What would cause no boost at low mid rpms????

[Royb]

Mine is stick.
How can lag hide in a clutch?

if your clutch is paddle type with non organic material they tend to have a on/off type of engagement & that's there the lag can hide if not dialed in 100%. Mind you I'm picky and very very sesitive to seemingly unnoticable things to the average gear head.

dataloging uncovers these things.

 

[GI Joe]

I think I'm going to make arrangements to see if Jim can get this thing right for me.
Now the next big question.....
The car was dynoed for AF at WOT...even though I dont like the drivability stuff on some issues and I just described this boost issue, should the car be OK to go racing on 3 NOV for WOT stuff?

 

[Royb]

.... should the car be OK to go racing on 3 NOV for WOT stuff?

yes - you won't have a problem due to what you describe. I bet you will set yourself a new record

 

[GI Joe]

yes - you won't have a problem due to what you describe. I bet you will set yourself a new record

just want to make sure that his variable timing stuff wont affect the car at WOT.
The AF was fine on the dyno and it is true that after some work he got control of the A/F. I saw that very clearly and that the A/F was doing what was commanded

One interesting point was that unlike normal race fuel ( leaded) that burns slower and usually makes a little less power, the 109 unleaded ( oxygenated fuel) made 12 hp more without tune changes and A/F went from 11.5 to 12.0 and we retuned it back to 11.5 for the fuel on the race tune...

I just cant afford to hurt this motor...
So what makes it keep the same AF on the street as the dyno because I always thought that under the heavier load of the street the car could lean out...

 

[Royb]

just want to make sure that his variable timing stuff wont affect the car at WOT.
The AF was fine on the dyno and it is true that after some work he got control of the A/F. I saw that very clearly and that the A/F was doing what was commanded

One interesting point was that unlike normal race fuel ( leaded) that burns slower and usually makes a little less power, the 109 unleaded ( oxygenated fuel) made 12 hp more without tune changes and A/F went from 11.5 to 12.0 and we retuned it back to 11.5 for the fuel on the race tune...

I just cant afford to hurt this motor...
So what makes it keep the same AF on the street as the dyno because I always thought that under the heavier load of the street the car could lean out...

there's really very little to change in the VVT tables with stock cams and a blower. the VVT timing tables get lowerd (less spark) the load tables get zeroed out (is that a word LOL) reduced to 0 so they are in effect not used. the cam angel gets moved up some areas and lowered in others.

note about "load" used in tuning circles - it has nothing to do with real world weight of car on road . load is a caculation the cpu uses to determine the amount of air (air charge) passing through the maf. (not weight)

cars can lean out for lots of reasons some tune related and some of the usual environment factors come into play and other hard parts come into play (most often 02's but not limited to just that). if you studdy up on injectors you will find they often overshoot the target and that can cause more fuel and then the o2's try to correct and they can pull too much fuel.

the most serious overlooked item i have seen in tuning is with the knock sensors tables often too much advance is allowed and not enough retard. the most normal overlooked item I see is when the maf is set the rest of the correct tables are not scaled by the same % (up or down)

also most folks dont know if they change the sample rate of the wideband you will see very different results for the a/f ratio. so 11.5 - 12.0 = isn't a big deal - I like 12.5 - 13.1 for A/F on my car for some of my street tunes when I'm just puttering around & when I race with 27 degrees of spark at WOT I run 12.5 a/f most of the time.

 

[ZmanM3]

Hey its hard to say not ever seeing the car if it is belt slip or the VCT or something else.

Our driver is heading down to Texas in a few weeks to move some of my Dads stuff down to his new house. On his way back he will have an empty trailor. Ill see what he wants to pick you up and he can get your car and bring it straight here. We dyno tune it in house, you come up and track test with us and drive it home. The dyno tune session with us will be free, just what ever our driver wants for your lift up. Just an idea??

JimIII

I'll drive my car to you guys myself for a free tune!!

 

[GI Joe]

I'll drive my car to you guys myself for a free tune!!

I think what he meant was " no additional charges"

 

[ZmanM3]

I think what he meant was " no additional charges"

Ha ha, I'd still drive there for a free tune. I've thought of driving there for a dyno tune I pay for.

 

[Royb]

Ha ha, I'd still drive there for a free tune. I've thought of driving there for a dyno tune I pay for.

your really close (240 miles) to one of the better tuners - VPM
http://www.vmptuning.com/store/index.php?

 

[ZmanM3]

I didn't relize that VMP was that close. PMP has to put my new engine in first though.

 

[cheftjpeck]

Vmp Ftw....imo

 

[ZmanM3]

We shall see. PMP were telling me about a very good tuner by them, so we'll see.

 

[Royb]

We shall see. PMP were telling me about a very good tuner by them, so we'll see.

i'm not aware of a top tuner in NC - sure there are tuners there but there's only a small number of "very good tuners" in the public mustang crowd.

 

[JimIII@JDM]

that really doens't matter much - I know there were a few things discovered after a while that do make a difference but not much.

I dont recommend mail order tune from anyone - never will. I do tell people all the time if you are in the area of NJ do go get a dyno tune (if you dont want to learn your self) from JDM SR and if your not in the area ship it to you - (i do have old post on MF saying just that even after I started tunning on my own).

I also recommend tuners (in no order)
Just @ VPM
James @ RWTD
Don @ Lasota

Roy, I know you do your a good man, thank you!

JimIII