cleangene

OK, here goes, I have a very good tune which has taken me a long time to get but with a very high lift and lots of duration cam it is very hard to get smooth ride once the TC locks up unless I set the lockup for about 54mph which is about 2k on rpm, this kills gas mileage(9-10mpg city), so I was wondering if I changed the timing around in that rpm area is it possible to get a little smoother ride, or is there another area that I should try. I have tried the TC lock up at different speeds and set the tranie to stay in third for a while longer but that didn't help, way high on rpm. So I was thinking maybe cut my timing back in 1800-2000 rpm range. any ideas other than changing cam.

WS6T3RROR

Add timing don't take it away, make sure its smooth in the area that the surging occurs in.

You can also change the o2 switch mv up to 500 maybe a bit more. It surges because whats happening is actually lean misfires because the cam cant run at stoich in that condition.

Another trick is to move the rpm and map boundaries for closed loop cells to make a cell for that specific condition.

Other than that you can try open loop where you can command air fuel ratio.

A stronger ignition system will also sometimes help to eliminate problems like that as well.

dookie454

your converter being locked is somewhat like a manual trans, so with that said us manual trans guys fight this big time and cant cover it up by leaving the converter open.

You'll find those with unbearable cam surge finally resort to open loop, if that helps then your pretty much have to leave it in open loop unless you can fix your 02's mis-read problem which unless you have a major leak or other problem somewhere, comes back to the 02's not working with big cams.

More timing does help with big cams down low, but there's only so much you can do.