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Fuel Cut Question

2334 Views 12 Replies 4 Participants Last post by  Warrtalon
Hey, to any of you gurus. i just did my boost controller with my buddy and i had it set for 20psi but i hit fuel cut all the time in higher gears. I was lookin for some tips on what i can do to stay away from it beside go down in psi. I did the forge Unos mbc. Also, what are some things i can get besides fuel cut retarders or a mail in that are reasonably priced and safe, is there anything? Im gettin a puel pump within the month also cause i know i should upgrade for higher boost settings. I also went a step colder in plugs today with some ngk R's. thx for the help again guys:dsm:
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Well, you have no need for colder range plugs. You don't need 8s until you're up near 350whp. I still use NGK BPR7ESs on my car running 12.0-12.2s. You shouldn't see fuel cut at only 20psi either. Are you sure that you're only hitting 20psi when going WOT in high gears? There's more load in higher gears, so the boost usually spikes/holds much higher. To get past fuel cut, you can just get a flash. A fuel pump is good along with a flash, but you don't need it just for running 20-21psi on pump gas. It's more needed when running much higher boost - I got mine since I run 24-25psi at the track on race gas.
Is it bad to run as cold of plugs as im running? ill recheck what my boost gauge reads today on my way to a local mitsu meet.
Yeah, it's not good. My car won't even boost properly without stuttering when I have 8s in on pump gas and low boost. 8s only work for me when above 5500rpm on race gas while pushing 24psi. Once I try to go on the street and roll into boost from low rpm, it sutters and misfires terribly. You don't want to use a colder plug than is necessary. Just get some NGK BPR7ES for $7 total.
I had the same problem in my DSM i switched to the 7es plugs and magnacore wires and i never had that problem again.
I've had BPR8ES' for about 3K miles (21psi./daily driver) with no problems. Checked them about two weeks ago; no fouling.
turbolarry said:
I've had BPR8ES' for about 3K miles (21psi./daily driver) with no problems. Checked them about two weeks ago; no fouling.
That's very strange. I can't boost in any gear below 5k rpm with 8s. I'm not making enough power yet to use them. The 7s are good all the way up to 350whp and some people still use them at that power level and beyond on the stock turbo.
yea, i have had no problems with them, no stuttering or misfireing at all. im runnin a strong 19 psi on pump gas with what seems to be a stronger runnin evo. i went to a local dsm meet a hour away with no problems or anything, and i daily drive it with no problems
Ok, well, just remember that there's no reason for you to go a range colder next time you get plugs.

Actually, you never said which ones you got. You only said they were one range colder.

Are you using BPR8ES, BR8ES, BPR7ES, BPR8EIX, or BPR7EIX?
yea ill go back to 7's as soon as i need new plugs. back to my amin point though, whats the best way to boost higher without fuel cut, flash, retarder, or something else?
A flash will do it or an SAFC if you have fuel removed. You must have the proper octane to boost higher, too.
BPR8ES straight from lancershop gapped at .28

How do you do it with a safc?

i know, i wanna go to a good 20-21 psi with 93 octane, and 110 leaded go to 24psi, but i have to order my test pipe first for that, but i hit fuel cut at 21 psi so i cant really go up to that pullin on the freeway when its as cold as it gets here because of the denser air
When you remove fuel on the SAFC, it's telling the ECU that there is less air crossing the MAF, which helps to delay fuel cut, since fuel cut occurs when a certain MAF HZ threshhold is eclipsed. So, the more fuel you have removed, the less air the ECU thinks the MAF is seeing, and thus the more you can boost before hitting fuel cut.

On my 05, I never once hit fuel cut except for in top gear when my boost was turned up and I rolled into boost from low RPM. I never got fuel cut at the track on 104oct (or 110oct) when drag racing at 24-25psi. I also never hit fuel cut at 21psi under any circumstance.
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