Ok,
Time to start writing instead of just lurking.
I have had this car since 1984. Damn that makes me sound old...
I will start with cudos to all the many posters on this sight. I cannot imagine completing the amount of work many seem to blow thru. Specifically major body builds along with the go parts.

It is a California car that has been garaged most of the time. It has always been drivable. Only a single front fender has been patched and repainted on the car. This happened before I got it back in 84. The hood was painted also because it is a later addition to the car. All else is still the original paint. Many places it is so thin you can see thru it.
One small patch of rust in lower rear quarter. In front of wheel well from a plugged drain hole :-(.

Premise of this build is to add twins with dual air to air IC's.
Two things I am fairly retentive about with the car are. 1 is that if I cannot build it without bastardizing the sheetmetal then it will not happen. The second item is that with twins all is symetrical.

Car started life as a very low end base model.
318, 3spd stick and power nothing.
So changing the mechanicals doesn't mean much to me.

Car now has a 360 LA with the A833 four speed (yes Pistol grip)
Power steering added (tuff wheel too). I have gained a lot of weight over all the years of owning this and am still only up to a buck 70.
PS is way needed...
Also added Power brakes to the car way back when.

Plans for now are:
2001 5.9 motor. Already have good low milage one that will get a refurb when the time comes.
Reasoning for the later model 5.9 is that the P/S pump and alternator are mounted much closer to the motor. The WP is also somewhere around 2 inches shorter. The shorter W/pump is what ended up allowing my plan to work being retentive about the sheetmetal.
Eddy heads -Need/want-
T3 Eb@y turbos -Have-
4 speed to remain (for now).
M1 intake. I will be going fuel injection. Probably carb with the initial startup when motor is swapped in.
Megasquirt most likely.
LS coils with crank and cam triggers probable
Fuel system not decided. Possibly Bouchillon tank with internal pump.
Not interested in hearing the pump drone on.
Probably Hotchkiss frame connectors.
All the hot side piping to be SS. welded by me.
Cold side to be as mentioned above dual intercoolers with custom tanks. Aluminum piping also welded by me.
Brakes to be converted to Hydroboost
Car will also get air added.

Many of the items listed are already partially started. I tend to bounce around alot.
Start a project. let it sit... think about it for awhile... let it sit... figure it out and then jump on it until the next thought session.

Goals for the motor are to reach around 550 bhp.
This is a home built project and it will be a 100% street car.
All items are subject to change based on funds.
Main item is car will not be out of comission for any long durations. I also have a 68 Mustang (N/A) that was down for 17 years. Aint gonna happen again...

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Sounds like a cool project! Looks good with the old school yellow and rallye wheels. I get not wanting the car out of commission, it's too easy for the project to drag on forever then! The decision to go Magnum motor is a smart one, makes EFI adaption stupid easy, and the heads are supposed to flow pretty decent. Gonna keep an eye on this build for sure!

-dave

 

Looks like it will be a great project! Challengers have always been my favorite car bar none.
What 4 speed are you planning?
I HIGHLY recommend megasquirt. I am running megasquirt 2 on a 5.9 magnum. I can help you get it set up and send you a tune to get it started and running with all the correct settings.
Another ignition option besides the LS coils is a couple srt4 coil packs set up as wasted spark, I haven't done this but I know it's an option.

Good luck with the build.

 

Good luck with the build! I am building a turbo yellow Challenger, too.

 

Thanks,
Your start is what pushed me to go to the other side.
No going back now...

 

Thanks,
The current 15x7 rear wheels will end up on the front and I have another pair of 15" that I have widened to 8-1/2 inches. I split 2 hubs around the diameters and welded them back together. Long ago when I started them, wider ones were not available like they are now. I will eventually complete them just for spite. More $$$ for my time to complete them than new ones would cost. One is complete, the other needs the hub properly located and welded.
At least with the factory 74 color the yellow was toned down from the previous years. I happen to like the the yellow but am only one of a few. most conversations about it start with the "what color are you going to change the paint to?"

I am very well versed in the mechanical end of most things. But when it comes to the ele ignition, I got nothing. Definitely will be interested in the basic tune.
I am open to the srt4 coils because even though the ls coils are/were probable, it still left a bit of a bad taste in my mouth to have GM on my car.
No offence to the other crowd intended.

Years ago I was able to get a pristine all original 67 Cougar that was the epitomy of the grandma car. driven until another car was purchased and then garaged for 17 years. I still had to smog the Challenger and was having issues. So I got it as a replacement car so I could sell the Challenger. But when time came, Challenger stayed, Cougar sold. Man I am now glad I dont have the " I sould have kept that one" blues.

 

Pictures of above mentioned wheel widening.
Kind of odd seeing the tire and wheel with out a hub.
Just mounted a crap tire to leak test.

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It would be no problem to help out. I can explain to you how to use ALL the stock sensor (temps, crank, cam.... etc.) to run with MS without any additional changes to the engine or electronics, and as a said provide a startup tune with all the right settings utilizing the stock sensor.

 

A little more update info.

Starting point pic.
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Workshop shed built on side of house.
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Cramped garage. And yes they are parked only a couple of inches from each other.
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Mike.

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Little more updating.

JY motor that is supposed to only have about 90k miles. Will see when I eventually tear into it for a refurb.
This was a bonus buy... Funding for initial purchases to start this project came from a nice fat win when Green Bay won the Superbowl a couple of years ago.
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had the flanges waterjetted out of 1/2 inch SS plate.
Some torching, hammering, torching, hammering. Eventually you can get a round pipe to fit into a square (rectangle) hole.

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There was a huge learning curve on these headers. Not shown was the 3 or 4 other iterations to get them to work properly.
I first started with some #10 wall SS piping. Didnt like the overall weight the header was turning out to be. Scrapped that.
Along with the piping direction I was also machining my own flanges out of solid SS block. Cad designed my own blending surface file that matched the heads pattern and then quickly transitioned into the pipe diameter. The idea behind this is that the space between the motor and the passenger shock tower is limited because the motors are mounted offset from the car centerline.

When I scratched the pipe plans and went to mandrel bends, I also gave up on the cad file and went with the waterjetted flange.

Next learning curve.
Even though I mounted the headers and turbos on the magnum on the stand and had them positioned where I wanted. I was too confident on what I had done
and had the majority of them welded when I did the test fitting into the car.
Da... Turbos were sitting too far forward.
Time to hack the headers up again. Which resulted with mostly starting both of them from scratch.

At first look the challenger appears to have a lot of real estate. The bay is large enough but there is very little vertical room.
Eventually got it worked out.
All in all I spent more time and money then if I had paid a professional.
They have given me a lot of quality time with my tig.

Mike.

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Looking good!

 

Alright! Looking good dude. Stay on it!

 

Awesome! Keep this thread updated!

 

thanks, thanks, thanks,

With the headers progressing, time for the battery relocate.
Starting point.
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Welded up my own mount.
I knew eventually the chopped up pool fence pieces would come in handy. I tend to never throw away metal pieces.
Small holes were added to bolt it in to the frame. I was able to use an already existing hole for the wires by removing the plastic plug and adding a grommet to protect and seal it.
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End result. used the bottom tray of an aluminum enclosure with a plastic bottom tray from the JY.
Couldn't use the upper part because it will not fit. I wanted the Battery tucked in tighter.

Bay with old battery tray removed and a lot of scrubbing and it still looks like sh...
Do not like the wiring layout but it is functional for now. Plan is to add a power panel for relays and fuses in the same general area when the conversion to EFI progresses.

I found a picture of one of the cad flange pieces that I was originally designing to use.
No longer valid though.


Mike.

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With the multitude of iterations on the headers completed, another mockup to fine tune the final turbo locations.
Headers now clear the car well but I was still having an issue creating the transition connection from them to the turbo flange.
I made brackets that bolt to the lower portion of the header flanges and turbos so I could hang them where I wanted them. The future plan for support will be more robust versions of these with a connecting bar/bracket/brace between the turbos. Current setup is only adequate for mockup support. One of the things I learned was to get the turbos where you want them first instead of the other way around.
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A bit more welded and the Vband clamps added.
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Different view where you can see I had to move them forward slightly to mount my transition pipes. It started out that this was ok but turned out to be an issue when the next phase started.
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Not shown, I ended up trimming the collector shorter. I also shortened the weld seams on several of the bends to reduce their overall radii. A little nip and tuck here and there. Overall I was only looking to have them about an inch shorter.
Next phase was to relocate the radiator off of the core support and closer to the motor. This is also one of the key reasons I am going with the Magnum. WP is much shorter.
I had some mounting brackets bent up that bolt to the existing core support holes and adapt also to the radiator mounting holes.
Repositioning the radiator is really the key idea that finally pushed me into moving forward with this.
As the title suggests I will not be doing any major surgery on the car. I would then just leave it N/A.
With it's relocation, I have created openings that will allow passage of the piping to and from the intercoolers. Somewhere in all of this I will also be adding an air conditioning condensor.
I was also able to locate a JY dual electric fan setup from a late 90s chrysler. It ended up being the exact width of my radiator. The overall height is a couple of inches shorter. I will end up modifying the shroud later on to accomodate for it.

More to come...

Mike.

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Looking good!

 

Great work Mike, I love the project!

 

Looking great alot of enjoyment building everything !

 

ok this is good .. i have a 73 challenger that i will be probably running a single t70 on i will be watching this build and i hope to get this going soon .. here is some of the car ..

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Thank you, yes so far it is the build process that I am enjoying.
Eventually I will get there. Knowing next to nothing in the turbo world, especially with actual turbo sizing, I am trying to make sure what I set up can be altered easily if the needs are there.
I work at an injection mold shop and used to build the tools in house. We no longer do and I now manage the projects that are being produced in China. Ok to still be working in the field but suks to to farm them out.
Once a manufacturer always a manufacturer. This is fufilling my itch to make chips fly...