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S14 SR Falls On Face and chops up @4000rpm every gear

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4000rpm breaking up maf popping s14 sr
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Slideside-Deezy

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Discussion starter · #1 ·
Hey guys Deezy here, havent been around in ages, just recently picked up my 4th 240 now. Having some very retarded problems with it... Car is a 1992 hatch, with close to stock s14 sr in it. Ive researched tons and tons but cant find the same problem im having, and troubleshooting and guessing with other peoples simmilar, but not same problems is making me about ready to shoot myself in the face... i need HELP!!

Ok so heres the small list of known mods to the car (I fucked up and bought the car with swap already done, and not running right....):

S14 SR20DET w/stock t28
w/stock boost
w/stock piping and IC

NGK 7 i think plugs, gapped at 35

Wiring Specialties Premade s14->s13 harness

Aftermarket fuel cell with walbro pump, brand new inline filters and brand new regulator

Jim Wolff Technology tuned ECU for Z32 MAFS with 370cc injectors

Z32 TT MAFS with circuit sports? Pigtail z32 adapter plug thing..

stock manifolds

cat delete

Andddd thats pretty much it i believe... Problem im having is this:
First crank start, bounces idle real high from around 3k to 1k for about one minute then smooths out and idles around 1100rpm.. in neutral, smash gas and will rev to redline without skipping a beat.
Put it in gear, do a pull and it pulls solid untill 4000rpm then starts POPPING and breaking up and will not rev past 4 in any gear unless the throttle is feathered like a baby. If i drive it just shifting near 3800rpm and being normal, it backfires about 1 out of 3 shifts, but can not smell it running rich or lean, blowing no smoke at all. Pulled the spark plugs yesterday and they look perfectly fine, maybe just a tad bit of carbon.. My mechanic and i seem to believe it has something to do with the MAFS, because it did sit under my carport for a few months off the car, condensation maybe messed something up? idk im not a MAFS expert... i did clean it the other day aswell, not difference.. Anything that you guys sugest will help me, any questions or anything im missing i will answer stat. Any help is GREATLY GREATLY appreciated!!!!! Thanks in Advance!
-Deezy :feedback::gc-wmsmiley-this-to
 
Discussion starter · #6 ·
I put them at .028 and it DOES rev all the way now, kinda... Just doesnt have any power and still feels slightly sluggish but it doesnt stop at 4000rpm. When it cools down ill go drop them some more then check and update again.
 
#7 ·
I have no experience with the SR coilpacks, but it would have been my guess that they would have allowed a larger gap. .028 is NA + dizzy territory. I've had to gap my plugs in my KA (dizzy) w/ 11psi to .018. Just my $0.02 thoughts.

I would have initially suspected boost leak/ IC piping.
 
Discussion starter · #8 ·
Yea that was my first guess too, i went through all the piping and took it all apart and cleaned it all, hooked it up again About 4 times already. I think the spark plugs are the key. These are iridium plugs, i know im not "supposed" to gap them, but ive already gone from .045 to .028... Is it safe to go any lower on these? And will it Completely cure my slugging problem you guys think? Going from .035 to .028 has already stopped the cut, just dont want to harm the plugs going any lower... Thoughts??
 
#9 ·
Throw those away and get copper. Honestly.

Check your base timing too. That sounds to be off some. Coppers will ruin quick if you have detenation and irridums will just keep working until you blow the engine. Coppers are better for performance as well. Irridum is just better for longitivity, just get rid of them and use bkr7e coppers for now on
 
#11 ·
bmoses said:
I have no experience with the SR coilpacks, but it would have been my guess that they would have allowed a larger gap. .028 is NA + dizzy territory. I've had to gap my plugs in my KA (dizzy) w/ 11psi to .018. Just my $0.02 thoughts.

I would have initially suspected boost leak/ IC piping.
Click to expand...
I think the combustion chamber shape has some to do with it. I was unable to open my gap any with splitfire coilpacks but can notice a major improvement in cold starts with them. Also less random blow out or pops under boost but gap couldnt be opened
 
Discussion starter · #13 ·


:lamende:

I put the copper plugs you said in the car, and im not sure but i dont think it helped anything. havent checked the timing yet.. gotta get my hands on a light and a ka wire lol kinda difficult cause i think im the only 240 around here... and none in the junkyards..
 
#16 ·
yea, set your base timing and dont do pulls like that until its fixed. I can promise your hurting it doing that.

You dont have a wide band either do you? Every turbo car should have one.

Anyways I didnt say that the copper plugs were going to help anything, I was just saying dont run anything but coppers. They are easier to read, and will hopefully screw up if there is a problem which will clue you in to look into whats going on with your engine.
 
#17 ·
Slideside-Deezy said:
$$$ lol im working on a tight budget. Cant go buy parts that i dont need for my car atm. Got a baby on the way so this is lucky when it sees new shit lol. Ill find everything soon.
Click to expand...
but your vid does look like you need it....

Just drive it easy until its fixed because your going to break that car if you do too many pulls like that in the vid.
 
#18 ·
Find a local forum, any forum. Someone on a car forum in the area will have a timing light you can use. I found mine on a subie forum.

A WTB ad on Zilvia will net you the wire.
 
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240jake
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