PFC tuning issues

[DYI01]

I am having a problem with tuning my PFC. Ive been using the Datalogit to tune and ive gotten my a/f at WOT to just about where i want it, its running about ~14:1 and is pretty flat. I have tuned out knock and the highest it hits is about 35. My problem is thats there is a dip in HP and TQ right at lift engagement. I am using the MWR basemap. I have been playing with the VVT and IGN timings but I cant seem to tune the dip out using my "butt dyno" as i havent been on a dyno since tuning the a/f, and slight tuning of the IGN to to reduce knock. Anyone have any suggestions on how to remedy the situation?

Oh yea... Larryd if you read this I think we should have a ECU tuning forum for questions especially like this, it would be a great resource.

[nyoneway]

Try changing the lift engagement point to affect the powerband dip.

[Illusive]

Originally posted by nyoneway
Try changing the lift engagement point to affect the powerband dip.

NOOOOOO!!!!!!!!!!

dont do that, i tried for about an hour to lower it even 50rpms and got huge drops in power, even after playing iwth the vvt, raising it will just screw up all the vvt maps.

you can NOT but tune the vvt you need to get on a dyno.

that dip we experienced as well and could easily tune out with dyno time, it started to appear when adjusting the vvt settins at column 12 and 13.

depending on what you do you can actually move the engagement further back by just changing the vvt to look almost identical to the stock power curve, which you do not want to do, for the mean time put your vvt maps back to mwr's and wait till you get dyno time to start playing with them.

[monkeywrench]

We spent hours minimizing the dip. The problems are:

1. There's a natural dip there because the cams are not matched well

2. The VVT actuator takes a split second to catch up to the changeover

3. A/F gets a slight blip

You may be able to optimize the tuning for your car and make it slightly better than our map, but ours is going to be pretty damn close.

[bagodoosh]

so how would you explain the dissapearance of the dip in the TPR intake dynos? a similar thing happened with autxr's TRD exhaust dyno: link (http://home.earthlink.net/~celica73/newcelica/dyno.html).

[Illusive]

Originally posted by bagodoosh
so how would you explain the dissapearance of the dip in the TPR intake dynos? a similar thing happened with autxr's TRD exhaust dyno: link (http://home.earthlink.net/~celica73/newcelica/dyno.html).

by dip i think he means that the power curve doesn't continue to rise but instead falls off slightly, but still makes a lil more power, just not at the same rate prior to lift.

-J

[00silverGTS6spd]

Originally posted by bagodoosh
so how would you explain the dissapearance of the dip in the TPR intake dynos? a similar thing happened with autxr's TRD exhaust dyno: link (http://home.earthlink.net/~celica73/newcelica/dyno.html).


you're talking about a totally different tuning setup. nobody knows how the tpr will be affected by the power fc.

[silvercelica2000]

Originally posted by DYI01
I am having a problem with tuning my PFC. Ive been using the Datalogit to tune and ive gotten my a/f at WOT to just about where i want it, its running about ~14:1 and is pretty flat. I have tuned out knock and the highest it hits is about 35. My problem is thats there is a dip in HP and TQ right at lift engagement. I am using the MWR basemap. I have been playing with the VVT and IGN timings but I cant seem to tune the dip out using my "butt dyno" as i havent been on a dyno since tuning the a/f, and slight tuning of the IGN to to reduce knock. Anyone have any suggestions on how to remedy the situation?

Oh yea... Larryd if you read this I think we should have a ECU tuning forum for questions especially like this, it would be a great resource.

try to lean it out at 6000 and slowly rich it back till 8500. I am using PFC and that's what my tunner did.

[Illusive]

Originally posted by silvercelica2000
try to lean it out at 6000 and slowly rich it back till 8500. I am using PFC and that's what my tunner did.

tell your tuner to change the vvt not the base map :gap:

[DYI01]

So basically I should wait till I cant get it back on the dyno and tune VVT to get rid of the dip? I have 2 hours resereved on june 26 so I guess I have to wait till then :)

Any tips on what I should do so I dont dont waste too much time on the wrong things?

[Illusive]

Originally posted by DYI01
So basically I should wait till I cant get it back on the dyno and tune VVT to get rid of the dip? I have 2 hours resereved on june 26 so I guess I have to wait till then :)

Any tips on what I should do so I dont dont waste too much time on the wrong things?

I noticed on the mwrs on my car at least

focus on the colum 12 and 13 not colum 11 which is 5500 rpms

12 and 13 is 6000-6500

try lowering 13 and raising 12,
if that doesn't help go the other way around, there should be a pretty hefty gap in vvt on those columns

once you get that done focus on the 4-5K range, theres a dip in power at 4500 you can tune out with vvt

also focus on the column 16 and 17, you can make about 3-4whp @8600 rpms over the mwr vvt map,

this was all on my car & another team mates cars your experiences will most likely vary due to different set ups ect...

but make sure you clean your maf before you do your dyno runs,

also keep an eye on your knock and do a few pulls in 4th (seems to have the most knock) and adjust your ign accordingly.

-J