3.4 DOHC To Fiero 3 speed Auto

Forever-Fiero · Post by **Forever-Fiero** » Thu Oct 12, 2006 9:41 pm

Im useing the 3 speed auto from my Fiero with a TDC. I know :puke: But its a (Car needs to run know, Got no money to spind on it thing). What I need to know is, What tells the the ECM the car is in gear to let it rev past 2800rpm's? If it's the gear selecter then im ok but if it's the speed sencer what do I need to make it read the speed right?

Will this trans last long with the TDC under miled abuse?

Kohburn · Post by **Kohburn** » Thu Oct 12, 2006 10:47 pm

the 3speed is a non electric tranny - for the ECM its essentially a manual tranny

Series8217 · Post by **Series8217** » Fri Oct 13, 2006 1:11 am

You don't have money, the car needs to run, and you're doing an engine swap? Worst idea I've ever heard, but good luck. Make sure its set to shift below 5,000 RPM and it miiiight not blow up the tranny. It will not last at all under abuse. Even the 4T60E was unreliable behind this engine.

Pyrthian · Post by **Pyrthian** » Fri Oct 13, 2006 9:27 am

you probably need to set the "throttle valve" cable.
in the old days, this would be called the downshift cable, or kickdown cable
its the cable that goes from the throttle, down to the trans. this lets the trans know the throttle postion, to make its decision on when to shift. when its not on, or set wrong, around 3000 is the shift point, not matter where the throttle is at. and also - this can wreck your auto tranny's internal clutch. it bases how hard to make the clutch grab by the throttle position.

Forever-Fiero · Post by **Forever-Fiero** » Fri Oct 13, 2006 5:56 pm

So will a manual Prom chip be all I need? I've never seen one in any J-yard and a custom one is to mutch right know what will an auto chip do? Is there a EZ way to trick the ECM to think the car it moving?

(You don't have money and you're doing an engine swap? Worst idea I've ever heard,)

The car hase no motor and the 3.4 runs great and I need to start driving it to work so to not kill the motor in the van with all the runing we do in it. And im not dead broke but I rilly cant spare the money for a custom chip! I know it's the right way to get it done and im all for that, Just not in this case.

Series8217 · Post by **Series8217** » Fri Oct 13, 2006 8:30 pm

A custom chip is $40. You can't afford the swap.

p8ntman442 · Post by **p8ntman442** » Sat Oct 14, 2006 1:19 pm

Forever-Fiero wrote:Ok First of all YES I can spare $40. I thought thay were more like $100 to $200. Were do you get them from at that price? This is a big help, Thinks

darth fiero

The Dark Side of Will · Sat Oct 14, 2006 8:38 pm

IE "Sinister Fiero" on this forum.

Calm down fellas.

I'm cleaning some of this crap up.

The Dark Side of Will · Sat Oct 14, 2006 8:41 pm

I'll echo the sentiments of a post I deleted: if you skimp now, it'll cost you more later.

The 4T60 that was used with the early 3.4 TDC's is a non-electronic transmission. The TH125 is a non-electronic transmission. You should be able to use the stock auto trans chip if you have a 91-93 computer.

Aaron · Post by **Aaron** » Sat Oct 14, 2006 9:29 pm

The Dark Side of Will wrote: The 4T60 that was used with the early 3.4 TDC's is a non-electronic transmission. The TH125 is a non-electronic transmission.

You sure about this Will? The 3.4 TDC used the 4T60e from 1991-1996. I thought the 'e' meant that it was electronically controlled?

Series8217 · Post by **Series8217** » Sun Oct 15, 2006 1:32 am

The Dark Side of Will wrote:I'll echo the sentiments of a post I deleted: if you skimp now, it'll cost you more later.

The 4T60 that was used with the early 3.4 TDC's is a non-electronic transmission.

No, the 3.4 TDC has always used the 4T60E.

Aaron · Post by **Aaron** » Sun Oct 15, 2006 2:51 am

No, in 97 it used the 4T65e :thumbleft:

The Dark Side of Will · Tue Oct 17, 2006 10:55 am

My bad, I thought they use hydraulic boxes in the early days.