Tcm tune defuel issues

[DMAX497]

What is y'all's opinion on a TCM tune?

Have a LBZ with a suncoast Trans w/ 1056.

My truck on the stock tune clicks off shift at WOT throttle in 2wd and 4wd. When I turn up the power to my race tune and #4 tune it falls on it's face. The 1-2 shift is the worst just launches hard then falls off then picks back up and shifts good but still defueling. I did a taps reset with EFI but still need to get a tech 2 and a quick learn done w/ taps reset. Fuel starts coming out about 3300 rpm. We made it to rev out to 3500... Thy helped a little bit.

I have Ben's lock up box that can be delayed what have you. Should I manual lock it in first gear or?

Or do I need a Tcm tune to raise my shift points? My tuner I'm sure will figure it out. But wondering if I should ask for a Tcm tune? I've searched and read and read with no real Answers. I guess logging and testing we
Will figure it out

 

[hondarider552]

I think their overrated. My tcm tune is 100% stock only change is wot shift rpm is 3750rpm. Shifts good enough to go 10.60's. granted I only use mine for mainly track use and wot, so part throttle shifting isn't a much of a concern for me.

 

[DMAX497]

I think their overrated. My tcm tune is 100% stock only change is wot shift rpm is 3750rpm. Shifts good enough to go 10.60's. granted I only use mine for mainly track use and wot, so part throttle shifting isn't a much of a concern for me.

So maybe that's what I need because part throttle feels fine? I'm no expert with EFI I can do "some" things.

 

[hondarider552]

If your having shift defuel issues the problem is in the ECM not the tcm, tcm only requests the defuel, ECM has the actual numbers.

 

[CaptPhil]

I was having bad defuel, especially on the 1-2 shift. Raising that shift to 3700rpm fixed it completely. You have to make sure you have your fuel out far enough and that the ecm defuel table allows you to go that far.

Sent from my SGH-M919 using Tapatalk

 

[DMAX497]

So you raised it they far but does your truck actually shift at 3700?

I guess we need to go up another 200 rpm on mine because it's must be hitting a limiter for defueling.

 

[LWATSON]

I'm shifting at around 3800 and it shifts really good. Also you've definitely got the air for 4000 rpms.

 

[quinton]

Raise your shift points and see what that does. Double check your ECM tune because, like stated above, that's where defuel comes from.

 

[DMAX497]

Should I worry about studding the heads at the 3500rpm and above mark? 79k miles on the truck. 6-7 with twins on etc. Was stock before that.

 

[MMLMM]

The issue is in the ECM tune. You notice more of a drop (fall on face) because your commanding a lot more fuel and then pulling it back on shift and it feels rough. Clean it up in the ECM tune first. Smooth out where its de-fueling, Then if you need to adjust shifts for particular turbo/fuel setup, hit the TCM tune. A good log will make this quick and easy work for you.

EDIT: you should have worried about studding the heads when you put the twin setup on the truck lol

 

[DMAX497]

The issue is in the ECM tune. You notice more of a drop (fall on face) because your commanding a lot more fuel and then pulling it back on shift and it feels rough. Clean it up in the ECM tune first. Smooth out where its de-fueling, Then if you need to adjust shifts for particular turbo/fuel setup, hit the TCM tune. A good log will make this quick and easy work for you.

EDIT: you should have worried about studding the heads when you put the twin setup on the truck lol

I figure if it's gonna pop a head gasket I'm going to Throw a motor in.

Sorry about these newb questions, but y'all are way more knowledgable over here. Thanks for
Your input.

 

[03spoolindmax]

I had the same problem with my lb7. It would fall on it's face on the 1-2 shift. I figured it was the trans since I had built it myself. I sold the truck so I never got to dig into it. My lly does the same thing on a completely stock tune though.

 

[DPC]

I had the same problem with my lb7. It would fall on it's face on the 1-2 shift. I figured it was the trans since I had built it myself. I sold the truck so I never got to dig into it. My lly does the same thing on a completely stock tune though.

On a LB7 you need to adjust the engine torque tables.

 

[paint94979]

I think their overrated. My tcm tune is 100% stock only change is wot shift rpm is 3750rpm. Shifts good enough to go 10.60's. granted I only use mine for mainly track use and wot, so part throttle shifting isn't a much of a concern for me.

Brian I must disagree. My experience with TCM tuning has proved it critical in good ET. 12.1 vs. 11.8. My TCM tune is very much modified which enabled me lockup in 2nd.

 

[03spoolindmax]

On a LB7 you need to adjust the engine torque tables.

I didn't tune it. Dmax tuner did. They will not be tuning my new truck.

 

[hondarider552]

Brian I must disagree. My experience with TCM tuning has proved it critical in good ET. 12.1 vs. 11.8. My TCM tune is very much modified which enabled me lockup in 2nd.

I don't have a fancy lockup box, if I did I may think differently :roflmao:

 

[quinton]

Brian I must disagree. My experience with TCM tuning has proved it critical in good ET. 12.1 vs. 11.8. My TCM tune is very much modified which enabled me lockup in 2nd.

How are you having lockup in 2nd? Thought for the 5 speeds tables weren't coming until April?

 

[Cknight199]

Subd.

 

[DMAX497]

Now we are getting some good input here. Who's runs a lock up box and doesnt? Truck seems to shift "better " at WOT without it in auto mode. Bens lock up box.

 

[mike diesel]

5 speed lockup tables are coming out in april? Now I'm deffinately getting a tcm tune when there available.