cutting out in boost need help

[supr67]

As the title says once I start to go into the power band my car starts to cut out like its losing spark Im runing tr6 plugs .032 gap msd opti msd coil stock icm. would I benifit by running a 6al box ???

[popo8]

I run a 6al box... But idk if its really a benefit.

I gap at .028




MEMBER @ LTXtech.com

[popo8]

And what are u running for a fuel system?

MEMBER @ LTXtech.com

[supr67]

walboro 255 and 42 lb ford green top injectors

[popo8]

Are u running a wideband?

Is this a new problem on an old set up... Or is this a new set up?

MEMBER @ LTXtech.com

[supr67]

Its a new set up I first noticed it when we started to dyno tune it using a wide band but it was having a small miss so I couldnt really start to tune it for power just made sure it was plenty rich so I didnt burn up the motor diagnosing the miss one day I made a test pull and it blew ignition fuse had icm tested it passed replaced coil fixed the fuse problem but still have this random miss through out im ordering plug wires this weekend but see no signs that they are arcing.

[popo8]

Its a new set up I first noticed it when we started to dyno tune it using a wide band but it was having a small miss so I couldnt really start to tune it for power just made sure it was plenty rich so I didnt burn up the motor diagnosing the miss one day I made a test pull and it blew ignition fuse had icm tested it passed replaced coil fixed the fuse problem but still have this random miss through out im ordering plug wires this weekend but see no signs that they are arcing.

Personally i think u need to tighten ur gap...

Also are u running a cooler plug?

I also question ur injectors and pump. My set up.maxed my old 340 pump thru 60 lb injectors at the 550 ish hp.mark.

MEMBER @ LTXtech.com

[supr67]

I am running a colder plug and I read that my pump would struggle much over 500 horse but im still runing low boost should be just shy of 460 horse

[popo8]

I am running a colder plug and I read that my pump would struggle much over 500 horse but im still runing low boost should be just shy of 460 horse

Try tightening up ur gap on a set of fresh plugs and lets go from there.

MEMBER @ LTXtech.com

[supr67]

ill tighten the gap this weekend they have five miles on them so should still be good Ill get back with you this weekend thanks for the help.

[popo8]

ill tighten the gap this weekend they have five miles on them so should still be good Ill get back with you this weekend thanks for the help.

Keep am eye on ur thread... Im sure others will post up as well. Im just the one here 24/7..lol

MEMBER @ LTXtech.com

[Still2slow]

I also run tr6's with a .028 gap and have never had a problem. I would recommend some sort of box like a 6al. I've been running an accel 300+ coil and box for 13 years without issue. It might not solve your problem but good to have no less. Wires are a good thing to try and hopefully that and a re-gap will clear it up. If your around 500 rwhp the walbro 240 and 42's should be good, that's what I'm running but the methanol injection takes some pressure off the injectors. Not sure what my duty cycle is though. Good luck with it

[supr67]

installed 6al box last weekend improved things but still cutting out under load randomly next up is plug wires and smaller gap ill keep everyone posted.

[supr67]

Just thought id let every one know ended up changing opti spark whole new car now ....

[NightTrain66]

edit - oops, my bad. I skimmed over the thread and did not realize that you had it figured out (omne post up).

I'll leave the below info as it may help others with similar problems . . . . . . - edit

-------------------------------------------------------------------------------------------------------------------------------

what RPM is is starting at?

what is the set up (compression ratio, how much boost, intercooler, cam specs, seat pressure, etc)?

what fuel (E85, 93 octane pump gas, race fuel, meth inj, etc)?

One thing to remember is that 10 psi of boost will also offset seat pressure on springs by about 20-25 lbs (more boost = more seat pressure loss). You have to run more spring pressure for a boosted set up than the lobes actually call for (and also use lobes that close the valves slower to give it all a chance to work). Just one more thing to check out.

I can't tell you the amount of times that someone will send me a graph of their boosted set up and the graph will be all squiggley at "X" RPM on up and no matter what they do with timing or fuel it just doesn't make any more power. Problem is that the valves are not staying closed and so boost is going back up intake, not trapping cylinder pressure, etc, once they reach that RPM. Once they tell me the cam specs (sometimes people use aggressive XFI, Voodoo or LSK lobes) and what the seat pressure is, the problem is right there in front of them. More pressure and/or different lobes will be the fix for them.

Sometimes they have a cam on a tight LSA (N/A cam/engine with boost added later on) and it is putting lots of the boost out the tail pipe and hard to tune too but that should not cause the problem you are having.

Lloyd

[Injuneer]

Just thought id let every one know ended up changing opti spark whole new car now ....

Hopefully you bought Delco or Delphi this time, rather than the MSD. I'll never understand why a company with the reputation of MSD can't build a simple distributor that is as reliable, or more reliable than the factory unit. How many miles did you have on the MSD?