popping and cracking under boost........

[BOOSTEDSUPRA]

sup guys, ok, im not new to working and tuning cars, but the 7m...seems to always give me a challenge, good thing i like that, lol.

working on my buddys car, pretty much same setup as mine, 60-1 turbo, stock fuel system on 440's and other goodies not relevent. now, under boost, at around 12-14 psi, its crackling like almost a fuel starving prob or timing. i set his car timing to exactly 10 per tsrm, is this simply the stock fp falling flat under boost? or because running higher boost i need to set timing different? only difference here between mine running higher boost, and his, i have boost controller, he turned his boost up by adjusting his waste gate. our turbo's are adjustable.

now i look at the guages, the wb isnt showing a lean condition, that i can tell, and the boost doesnt appear to be spiking, and aside from the cracking and popping, it still pulles pretty damn hard. any ideas guys? im stummped.:1zhelp:

 

[aznboik1mva]

running rich?

 

[BOOSTEDSUPRA]

doesnt seem like it. i wouldnt think a rich condition would cause such a thing. but... i am fairly new to turbo's, so....

 

[MKIII TURBO60-1]

probably running out of fuel, is your wb working correctly 60-1 on 440s at 14psi is unheard of

 

[wardog]

What fuel pump are you using and what regulator?

 

[hvyman]

probably running out of fuel, is your wb working correctly 60-1 on 440s at 14psi is unheard of

its not that big of a turbo. at 12-14psi with this turbo its only prob making 300-350 range. fuel pump could be maxed out tho but the 440s are not but it should be time for 550s.

 

[BOOSTEDSUPRA]

my car has walbro 255, stock 44o's on stock fuel rail with the 60-1 ball bearing turbo, i run a consistand 15psi, i can run 18 in short bursts and im just flirtin into the lean. his doesnt have the 255 pump, so i am thinking that may be what it is, but i dunno. you guys think fp over timing?

 

[MaxBoostedSupra]

I have been having the same problem. Running stock turbo @ 12-13 psi. and under full boost it seems like its sputtering and you can feel a slight let off and on thru the pull. Not jacking your thread but if anyone has the same prob or knows what the prob is.

 

[BOOSTEDSUPRA]

JACKER!!!! j/k since no one else is chiming in, and since i checked for boost leaks, vac leaks ect and found none. im pretty sure thats what it is. 23 year old fp just cant cope. i will let you all know the out come.

 

[BOOSTEDSUPRA]

ok, so here is an update on this car, i changed the fp to a 255 walbro, still doing same thing, almost more of a miss, rather than crackling and popping. its got new plugs, new wires, everything is set per tsrm. im just wondering..should i set the base timing a little off to compensate for his higher boost levels? i took it out last night and its spiking at 15.1 psi and fading to about 14ish. and holds good, and pulls hard. idk what else to check...i got him the same msd wires as mine, and i forgot what the plugs are, but there the jap ones that are recomended on here. i had the same in mine, but i thought they sucked, so i put my old bosch plus 4's back in, and my miss went away. and yes they are gapped. twice just for assurance, lol. any ideas guys? im at a loss atm.

 

[kamikazemkiii]

Are you pulling any codes?

 

[BOOSTEDSUPRA]

no, no codes, aaand.... what the hell is your little video?!?! that made me crack the fuk up!! lmao

 

[kamikazemkiii]

haha thanks, when u say no codes have you tried pulling them? or is the check engine light not on?

 

[BOOSTEDSUPRA]

ecu was cleared prior and checked for them. nothing showed up. honestly, imo, im not leaning tword the 440's giving out, looking at flow charts, the 440's should be keeping up. but idk. and it seems more like....maybe a miss, thats why im kinda thinking timing, but on a turbo car, not sure.

 

[WhtMa71]

What plugs are you using? What are they gapped to? Have you tested the coil packs?

 

[tekdeus]

What plugs are you using? What are they gapped to? Have you tested the coil packs?

It's probably plug gap. Mine sputtered under boost but went away with new plugs gapped to around .28 I think?

 

[BOOSTEDSUPRA]

i forget the plugs, i got them per the sticky on here about plugs, and there gapped per here and tsrm. forget the gap.

so my first assumption was corect? "spark blow out".... possibly? they are gapped bigger than .28 if i remember right, i wanna say .32 or .35 something like that.

 

[WhtMa71]

Yes. When I first put the motor in my car it ran terrible once in boost with .031 plug gap. Moved it down to .028 and it cleared it right up.

 

[Heavy D]

i had this same problem with my tercel, my problem was due to the timing on the distributor, maby it could be the same with the CPS, once i hit boost around 13 psi it had that popping sound and the fuel was fine, i would just mess with the timing and see what you get from there

 

[MKIIINA]

Check your plugs again. Could be they are just past their prime.