3.4DOHC 4spd Manual or Auto?

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Identity Crisis
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3.4DOHC 4spd Manual or Auto?

Post by Identity Crisis »

The 86 GT I am going to drop the 3.4DOHC into currently has a 4spd manual. THe engine is coming with a 4T60e Auto.

I dont mind either Transmission. But I dont have any experience with a 4spd for performance I have only ever dealt with the 5 spd Muncie or Isuzu.

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draven
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Re: 3.4DOHC 4spd Manual or Auto?

Post by draven »

The auto with the stock computer code is rev limited to 6500 with a 6250 shift point while the stock manual is set to 7250 I believe. If the ECU is the 97 you can use HPTuners to play with the rev limiter quite easily
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Re: 3.4DOHC 4spd Manual or Auto?

Post by Identity Crisis »

I was going to use the 7730 cause I may go with boost later.
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Re: 3.4DOHC 4spd Manual or Auto?

Post by The Dark Side of Will »

Which code mask? The RPM parameter in the data stream is only 8 bits, so the highest RPM that ECU can report is 6375 with the 25x multiplier. Ryan Hess coded some sections to use a 35x or so multiplier in the $A1 code mask he modified for use with the Northstar.
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Re: 3.4DOHC 4spd Manual or Auto?

Post by Identity Crisis »

Will ya got me on that programming. I have yet to teach myself coding so I don't get what you are mentioning completely. But I have been seeing a lot on the forums and kind of get what you are saying but not the nitty gritty.
It may just be simply easier to just keep it with the Auto, and the stock ECM.
Thanks for the responses BTW guys.
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Re: 3.4DOHC 4spd Manual or Auto?

Post by draven »

You could always go with the manual ecu from the 1st Gen LQ1's and go with the 4spd and then swap it out for the 7730 later on... maybe step up to a getrag 5sp 282 or even an F23...
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Re: 3.4DOHC 4spd Manual or Auto?

Post by ericjon262 »

draven wrote:You could always go with the manual ecu from the 1st Gen LQ1's and go with the 4spd and then swap it out for the 7730 later on... maybe step up to a getrag 5sp 282 or even an F23...

the 9396 is very similar to the 7730. IIRC, 770 code can be run on a 9396. the 9396 has more RAM though, so it doesn't necessarily work the other way around.
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Re: 3.4DOHC 4spd Manual or Auto?

Post by Identity Crisis »

Come to find out the Transmission has been fully performance built (4T60e) and has a 2800 Stall.
So which Fiero side Axles do I use? Auto or manual?
Use the 4T60e cups tranny side and then install the shafts from the fiero inwards or, use the shafts from the 4T60e out to the Fiero outer joint at the wheels?

Anyone here have done the 3.4DOHC auto swap?

FYI the reason I am staying auto is cause of my injury to my left leg while on Military Service, I just can no longer shift like I used to.
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Re: 3.4DOHC 4spd Manual or Auto?

Post by The Dark Side of Will »

The Fiero right side manual axle is a couple of feet too long to use with an automatic. I'm not sure if the Fiero left manual axle just needs the inner cup swapped or what...
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Re: 3.4DOHC 4spd Manual or Auto?

Post by ericjon262 »

The Dark Side of Will wrote:Which code mask? The RPM parameter in the data stream is only 8 bits, so the highest RPM that ECU can report is 6375 with the 25x multiplier. Ryan Hess coded some sections to use a 35x or so multiplier in the $A1 code mask he modified for use with the Northstar.
nAst1 is capable of going way higher than that, it's modded $A1 mask

http://60degreev6.com/forum/showthread. ... pts-Thread
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Re: 3.4DOHC 4spd Manual or Auto?

Post by The Dark Side of Will »

LOL at the 66 page thread... some weekend when I have time.
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Re: 3.4DOHC 4spd Manual or Auto?

Post by Identity Crisis »

So use the Auto axles from a THM125 then with my 4T60e?
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Re: 3.4DOHC 4spd Manual or Auto?

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Re: 3.4DOHC 4spd Manual or Auto?

Post by ericjon262 »

The Dark Side of Will wrote:LOL at the 66 page thread... some weekend when I have time.
fair enough... long story short, on a test bench they've logged 12,750 rpm
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