4CN Air

iTrader: (7)

I'm getting a a sort of surging or stumbling, not sure how to describe it, below 3000rpms. I've played around with the acceleration map but it doesn't seem to help no matter which way i go with it. Also it doesn't do this when cold, only once the water temps get up to normal.

I had Dave at KDR tune it just recently (BTW: 410whp @ 16psi on 93 octane in 3rd gear without the boost controller (another story)). It runs great at WOT and anywhere above 3000rpm, but it's a pain around town. Any ideas?

Based on the mods in my sig what should my Accel settings be? I know the Accel map is just for fine tuning and I doubt it's what is causing this problem, but based on the rpm and throttle range it's affecting maybe it is?

Another thing, I was running way too much premix when I took it to KDR, so I pulled the plugs and cleaned them. Didn't fix it. Could I have clogged my injectors or fuel filter with all the extra premis? Also the surging is caused by a rich condition correct?

My o2 feedback is turned off, so this is not the problem.

Thanks for the help,
Cody

jd to rescue

iTrader: (3)

You may want to check the ISC at the backside of the UIM. If it is hanging open due to debris, etc., it will cause the engine to surge. Had a piece of gasket pass into mine one time and caused it to hang open. Was a real pain to deal with 'til I figured it out.

dubulup

sounds like you fuel correction coolant temp map is a little off...

probably nice and rich when its cold, but when the car warms up...your car is running lean in vac.

nice #'s

4CN Air

iTrader: (7)

the numbers should be a little better. My wastegate was not working properly. I found out when i got home that there was carbon built up on the shaft from it sitting for a while. It has a 9psi spring in it but was acting more like a 16psi spring on the dyno, so we ran it without the Profec hooked up, which KILLED the spool up. In 4th gear with the boost controller 425whp would have been a given. I was happy with the health of the engine and turbo though. I also found out how much time and money went into this engine (thanks Zack K). Everything is cryo'd and the gas porting KDR did kept it from dropping off in the high RPMs.

Dave also fixed the driveability, so much that it is more streetable now than with an RX7Store "tune" with stock twins! I won't get into my RX7Store rant right now, simply because I enjoy cheap parts and an online forum too much. I guess it just took me some time and money to realize what they are good for and where they lack.




So it's def. lean with those symptoms? I went into the PIM settings and enriched 1000-3000rpm settings a little at a time the whole way up to 110% with no apparent effect.

Also my ISC is long gone.

She's tuned and runs great but around town it makes it seem like either a.) I can't drive, or b.) I'm driving a piece of junk

jd to rescue

iTrader: (3)

I had a feeling after I posted that may be the case by your mods.

4CN Air

iTrader: (7)

Pretty please help me

Red Suns

Free bump. Oh and thanks for the engine mount Cody!

dubulup

did you try to add fuel in the low rpm vac areas? No dice?

4CN Air

iTrader: (7)

yeah I tried adding fuel to light load setting via the left hand column for water correction at 80+. Then I went in and selected all the vacuum cells from 1000-4000rpm and put more fuel in them, nothing. So then i took my base map, threw it in excel, and did some extensive smoothing. Power delivery is smoother but I still have the problem down low.

Attached is my base map along with the graph.

I'm thinking it may be an ignition problem, so I changed my BR_EIX leading plugs (after hearing about problems with them) for stock BUR9EQ's. No change. If anyoen would be willing to open my dat fiel and do a little analysis I'd very mcuh appreciate it.

Thanks for any help you guys can provide.

4CN Air

iTrader: (7)

UPDATE: discovered the surging problem!

(my spark plug end at L1 connection beside a good one)