I have a S5 TII with a mild street port and hybrid stage 2 turbo, RB 3in full cat backk, haltech E8. about 300hp

I had issues with light driving and the Stock TPS & throttle body.

I have gone to the Haltech TPS. and installed it and made a bracket to mount it on and replace the stock TPS.

I am still have issues with the light driving.

This is due to the talking with multiple vendors and that Haltech's quality of TPS is not that good.

I can not find another TPS in the market that is a D shaft type.

In finding this I have been thinking about replacing the whole throttle body with a single plate design.

I have found the following
a Honda throttle body @ 70mm
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/custom-intake-manifold-honda-throttle-body-859181/

an Infinity Q54 @ 90mm (lower down)
https://www.rx7club.com/defined-autoworks-176/single-90mm-throttle-body-mod-3-rotor-843220/

Edelbrock
VICTOR RACING THROTTLE BODIES 70mm or 75mm
ADAPTERS or PRO-FLO XT THROTTLE BODIES 90mm
http://www.edelbrock.com/automotive_...niversal.shtml

I know smaller is better to low end drive ability.

So I am thinking of going with the 75mm.

1. Anybody done this before?
2. How is the low end driving?
3. Issues you have had?

 

are you sure it's your tps causing all the problems?

 

Doesn't Bosch make a D type TPS? Try searching for a "throttle angle sensor", which is another name for a TPS. I think the Motec catalog has some.

 

On my 1st gen, for my Megasquirt I used a stock tb but modified the main shaft end so that I could use a Mustang tps. Works great.

 

when you say you have "problems with light driving" how do you know it's not just a problem with your accel enrichment tuning? The whole purpose of a 3 bore, two stage throttlebody is to improve driveability under light loads. Is the engine going lean from slight throttle movements?

It can be extremely difficult to get a standalone to drive like stock under low load. It's far harder than WOT tuning, and at least as difficult as idle tuning. I suspect this is a tuning issue as long as everything was installed correctly.

 

When watching the logging, I see the TPS spike down and then back to the throttle point , yet the throttle is in the same position.
This is only in the lower end of the TPS range (less then 20% TPS).

I will try and post a screen shot. So you all can have a better idea of what is going on. With annotation.

 

I had the car tuned by good Auz. tuner. So i do not want to mess with the maps much.
What wold be the "accel enrichment tuning" map on a haltech?

it was going lean on slight movements but that got fixed when i set the "throttle Pump" setting to a default base maps settings.
it is feeling much netter since that but I can not get the car to get a steady low rpm drive.
It seems it always wants to accelerate and go faster. So i am either on if off the throttle ans not @ a constant input.

 

throttle pump is another term for accel enrichments, it depends on what software you are using.

sounds like electrical noise due to a grounding or shielding issue. it depends how bad it is really.

 

the red lines are relative to my foot on the throttle.

See how it spikes?

 

Try swapping to another TPS of the same style.

 

what tool are you using for the tps mapping? i like to use my snap on vantage pro, it looks to me like you are using a laptop connected to the ecu?
and WOW, that tps has a ton of dropouts. i would have to say that tps is shot.

Lloyd

 

I don't have experience looking at Haltech logs. I don't know the units and the scaling of the graph. Can you post the log in a .csv, .txt, or other Excel viewable format?

 

okay, I haven't seen Rotarygod around here recently (I think I read that he got married and had rightfully dedicated his time to HIS life ) so my question is open to any- and everyone.

I'm trying to see if anyone else has adapted any other TPSs to a stock throttle body (preferably something from GM) and if so, do you have photos and/or a writeup to post or PM me?