DP wiring

Knocky · 10-22-2010, 05:23 PM

Anyone know if the newer Drag Pak Challengers have a specific wiring harness, or still the SRT harness that has to be modified? I hear it is a PAIN!
Also, is there one engine management system that stands out better for these builds? (features and installation)?
Thanks all.

NewHemi · 10-22-2010, 10:30 PM

ECUs will contain all engine wiring. You can wire the rest yourself (windows, lights, fuel pump, water pump, gauges) using connectors you steal from the stock harness that comes with the car. I spent a couple of weeks trying to isolate wiring and strip out only the needed wires and connectors from the harness, and I can tell, it can't be done. The wires are so intermingled with common grounds for a boatload of things, and a ton of wires for things your car doesn't have. So just lay out wiring to where you need it, cut connectors from the old harness, and go for it.

Put water pump, lights, windows, fuel pump, gauges and what ever else you want on separate switches. You will also put the ECU power on a switch, and then it will be a matter of flipping all of the swithces and hitting your start button (which you also need to install).

As for the windows, I have thoughts on those, and you can find out my suggestions on my blog newhemiracing.blogspot.com

The ECU shouldn't control the fuel pump, and water pump, although they will give you connectors for them, and can control them. The ECU controlling the fuel pump makes getting fuel for fuel check a real challenge. The ECU will fire the pump, and wait until you are spinning and starting the engine before it hits the pump again. So even if your fuel system holds pressure pretty well, by the time you get out, get the hood off, and go to check fuel, you wont have any there to check. So wire it on its own switch. Smae for water pump, as there are times when you want the water pump running and nothing else happening.

I start to do a wiring DP wiring diagram, and when I get back from this western swing, I will finish it.

The wiring is not as hard as it seems. But you need a plan, and some patience. Good luck, and message me if you need moree info.

As for which ECU... I like the FAST system. It uses stock crank sensor, and cam sensor, and the software is nice and logical for the most part. Many people like the Big Stuff 3, but it required changes to our water pump etc, as it hangs a crank timing wheel on the front of the engine. As for the AEM, I hear that support is a problem. But FAST and Big Stuff 3 provide ample support to get you running good. And they both will help you from there. However, there are Drag Paks running very well with all three of these systems.

Price is one consideration. And another key one, is do you have somebody you already know and trust who can help you refine the tune. The mfgs will do all they can, but guys like Jeff Taylor, and Joey Wilkes can give you a competitive edge with their knowledge of these ECUs and these engines. Jeff Taylor put us in the 9's on our first run after he tuned us.

David
The New hemi Guy

Mack Reeves · 10-23-2010, 06:36 AM

I agree with David on the efi wiring. But I went a different direction... I installed a K&R system... With this system you get a switch panel that will fit right into the same location of the one that comes in the car... It attaches to another pannel that your relays and fuses are on. (App 6"x6") . This connection is a single cable and a plug that connects the two. Also in the kit you get wire that is labeled every 6", all the wire ends, connectors, and heat shrink ect. that you will need to wire. The neutral saftey switch, line lock, and what every you have can be wired thru this system.. Its neat, clean and fairyly easy to use....

You can order direct from K&R they are in Cleveland, Tennessee. Can get you a phone number but they are on the web.. Check them out before you buy... Can't hurt.... Thanks Mack

magnumv8 · 10-23-2010, 12:05 PM

personally I would let the ECU control the fuel pump relay as designed and put a momentary switch under the hood to manually enable the fuel pump relay as needed at fuel check....it is simple and easy to do, makes usage a snap......my system is set up this way......

D L Rambo

Ed Wright · 10-24-2010, 05:25 PM

Quote:

Originally Posted by magnumv8

personally I would let the ECU control the fuel pump relay as designed and put a momentary switch under the hood to manually enable the fuel pump relay as needed at fuel check....it is simple and easy to do, makes usage a snap......my system is set up this way......

D L Rambo

I use FAST, and that is the way I do it.

NewHemi · 10-24-2010, 11:18 PM

I certainly agree that doing the fuel that way would work just fine. And if we had time and been thinking more clearly, maybe we would have done that too. But we were in the pits at a race, and were thinking "quick fix"... But the main point I was making, and other also agree, is don't let the ECU handle it 100% of the time. You do need to turn it on when the ECU isnt aware of it.

And Mack Reeves makes good sense on the relay and switch thing too. If you know what yourt doing, you can get along with that, but frankly why would you want to? And besides how many racers really electric wizards..

Isn't this a nice dialogue? See what happens when Drag Pak guys can talk to each other, without being attacvked and getting flamed for having too low of a hp factor?

David
The New hemi Guy

Mack Reeves · 10-25-2010, 09:27 PM

Makes you want to set up a web site just for this .......

Mack Reeves · 10-26-2010, 07:13 AM

Quote:

Originally Posted by magnumv8

personally I would let the ECU control the fuel pump relay as designed and put a momentary switch under the hood to manually enable the fuel pump relay as needed at fuel check....it is simple and easy to do, makes usage a snap......my system is set up this way......

D L Rambo

I like the idea of a momentary switch under the hood... Thanks for the tip... Mack

magnumv8 · 10-26-2010, 04:42 PM

wire the relay like this.....

pin 30 goes to the pump

pin 87 is your power for the pump

pins 85 & 86 are the relay coil for activating the relay, wire as necessary for compatibility with your ECU.(some are positive switching and some are ground switching)....

lastly, wire your momentary switch (fused) with the connection going to pin 87A of the relay.....

this allows everything to function normally while allowing you to supply power to run the pump with the computer "off"...this also won't cause a "back-feed" condition into the computer which could damage it......

D L Rambo......

Mack Reeves · 10-26-2010, 07:42 PM

Quote:

Originally Posted by magnumv8

wire the relay like this.....

pin 30 goes to the pump

pin 87 is your power for the pump

pins 85 & 86 are the relay coil for activating the relay, wire as necessary for compatibility with your ECU.(some are positive switching and some are ground switching)....

lastly, wire your momentary switch (fused) with the connection going to pin 87A of the relay.....

this allows everything to function normally while allowing you to supply power to run the pump with the computer "off"...this also won't cause a "back-feed" condition into the computer which could damage it......

D L Rambo......

Thanks for the info..... Will set mine up this way also.... Mack

10-22-2010, 05:23 PM	#1
Knocky Junior Member Join Date: Sep 2010 Posts: 32 Likes: 0 Liked 0 Times in 0 Posts	DP wiring Anyone know if the newer Drag Pak Challengers have a specific wiring harness, or still the SRT harness that has to be modified? I hear it is a PAIN! Also, is there one engine management system that stands out better for these builds? (features and installation)? Thanks all.

10-22-2010, 10:30 PM	#2
NewHemi Senior Member Join Date: Dec 2009 Location: Ohio Posts: 472 Likes: 0 Liked 1 Time in 1 Post	Re: DP wiring ECUs will contain all engine wiring. You can wire the rest yourself (windows, lights, fuel pump, water pump, gauges) using connectors you steal from the stock harness that comes with the car. I spent a couple of weeks trying to isolate wiring and strip out only the needed wires and connectors from the harness, and I can tell, it can't be done. The wires are so intermingled with common grounds for a boatload of things, and a ton of wires for things your car doesn't have. So just lay out wiring to where you need it, cut connectors from the old harness, and go for it. Put water pump, lights, windows, fuel pump, gauges and what ever else you want on separate switches. You will also put the ECU power on a switch, and then it will be a matter of flipping all of the swithces and hitting your start button (which you also need to install). As for the windows, I have thoughts on those, and you can find out my suggestions on my blog newhemiracing.blogspot.com The ECU shouldn't control the fuel pump, and water pump, although they will give you connectors for them, and can control them. The ECU controlling the fuel pump makes getting fuel for fuel check a real challenge. The ECU will fire the pump, and wait until you are spinning and starting the engine before it hits the pump again. So even if your fuel system holds pressure pretty well, by the time you get out, get the hood off, and go to check fuel, you wont have any there to check. So wire it on its own switch. Smae for water pump, as there are times when you want the water pump running and nothing else happening. I start to do a wiring DP wiring diagram, and when I get back from this western swing, I will finish it. The wiring is not as hard as it seems. But you need a plan, and some patience. Good luck, and message me if you need moree info. As for which ECU... I like the FAST system. It uses stock crank sensor, and cam sensor, and the software is nice and logical for the most part. Many people like the Big Stuff 3, but it required changes to our water pump etc, as it hangs a crank timing wheel on the front of the engine. As for the AEM, I hear that support is a problem. But FAST and Big Stuff 3 provide ample support to get you running good. And they both will help you from there. However, there are Drag Paks running very well with all three of these systems. Price is one consideration. And another key one, is do you have somebody you already know and trust who can help you refine the tune. The mfgs will do all they can, but guys like Jeff Taylor, and Joey Wilkes can give you a competitive edge with their knowledge of these ECUs and these engines. Jeff Taylor put us in the 9's on our first run after he tuned us. David The New hemi Guy Last edited by NewHemi; 10-22-2010 at 10:40 PM.

10-23-2010, 06:36 AM	#3
Mack Reeves Senior Member Join Date: Sep 2009 Location: Elkin, NC Posts: 671 Likes: 169 Liked 44 Times in 13 Posts	Re: DP wiring I agree with David on the efi wiring. But I went a different direction... I installed a K&R system... With this system you get a switch panel that will fit right into the same location of the one that comes in the car... It attaches to another pannel that your relays and fuses are on. (App 6"x6") . This connection is a single cable and a plug that connects the two. Also in the kit you get wire that is labeled every 6", all the wire ends, connectors, and heat shrink ect. that you will need to wire. The neutral saftey switch, line lock, and what every you have can be wired thru this system.. Its neat, clean and fairyly easy to use.... You can order direct from K&R they are in Cleveland, Tennessee. Can get you a phone number but they are on the web.. Check them out before you buy... Can't hurt.... Thanks Mack __________________ Mack Reeves 2377 STOCK & SUPER STOCK

10-23-2010, 12:05 PM	#4
magnumv8 Member Join Date: Feb 2009 Location: Coraopolis, Pa. Posts: 172 Likes: 0 Liked 0 Times in 0 Posts	Re: DP wiring personally I would let the ECU control the fuel pump relay as designed and put a momentary switch under the hood to manually enable the fuel pump relay as needed at fuel check....it is simple and easy to do, makes usage a snap......my system is set up this way...... D L Rambo

10-24-2010, 11:18 PM	#6
NewHemi Senior Member Join Date: Dec 2009 Location: Ohio Posts: 472 Likes: 0 Liked 1 Time in 1 Post	Re: DP wiring I certainly agree that doing the fuel that way would work just fine. And if we had time and been thinking more clearly, maybe we would have done that too. But we were in the pits at a race, and were thinking "quick fix"... But the main point I was making, and other also agree, is don't let the ECU handle it 100% of the time. You do need to turn it on when the ECU isnt aware of it. And Mack Reeves makes good sense on the relay and switch thing too. If you know what yourt doing, you can get along with that, but frankly why would you want to? And besides how many racers really electric wizards.. Isn't this a nice dialogue? See what happens when Drag Pak guys can talk to each other, without being attacvked and getting flamed for having too low of a hp factor? David The New hemi Guy Last edited by NewHemi; 10-24-2010 at 11:22 PM.

10-25-2010, 09:27 PM	#7
Mack Reeves Senior Member Join Date: Sep 2009 Location: Elkin, NC Posts: 671 Likes: 169 Liked 44 Times in 13 Posts	Re: DP wiring Makes you want to set up a web site just for this ....... __________________ Mack Reeves 2377 STOCK & SUPER STOCK

10-26-2010, 04:42 PM	#9
magnumv8 Member Join Date: Feb 2009 Location: Coraopolis, Pa. Posts: 172 Likes: 0 Liked 0 Times in 0 Posts	Re: DP wiring wire the relay like this..... pin 30 goes to the pump pin 87 is your power for the pump pins 85 & 86 are the relay coil for activating the relay, wire as necessary for compatibility with your ECU.(some are positive switching and some are ground switching).... lastly, wire your momentary switch (fused) with the connection going to pin 87A of the relay..... this allows everything to function normally while allowing you to supply power to run the pump with the computer "off"...this also won't cause a "back-feed" condition into the computer which could damage it...... D L Rambo......