Well Since I took out my cat it free'ed up some back pressure and now I am able to hit 8psi when I changed my external wastegate. After I go past 6 psi say 6.5 around 5500 RPMS or there about it starts to sputter/misfire, I am burning full rich and EGT's are normal, my plugs are 2 ranges colder, no CEL's and timing retarded 0.5 deg per psi with my BTM. I don't apperar to have any vacum leaks that I know of. checked plugs and are normal tan color.
Any suggestions on what is causing this?

 

My setup does the same thing only under full throttle.
It "pops" because I am running it a little too rich. If I lean it out a bit it becomes a whole lot faster.

 

usually engines "pop" when they're runing lean and buck when they're running rich... but i guess if you have an air/fuel gauge you must be running rich...

 

Turn your BTM down to 0 and see if it goes away..

Jeff

 

I did turn it all the way down, but I was starting to hear other wired noises maybe pinging, but the pops did not entirely go away, I am gonna try regapping my plugs to .035 from .044 and see if that works.
Also when it does misfire it is at full or close to full throttle, and when it pops my A/G goes totally lean and comes back to rich again. The car does not buck or anything like that, I am leaning towards spark as the problem, but I guess i have to start somewheres.

Thanks

Mike

 

well I think I may have figured it out, my a/f guage is so in accurate, after I gapped the plugs to .032" it ran a little better. I had a hunch that I was leaning out so I tryed a friends A/F guage and once we hooked it up it was so evident, I was leaning out when I was at full throttle, My FMU is djustable luckly and i adjusted it to the max it could go which is probly 7:1 or so (6:1 disc) and I am good till about 8ish PSI and it starts to lean out again and sputter , I am going to change back to my lebaron wastegate (5.5psi) and run about 6-7 just to be safe. Once I ged bored with this turbo and get a bigger one I will get a hondata.

 

good thing u figured that out now, or i couldve been bye bye engine....

 

what plugs are you using i run ngk 3330's aka bcpr7es @ tehir stock .32 gap and 14psi and no popping hwat so ever

 

I am running NGK ZFR7F-11, and the popping is gone, I was hitting almost 10 psi yesterday and no popping was fuel problem, luckily I caught it, even though I got a spare engine still would hae made uneccessary work.