ive got my 6port turbo running and all, but she has a big miss in it. no aux sleeves, so its like a big extended port. that being the case i had some bdc extended port ideas about what i was dealing with. ive tuned my afrs at idle to about 13.0, but still get this missfire. i did some reading in this section, and saw a nice thread about people with big ports running much more advance in vacuum than i am. im gonna post a grab of an advance map i just altered based on my reading( mind you, this is advance from -5*, so 10 is really 5, i think). i think this might be a reason im missing so hard. any suggestions, or comments? i also just readjusted my split too. from 5 across the board in vacuum to 12 across the rpms at 15psi.

oh yeah, its high compression s4 rotors too.

 

um im using 93 octane too

 

i guess i must have asked a stupid question. figured id atleast get flamed or something.

well today i adjusted the map back down a little in the low rpms/idle vacuum area back to about bdc's extended map. started it and just like yesterday a miss. but today i replaced the plugs first. but it was still missing so i kicked up the advance as much as 5*more and even 5* less. with no change. id say at best the advance was 27* advanced.

figured id update incase anyone was interested.

 

Try leaning it out at idle. While it should idle at 13.0 pretty well, try going even leaner. On an old FC of mine, I ran it at 14.7 at idle. CJ

 

when i was messing with the fuel before trying to lean it out to 13.0, i made too big a step a couple times and saw like 14.0-15.0 range. it ran and didnt knock or anything. but the way it ran def changed. was afraid to rev it to see response.

 

I don't know what kind of EMS you're running, but you should be able to tune just the idle. Is the miss through out the different RPMs? CJ

 

ive only reved up to about 4000 cuz it starts to get leaner. but this is only in 40-60kpa range. medium vacuum id say. and i was too worried to think about whether it was missing by that point. but i know it is def less noticable as i rev up. given the afr leans out as i do rev. so it seems justified. and im megasquirt'n with a 16x16 map. so yeah i really have only tuned in the less than 2000 rpm area and high vacuum. like i said, i just been worried about going leaner. mostly been at 11.5:1 and have gone to 13.0 for a while.

 

Under light load you shouldn't be worried about detonation. With a n/a FC, it made peak power at a 14.2-1 a/f ratio.....so as long as you're not into boost, I would'nt worry about it going to lean. But it sounds like you need to have someone tune it for you, imop. Good luck, CJ

 

well this is my first standalone... so its a learning experience. but yeah. having someone to help would be nice but, there isnt really anyone around here to do that. i live in delaware and i dont think there is a registered 7 owner within a hundred miles of where i live. in any direction. so im limited. there is a dyno about 15 minutes down the road. but if i pop my load, ill just rebuild it. its a 50000 mile engine anyway.. so no big loss. but thanks for the help. i had figured it was a mix issue last night right before you responded. and that just confirmed it. but seriously, thanks for the info.