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Discussion Starter · #1 ·
I've got an 1984 Chevy half ton, currently equipped with a 305 and th350. 4wd also. My question is can it fit a 454 BBC? Or is that too much? I really like the idea of the big block, but I'm not sure it will fit. I'm guessing the transmission would need to be upgraded to a th400 too? Any advice is appreciated. Thanks.
 

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Discussion Starter · #3 ·
Well I don't wanna have to rebuild the front clip and firewall. I'm sure the motor mounts would never match up, but other than that would it be pretty straight forward?
 

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ROB
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Yes it fits but I might as well be the first to tell you that it isn't worth it anymore. If your going to swap engines to upgrade then upgrade to a ls engine.
 

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It will fit as the big block was an option on these trucks. You will need to upgrade your cooling system as well as the tranny and the stock 10 bolts wont last too long behind a healthy 454.

As stated above, the LS swap is a better way to go in today's world.
 

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Discussion Starter · #6 ·
Well as it stands right now, I'm not very well funded for this project. I know the 70's 454's are really reliable and semi common. How much can be done with those compared to an ls? And what would be a decent ls engine for drag racing and mudding?
 

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Heres my example:

I bought a running 71 402BB that had good oil pressure but a slight miss for $300. The slight miss turned out to be a bad valve guide. Since I was going to have the heads off, I decided to freshen up the motor, since it is over 40 years old and I have no history on it. Bores were surprisingly clean and the crank was in good shape. So at this point:
$300: purchase price
$700: New solid cam/lifters, New stainless valves with replacement guide and correct springs, Felpro gasket Kit, ARP head bolts, New timing chain, new rings, new bearings, and new oil pump.
$200: Used aluminum intake, rebuilt Holley 650 DP
$100: Used 4 core radiatior

Dont forget that you also need the big block accessory brackets.

I dropped this in my 76 K5. It wieghs 200 to 300lbs more than the 350 that I pulled out. It will probably make 325 hp and around 400 lbs of torque.

You could have a running driving fuel injected 5.3 that makes similar power but weighs 300 lbs less for about the same price.



 

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HABS SUCK!!
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Well as it stands right now, I'm not very well funded for this project. I know the 70's 454's are really reliable and semi common. How much can be done with those compared to an ls? And what would be a decent ls engine for drag racing and mudding?
Since this is the second thread you've posted about drag racing a truck, are you talking about on asphalt or in mud? You're going to be thousands and thousands invested no matter which route you choose. Trust me, slapping together a bunch of junk will lead to horrible end results. I've done it with SBC's twice.
 

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Discussion Starter · #9 ·
Since this is the second thread you've posted about drag racing a truck, are you talking about on asphalt or in mud? You're going to be thousands and thousands invested no matter which route you choose. Trust me, slapping together a bunch of junk will lead to horrible end results. I've done it with SBC's twice.
Well I'd like to drag race on asphalt and tool around in the mud. Also to have this as a truck to show off and appreciate.
 

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HABS SUCK!!
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I think if I was in your shoes I'd forget about drag racing. Throw a healthy and already running SBC in the thing and beat the bag out of it. Later in life buy a notchback and an lq4 and go fast. It's going to be impossible to do both with a tank on a low budget.
 

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Mmm Sandwich
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HABS SUCK!!
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Why? It's cheaper to run fuel injection. Plus going that route you loose a lot of the benifits of even putting it in in the first place.
All depends on which parts you use, you buy an LSXR for a FI motor and carb is cheaper. I'm putting a holley 950 hp on mine.
 

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Why? It's cheaper to run fuel injection. Plus going that route you loose a lot of the benifits of even putting it in in the first place.
Not when putting it in an older vehicle. Custom wiring harnesses are not cheap. You still have all the benefits of the LS design, nothing wrong with an Edelbrock carb.
 

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Mmm Sandwich
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Not when putting it in an older vehicle. Custom wiring harnesses are not cheap. You still have all the benefits of the LS design, nothing wrong with an Edelbrock carb.
If you are paying people to do it. There is so much info available to do it yourself. Plus having a harness redone can be done for under $300. Which is still cheaper than a new carb, and intake.

Fi is far easier then most make it out to be
 
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