Modern Drivetrain Swap

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71chally

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Looking at swapping in a modern hemi, trans, suspension and interior into my 71 Challenger.

I don't have a motor, trans, engine bay harness, radiator, driveline, rear gear set, or much of the interior stuff sans the dash and panels. So you can see why this particular swap would work good for me.

Trying to decide between using the unibody sub floor from the lc/lx, or to take the rear IRS and front suspension and swap those in my car.

Anyone have experience with either option?
 
Why not look at the LS engine? Half the weight, less than half the cost, mega more available in the aftermarket and can make twice the power at half the cost.
 
I know it's not popular around here! But RustyRatRod has a valid point! There's another member on here that's doing it and you should check it out before making any decisions about what direction to go in.
 
If you are putting a hemi in a challenger, there is plenty of room compared to the a-body's.
You can use the stock suspension with power steering, its a bolt in deal.
With all the parts available from Hotchkis you could copy what they have done with their E-max way easier , all bolt ins.



Here is an older thread on an E-body swap, but a good one.

http://board.moparts.org/ubbthreads/showflat.php?Number=3930520
 
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I've seen a few people do the interior swap as well, but not sure I've seen it in an A body before. I think it was a B body Road Runner or something that someone swapped a full dash and seats and stuff in. I think he basically took the LX unibody and cut the factory shell off and replaced it with the classic body as you mentioned.

And while I slightly agree that the LS can be cheaper, the Hemi costs have come down quite a bit in just the few years since I did my swap. I was just getting around to it when the parts were getting more available and everything was pretty much bolt-in. There are some more options out there now and you can do it affordably depending on what your end goals are. Suspension and handling is what's really going to kill you on cost, the engine doesn't have to. I had a full running driving swap for around $5k, and that included the engine, some slight machine work, and headers. Use factory manifolds and that's $700 off already. With more Hemis in the yards now you can probably even get a better deal on engines too (mine dropped an intake valve seat and needed a sleeve, piston, and new head and also came with no wiring or computer). I've seen people get full turn key junkyard pulls for $1500. Add in conversion mounts and whatever transmission adaptation you might want (flexplate or flywheel) and you can probably be driving a swap for $2500 or less.
 
I've seen people get full turn key junkyard pulls for $1500. Add in conversion mounts and whatever transmission adaptation you might want (flexplate or flywheel) and you can probably be driving a swap for $2500 or less.

LS guys are getting full pullouts for $750 and doing entire old school swaps for $1000-$1500

the biggest hurdle for G3 HEMI swaps are the computer and harness
Places like Modern want $1k just for the harness or $2,600+ for the harness & ecu
LS guys out there have the harnesses for a couple hundred and can flash your ecu for another hundred or so

there's power in numbers...
 
No experience with a full swap. Mopar5150 on Lxforums did a full chassis swap. Look him up.

Hemi FTW. I've done a few and like them with the $1300 EFI source computer and harness. 6 wire hookup. Doesn't get any easier than that.

There is no good reason to put an LS in a Mopar. But let's not start that again in this man's thread.
 
LS guys are getting full pullouts for $750 and doing entire old school swaps for $1000-$1500

the biggest hurdle for G3 HEMI swaps are the computer and harness
Places like Modern want $1k just for the harness or $2,600+ for the harness & ecu
LS guys out there have the harnesses for a couple hundred and can flash your ecu for another hundred or so

there's power in numbers...

True, but if you get a stock harness and computer with a junkyard pull you can modify it yourself to remove the circuits you don't need. The only thing you might need in that situation is a flash, which should only be a few hundred.

I'm not denying that the LS is a much bigger market and likely cheaper, I just think the gap has narrowed quite a bit from even just a few years ago. I did my swap around 4 years ago and just finding an engine was hard enough. A lot of places are finally starting to catch up and offer Hemi stuff. There are a few plug and play Megasquirt setups that are roughly the same cost as their Ford and Chevy counterparts now I believe.

Either way I think the engine is actually the cheapest part of building a resto-mod style Mopar. Suspension and chassis setups are pretty serious money. I debated an RMS Alterkation many times, but I bought my car for less than that setup would cost me, and that's just the front suspension setup. The rear costs the same amount, so I'd have twice the value of my car is suspension alone.
 
So, according to Rusty, the LS weighs 250# and produces 790hp for 2K?
Sounds like another 500 horse 350 story to me...
 
So, according to Rusty, the LS weighs 250# and produces 790hp for 2K?
Sounds like another 500 horse 350 story to me...

no
they make about the same HP (LQ9 vs G3 HEMI)
but the cheapest LS engine/tranny pullout I've come across is $500
whereas the cheapest HEMI pullout I've scouted is $1,500
I'd say a "safe bet" L33 with 60,000 verified miles on it can be had for $800
and stuffed into pre-72 metal for another $200 to $500 with OFF THE SHELF parts
I see it done all the time on stevesnovasite.com and 67-72chevytrucks.com

Like we have HemiDenny and Alterkation
they have ChurchBoysRacing and Heidts (and many more) for their front end stuff.

but yeah overall the HEMI swap stuff has come down in price A LOT in the last couple years.
 
Why not look at the LS engine? Half the weight, less than half the cost, mega more available in the aftermarket and can make twice the power at half the cost.

Yeah that is a fact. I looked at doing that exact thing, until I learned about these new Hemis. But yeah at one point I was going to do an LS swap for that reason. Changed my mind though, given that I can get an entire car for about $4-$6 with a hemi, so not bad at all.
 
No experience with a full swap. Mopar5150 on Lxforums did a full chassis swap. Look him up.

Hemi FTW. I've done a few and like them with the $1300 EFI source computer and harness. 6 wire hookup. Doesn't get any easier than that.

There is no good reason to put an LS in a Mopar. But let's not start that again in this man's thread.

Yeah I've looked at all the threads online that I could find pertaining to this swap, including Mopar 5150. Talked with him a bit on the phone about it as well. He had a charger which was a bit different dimension wise than the challenger I am working with. The idea of patching in front and rear suspension is getting more popular, although it may be more fab work, than just putting the floor pan in since it already has mounts.
 
LS guys are getting full pullouts for $750 and doing entire old school swaps for $1000-$1500

I'm coming where you are with a trailer!

The muppets around here want 2k for totaled tahoes and suburbans with high miles.:wack:

There is hardly a cheap 4.8/5.3/6.0 to be found that isnt full of glitter or with cracked heads :-:banghead:

Be nice to see the challenger body laid over a an ex-cop Charger 5.7:blob:
 
Yeah, in my area LS motors are 1400-2200... I got mine for cheaper. =P
 
no
they make about the same HP (LQ9 vs G3 HEMI)
but the cheapest LS engine/tranny pullout I've come across is $500
whereas the cheapest HEMI pullout I've scouted is $1,500
I'd say a "safe bet" L33 with 60,000 verified miles on it can be had for $800
and stuffed into pre-72 metal for another $200 to $500 with OFF THE SHELF parts
I see it done all the time on stevesnovasite.com and 67-72chevytrucks.com

Like we have HemiDenny and Alterkation
they have ChurchBoysRacing and Heidts (and many more) for their front end stuff.

but yeah overall the HEMI swap stuff has come down in price A LOT in the last couple years.

What I was getting at was RustyRatRod said it weighed half as much, and would put out twice the power for half the money. I bought my 395HP 5.7 for $1600CDN with 2000 miles on it. By the time I'm done I'll have roughly 4K CDN into it, headers and exhaust included, and be over the 400HP mark. Chaps my hide when guys start talking excrement out of their anus just for the sake of stirring the pot...
 
IMO, if you want to put an LS into your classic Mopar, that's your business. Do what you want with your car.
However, IMO, you lose your Mopar Man credential. You just can't say you're a Mopar guy or gal if your Dart, Challenger, RoadRunner or what ever, has a non Mopar engine in it.
Sure an LS swap may be cheaper at the very simplest level, but if you are all about cheap and easy etc, you should just hit the easy button and build a Chevy.

Furthermore, this is, infact, the New Hemi Swap section of the forum. If you want to argue the merits of a gm engine swap in a Mopar, do it in the general discussion section.
 
The deal breaker for me using the late model suspension would be the wheels have a positive offset (no dish) . Which puts the hub out further ,track width too wide.
I have seen a couple pics of late model wheels bolted on old muscle , with no dish especially on the rear just doesn't look right.
To me the wheels make or break the look of your ride.
 
Be nice to see the challenger body laid over a an ex-cop Charger 5.7:blob:

Exactly my idea haha. I know they are beat on, but its cost effective and I believe I can handle most of the problems related to that.
 
The deal breaker for me using the late model suspension would be the wheels have a positive offset (no dish) . Which puts the hub out further ,track width too wide.
I have seen a couple pics of late model wheels bolted on old muscle , with no dish especially on the rear just doesn't look right.
To me the wheels make or break the look of your ride.

Wheels were gonna be how I corrected the track width issue. Although, the swaps I have seen this done are all on a 69ish charger, which is wider than my 71 challenger, and those guys used wheel offset to correct the track width issue.
 
What I was getting at was RustyRatRod said it weighed half as much, and would put out twice the power for half the money. I bought my 395HP 5.7 for $1600CDN with 2000 miles on it. By the time I'm done I'll have roughly 4K CDN into it, headers and exhaust included, and be over the 400HP mark. Chaps my hide when guys start talking excrement out of their anus just for the sake of stirring the pot...

There's no need for all that. What I said was basically true. The LS is all aluminum. Is the Hemi? No. I don't know the exact weight difference and I am not getting caught up in looking it up, but suffice it to say the LS is much lighter.

The aftermarket support for Chevy in undeniable. More power can be made dollar for dollar. Argue that all you want, but there's no getting around it.

If I wanted to just "stir the pot" I would have been a lot more obvious than that. I simply stated facts.

But all this is a moot point since the OP knows all that already as he said but still wants the Hemi. More power to him. I hope it turns out nice.
 
Rusty-

A couple facts for you to consider:
-the aluminum LS motors are more expensive
-the 'plentiful' and cheap LS motors are iron blocks, weight is similar to the Hemi
-internal engine components cost the same, LS vs Hemi

I disagree with your claim that more power can be made dollar for dollar. Only at certain build levels is this true (I.e. Stock long block turbo builds). A 'full build' is comparable in both cost and power.

Also, as it sits right now, if you don't have header fab skills, it's cheaper to put a Hemi in a Mopar than an LS in a Mopar.

I totally agree on these facts:
LS more plentiful with more aftermarket support. And it's cheaper to put an LS in a chevy vs a Hemi in a Mopar.

We've done price breakdowns and comparisons on another thread.

Wade
 
Wheels were gonna be how I corrected the track width issue. Although, the swaps I have seen this done are all on a 69ish charger, which is wider than my 71 challenger, and those guys used wheel offset to correct the track width issue.

I wish you luck , that would be a big project completely removing the front ends on two unibody cars, I assume you would even be getting into the firewall also. That would be a lot of fabrication work .
I am the process of doing two hemi challenger projects myself, check out my thread on forEbodies
http://www.forebodiesonly.com/forum/showthread.php?8901-Resto-mod-Challenger
That is the one thing I like about the E-bodies, the hemi fits in their nice ,and with the new borgeson power steering box that gives a modern feel ,Its a bolt in deal for everything with plenty of room.
 
Fair enough. Thanks.

Now, how easy would that have been for our Canadian friend to say rather than go on an insulting tirade?

Yes, I knew there was a difference between the two Chevy engines. I have also done comparisons myself, as I have a friend who is contemplating building one or the other. I think too that total price difference will vary from location to location including parts and machine work.




Rusty-

A couple facts for you to consider:
-the aluminum LS motors are more expensive
-the 'plentiful' and cheap LS motors are iron blocks, weight is similar to the Hemi
-internal engine components cost the same, LS vs Hemi

I disagree with your claim that more power can be made dollar for dollar. Only at certain build levels is this true (I.e. Stock long block turbo builds). A 'full build' is comparable in both cost and power.

Also, as it sits right now, if you don't have header fab skills, it's cheaper to put a Hemi in a Mopar than an LS in a Mopar.

I totally agree on these facts:
LS more plentiful with more aftermarket support. And it's cheaper to put an LS in a chevy vs a Hemi in a Mopar.

We've done price breakdowns and comparisons on another thread.

Wade
 
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