Variable TPS Upgrade...

[winstontj]

Is there a Variable TPS upgrade for the e30 m20?

Just wondering. I know nothing about the stock BMW engine management system and may eventually switch over to MegaSquirt. In the meantime has anyone found a clever way to upgrade to a variable TPS (and a way to actually have it do something for the engine management system?

TIA,
TJW

BTW,
A 525i auto has the same exact size TPS (6-prong plug) as ours only it's variable 0-5v rather than ours which is 3position.

[MrK]

AFAIK, the 525i TPS is a direct bolt-on, and a good idea if you'll be running MS. However the stock TPS is necessary if you'll be keeping the stock ECU.


Did I state the obvious? Perhaps. Sorry if I did LOL.

[winstontj]

I just don't know a thing about the stock ecu. I don't even know what a "custom burn" chip is. Is this a Motronic injection system?

[jlevie]

The ECU used in an E30 would not know what to do with a variable throttle position sensor. It only can use a signal telling when the throttle is at idle or at wide open throttle. The only reason to fit a variable throttle position sensor would be if you are replacing the ECU with one that is more sophisticated (MegaSquirt or as part of a late model engine swap).

[MrK]

I just don't know a thing about the stock ecu. I don't even know what a "custom burn" chip is. Is this a Motronic injection system?

Yes this is a Motronic 1.1/1.3 injection system, and a "custom burn" chip is a chip that is made with certain spark timing and fueling maps according to a tuning session, and then it is placed inside the stock ecu, replacing the existing chip. Chips are easy to change on Motronic 1.1/1.3 ecu's, just a matter of opening up the box, yanking the chip out (carefully), and slotting the other chip in. Plug n play.

Hope that clears things up a bit.

[rs4pro3]

However the stock TPS is necessary if you'll be keeping the stock ECU.

not true the 525i TPS is both a variable and regular switch TPS(hence the 6 wires)
3 are for the variable part and 3 are the normal open close wires. I have the 525i one on my car, stock ecu using the normal wires, and my piggyback ussing the variable section.

[winstontj]

not true the 525i TPS is both a variable and regular switch TPS(hence the 6 wires)
3 are for the variable part and 3 are the normal open close wires. I have the 525i one on my car, stock ecu using the normal wires, and my piggyback ussing the variable section.

Ooohhhh.... Please do tell more about this piggyback....

I'm probably going to go the route of MS (since I have all the parts built for the 2002 i'm cutting up tomorrow) eventually and I'd like to slowly ease into things. I'll start with the crank trigger & hall sensor and data log RPM's for a few months then move to spark, etc. but to have the variable TPS there to do some additional data logging would be excellent.

[87-325ic]

is this 525i an e28 or e34?

caare to shed more light on the subject of your install with the piggyback?

[rs4pro3]

you use the early 525i m20 automatic TPS like from 89 models. My piggyback is an Apexi SAFC and is being used to convert my e36 maf signal so the 325i ecu will read it. It uses rpm's and throttle position as it's map coordinates.

[87-325ic]

is all i need the tps,

im pretty sure the m20s in those early 5ers were the 2.7 ltr eta versions..

the throttle body is smaller, is it still fine?

when looking at it on the car.. how do i know its the right one?

[rs4pro3]

the early e34 525i's used a m20 I motor, the variable TPS is only on the automatic cars, the variable section was used for the auto tranny computer to help determine gear kick downs etc...
The correct TPS has a round 6-pin plug on it, where as the normal m20 tps is a flat 3-pin plug

[Turf1600]

Is this the right TPS?

http://www.realoem.com/bmw/showparts.do?model=HC23&mospid=47402&btnr=13_0291&hg=13&fg=15

#2 in the pic

[87-325ic]

the part number may be right, but the picture looks wrong from his description..

So these are on the early e34!!!??

crap, cause ive got a nice e28 sitting in a yard here, and its auto
will this one work?

[rs4pro3]

ya only on the E34, some rare late model e30's may have them. The part number is 13631707320
The e28 late auto's have them but the throttle body spins the opposite direction so they won't work.

[Turf1600]

Here's one for sale - Bid away!