Completed Project Top Mount TURBO Explorer V8

[RegionThr33]

Been doing some logging and this started happening at wot. The arrow and red vertical line is at the 1-2 shift(5536rpm). It looks to me like the tps is bad but it voltage tests good.
Any ideas?

View attachment 161519

 

[RegionThr33]

Red= engine speed
Purple= Spark
Green= vehicle speed
Blue = throttle position

Throttle position goes crazy(pedal to floor) at 1-2 shift.(red vertical line)

 

[vroomzoomboom]

yea, you have something funny going on there. try two things. with the key on engine off check your voltage at the tps using your hand to open the throttle at the trottlebody, then do the same having someone press on the peddle and see if there are any differences. on your log that should be a flat line

 

[Dono]

Yup, throttle position sensor or wiring. If I remember, you have one front am ls?

 

[RegionThr33]

yea, you have something funny going on there. try two things. with the key on engine off check your voltage at the tps using your hand to open the throttle at the trottlebody, then do the same having someone press on the peddle and see if there are any differences. on your log that should be a flat line

Yeah. I did exactly that. Everything seems

yea, you have something funny going on there. try two things. with the key on engine off check your voltage at the tps using your hand to open the throttle at the trottlebody, then do the same having someone press on the peddle and see if there are any differences. on your log that should be a flat line

Yep. Checked voltage both ways and it worked fine but as soon as I moved the wires, it dropped down to .54v from 4.75v
I'll be soldering everything tonight. I've put it off for too long already.

 

[RegionThr33]

Yup, throttle position sensor or wiring. If I remember, you have one front am ls?

It was the wiring. Yes. It is a GM tps. I just need to solder everything and finish my harness.
Thanks.

 

[RegionThr33]

To be more clear about the voltage reading. It reads from .97v-4.75v at wot.

 

[RegionThr33]

Much better(TPS is dark blue) . But look at that long 1-2 shift. Its starting at the 13sec mark and finally shifting at 14.5sec. (red line is rpm) not sure if its the trans or lack of traction.

 

[vroomzoomboom]

if you have something to log wheel speed, put it in there and go for another run. it will tell you which one it is. however, if you have the original trans in it with no shift kit, you may know the answer already.

 

[RegionThr33]

if you have something to log wheel speed, put it in there and go for another run. it will tell you which one it is. however, if you have the original trans in it with no shift kit, you may know the answer already.

Yeah.thats what im afraid of. Im gonna take it out tomorrow to check again. The green line is vehicle speed. It jumps around at the same time as the shift. Not sure if that is reading from wheel speed or not. The yellow line is load. Looks like it drops a little at the same point.

 

[Dono]

Can you up your shift pressures for 1-2 shift at something like anything over a tps reading of 700?

 

[gmanpaint]

 

[RegionThr33]

Can you up your shift pressures for 1-2 shift at something like anything over a tps reading of 700?

Torrie said that he put as much pressure there as he could. I adjusted the gain on my boost controller to ramp up the boost at higher rpm (it was falling down to 5psi or less) and got it to stay at 6.5-7psi. After that it definitely feels like wheel spin. I didnt have my laptop with me but I'll log it today.

 

[Turdle]

I agree the green line ( VSS?) fluctuating at the shift point shows wheel spin.

 

[RegionThr33]

Definitely wheel spin. One of my friends just stuck his phone out the window and filmed it. Its worse now too. I ramped up the gain to keep 7psi in higher rpm and it definitely made it spin more.

 

[RegionThr33]

Heres a pic of the log.
Red line is rpm
Green is vehicle speed

 

[RegionThr33]

Didn't realize I didn't update you guys here.
My transmission is dead. Dumping fluid from the bellhousing and is constantly in forward gear and whatever gear I select. I was hoping that I just blew the pump gasket allowing fluid to be constantly pumped into the forward circuit. I think I Welded my forward clutches though. I haven't pulled it out yet.

 

[Dono]

I think your right, drop the trans and go thru it.
It's possible that the only thing that's wrong is that front pump seal, but if the trans is out anyway....

 

[RegionThr33]

I think your right, drop the trans and go thru it.
It's possible that the only thing that's wrong is that front pump seal, but if the trans is out anyway....

Precisely. I've already found everything I'm going to build it with. It sucks though, I won't be able to buy a good stall converter like I wanted to. Going with a 2500 stall from Monster. With having to buy everything else, I just won't have the funds for a good quality one.

 

[Dono]

If its a single disk lockup converter, make sure you tune out lockup at wot.
Also, tune out the OD shift (4th) at wot. This one can be difficult as for some reason the pcm doesn't necessarily respond like we think it should after tuning. Vroomzoomboom ran in to this.

Those are the only words of wisdom I have on the torque converter.

Its all about how much money we can throw at our stuff, even then there are no guarantees.