hitting redline or fuel cut??

[S13 King]

I got up on the car the other day (I have a blacktop SR)and it seems to either hit a redline or fuel cut around 5500-6000rpm. SR redlines at like 7500-8000 correct? I mean correct me if I'm wrong. Any ideas? I'm going to have the timing checked and check everything else for signs of detonation (which I pray to GOD its not!)

Let me know...

[Hijacker]

Fuel cut is like at 7500 or 7900. Can't remember where exactly. what kind of fuel mods do you have right now? fuel pump etc.

[S13240]

Fuel cut is not rpm dependent. Fuel cut is boost dependent. Most likely you're experiencing some minor mechanical difficulties or electrical. No rev limiter as well on manual cars except of course when you downshift too low and it goes kaboom!

[Phax]

Were you in 5th gear? My guess is that you hit the speed governor. I can peg the speed limiter on my S13 at about 7000 in 4th, or 4500 in 5th.

[S13 King]

i have stock fuel pump, but i'm getting the walbor 255 soonall the fuel system is stock.

going to start up grading soon

[quiksilvia]

if im in 5th, ill cut out at 5500rpm and my speed sensor isnt hooked up, i dunno what that means, but i have the same cut

[S13240]

Try hooking up your sensors guys. Probably a sensor issue.

[quiksilvia]

how so?

[S13 King]

well i was discussing this with my friend 240_Keyy he says its just the govt stop point.So i'm not worried about it thats what my shop also said. However I'm gonna begin the fuel mods next

[RiceBurner98sC]

well i was discussing this with my friend 240_Keyy he says its just the govt stop point.So i'm not worried about it thats what my shop also said. However I'm gonna begin the fuel mods next

I dont believe a point exiists with these swaps. I think the only "point" there is maybe be a speed limiter.

[S13 King]

well wouldn't that be in the ECU?

[RWmotion]

I have an S13 blacktop and also have this problem. When i am in 4th gear, going about 110 or so, the speed limiter kicks in. BUT, when i put it in 5th it obviously keeps pulling all the way up to about 127 or 128 (whatever the limiter is). Ive asked around, no one can really give me a straight answer. I would just assume it was an ECU issue.

[RiceBurner98sC]

I dont believe its an ecu issue persay because when you swap everything over, the majority of installers will wire your harness to the KA Speedsensor which has something to do with not being able to pick up a signal or something to that effect in 5 gear. I believe it fools the computer into thinking its always in 4th gear so the speed limiter is removed.

[RiceBurner98sC]

MAF....boooyahhh.

[dj_lennon_franz]

yer rev limiter hits exactly at 7600 on S13 redtops/blacktops...i think the rev limiter is a bit lower on S14/S15 motors...if youre experiencing fuel cut/rev limit at 5500-6000 rpms then something is not right

[msaskin]

Yeah. If you're hanging up at 5500 or so (basically, anything other than redline) you're hitting fuel cut. Basically, the ECU sees you leaning out too far and stops you before you blow something up.

You mentioned you're still on stock fuel pump...how much boost are you running? I'd bet you're running out of fuel pressure due to the stock pump not flowing enough.

~matt

[S13 King]

Yea my Fuel pump is stock KA pump (I know I know something I need to change). with my profec off its at 9psi, then with it on low boost is set at 10psi and high boost at 14.5 (15 being T25 range of efi).It seems to bogg when i'm on low boost and I'm guessing thats it has to do with the fuel pump.

[msaskin]

That boost level is WAAAAYY to high for a stock KA pump dude.

I tend to be very conservative, but I wouldn't run higher than about 7psi or so (basically, wastegate pressure) without an upgraded fuel pump (walbro 190 or 255)

~matt

[S13 King]

alright thanks for the suggestion. Well, I should have the pump here SOON, so until then i'll leave the Profec off and let it hold its own boost, which since i have exhaust, FMIC, PSI is somewhere around 9psi now if I remember correctly.