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807 hp hemi swap in a convertible

Don selleck

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contemplating a red eye swap in a 70 challenger convertible. I know us car tool makes an advanced kit with the torque boxes frame connector radiator and inner fender supports etc. to help stiffen it up, wondering if anyone here has done a high horsepower swap in a convertible with some further input on a way to strengthen the car without turning the car into a pretzel without a cage and rollbars, looking to keep it looking as stock as possible, thanks Don.

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I can only say the convertible has a more stout underneath than a hardtop. Also there has been some big HP in these cars all along. So weld in frame connectors would be a big help along with torque boxes which might already be there. Automatic transmission would also have a lesser shock on it compared to a stick tranny. The rest of the US car tool stiffening will be a plus. I my self do not see it being a big deal on a street car. Now if it was for all out racing that would be another story.
 
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appreciate your input maybe I'm just over analyzing this, alway was under the impression that alot of structure is lost with a convertible. and yes will be a street car, but may make it to the track a few times.
 
Unless you're gonna narrow the rear end, tubs n slicks, doubtful you'll get enough traction to pretzel anything. Those Red Eye's barely get traction on the street w all the tech they have in them.
 
Don't ruin another classic. Too many people doing 3rd Gen Hemi swaps. It's almost as bad as an LS in everything.
 
I had a chain from the head to the frame in my 66ii! old school and looked like crap but it kept the motor in place! my girlfriend found out real quick sitting beside me in my 69 runner/stick/bench what happens to the shifter when a motor mount lets go!
 
Unless you're gonna narrow the rear end, tubs n slicks, doubtful you'll get enough traction to pretzel anything. Those Red Eye's barely get traction on the street w all the tech they have in them.
good point like I said I tend to over do projects
 
Don't ruin another classic. Too many people doing 3rd Gen Hemi swaps. It's almost as bad as an LS in everything.
Your really gonna whine when I tell you its a real RT car but no fender tag or build sheet wrong color from factory, but checked the numbers stamped on the cowl and its real. hmm, a turbo ls swap would be alot cheaper.
 
I had a chain from the head to the frame in my 66ii! old school and looked like crap but it kept the motor in place! my girlfriend found out real quick sitting beside me in my 69 runner/stick/bench what happens to the shifter when a motor mount lets go!
I can picture that, I had a few beaters back in the day when the air cleaner would hit the hood for the same reasons, never thought of a chain back then.
 
Your really gonna whine when I tell you its a real RT car but no fender tag or build sheet wrong color from factory, but checked the numbers stamped on the cowl and its real. hmm, a turbo ls swap would be alot cheaper.
Nope, I honestly don't care that much. I modified my original A66 340 car to build it my way but still stayed old school now with a 528" Hemi with two kits. As they say it's one car, one can build them however they want.

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for around 35k you can get the motor, 8hp trans and just about all the accessories for about 35k. you can slide the motor forward and eliminate cutting the tunnel, will have to remove torsion bar crossmenber and weld up new mounts on the k member coil overs can be added its alot less invasive if you plan it out and you can always take it back to a old drivetrain if the new owner desires. amd makes torsion bar cross member still I believe
 
Nope, I honestly don't care that much. I modified my original A66 340 car to build it my way but still stayed old school now with a 528" Hemi with two kits. As they say it's one car, one can build them however they want.

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very nice, I'm looking for something I can drive to florida if I want, not saying that beauty can't do that but would be alot easier probably cheaper and more comfortable to do so.
 
just kidding about the ls cross breeding drivetrains would never happen under my watch
 
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You are correct that high horsepower in a convertible will twist the car. You have the right idea
 
You are correct that high horsepower in a convertible will twist the car. You have the right idea
I've got 610/670 hp/tq in my '67 4dr. Would never twist anything. All my tires do is spin. Without "wide" tires, some sort of traction devices, it will never get enough traction to twist anything.
 
Somehow guys race these in stock superstock. Just saying.
 
I've got 610/670 hp/tq in my '67 4dr. Would never twist anything. All my tires do is spin. Without "wide" tires, some sort of traction devices, it will never get enough traction to twist anything.
But your 4 door has a roof.

Yes, you can race a convertible, with a full roll cage.... a 6-point bar is required at 13.49 sec.
 
for around 35k you can get the motor, 8hp trans and just about all the accessories for about 35k. you can slide the motor forward and eliminate cutting the tunnel, will have to remove torsion bar crossmenber and weld up new mounts on the k member coil overs can be added its alot less invasive if you plan it out and you can always take it back to a old drivetrain if the new owner desires. amd makes torsion bar cross member still I believe
For under $35k you can get a crazy low mileage redeye, hp90 and an RMS front setup with motor mounts already moved forward an inch. Drop out the #’s matching Motor, trans and K set up if anyone is crazy enough to go back to it and shrink wrap it.
 
Your really gonna whine when I tell you its a real RT car but no fender tag or build sheet wrong color from factory, but checked the numbers stamped on the cowl and its real. hmm, a turbo ls swap would be alot cheaper.
:BangHead:
 
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