Swaps Other than LS or LT

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1STLS1

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I am in the middle of doing a frame up on my '87 GMC short bed step side. My original intention was to drop a used Goodwrench 5.7 and reman trans I have sitting around and use it for my daily driver for the next couple years. Recent fuel prices have made me begin to rethink this a bit, 14 mpg isn't very attractive. I could do cam, heads, chip and get 17 mpg. A LS or LT swap may do a little better.
Anybody heard of somebody dropping a new Camaro 2.0 turbo and 8 speed in one? Or a 3.0 diesel with a 10 speed? It's going to be similar money as a LT swap and would have to get better mileage along with performing better than the old 350 TBI.

Any better ideas for a max fuel economy square that runs decent? Old 6.2's got great mileage but were just too darn slow.

I saw the discussion about dropping a Ford Ecoboost in one, I just couldn't do it. Yeah, great engine, just couldn't do it to an old square.

Thoughts?
Ideas?
$10K budget with some flexibility?
 

ulm4lyf

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If you could manage the 3.0 Duramax with the 10 speed trans that would be sweet. I have that setup on my 2021 4x4 1500 and over 27,000 I'm averaging 25mpg.
 

1STLS1

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If you could manage the 3.0 Duramax with the 10 speed trans that would be sweet. I have that setup on my 2021 4x4 1500 and over 27,000 I'm averaging 25mpg.
Cool some real world feedback. The 2 wheel drive and lighter weight may do even better.

That 3.0 and 10 Spd is available much less expensive than any of the LT combinations. If I have some time this week I will call some places and see if anybody has swapped one yet or what the challenges are.
 

ulm4lyf

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There are several videos on Youtube where people have put Cummins 4bt engines into squares. If I had the money, I think that I'd look into that.
 

MattCone_TX

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Curious how you'd handle the gear selection and indication on the 10 speed. I have a 5.3 LS in my 86 but i'm running a 700R4.
 

1STLS1

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There are several videos on Youtube where people have put Cummins 4bt engines into squares. If I had the money, I think that I'd look into that.
I was an equipment mechanic for a number of years and have worked on, well leave me rephrase that, changed fuel filters on 4BT for a long time, they just don't break. They are anvils, you can't hurt them. They can be modified to work well, get good fuel economy, make great power. I just want something more refined and modern.
 

1STLS1

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Curious how you'd handle the gear selection and indication on the 10 speed. I have a 5.3 LS in my 86 but i'm running a 700R4.
One vendor I saw uses a cable set up to operate the column shift for the 6, 8 and 10 speed GM transmissions, lots pretty simple.
 

eskimomann209

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One vendor I saw uses a cable set up to operate the column shift for the 6, 8 and 10 speed GM transmissions, lots pretty simple.
Do you have a link for this?
Hell I’d be interested in seeing it.
I use the 4L60e in my stock column but I just don’t or can’t go into 1st gear without it throwing off my indicator.
But I’d be interested in a cable that can be fine tuned.
 

RecklessWOT

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How about a big block? Lol

I was unaware they ever put 2.0 turbos in Camaros, I knew they offered the iron duke for a few years but didn't think there was a performance option and they were all just dogs that people bought to look cool in a Camaro and ignore performance. Also I feel like an LT1 swap would be far cheaper than any LS or other modern diesel swap with a 10spd transmission etc. As they're still not really popular I feel like an LT1/LT4 could be had for a few hundred bucks from a junkyard and would still bolt up to a normal transmission. There's some simple electronic stuff going on but nothing compared to an LS swap, and being a little more of an "old school" real 350 it is like 1,000 times cooler than any LS garbage someone might toss at one of these poor trucks
 

SquareRoot

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THIS!
I have the Duramax version of this in my AT4 and it gets 35 mpg average, sounds cool as hell and tows 7700 lbs.
 

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1STLS1

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Do you have a link for this?
Hell I’d be interested in seeing it.
I use the 4L60e in my stock column but I just don’t or can’t go into 1st gear without it throwing off my indicator.
But I’d be interested in a cable that can be fine tuned.
I don't know how they view outside vendors on this board so I will just ask for forgiveness if I'm wrong... :)


The guy that runs that site is really cool and super knowledgeable about the swaps. He took the time out to answer a bunch of questions I had when I considered a LT1 swap a couple years ago. He also does wiring harnesses and tuning.
 

oldretiredafguy

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How much do you drive on a daily basis that you're so worried about gas mileage? None of my business, but part of the attraction about driving our old squares is the looks from mere mortals, plus I've never met a woman who doesn't like a bench seat so they can cuddle up against the lucky driver/owner of said square. I know Phoenix has grown since I lived there in the mid 70's, hopefully it hasn't gotten as bad as LA, or DFW, or God help us like Bangkok.
 

eskimomann209

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I don't know how they view outside vendors on this board so I will just ask for forgiveness if I'm wrong... :)


The guy that runs that site is really cool and super knowledgeable about the swaps. He took the time out to answer a bunch of questions I had when I considered a LT1 swap a couple years ago. He also does wiring harnesses and tuning.
Looks like they have some cool items in there. Thanks for that.
 

1STLS1

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How much do you drive on a daily basis that you're so worried about gas mileage? None of my business, but part of the attraction about driving our old squares is the looks from mere mortals, plus I've never met a woman who doesn't like a bench seat so they can cuddle up against the lucky driver/owner of said square. I know Phoenix has grown since I lived there in the mid 70's, hopefully it hasn't gotten as bad as LA, or DFW, or God help us like Bangkok.
A honest answer is it most likely doesn't matter. I think I would drive it more often if it wasn't the least fuel efficient. Like today, I have a beater '05 Ranger that gets 21 mpg no matter how I drive it and I tend to drive more because it gets the best mileage. Just something in my personality, I'm cheap
 

TotalyHucked

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I think it'd be cool as hell to do something different. Mine is LS swapped cuz that's what I'm familiar with and is pretty simple/budget friendly. The 3.0 Dmax/10-speed would be awesome. I bet you'd get 30+mpg, I get 22 with my cammed LS
 

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