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Lonestag
06-07-2009, 11:46 PM
Well,
I just got into the mustand TB project that I bought from partyball (which had been begun by another user). It looks pretty streight forward.

What had been done thus far was to make an adapter to fit the mustang TB onto the celica pleneum. It looks like there had also been some porting to match the 60mm TB to the 50mm outlet for the celica TB.

I was worried that the TPD situation would be over my head, because changing from one resitance range to another with wiring is way out of my skill set, but I think I found a way around that.

It looks like the TPS on the celica can be easily modified to connect with the mustang TB. The celica TPS has a lot of extra metal around the center that can be cut to fit the screws, and if I fill in the center with some sort of filler and then cut a recess for the mustang tb's TPS shaft, I think it will work.


I know this is a lot of half-coherent conjecture and pics would be nice, so if I get this project all together, maybe one of the mods will let me delete this post and put in a write up instead.

Also, I'm kinda lost on what I need to do vacume hose wise, so if anyone knows the ins and outs of vac connections on a mustang TB, that would be swell.

beingblueeyes
06-08-2009, 02:59 AM
Why not just use the mustang tps? (I’m assuming that the mustang/ford also use a 5 volt tps sensor) the 4 wires on a 5s tps are
1)5 volts in
2) ground
3) tps sig.
4) idle switch that closed (i think to ground) when the throttle is shut all the way

here is how to figure out what lead/pin dose what on the mustang/ford tps

" Throttle Position Sensor Wiring

To hook up your throttle position sensor (TPS), disconnect the TPS, and use a digital multi-meter. Switch it to measure resistance. The resistance between two of the connections will stay the same when the throttle is moved. Find those two - one will be the +5 Vref and the other a ground. The third is the sense wire to MegaSquirt. To figure out which wire is the +5 Vref and which is the ground, connect your meter to one of those two connections and the other to the TPS sense connection.

If you read a high resistance which gets lower as you open the throttle, then disconnected wire is the one which goes to ground, the other one which had the continuous resistance goes to the +5 Vref from the MegaSquirt, and the remaining wire is the TPS sense wire. " - MicroSquirt wiring guide

so after that all you need to do is after that is wire/setup a "WOT" switch so that when the throttle is closed it completes the cercet in the switch (to again I think is a ground)

Lonestag
06-08-2009, 03:44 AM
Actually, oddly enough, I think my celi's TPS only had three wires out...

Yeah, just checked, celie's TPS only has 3 wires.
-Maybe b/c it's a rev 1 5S?

The only reason I wouldn't use the ford TPS is that I don't know if the resistance values are the same, I know they are both a five volt system, but I don't know if they very within that voltage in the same way.

If I use the celi TPS, it will be a plug and play solution, which would be nice.

CriScO
06-08-2009, 06:18 AM
You don't have to worry about resistance with the three wire. The only values are open and closed. I'm gonna explain it using the original design because it's a little easier to understand.

Simply put, the bottom pin is the idle signal(IDL). It's closed when the throttle is closed. With the circuit closed, voltage is sent to the ECU to tell it that the throttle is shut.

When set to stock value, the bottom pin's circuit opens shortly after the butterfly valve is moved, when the distance from the throttle stop is at about .070mm. This is about 1.5 degrees rotation. This circuit remains open as long as the throttle is past that value. With no voltage from the bottom pin, the ECU knows the throttle is open.

The top pin sends no voltage until the throttle is rotated about 70 degrees. This pin is the power switch(PSW). When voltage is present at the top pin, the ECU considers it to be at WOT.

So internally the switch works like this:
Closed Throttle - Bottom and center pins connected. (voltage in IDL circuit)
Open Throttle - No pins connected.
Wide Open Throttle - Top and center pins connected. (voltage in PSW circuit)

Of course our sensors are the later design which sends the voltage to ground instead of straight to the ECU, but the idea is the same, just reversed(i.e. the IDL signal is off when the throttle is closed instead of on). That should give you a basic idea of how it works, though.

85gtsblackman
06-08-2009, 06:34 AM
out of curiousity why did the po use a ford 60mm tb. the supra tb and some other 4 and 6 cyl toyotas are 60mm. also some have interchangeable tps sensors.

T-spoon
06-08-2009, 06:59 AM
out of curiousity why did the po use a ford 60mm tb. the supra tb and some other 4 and 6 cyl toyotas are 60mm. also some have interchangeable tps sensors.

My guess is cost? Mustang parts are plentiful and cheap?

85gtsblackman
06-08-2009, 07:50 AM
but throttle bodys dont usally wear out, plus if it comes from a junkyard then its probally the same price as any other.


dont really make sense to use ford

Lonestag
06-08-2009, 03:20 PM
I don't know why they chose the ford other then it cost like $15 bucks for a nearly brand new TB...

So you are saying that if I directly wire it up it should work? That would be cool.

beingblueeyes
06-08-2009, 07:52 PM
but throttle bodys dont usally wear out, plus if it comes from a junkyard then its probally the same price as any other.


dont really make sense to use ford


The only thing I can think of is bolt pattern on tb (if memory serves) the ford 5.0 tb bolt pattern is just about a perfect square. I’m not sure however on the Toyota tbs bolt pattern you suggested. Or whoever started this project just had a ford tb on a shelf….

lone try just wiring it up, its only 3 wires.....

CriScO
06-08-2009, 07:57 PM
So you are saying that if I directly wire it up it should work? That would be cool.
That's what I'm thinking. I'm gonna do some more research today if I get a chance.

Lonestag
06-08-2009, 09:08 PM
Well, if I wire it up and it runs really rough, i'll give the other method a try.
But if it just wires right up, hell, that will be nice.

It really looks like it would be a fairly simple drill, cut and glue job to get the Celi TPs on the stang TB.

beingblueeyes
06-09-2009, 02:19 AM
That's what I'm thinking. I'm gonna do some more research today if I get a chance.

Not to sound like an ass but what are you researching? Its lonestag’s turn to swap intake manifolds /cut and male/female 3 wires something that takes like maybe 40 min (if he needs to switch back to the stock intake manifold)

As for the vac lines you only need 3
Map sensor
Fuel psi reg.
Brake vac booster

CriScO
06-09-2009, 06:26 AM
Not to sound like an ass but what are you researching? Its lonestag’s turn to swap intake manifolds /cut and male/female 3 wires something that takes like maybe 40 min (if he needs to switch back to the stock intake manifold)
That's fine, but I prefer not to do any wiring until I know what the effect will be. Say it doesn't work and he does end up retrofitting the Toyota TPS. Personally I'd be pissed if I had to set it back to stock/write off the wiring I did on the TPS end after doing that, even if the wiring is simple. Jumping straight in isn't everyone's preference. I'm not a fan of guessing when it comes to wiring.

At any rate, I'm interested to see how those sensors work internally. There's a lot of aftermarket TB's that use TPS sensors based on the 302's. It wouldn't be bad knowledge to have. I'm not asking Lonestag to wait for me by any means, I'm researching it either way. Because even if hooking it straight up doesn't work, there may be another way that will.

BTW, I had a 5.0 TPS on the shelf, but they don't come apart as easily as ours. :hehe: I wasn't about to pay for it to break it open, so I'll have to look up the Ford equivalent of the BGB...

Lonestag
06-09-2009, 10:54 PM
Hey guys, while I've been messing with this project, I noticed that the intake runners were fairly rough on the inside. Is this a part that would benifit from a little polishing, or does the roughness create turbulance that helps the mix?

Just looking for thoughts.

partyball
06-10-2009, 05:48 AM
Glad to see your tearing into the project so quickly. Hope you get the TPS figured out. And as for the people wondering about the mustang throttle body. The original owner of the project (Hooligan) got the brand new throttle body for $20

jaydog82
06-11-2009, 07:12 AM
i just finished porting out my stock throttle body and intake manifold to about 58mm, i also made a new 58mm throttle plate. good luck with the ford tb

85gtsblackman
06-11-2009, 08:08 AM
results?

jaydog82
06-11-2009, 05:32 PM
i dont know yet, i am in the middle of replacing my block. i will post results when i get it running.

jaydog82
06-11-2009, 07:37 PM
here it is
http://www.celicatech.com/forums/showthread.php?t=42032