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My son's build. '72 Chevy

6872xtc

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THis takes a little backstory, so here goes. My Dad bought this truck brand new, it was a C10, we put it in a K10 frame back in '92. It had 290K or so on it then. It is not rust free as we used to live in Nebraska, but it is not terrible. It now has a used 400 smallblock in it with all the factory brackets and such. The engine only had 72K on it when we put it in around '86. So it has had trans issues for a while and my Dad refused to spend the money to fix it, so my son bought it from his Grandpa since I already have too many trucks. (what my wife says).
I am trying to convince my son that he should leave the truck as a smallblock set-up and not buy an LS. I say that it still looks like a '72 Cheyenne and he should leave the engine stock looking as well as the dash. I think I have convinced him on the stereo, but the LS engines keep tempting him.

What do you all think???? :whistle::popcorn:

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6872xtc

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I don't have a problem with some changes to the outside, and he doesn't wan to do much there. I keep telling him to use the money that he would use to buy and install an LS, on other things. We can even play with building that 400 if he wants. But why change fuel system, brackets, exhaust, and all. I know it is HIS truck now, but I told him that it will always be MY Dad's truck to me.
 

rebelgregory

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Wish I could help. I still have the original TBI in mine, but at the first good excuse, I'm going 6.0 LS. They're more powerful, lighter, better mileage, and more reliable. What's not to love?

If it was a full restoration job, then maybe. But for a driver, modern drivetrain under old iron is a win if you ask me.
 

olivedrab

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The main reason I suggested the swap was I seen you guys switched out the original frame and engine. I do see your point though about it being your dads truck.
 

K85 Octane

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Oh snap!! lol
Father and son throw DOWN :D


The LS swap would be much easier with a 2wd, but the 4wd will take more work. Just depends how often it gets driven. I wouldn't want to DD my 400sb blazer, that would get old quick
 

sweetk30

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cost of doner ls swap to even just a 5.3 is good these days . and 300 hp stock is nice . guys say tuning them stock can get another 40-50 hp also .

fuel mileage alone will pay for the swap in short order .

also it can be swaped back to reg old sbc real easy with saving the old parts . its all bolt in for the most part these days .

and in my opinion best of both worlds .

my 2wd build I got no motor / trans . looked it over and for the cost of a good crate engine and still carb I said screw it . I got complete take out every thing I needed from the doner 5.3/4l60-e and even drive shaft all under 100k miles delivered with warrenty for 2200 bucks . and prices are even lower now if you look around.

guys on ls1tech are saying 17-19mpg in there stuff . 1 guy has 64 impala wagon with 4.10 rear and gets 17.5mpg highway . other guy has 2wd c-10 and just averaged 18.5 on 200 miles highway trip and was even playing with it on the trip .
 

6872xtc

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We have even talked about holding onto to all the old parts, but I think that's a lot of stuff just sitting. I am not sure how much he will drive it before he decides that a standard cab is kind of small. Maybe I'm coming up with reasons??? But he is 6' tall at 15, and I think he will want some more room for passengers and stuff at some point. I guess I have mainly spent too many years around that truck with that smallblock under the hood. I don't really care that my Dad and I changed the frame, trans and all, I know my son would like to put a short lift on it someday, (he likes the look, and he likes the ride of my SWB with ORD fronts) and I think that is fine as well. This probably boils down to my stubborn brain. :doah:
This is also agitated by the fact that I found a '04 4wd Tahoe that got rolled for a grand...
Thanks for the replies.
 

flynhawaiian

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Thoughts

That is a good looking truck.

What kind of shape is the motor in? If it is in good shape could you just fix the transmission and drive it? If both of you decided you still wanted an LS motor you could swap it in using the fixed transmission. If you decided after that you wanted a newer transmission you could add one and deal with stuff like cross members and driveshafts without worrying about motor mounts, fuel system, etc.

Another plus would be you could drive it while you got all the LS stuff together and then you would also have an extra known rebuilt transmission at the end of it all.

One last thought, when I was 15 I wanted every cool truck thing I saw. If he decides the truck is not for him you may then be stuck with something you don't want.

I recommend fix it, drive it and then change what you don't like or want. It is easy to envision the perfect truck, but I think there is something to be said for getting there in steps rather then trying to build it perfectly the first time. Another concept I didn't understand at 15.
 

Metrodps

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I have a solution.... Buy a Blazer body that has no engine. Then you guys can do an LS and keep dads truck. Hreat father and son time.
Would love to have my fathers 72 c10
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Or even this one. Fathers die to soon.
1937chevymixed.jpg
 

diesel4me

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I'm no purist,but I agree...as I've aged,I have found my desire to make things"better" often just creates a lot more work and problems....its bad enough replacing an engine with an identical one ,"upgrades" require fabbing,more effort,money,and patience..none of which most 15 year olds posess..

Also if its already somewhat rusty,that also enters into the equasion--do you want to invest 3 grand and a ton of work into a truck that will soon require a lot of body work too?...the truck would be worth more with an "original" engine to most collectors (they did have 400 SB engines that year factory I believe)...

I liked the 400 SB I had,probably the best small block chevy engine I ever owned ,that I put in my 77 GMC from a 78 Burb..was no worse on gas than a 350,had more guts,and rivaled a '74 454 I had in the truck for power and low end torque,yet weighed less..
 

6872xtc

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Yea, I talked to Lawrence on that blazer the other day. I was unable to help him out as I had a trip to Denver for family and already somewhat committed on the Tahoe...( I need more money for toys!!) The engine in the '72 I believe to be in decent shape still. We woke it up some already with a little basic maintainence. (Dad can't hear leaking vacuum hoses over the exhaust anymore) I think my son will be pleased if we get some of the rust fixed, swap the TH400/203 out to a 700R4/ 208, might let him have my 241.. That keeps the speedo working simply instead of a spendy driver to convert VSS to mechanical.
I definitly agree that he may get frustrated if he can't drive it enough due to too much down time.
 

6872xtc

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I would imagine it was difficult for you to type that post with tears in your eyes from laughing so hard!!! :haha::haha::waytogo:
 

Stomis

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Well I personally happen to think you're on the loosing side of this argument lol. An LS swap can be a really great way to go if you're just looking for something to drive. But also consider that on the other hand if you're looking to do a fresh, brand new build they can get pricey if you're not careful.

Also one thing to consider is you can find those kind of fuel mileage numbers coming from cars and trucks with holley, fast, and edelbrock "carb" style fuel injection systems on them too. Its not necessarily the engine itself, although Im sure there are some characteristics of the LS engine that contribute somewhat to better gas mileage but personally in my project I'll be keeping the small block and converting to fuel injection, possibly even coil on plug on a small block. Simply because this stuff can be ported over to a big block in the future. You certainly cant get 600+ cubes from an LS motor and you can get the same amount out of a small block.
 

super k

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I think people jump too quick on the LS band wagon. That 400 is a great engine for a '72. The SBC is just as great as ever. Let's not forget it's the engine that put GM trucks in front of Ford and Dodge and let's not forget virtually all hot rods for many decades,let alone on the winning race cars of all forms. Not dissing the LS,just saying a 300 hp SBC is a simple accomplishment and one who's time will never pass just because something else came along.
I sold it to my friend,but the '72 K/20 Custom Deluxe Highlander Custom Camper I had ran a SBC400/4spd/No-Spin 4.10 drivetrain and I feel it was an perfect set up. The truck ran 315/75s w/6" EZ-rides with the frame down completely rebuilt. In original paint with an exceptional list of options I feel it was the only way to go keeping under the hood looking factory. That truck had all the torque you ever needed. Enough to roll that truck along with a feather touch on the gas peddle. It felt like it could go anywhere in any gear and no need to mash the pedal. It got a consistent 12.5 mpg no matter where it went. I even put the very unpopular white spoke wheels to keep that "straight out of the '70s nuthin fancy oh that old thing?" look,at least until it got restored. It was just too special to do a dime a dozen LS swap in. Some things deserve to be preserved,not to mention little benefit gained in changing. The older trucks are so easy to keep going and they'll get you home no matter what... And Chevy made an engine badge just for the SBC400...heh heh

 
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Stomis

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I think people jump too quick on the LS band wagon. That 400 is a great engine for a '72. The SBC is just s great as ever. Let's not forget it's the engine that put GM trucks in front of Ford and Dodge and let's not forget virtually all hot rods for many decades,let alone on the winning race cars of all forms. Not dissing the LS,just saying a 300 hp SBC is a simple accomplishment and one who's time will never pass just because something else came along.
I sold it to my friend,but the '72 K/20 Custom Deluxe Highlander Custom Camper I had ran a SBC400/4spd/No-Spin 4.10 drivetrain and I feel it was an perfect set up. The truck ran 315/75s w/6" EZ-rides with the frame down completely rebuilt. In original paint with an exceptional list of options I feel it was the only way to go keeping under the hood looking factory. That truck had all the torque you ever needed. Enough to roll that truck along with a feather touch on the gas peddle. It felt like it could go anywhere in any gear and no need to mash the pedal. It got a consistent 12.5 mpg no matter where it went. I even put the very unpopular white spoke wheels to keep that "straight out of the '70s nuthin fancy oh that old thing?" look,at least until it got restored. It was just too special to do a dime a dozen LS swap in. Some things deserve to be preserved,not to mention little benefit gained in changing. The older trucks are so easy to keep going and they'll get you home no matter what... And Chevy made an engine badge just for the SBC400...heh heh


Lol its hard to put a SBC together and not get 400hp now let alone 300. Its gotten really simply. The LS engines have their advantages, especially given bolting on the fuel injection.
 
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