5.7 Hemi, Cable Driven Throttle, kickdown linkage for 3 speed auto

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We did. I was just trying to find a picture if someone has done it on here.
 
This one is on the 4150 type intake on an earlier hemi, but gives you the idea of how you could fab up a bracket.
hrdp_0706_08_z-hemi_swap-mechanical_kickdown_linkage.jpg
 
and one on a LS, which has the same type front TB setup
upload_2017-5-9_13-14-29.jpeg
 
I haven't used the pace 5.7, but I have a cable driven early 5.7 I used to have a 727 behind. (Now it's a 200r4). I used the lokar kickdown cable, and had a bracket made... I know I've posted a detailed description more than once. Maybe search my posts...

I attached the cable to the TB cam at an extra hole.

I then measured how much the cable moved from idle to WOT.

I then moved the kickdown lever from zero to full, and using some sort of redneck math I determined at what location on the kickdown lever I needed to drill a hole (closer to the trans than factory) so that with WOT I had full tension on the kickdown lever, and yet no pressure on it at idle.

IMG_1844.jpg
 
Here is another pic of mine how it sits now with the 200r4 TV cable geometry. It's the best pic I have of the bracket I made, the bracket is the same as when I had the 727, just the attachment point on the TB changed to meet the Criteria of GM's TV cable.

IMG_6366.JPG
 
I will also say, that much like you I was nervous about the dbw factory TB when I initially started my swap. I have been running FAST XFI for 3 yrs now, and I love the tunability of the system, but I do believe that the aftermarket stand alone ECUs will never be able to touch the extensive work that is in the factory ECUs. There are times I wish I had a factory ECU and a diablo tuner for that reason. There's way more tuners and guys upgrading hemis using that system, so they have better support in my mind. The 2003/2004 ram 5.7s ran a cable drive throttle pedal with a "bellcrank adapter" that adapted the signal to a dbw TPS signal. Modern muscle has them for sale, and I'm sure your kickdown could adapt into that box as well. I don't know if they work for the eagle 5.7, but I know they do on the early 5.7...

Joe
 
First off, Greatly appreciate you posting your bracket, that will help a bunch of PPL. Very clean setup, and very nice ride/setup.

few points on my end.

The Fast...is not my first choice...or second choice. I do agree you may have something on the table with it vs the holley, or even a professionally tuned OEM ECM.

Early and late reluctor engines are completely different animals as far as tuning goes.
We're comparing installing an engine with a mechanical TB that just needs a simple bracket made for a TV cable, Vs..

Mounting an electric gas pedal
running wires to that
mounting a double redundant bellcrank adaptor.
Running wires to that
and running a tv cable to that anyways

a box on the inner fender that has a servo in it, that mimics throttle position via a double redundant wired and mechanical linkage is not at all easier IMO.

Also don't forget that actually tuning the OEM PCM for a non-stock application costs $, and a diablo tuner only loads canned tunes, or custom tunes, it does not Tune itself, or provide a software to adjust parameters outside of very basic functions.

More than one way to tackle and project, and just food for thought.
 
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Thanks for posting those pictures, that s a real nice setup you came up with. Makes me feel more confident in the swap and that it will turn out the way I want it.
 
Thanks for the kind words about my set-up, lots of time and effort as you know.

Good info as well, you clearly know these things pretty well, and I don't know much about the early vs late stuff as far as electronics go.

I just wanna make sure the OP has thought of as many options as possible. I know in hind sight there are many things about my set up that seemed like the best plan at the time, and I'd do different with another build!

And yes, there are quite a bit more options for tuning avail than back in '10 when I bought my FAST XFI stuff.... these hemi swaps have come along way, I feel like we're finally catching up to the LS stuff...
 
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