So i've been dealing with a problem ever since i had the WEB 546/547 cams installed on my 1g.

I'm running on evo 9 fuel pump (non-rewired) and 560cc injectors, stock intake. B16G @ 20psi.

Tuning with AEM UEGO Wideband, AFC Neo, Logger with mmcd.

After installing the cams, i took a bit to set my low fuel trim settings on the afc.

After that it was time for WOT pulls for the high settings on the afc.

i cant seem to get the 3k rpm range to lean out even after maxing out (-50) the afc setting for that rpm.

But that's not the main problem i'm concerned about; the bigger problem is stuttering while accelerating @ WOT.

If i'm cruising, lets say...on the freeway, 4th gear, around 4000rpm, and i WOT, the car will stutter while building boost UNTIL it hits full boost, and then it'll pull hard and accelerate normally.

AFR's are usually at 10:1 and i've tried leaning them out somewhat so while building boost it isn't so rich, but once it hits full boost, it'll be really lean, so i end up richening it up again to avoid being too lean at full boost.

Last night i changed my spark plugs with BPR7ES gapped at .028 since i figured my old spark plugs were fouled from running rich for months. The wires seem to be in good condition. (ngk as well)

it helped a little but but not too noticeable of a change.

once again, the stuttering only happens while BUILDING boost, not while at full boost.

This was never an issue before the cams install.

Have not done a boost leak test yet, but as stated above, never happened before the cams install.

what suggestions would you guys have as to what else to look for?




(dont gimme talk about "get link" or "get ostrich" because it's better tuning tools... i know they are, i'll be upgrading in the future, but for now i'm working with what i got)

Well erix something like this happened to me when I had my old motor I don't know how much of a help this can be but maybe timing is off or something it turned out to be that on mine. Since you said everything was good before the cam install the only obvious things that were moved was timing and your cams right.

could be a possibility wally, i'll probably check that asap.

after reading through thread in dsmtalk.com,

they didn't have the same problem as me, but suggested checking for things like:

timing
boost leaks
plugs/wires
coilpack
mas
etc.

i'ma check out timing and boost leak tests asap and switch my mas with another stock mas and see if it helps.

O2 sensors?

WOT 02 sensor input is ignored by the ECU. What are your TH points on your AFC looking like? The AFC blends Lo and Hi settings between when your throttle input is higher than the Lo Th point but lower than the Hi Th point. Also, don't mistaken misfire lean read outs for actually being lean. O2 sensors (wideband or narrow) read oxygen. If you misfire, it will show up on the wideband as lean due to oxygen not being burned, and in the exhaust system.

Also could be gap too wide. Dont know what turbo you are running but usually, the misfire will happen when the plug is under load. The 14B and 16G will spike boost and taper, that missing could be when the boost hits max, and the missing goes away in the higher RPM due to boost tapering low enough that the plug doesnt miss.

It's a guide not a rule. I run .020" Also consider that the gap get bigger as it gets hot. Set Th points to 30 65.

Just try it erix sam that the RRE thing was more like a guide not a rule. It doesnt hurt to help and it actually might be your problem.

Try .024. It will probably open up to .025~.026 after a week or so.

Oh damn i'm trippin erix haha I said that all wrong I meant it could actually be your whole problem you never know. Erix since im buying spark plugs tomorrow Im buying the feeler gauge as well I can stop by your house and we can do it there. Or at the meet spot which ever one is cool with you.

Alright then cool I get out from work at 1. So around 2 im going to go by the stuff and then head out to your house if your there. I'll hit you up before I leave tho.