Ok I have a ls2 with a tc78 and it runs great, traps 113 in the 1/8th blah blah. But tonight I was playing with my boost controller and 2 step to get ready for the track tomorw night all was well, I madea few passes on the road out front and everything was dandy then on the way home I rolled into boost and it felt like a cylinder is dead.. I hve great ful pressure at the rail, and no blow by at idle. It runs great part throttle just anytime I get into about 0 lbs of boost it stumbles. I have tr6's (about 100 miles old but I know that doesn't matter),great supporting mods like double springs,e85,80lb injectors running 100psi at 12lbs boost,runnin off 11_12lbs wastegate right now. My boost controller didn't want to work.

I'm thinking while I was in the shop playing with my two step I Fouled a plug to two. But would a foul plug run good on idle and part throttle? Ugh I work till 5 tomorow and I was surpost to be at the track at 7 so I'm stressin out right now. Ill pull plugs once I'm. Off tomorow but I would like some experience people to tell me what they think.

 

I can't see a injector being messed up and only making it miss up top? Wouldn't it miss at idle if that was the deal? I dunno I still think a plugs fouled andboost is blowing it out.(hopefully)

 

I would put a new set of plugs in it first and try it out. Alot of ignition problems show up under a load when they are not present at cruise or idle.

 

I had this happen spraying nitrous. It turned out it was a cracked spark plug(porcelain was cracked). Acted totally fine until you sprayed it. Don't know if this is any help.

 

Spark blowout is a common problem with E85, and if everything is fine including the plugs and heat range (don't go too cold) then try closing your plug gap. What's your current gap?

 

Ok cool plugs it is. Since I'm on e85 I've heard that fuel lines break down sometimes so maybe I have some junk sitting on top of my injectors. So ill pull them and shoot some brake clean and shop air in them. Hopefully that'll do it! I got a lot on the line tomorow ! I got'ta make it to the track!

 

Have you checked for any boost leaks?

 

Boost leaks? Well no I haven't but it spools right up to wastegate pressure. It just pops and farts alots

 

What is the air fuel doing when all this is happening?

 

+1 for new plugs or regaping the ones you have.

 

+2 for new plugs, gapped at .025-.028. Also look at your plug wires real close....

 

I bet it's a plug wire.

 

No, however all the junk building up on your tank walls from gasoline in your tank for years before switching to E85 can be cleaned loose by E85. But if your fuel filter works worth its salt then it will have kept your injectors clean. If you went lean on boost from a clogged filter, then you would probably be out an engine. So it's probably ignition/spark. GL.

 

Cool plugs on E85 is not always a good thing....

 

Did the plugs end up being fouled?

 

Sorry I just seen this but yes it was the plugs. I kinda have a problem though my drivers sde bank is richer then the pass. Th drivers plugs are dark and the passengers is creamie. That'll be to figure out for anothr day.

 

We had a car come in like that and it turns out that the previous shop had shaved one side heads more than the other We had to have the other side milled down and things were fine after that. Only issue we have now is his supercharger belt is slipping over 4500 rpms

 

Ive went through two sets of TR6's in 5,000 miles. Single turbo 6.0 on E85 gapped at .024. Switched to Autolite 103's. So far so good.
Same symtoms at you when they went bad.