[kplake]

I have org. factory eng harness & computer. I have adapded 700R4 trans,what kind of problems am I getting into not having harness plugged into a trans if any ? will eng.perform proper. I do have the org. 5 speed automatic trans but its big, heavy,and being computer control very pricey to repair !

[LATECH]

Originally Posted by kplake

I have org. factory eng harness & computer. I have adapded 700R4 trans,what kind of problems am I getting into not having harness plugged into a trans if any ? will eng.perform proper. I do have the org. 5 speed automatic trans but its big, heavy,and being computer control very pricey to repair !

Chances are it will run in a limp mode, not making full power as it sees a trans problem (due to there isnt one that it recognises.)
What would work is a pcm from a standard set up with your 700r 4 , eliminating the need for any feedback from the trans (other than VSS) to allow the PCM to strategise operations.
You may want to look into an aftermarket EFI controller that is tunable to allow fine tuning the power and driveability of the system.

[EagleMark]

Wonder if you could find PCM for manual trans? Chnaces are it would still need some programming to remove emmissions or body control modules etc... I really know of no one who does these but I'm sure there are?

I've seen MegaSquirt boards mounted inside many PCMs to look stock. Pretty verstile to tune, lots of options and may find one for TCC lock up below...

Then still have no lock up for TCC but that could be hard wired into switch for highway cruise.

[kplake]

I have located standered trans computer which i've been told should correct my vech from going into limp mode . as far as emission for performance i have all sensor related to eng. and orig fact harness which i will cut down to fit my needs . i also have both ox sensor before converters. since im not running converters will this be a problem ? God knows what else i might encounter. looking for any advice to help me through this convershion. i'm starting to 2nd guess my self ken

[EagleMark]

O2 sensors before converter without converter will not be an issue. If the system has O2 sensors after conveter they can be modified to work fine.

Your going to need a VSS... proper fuel pressure and I don't know if that has a return line or returnless? EGR is a good thing. Charcoal canister purge can be dealt with. Need to get error codes for that engine and it will give you an idea of what is going to set if you don't have it. Like did it have a Power Steering pressure signal?

It's a worthy project and obtainable. You'll love the end result!

[Centerline]

I'm just curious here..... why not use Mopar's 545RFE five-speed automatic overdrive transmission? It bolts up to the hemi and is controlled by the hemis computer. On the surface this looks to be the way to go. Just wondering why you chose the GM trans.

Centerline
HotRodsAndHemis.com

"Instructions are just the manufacturers opinion of how it should be put together". - Tim Allen

[ethn_bert]

Originally Posted by Centerline

I'm just curious here..... why not use Mopar's 545RFE five-speed automatic overdrive transmission? It bolts up to the hemi and is controlled by the hemis computer. On the surface this looks to be the way to go. Just wondering why you chose the GM trans.

Centerline
HotRodsAndHemis.com

"Instructions are just the manufacturers opinion of how it should be put together". - Tim Allen

X2

The 5 speed shouldn't cost too much to repair. Plus that five speed is going to give you better performance compared to the 700r4

[emwolb]

i've also got an 04 5.7 hemi and the 5 speed auto trans. i am using the auto trans that came with the motor only because i want to keep it simple. i got an 04 ram 1500 chassis/engine trans, less body and interior. street and performance in mena arkansas has been very helpful. i got their harness that lets me use the factory ecm and all sensors, etc. you know that in 04, there was one brain. unlike the 03 which had one for the motor and another for the trans. the next thing to attack is the throttle by wire. lokar advertises that they make a hall effect pedal that will work with gm, ford, and mopar. it'll power my little chopped and channeled 24 dodge coupe just fine. good luck with your project. as far as opinions, i think centerline has the right idea.

[emwolb]

the 5.7 fuel system is a straight pressure to your fuel rails. in order to use an aftermarket fuel pump, you can use a c-5 series fuel filter. it has one inlet from the fuel tank where you have your pump, and one outlet that goes forward to feed your fuel rails. it also has a return line that brings the excess fuel, the gas your motor won't use, back to the fuel tank. now the interesting part of why this works is that the corvette fuel filter not only filters the fuel, it also regulates the fuel pressure to the rails. fram makes them and they're the simplest way to regulate your fuel pressure. they're not expensive at all, so it's a win/win. look at "street & performance" website, and you can learn more. the filter cost me i think around 12 bucks. far cheaper than going with a specially adjustable pressure regulator, it does the job, and it's much simpler. i hope this helps.