What gap and plug are you running. I'm running a tr4 at .30 which seems to be to big, it's breaking up above 5k. Oh yeah at what point does you plug gap being to tight hurt you, I don't feel like pulling them more than once.

 

That's a pretty small gap. I bet it's some other problem - For instance that plug could be too hot for your application and causing detonation or preignition. But you could have a different problem like valve float or timing, too. And those injectors are on the small side assuming you ditched the FMU.

Stock compression? Intercooling?Valve springs?Tune?

 

I was intercooled on 8psi and stock motor and had to gap down to like .020" until I got a MSD 6A now I'm at .035".

 

Maybe that is his problem, then.

 

im running tr6 at 10+ psi gapped at about .028 and have no ign. problems, but I do run an msd 6a. I would tend to think you're running out of injector, as I too ran 30lb svo's with about 7 psi and they were maxing out. You're running dangerously close to destroying that engine with 30 lb'rs. Also, what timing are you running in the 100 kpa row? Even with all these issues, I would put my money on the optical sensor in the distrib. These things tend to wobble when the bearings start to go bad an cause a loss of signal to the pcm at high rpm. I had it happen to me, swapped out the opti and it was gone. Kept nosing over like you turned the key off at 6k rpm. If you could log the run and graph the opti high and low res pulses you will be able to tell if its dropping out.

 

Well the only reason the 30lb accell's are still in their is because I had a run of bad luck. I was having issues with a cheap opti and just installed a delphi, engine has around 1000k miles on it, with forged 8.9 cr pistons and it is intercooled. I just looked at my old plugs, they were at .028 so I put my new ones at that. I also have the wonderful fmu. I know I'm running 30lb injectors with an fmu but when you put a blower on a car with 100k miles things tend to break. I never really caught up till now with the basic things that need attention.

 

Well, the FMU should be upping the press. then and you might be alright. Do you have a fuel press. gauge on the car? If not you really need to invest in one as well as a wideband. These 2 will help diagnose any driveability situations

 

This thread seems to show the importance once again of why its a good idea if you are thinking about going the FI route to do it right the first time, and not do it at all until you have enough money to do it right, otherwise you'll end up in pro94lt's shoes.

blown 94 is correct, you are not running the appropriate fuel injector size for your setup. That could make your 100,000 mile motor go boom, even with the forged pistons with the lower CR.

You will have to run a bit lower gap before you have issues than you are running now. I am also running a .028 gap with no problems. Make sure you take Kevins advice and you have the appropriate temp range plug also. I think honestly just getting a MSD 6A would probably take care of your break up problems (perhaps without changing the current gap).

Being boosted costs a lot of money. If it doesn't, then you aren't doing it right, and you can expect few times of enjoying the boost, and the majority of the time saving for a rebuild.

 

Well I put the blower on the car around 3 years ago (stock engine) with the inline pump fmu and 30lb injectors. I beat the crap out of it for that time and the only way I drove it was wide open. I hot lapped it over and over at the track last summer on a 98 degree day and a head gasket blew. I had my plugs at .028. Rebuilt the engine and went with the lower cr forged pistons. had my plugs at a little over .030 and thought that's where they needed to be. My car is still breaking up even at .028 . I did one wot run after the gap changed and shut it down. For some reason my lower cr pistons won't work with my 30#ers and fmu. I'm just debating 42's or 60's now.

Call911 I don't think you could sum it up any better. I just thought I was gonna be the lucky one.

 

Honestly you'd be fine with 42# injectors, but 60# injectors would give you more room for making power later.

Get yourself the ignition upgrade you really need (MSD 6A). I think that is the bigger issue why you are breaking up than the difference of .002 gap in your plugs.