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Pedal Madness...adding a clutch pedal and a DBW Holley Throttle Pedal

Aron

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Hey All,
Progress in fits and starts with my '68 Charger. What started as a non-numbers matching 440 rebuild 11 years ago has turned into a full tear down and resto-mod rebuild. I've got a stroked 3rd gen Hemi 6.1. I have the Terminator X Max ECU / harness, etc. I have purchased the recomended pedal from Holley as this is Drive By Wire. In parallel, I have a Tremec TKO 5 speed (this Charger was originally an automatic), which means I'm going to be hanging a new clutch pedal as well.

Wondering if anyone can start me off on the right foot / from scratch to avoid mistakes (also known as "doing it over / taking 5 times as long") to get all of these pedals in the right way. I'm a visual learner, so YouTube links would be amazing if you have them (or have made them).

One other key question - anyone have a slick solution to running their ECU harness through the firewall and mounting the equipment in a safe place? I'm going for a (relatively) smoothed firewall appearance.

As always, thank you to any and all for the help, I'm learning most all of this for the first time - and I have to take vacation days to work on it, full time job + two kids + soccer coaching is...well, it's not a Mopar-first kind of recipe.

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Hydraulic. Beautiful 69 by the way.
 
Hydraulic. Beautiful 69 by the way.
Thanks. Nothing special on the install of the pedals. I just followed the instructions and it pretty much fell in place. Having the main brake pedal part in is 3/4 of the battle. Wish I had taken more pictures. I have manual brakes so finding a mounting place for the hydraulic reservoir was pretty easy.
 
For most of the EFI builds I have done, I route the harness for the ECU through the tunnel hump up near the firewall ensuring to give enough room for the HVAC system. What this allows me to do is to mount the ECU inside the car (usually above or underneath the glove box). Also, thus brings all of the cables out just behind the engine which yields a clean look. This is a 71 Charger but I have done the same thing on a 69 Ply Wagon and a 73 Cuda.

On my 70 Challenger I mounted the HP ECU inside of the drivers fender above the factory fender brace which worked out ok.

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Nice! Thank you both - I think I've figured most of the pedal stuff out - just had to do some digging and deep examination of the original pedal bracket.
70 Chall - one quick question - the trans tunnel entry makes great sense. Did you drop down the harness behind the engine? Any wrap / protection you use on that and/or way you secured it to the firewall on the way down?

Thanks again!
 
Nice! Thank you both - I think I've figured most of the pedal stuff out - just had to do some digging and deep examination of the original pedal bracket.
70 Chall - one quick question - the trans tunnel entry makes great sense. Did you drop down the harness behind the engine? Any wrap / protection you use on that and/or way you secured it to the firewall on the way down?

Thanks again!
@Aron
Not sure I exactly understand what you are asking me but here is the answer to what I think the question is; the harness comes from inside the car and will essentially be on top of the trans at that point, it takes a little fiddling around to get it in there through the hole, having 2 people is very useful. I use a 2 piece grommet on the hole itself which I think is about 2.5" (check the Holley instructions), the grommet is

Seals It Split Grommet 3" OD, 1" Hole, Flat - SGS35100​


It is available from Amazon for $34 and can be molded to fit the contour of the floor with a rubber mallet and then screwed to the floor using sheet metal screws, self tappers or nutserts (my favorite).

As to protecting the harness, it come with a split loom wrap which is fine IMO.

BTW and FYI, if you answer someone and start with the @ symbol and then their screen name they should get an automatic notice that you are talking to them, that way you get an answer in a timely manner.
 
@Aron
Not sure I exactly understand what you are asking me but here is the answer to what I think the question is; the harness comes from inside the car and will essentially be on top of the trans at that point, it takes a little fiddling around to get it in there through the hole, having 2 people is very useful. I use a 2 piece grommet on the hole itself which I think is about 2.5" (check the Holley instructions), the grommet is

Seals It Split Grommet 3" OD, 1" Hole, Flat - SGS35100​


It is available from Amazon for $34 and can be molded to fit the contour of the floor with a rubber mallet and then screwed to the floor using sheet metal screws, self tappers or nutserts (my favorite).

As to protecting the harness, it come with a split loom wrap which is fine IMO.

BTW and FYI, if you answer someone and start with the @ symbol and then their screen name they should get an automatic notice that you are talking to them, that way you get an answer in a timely manner.
@70chall440
Thank you very much - really helpful advice and great pictures.
I bought a grommet (the one Holley recommends) but it's only 2" - I like your idea of getting something a little bigger - seems like a lot of wires need to pass through. I may have to put my pass through a little higher up on my firewall - not a ton of room between the bellhousing and the trans tunnel - I'm guessing that won't make a huge difference.

Right now, my goal is to figure out where all of the holes need to go in this car to get the newer equipment in place so I can then take it all apart and send it to paint and body. This process has been extended (full time job, two young kids), but I'm getting there. You've given me a lot of good advice over the years (!!..more than I'd like to admit). Thanks for all of the help. If you have any other tips / tricks for this wiring mock up process I'm all ears.

Thanks again,
-Aron

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@Aron

I am happy to help where I can and even happier that some of my advice has been helpful. As to other advice I will give you the follow, if you already know it or are on top of it so be it but this is what comes to mind;

Mock up everything you can and mock everything up with everything else in place when possible. This will save you a lot of pain later on.

As to the wiring itself, you need to have a good grasp on everything you intend to use/have that required electricity. This all needs to be positioned/laid out so you know where wires have to go.

Make a LOT of grounds, everything needs to be grounded to the chassis and you need to ensure that you have a very good ground from the battery to the chassis. The only exception is your ECU which MUST be grounded directly to the battery (also the positive needs to go directly there).

Build an electrical book (3 ring binder), print off the stock wiring diagrams (instrument and engine) even though you are running a G3 Hemi, the car will still run things like the head and taillights, dome light, perhaps the wiper motor, etc. You should also have copies of the Holley electrical information in there. I personally draw wiring diagrams in Power Point and put them into the binder, specifically for things like the wiper and headlight switch but also for things like my modified headlight circuit (using relays), electrical fan wiring, and even my stereo wiring. This has several benefits, first is that it makes you think about the wiring, second is that is something doesn't work you have a place to refer to and lastly should you ever sell the car (or even several years down the road) there is a reference to go to should there be problems.

I crimp and solder every connection, I know some argue that it is not needed and some even argue against it but by doing so you know there is a connection and you will not have an issue with a loose one. Yes the solder can be brittle and can break in some cases but I only use a very small amount per connection and it has never been an issue. I good solder system is essential, I like and use the Weller solder station but there are many out there.

Invest in good/decent crimpers, that said you will need a variety to really get the job done across the board. I have a lot of them as every time I would see something new I bought them but this isn't really necessary and it does not have to cost huge money, but it should not be cheap either. In general I use tools similar to these 2 the most;
Amazon product ASIN B0006M6Y5M
Amazon product ASIN B096M8K3WG
Harbor Freight can be a great source for things like this plus they have a decent hydraulic crimping tool that is very handy.

Use relays for any high draw application such as headlights, driving lights, fans, fuel pump, amps, etc.

DO NOT USE insulated connections like you buy at the parts store or Walmart! You can use those but strip off the insulation then crimp, solder and heat shrink them.

Electrical type should not be used as insulation except in temporary or emergency situations. It can be used to bind wire covering and the like though, however get quality tape such as 3M Super 33.

Split loom wire covering is cheap on Amazon and looks nice plus it protects your wiring.

I can on and on but you've probably had enough by this point. Feel free to ask questions as there are much smarter people on here than me especially when it comes to electrical issues. That said I will leave you will one last thing on wiring; when the car is done and you are showing it you will be judged on the wiring. If it is all shiny and nice but has rats nest wiring everyone will notice, however if the wiring is neat and organized, hidden when applicable, etc. it will only compliment the build. You don't have to be an artist but don't be lazy about it either. Oh, one last last thing TEST TEST TEST everything you can meaning every component and circuit, it will save you a lot of headache later.
 
@Aron

I am happy to help where I can and even happier that some of my advice has been helpful. As to other advice I will give you the follow, if you already know it or are on top of it so be it but this is what comes to mind;

Mock up everything you can and mock everything up with everything else in place when possible. This will save you a lot of pain later on.

As to the wiring itself, you need to have a good grasp on everything you intend to use/have that required electricity. This all needs to be positioned/laid out so you know where wires have to go.

Make a LOT of grounds, everything needs to be grounded to the chassis and you need to ensure that you have a very good ground from the battery to the chassis. The only exception is your ECU which MUST be grounded directly to the battery (also the positive needs to go directly there).

Build an electrical book (3 ring binder), print off the stock wiring diagrams (instrument and engine) even though you are running a G3 Hemi, the car will still run things like the head and taillights, dome light, perhaps the wiper motor, etc. You should also have copies of the Holley electrical information in there. I personally draw wiring diagrams in Power Point and put them into the binder, specifically for things like the wiper and headlight switch but also for things like my modified headlight circuit (using relays), electrical fan wiring, and even my stereo wiring. This has several benefits, first is that it makes you think about the wiring, second is that is something doesn't work you have a place to refer to and lastly should you ever sell the car (or even several years down the road) there is a reference to go to should there be problems.

I crimp and solder every connection, I know some argue that it is not needed and some even argue against it but by doing so you know there is a connection and you will not have an issue with a loose one. Yes the solder can be brittle and can break in some cases but I only use a very small amount per connection and it has never been an issue. I good solder system is essential, I like and use the Weller solder station but there are many out there.

Invest in good/decent crimpers, that said you will need a variety to really get the job done across the board. I have a lot of them as every time I would see something new I bought them but this isn't really necessary and it does not have to cost huge money, but it should not be cheap either. In general I use tools similar to these 2 the most;
Amazon product ASIN B0006M6Y5M
Amazon product ASIN B096M8K3WG
Harbor Freight can be a great source for things like this plus they have a decent hydraulic crimping tool that is very handy.

Use relays for any high draw application such as headlights, driving lights, fans, fuel pump, amps, etc.

DO NOT USE insulated connections like you buy at the parts store or Walmart! You can use those but strip off the insulation then crimp, solder and heat shrink them.

Electrical type should not be used as insulation except in temporary or emergency situations. It can be used to bind wire covering and the like though, however get quality tape such as 3M Super 33.

Split loom wire covering is cheap on Amazon and looks nice plus it protects your wiring.

I can on and on but you've probably had enough by this point. Feel free to ask questions as there are much smarter people on here than me especially when it comes to electrical issues. That said I will leave you will one last thing on wiring; when the car is done and you are showing it you will be judged on the wiring. If it is all shiny and nice but has rats nest wiring everyone will notice, however if the wiring is neat and organized, hidden when applicable, etc. it will only compliment the build. You don't have to be an artist but don't be lazy about it either. Oh, one last last thing TEST TEST TEST everything you can meaning every component and circuit, it will save you a lot of headache later.
@70chall440:
This is AMAZINGLY helpful! As always. I appreciate the advice. A wiring binder is a great idea. I have kept electronic folders throughout this process (fairly reliably) and it has been critical. As various life things interfere with this build, I need documents to come back to in order to figure out where I left off and where I can pick up again. As time has gone on, things have evolved with the build and keeping notes with updates has been helpful. I should have done that WAY more at the tear down stage, but live and learn.

I took the plunge and bought and Infinity Box electrical system - after I get the ECU system mocked in, I'm going to open that box and tackle that. I'll get the binder started now.

Thanks again, and I'll hit you with more questions as I keep going - great advice on developing plenty of grounds to chassis along the way. I took an online wiring-automobiles-for-beginners type course and that was helpful - especially on how to test, basics about circuits, amperage vs. voltage, etc.

-Aron
 
@Aron

No problem, I am happy to help. As to the binder, actually I make a variety of binders for my builds such as;

Drive Train (this would cover engine, trans and rearend)
Brakes/Suspension
Paint and body
Electrical
General information (this is where I would put things that don't fit in any of the others)
Receipts
HVAC

I buy binders from Walmart or even Amazon, some of the binders will be 1" whereas things like receipts is 3" but most are 2"

I also have a "build book" which is an excel spread sheet where I capture how I see the build in the beginning and all of the items I buy for the build as I go along which includes when I bought them and from where (sometimes the PN as well). This has come in very handy a few times. Unlike many people I do like to keep track of what I spend on my builds only so I know as it has no bearing on worth or resale value if that ever became an issue.
 
I second the wiring coming in near the tunnel. Mine is a little more on the firewall, but in the same area. It let me run the wires up underneath the heater box. I ended up mounting my terminator in the glovebox so all the wiring went in front of the dash. Wires are still dangling in the picture, but you get the idea.

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Cool build, just noticed this thread
:thumbsup:
 
Nice work, I ran my Holley term x setup in the glove box as well. As for the pedal, I used the factory wedge my DBW pedal came with and mounted pretty high on the firewall.
 
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