How many of you hybrid guys are using a VSS

[TURBOPOWERED68]

How many of you hybrid guys are using a VSS in your cars?
And
Which VSS set up are you using?
Also did you start WITH OUT a VSS then added it your build?
If so How did it affect your car?
Did it improve performance?
Did it improve drivability?
Did it make it easier to tune the car?

 

[S10xGN]

Since my swap already had an electronic dash, I used a Dakota Digital interface box and their trans adapter. With these, I was able to get the 2K pulse for the GN engine and the 4K pulse for the truck's speedometer. All operates "as stock" but can be fine-tuned for tire size, gear change, etc. DL the manuals and have a look.

 

[turbobob924]

I was running without one for 2 years. I just added it and it is not picking up correctly. Reads about 1/2 actual speed.

 

[65malibuss]

I started with the VSS from caspers.
I think it's important since I'm using a turbotweak chip and the chip uses the vss signal to determine ignition timing at wot.
I also find that the mph data acquired in the powerlogger when drag racing is very useful.
I'm even considering getting a large aftermarket speedometer that I can use to know exactly when to shift when drag racing, since the tachometer signal that comes from the buick ecm is not very good.
If you're using a lock up torque converter clutch the vss signal may also be necessary for proper operation, which could improve gas mileage.

 

[22lbChevelle]

Hmm, maybe im missing something but I just screwed in the Chevelle's speedo cable into the 200r4 and went on with my day.. Is there something I should be doing otherwise?

 

[TURBOPOWERED68]

Hmm, maybe im missing something but I just screwed in the Chevelle's speedo cable into the 200r4 and went on with my day.. Is there something I should be doing otherwise?

just that the computer doesn't know how fast the car is going and that the TT features will not work.

 

[22lbChevelle]

Anyone got a pic of this VSS? Where does it hookup? My car has a trans+ w/ extender chip. Any problems with that?

 

[65malibuss]

Normally the speedometer cable connects to the Buick gauge cluster and in addition to controlling the speedometer needle there is a device that sends a signal to the ecm for mph.
I believe the device includes a light, light sensor and spinning window and is located right behind the speedometer gauge.

In hybrids most people use an aftermarket vss sender that screws into the transmission where the speedometer cable screws in place, available from caspers, and a vss converter box, also available from caspers. My vss converter box is hooked up right near the ecm.

You may or may not get better driveability / fuel mileage / performance if this is all hooked up, depending on your chip and whether or not you use a lock up torque converter clutch.

I don't remember exactly what functions are controlled by the ecm that require the vss signal. I would talk to your chip programmer and ask him if your chip needs a vss signal to function properly.

 

[65malibuss]

Caspers link showing VSS sender and converter.

Casper's Electronics, Inc.: Performance Parts

 

[TURBOPOWERED68]

The standard TT chip has 4 areas that can be adjusted individually but if you don't have a VSS signal you will only be able to adjust two of them.

 

[Kovmat]

The standard TT chip has 4 areas that can be adjusted individually but if you don't have a VSS signal you will only be able to adjust two of them.

Do you what the 4 are? And which 2 cannot be adjusted witout a VSS signal?

Thanks,
Matt

 

[TURBOPOWERED68]

1-I think (my instructions are in the garage) First and second gear timing and fuel. As these changes would effect you true all the gears. Because the Computer wouldn't know when the Trans shifts into third and fourth.

2-again I think- third and fourth gear timing and fuel would not work at all because the computer wouldn’t know when the car is in third or fourth

 

[Blazer406]

I realize this is an older thread... but not sure anyone needs any help still or not.

IMHO... the 1st and 2nd gear fuel or timing..... and 3rd and 4th gear fuel and timing.... is triggered off the (3rd and 4th gear) switches inside the transmission.... that send a ground or open signal back to the ECM so it knows what gear you are in....

As far as adjustments.... timing on an extender chip (per turbobob) is not controlled by the VSS.... but the switches. Torque converter lockup speed IS. Also some defueling is also triggered off the VSS when the throttle is closed quickly... (also per turbobob).

I'm not sure on the TT chips... but I am fairly sure he also triggers timing changes and fueling changes based on the gear switches in the tranny... and the TPS sensor of course...

I hope this helps?

 

[TURBOPOWERED68]

I realize this is an older thread... but not sure anyone needs any help still or not.

IMHO... the 1st and 2nd gear fuel or timing..... and 3rd and 4th gear fuel and timing.... is triggered off the (3rd and 4th gear) switches inside the transmission.... that send a ground or open signal back to the ECM so it knows what gear you are in....

As far as adjustments.... timing on an extender chip (per turbobob) is not controlled by the VSS.... but the switches. Torque converter lockup speed IS. Also some defueling is also triggered off the VSS when the throttle is closed quickly... (also per turbobob).

I'm not sure on the TT chips... but I am fairly sure he also triggers timing changes and fueling changes based on the gear switches in the tranny... and the TPS sensor of course...

I hope this helps?

I don't remember the thread but Eric him self said to me that his chips USE the VSS and nothing else. I also specifically asked him about using the Trans third gear switch and he said that it was not possible with his chips.
BUT
This was a few months back so who knows if he made some changes by now?

 

[Blazer406]

That is interesting.... I have quizzed TurboBob on his chips....because a customer was running one of his chips... and has a T350 tranny now...

I had assumed Eric's chips also triggered timing changes based on what gear the tranny was in...I guess you should never assume anything when it comes to these cars....

It makes sense however... because I am fairly certain... on one guys car I was helping (TT chip) ... that I saw a split in timing between 1st gear and 2nd gear... of about 1 degree.... then a 2 degree split between 2nd and high... since there is no way with the switches in the tranny that the ECM can detect if you are in 1st gear or 2nd gear..... the VSS would have to be used to make some sort of timing split like I witnessed on a DS log.