Ok, Im building a TPI small block to go in a rock buggy

my question is how freeked out will the ecm be not seeing a VSS signal

I could put a sensor on my transfercase but mostly it would see rpm after a 5.14 reduction (on top of th400 ratios)

Have any of you seen or herd of a fix or work around?

What is the general consensus of whats gonna happen, because at first thought rock buggys dont go fast... but tell that to the guys bombing across the Cal desert at 100+

I want to be able to tune in a good running engine with better throttle response than the ls1's Ive seen running the stand alone ecm

so Im wondering......

Thanks

Jason

 

I just wrote a post about the VSS in my car and using the highway spark, you can make a TPI engine run fine without it, it does control some features you'll have to work around but for what you're doing with it I don't think you'll ever really miss it. When my car was a weekend only track vehicle I never ran the VSS and this was before I was into prom tuning, you can get away with it; but for future reference, don't be so scared to ask questions, you didn't break any rules why would you be banned?

 

technically not third gen related but no reason to be banned the thread would just be closed

 

It's about a motor that was put in third gens....so....in a round a bout way still related

 

thats why i said technically

 

Off topic:

There are plenty of us here that don'e have thirdgens, or even own parts that would be used in thirdgens, except for the ECM itself. My current ride is a 1973 Datsun 240Z with a turbo 2.8L inline 6 cyl, running a '7749 and code59, actually not even that ECM nor code would have been available in a thirdgen. The DIY PROM forum isn't spcific to the third gen, just to tuning the code in the ECM, there doesn't seem to be a requirment to own or use third gen parts to be in this forum.

On topic:
Currently in the same 1973 Datsun that I listed above I am not running a VSS, though I will be adding one soon. I am working on retrofitting an Optical VSS, if that doesn't work I'll go back to my original plan of a differential mounted reluctor wheel and magnetic sensor.

There are some things that get effected by the VSS even at low speed, such as idle flags, DFCO, and others. You can tune around that, but with the difference in RPM and wheel speed, due to the short gears you'll be using the ECM will likely throw a VSS code, mine did until I turned it off.
In many bins you can adjust the VSS parameters to read correctly.

 

mostly just poking fun at myself

I have any trouble following a forums rules, have any fear of being banned the is full of info, its just that there is usually a line some people want crossed in what they feel is there world. There is tons of info here, it just seems the OT questions I have in a thread 29 pages long, and is in post 39 which is one line....

for the help, mainly because every one here could just say jump off a cliff....

I was registered here in 2003 and had a very good plan as to what I needed to do, but so much has advanced so far since I have to

 

Check out my thread on putting a VSS in a Jerico: https://www.thirdgen.org/forums/diy-...ico-trans.html

Car ran without it, but I was having tunning and driveability issues, so I finally put one in. Just got it working today, and I'm glad I did it. Tunning issues are still there but I'm making steps in the right direction.

What kind of T-case? Jagsthatrun.com might have what you need if it is a GM t-case.

 

the T case is a Stak 2 speed 5.44 http://stak4x4.com/

from there site

Vehicle Speed Sensor

Our VSS is a factory Jeep Rubicon sending unit. It is a direct plug in to 2003-2006 Jeep Wranglers and is easily adapted to the 1997-2002 Wranglers. If your application utilizes a mechanical drive speedometer, then you will need to replace your factory speedometer with an aftermarket unit like the ones from Auto Meter or Dakota Digital. Our VSS sends three pulses per revolution of the rear output shaft. If you need a different signal or pulse count, there are several aftermarket “signal convertors” available.

 

I want to see a picture !!

 

lots of people here without thirdgen's. I've had a few, but currently have a big block powered 50GMC, 91 S-10 with an iron duke, and an S-10 blazer with a 2.8. Also working on 38ford street rod with a TPI and another early 50's chevy pickup with a single plane EFI. All of which currently are or will be controlled with 730,727 and 427 computers.

This site is the #1 best place on the internet for learning about working with the OBD1 GM computers!
On the other forums I visit, such as the team chevelle site (best place for big block chevy knoweledge) I frequently refer people to this site for EFI info.