1989 R3500 blown head gasket and cracked head

[skycop530]

I purchased a truck a few months ago that I used to own in my early 20's. A 1989 R3500 crew cab dually. It's kind of a king without a country. It's a square body but with an engine setup of the late 80's body style change...TBI. So when I order body parts, I have to order pre 1987. With engine parts, I have to go with TBI. Ok to the point. I love this truck...but it was sent from the factory with an underpowered TBI 350. The good news is the head gasket blew and in the process cracked the head. So I can replace it for something with some testeeze. So, I have been racking my brain with what I'm going to replace the worn out 350 with. I thought about diesel...and that's the route I would really like to take...but I can't eat the cost at the moment . I really don't want to go all out 454 due to operating costs. What about the GM HT383? Has anyone put one of these engines in a TBI truck? I know they are meant for carb setups. Any other ideas from the savy engine swappers? I'm confused as to what would be the route to take...I've been my own worst enemy over analyzing this project. I live in TN so I don't have an emission test to pass. Just looking for ideas...

[SCOTI]

They make a specific HT383 for late model TBI swaps. Sounds like what you're looking for....
http://paceperformance.com/i-6255415...-r-engine.html

[skycop530]

Thanks. That looks like a good option.

[Goldfinger]

Vortec swaps seem to be more common and since its already tbi it may be easier. they can also be turned for power or performance whatever you need that day. I've been looking into one however i have to wait for my 305 to die, unfortunately they last forever.

[80SPORT]

The 383 crate motor would make a nice upgrade and all your external components would work.

The 383 is a vortec so you would need to change your intake;the ht383e is set up for for a 96+ truck but it would work if you used the intake from a 96+ vortec unit.
You could also change up to the overdrive trans as used in the 1991 trucks.

I had a 91 dually crew with the 454 efi/overdrive trans ...never should have sold it.

[SCOTI]

Originally Posted by 80SPORT

The 383 crate motor would make a nice upgrade and all your external components would work.

The 383 is a vortec so you would need to change your intake;the ht383e is set up for for a 96+ truck but it would work if you used the intake from a 96+ vortec unit.
You could also change up to the overdrive trans as used in the 1991 trucks.

I had a 91 dually crew with the 454 efi/overdrive trans ...never should have sold it.

EFI as in TBI or ??

[ghettoluxury]

Just go with a 6.0l and dont look back!

[b454rat]

I keep hearing about going from a 350 to a 454, most people don't want to do it because of gas mileage. Won't they don't realize is your trying to move a 7k+ truck with a small block, it's gonna be working no matter what. At least with a 454 it won't be working as hard.

Little story. I had a 97 2500HD with a 454. Ext. can long box, 4wd, auto, 4.10s, really nice truck. I never really checked, but I think once I figured I was getting 12-13 with it. A guy I used to work with had a 2500 6 lug auto with a 350, basically the same as my truck, he was getting 10 if he was lucky.

Another guy had a 2000 crew cab short box that I wanted BAD, and asked him about it. Said he was getting 8-9 with the 350 auto, on the highway unloaded. And then it wasn't going very fast, said it was working to keep it going.

My 454 would pull any hill without downshifting, couldn't even tell if if was working hard or not. (course this was before my buddy killed it)


And when you go for parts, make sure you tell them it's an "R", not the "C" or "K". I've always gotten the right parts.

[old Rusty C10]

i cannot add to your engine dilema but i certainally gree with you that is one gorgeous truck!!

[tucsonjwt]

Having owned both 350 and 454 squares, I have an opinion on both. My 3 squares were all 3/4 ton trucks. In my experience, when you have a 3/4 ton truck or heavier, you won't get good gas mileage regardless of the engine, unless you have a diesel, which has its own issues.
It is true that parts for a 454 are more than a 350 and more difficult to find. However, standard repair parts are not much more. Unique engine parts can be a challenge, but if you have the time to search for used parts they are not more expensive. I have one quirk in my current 454 - I have had trouble finding a crank pulley (no longer sold by GM), so I finally purchased a used one on Ebay for $65. (My crank pulley somehow got a loose bolt and flew off, tearing it up - this has never happened to me before and probably never will again.)
The best engine/trans combo I have had is a 454/TH400, but I think a 454 with overdrive transmission (700R4 or newer) would be best.
Because 454s have a bad gas mileage reputation they are easy to find. They are not cheap because of hot rod and boat demand, but you can get a whole vehicle with a 454, take out the engine/trans and sell the rest for $$. I would not be surprised if you could get an old 454 vehicle, take out the engine, and sell the remaining parts for break even or better. A "free" 454 beats a built 383 any day in my book.
I don't think you will get more than 10-12 mpg whether your have a 350, 454, or 383.
How many miles will you drive this truck per year? Unless you drive a lot, a few mpg difference will not justify spending big $$ in a different engine.
I will say that a properly tuned 454 is a dream to drive. With a properly adjusted Qjet carb I have achieved 11-12 city mpg. 14 mpg on a rare highway trip. But predicting mpg is a guesswork at best. Good luck.

[skycop530]

Thanks for all the info. My thinking on the 383 was that I would get BB power from an engine that would bolt in place of the 350 block without too much extra work. To my knowledge, I would have to change out all kinds of components to retro fit a 454. It's really not a fuel mileage thing. I realize that the weight and a square nose severely limit this truck as far as fuel effeciency. This truck is heavy to say the least...that's why I originally wanted to throw a diesel under the hood. An overdrive trans would be nice in place of the turbo 400, but then I would need a controller for the 4L80e. I don't trust the 700r4 in towing applications, which this truck has and will continue to see. In all honesty, I really prefer a manual and if I went with a trans swap, it would be converted to a nv4500. Thanks again for all the input.

[skycop530]

Originally Posted by old Rusty C10

i cannot add to your engine dilema but i certainally gree with you that is one gorgeous truck!!

Thank you sir!