dyno graph analysis help

[phillysrt4]

Hello everyone!

My mods are stage 2 with toys, mopar cai, mopar bov, and mopar exhaust. When I had this setup dyno'd before, the WGA wasn't set with preload (don't ask), so my curve was a little different. Plus I had to narrow my plugs from 48 (dont ask) to 37 to keep the AF under 12.

I got the WGA adjusted with the proper preload per the instructions to the kit. As you can see by this graph, there are many sags and surges in the torque curve. These are in line with when the boost would rise and fall. It would surge to 18+ then fall to maybe 13. It would continue to oscillate, although not as dramatically, until about 4800 where it would rise and hold with the slow fade to redline. Also I notice that the AF is VERY lean compared to when the WGA had no preload on it.

My two pressing questions:
1) boost leak?
edit - vacum lines are zip tied, but i havent done a pressure test.

2) Narrowing the gap helped richen it before. Will narrowing the gap now that the WGA is set correctly also help flatten the torque curve by making it run a little richer, hence the PCM wont pull boost assuming (1) is not present?

Thanks in advance for ideas. I'm just trying to get a handle on this and not waste time testing for leaks if its as simple as resetting the PCM or regapping my plugs.

http://i10.photobucket.com/albums/a132/phillysrt4/dynorun_hom_on.jpg

[SPECJ]

Most likely the boost leak is comming from the MOPAR BOV. The oscillation of the boost gauge is a definate sign of a leak as well. Pressure test it, fix it and you shouuld def see the powerband smooth out.

Yes, lowering the gap will help control the A/F's slightly, but by lowering the gap you are actually firing less of a spark into the cylinder. The ideal gap on a plug is just high enough to not get any hesitation. Gap the plugs at 35 and you should be good.

[phillysrt4]

Thanks for the input. The BOV noise is getting annoying as hell, so I might just go back to stock configuration.

I'll leak test it when I have time this week

-D

[N2MB]

you may just want to try putting the stock surge valve back on and see if it resloves your issues.out of curiosity maybe you put the bov on wrong?

[phillysrt4]

Hmm.. definately things to check. Thanks for the input. I'll try to get it done this week and see what happens.

edit - have you had others put the stock surge valve on and had this problem resolve?

[ptperformance]

Looks like a boost leak. Try getting on the dyno and run with a lower pressure like 15 psi and turn it up till you see the wave in the run. If it is there at lower pressures I would have to say boost leak or your knock sensor is loose causing pulled timing.

[phillysrt4]

turns out I got pwned by a boost leak thanks to the mopar rice valve and a loose worm clamp.

both have been resolved and boost holds much better now.

Probably gonna run a dyno and see what happens.

-D