ignition breakup or spark blowout ????????
08-16-08, 09:32 AM
#1
ignition breakup or spark blowout ????????
guys i need some good insight here
i need to know opinions with reasons behind them for this
when on the highway crusing in 5th and i down shift to 4th around high 3k rpm range and car builds boost fast (t67dbb) i hit about 19ish 20psi and car bucks a few times then shuts off . i would pull over turn key off and restart no problem
could this be spark completely blown out and cyl being flooded with fuel . i do notice egt temp climbs fast while in this 4th gear while boost builds but funny thing it doesnt happen too much if i am in higher rpm band while doing 4th gear pull doesnt happen at all with 2gear pull or 3rd gear pull
could this be too much timing advance in that rpm range and makes car shut off because reg knock from knoeck sensor and pulls timing to the point of shut off
car is a 97 sc300 na-t so its obdII
550 inj
t67dbb 68back
boostlogic manny and piping
map ecu
2.5headgasket
ngk plugs 6097 gapped at .024-.025
running around 19 to 20psi is this too much boost for stock ign with no hks twin power
i am thinking spark blow out completely and with fuel dumping no chance of reigniting while under boost
i need to know opinions with reasons behind them for this
when on the highway crusing in 5th and i down shift to 4th around high 3k rpm range and car builds boost fast (t67dbb) i hit about 19ish 20psi and car bucks a few times then shuts off . i would pull over turn key off and restart no problem
could this be spark completely blown out and cyl being flooded with fuel . i do notice egt temp climbs fast while in this 4th gear while boost builds but funny thing it doesnt happen too much if i am in higher rpm band while doing 4th gear pull doesnt happen at all with 2gear pull or 3rd gear pull
could this be too much timing advance in that rpm range and makes car shut off because reg knock from knoeck sensor and pulls timing to the point of shut off
car is a 97 sc300 na-t so its obdII
550 inj
t67dbb 68back
boostlogic manny and piping
map ecu
2.5headgasket
ngk plugs 6097 gapped at .024-.025
running around 19 to 20psi is this too much boost for stock ign with no hks twin power
i am thinking spark blow out completely and with fuel dumping no chance of reigniting while under boost
08-16-08, 12:00 PM
#2
Lexus Test Driver
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fwiw: My plug blow out / mis-fire issue was solved when I re-gapped the 6097 from about .28 to about .26 with ~18psi on CA 91 oct pump gas.
You're already at .24 gap
The three suggestions for me were re-gap plugs, coil packs and ignition wires in that order, the plug regapped solve my issue and I went no further.
T61 single, 2jzgte, 700cc top feed, Apexi NEO, Blitz EBC making 440 whp. I'd offer suggestions but your situation is past my meager abilities.
You're already at .24 gap
The three suggestions for me were re-gap plugs, coil packs and ignition wires in that order, the plug regapped solve my issue and I went no further.
T61 single, 2jzgte, 700cc top feed, Apexi NEO, Blitz EBC making 440 whp. I'd offer suggestions but your situation is past my meager abilities.
08-16-08, 06:36 PM
#3
Lead Lap
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i had a spark breakup problem too. Im running a pt67 also. i was gapped at
.26 and started getting breakup around 18 psi. we couldnt get past 369 hp. then we regapped it to .19 and got 509 hp at 23 psi but that was maxing out the stock ignition.
I wanted more so i installed the hks DLI and made 543 with same boost.
my opinion is either gap it lower or install a DLI.
.26 and started getting breakup around 18 psi. we couldnt get past 369 hp. then we regapped it to .19 and got 509 hp at 23 psi but that was maxing out the stock ignition.
I wanted more so i installed the hks DLI and made 543 with same boost.
my opinion is either gap it lower or install a DLI.
08-17-08, 05:29 AM
#4
i had a spark breakup problem too. Im running a pt67 also. i was gapped at
.26 and started getting breakup around 18 psi. we couldnt get past 369 hp. then we regapped it to .19 and got 509 hp at 23 psi but that was maxing out the stock ignition.
I wanted more so i installed the hks DLI and made 543 with same boost.
my opinion is either gap it lower or install a DLI.
.26 and started getting breakup around 18 psi. we couldnt get past 369 hp. then we regapped it to .19 and got 509 hp at 23 psi but that was maxing out the stock ignition.
I wanted more so i installed the hks DLI and made 543 with same boost.
my opinion is either gap it lower or install a DLI.
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