does it in 1st gear! Also I only have a speed sensor hooked up to my transmission nothing else so there is NO governor! Also auto ecu with manuals transmission

[coolbone28]

Does it do it if you just rev up in neutral too?

[1995240sxSE]

no in neutral it will rev up fine all the way 6500+ no problems or sputtering!

[coolbone28]

well i would put in some new plugs (bkre7's) and get those suckers gapped propperly.

[LEMHEAD16]

AFR's that are too rich to ignite will be the weakest link in a bad ignition system. Lean it out a little bit at least into the low tens. Running too rich is as bad for your engine as running too lean. Blowing lots of fuel by the ring lands will wash teh oil off the cylinder walls and then you can say good bye to that motor.

[1995240sxSE]

yea I will get it good when I get back from vacation. I am leaving for the airport in 40 minutes!!! Yea virginia here I come!

[1995240sxSE]

I am back from vacation and hitting the car again. It only goes rich when into boost. For a half a seccond then I shift. I turned the 6 BTM down to .5. Not a bunch of change 3rd gear hit lik 4700 rpm's then it started missing. The car is still fun to drive, but I am not even into the power band yet. I hafta wait until payday to get some new plugs the 7e's again do they make a 6e? and gonna gap to .033????

Another question would having wideband in shortband o2 hole cause problems. IE no shortband at all???? I was thinking this could be my issues why my afr's are all over the place!

[Logan76]

not having your 02 sensor hooked up would cause you to run ****ty and rich, only in closed loop, when you enter open loop your car is running straight off your maf.

[480sx]

I think most widebands have a narrowband output, so you should be able to hook it up. What wideband system are you using? I know Zeitronix has this...

However it doesnt explain your problem, because after like 70 percent throttle your ecu goes into open loop and doesnt use the O2 sensor at all.

[1995240sxSE]

ok my problem was in out settings. I have a q45 maf. I had it 2 in 6 out. It should be, for my car, 1 in 6 out. revs up like a champ. Me and a buddy went for a cruise and he made me sad. he has a rb20 and I wasnt doing so hot. after we got done messing around I started messing with safc settings and tried in in out and damn what a difference. Also gas milage went thru the roof. I put 10 in before the fix and went thru it very fast. After I fixed it 10 bucks again and the gauge hardly moved! I am happy, well happier.

My wideband is a plx m-300 with a analog output for shortband. I have that hooked to my shortband afr and the wideband and shortband show opposites?????? Shortband says rich and wideband says 14.~. and in boost its the opposite wideband says rich and shortband says lean. What is the deal with this??????

[480sx]

Ignore the narrowband output, its going to jump all over the place. In boost, your narrowband o2 sensor feedback isnt typically going to be used by your ECU anyway, it would be in open loop operation.

[1995240sxSE]

I understand ignore narrowband if hocked to narrowband 02 sensor, but ran from the plx m-300 shouldnt it be accurate?