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Dee
07-03-2009, 12:21 AM
OK so I took my car to the track tonight and I notice that every time I get around 5k rpm in 3rd gear my car sputters and loses power and it does it to redline. I'm running stock t25 turbo @ 10psi(no boost controller), 255lph fuel pump, stock FPR, ARC SMIC, stock bov.

I was thinking maybe plugs since I haven't changed them since the motor swap, but I thought I'd get a second opinion.


thanks
-Dee

My best run tonight but still slow because of the high rpm sputtering:

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Felipe
07-03-2009, 12:38 AM
maybe spark plugs... check your battery connections, my bro inlaw sr was doing that... posi cable was loose.:zzz: lol hope that helps
VQMaxFan
07-03-2009, 12:40 AM
yeah check the plugs, make sure the gap is set properly.
Dee
07-03-2009, 12:48 AM
what would be the best spark plug gap to set at? thinking about doing oil change & new plugs tomorrow.
GSXRJJordan
07-03-2009, 04:41 AM
yeah check the plugs, make sure the gap is set properly.

Yup, plugs are the first thing to check since a) they're an "unknown" when you get the motor, and b) they're cheap :)

Heat range 7 is what you're looking for, copper is fine (Iridiums perform the same, just for longer intervals - copper's good for >10k mi). Gap to .032", or 0.8mm.
Dee
07-03-2009, 12:21 PM
Just picked up some oil & Ngk7r's from napa I'll update later tonight with the outcome. Thanks for the help
[email protected]
07-03-2009, 12:32 PM
hey braaahhh i saw you shooting that fireball at irwindale last night ahaha
lilrusty
07-03-2009, 12:58 PM
if not your plugs then it might be one of your coils going out. happened to a buddy of mine. same problem as yours. we swapped out and problem went away. good luck...
GSXRJJordan
07-03-2009, 02:53 PM
if not your plugs then it might be one of your coils going out. happened to a buddy of mine. same problem as yours. we swapped out and problem went away. good luck...

True. With RB coils, it's fairly common on higher mileage motors for the insulation to wear thin, causing the coil to arc through the black rubber to the head, instead of delivering all of the spark to the plug. If plugs (properly gapped) don't fix it, try wrapping each coil in electrical tape where it meets the head.
Dee
07-03-2009, 05:17 PM
hey braaahhh i saw you shooting that fireball at irwindale last night ahaha

haha word, it was a fustrating night for me but I'm glad my boy caught that flame. Preety cool heh

if not your plugs then it might be one of your coils going out. happened to a buddy of mine. same problem as yours. we swapped out and problem went away. good luck...

True. With RB coils, it's fairly common on higher mileage motors for the insulation to wear thin, causing the coil to arc through the black rubber to the head, instead of delivering all of the spark to the plug. If plugs (properly gapped) don't fix it, try wrapping each coil in electrical tape where it meets the head.

I'll check the coils insulation out but since I already bought new plug I'm just gonna go ahead and swap them but I will check the gap of the old ones before I put them in.
Dee
07-03-2009, 10:38 PM
Well I found out what was causing my topend sputters and I'm almost too embarrassed to post it.


Turns out that it was a loose ground cable, the post on my battery wore down and I guess from racing last night it worked itself loose and was barely making contact. :duh::duh::duh:
GSXRJJordan
07-03-2009, 11:32 PM
Well I found out what was causing my topend sputters and I'm almost too embarrassed to post it.


Turns out that it was a loose ground cable, the post on my battery wore down and I guess from racing last night it worked itself loose and was barely making contact. :duh::duh::duh:

Haha, at least you've got new plugs :ghey: