Buick 263 C/1500 build.

RW74

Member
Before you judge me, hear me out.

I just bought a 1991 extended cab 1500 Silverado for $100.

Zero rust, flawless paint and body with a hole in the engine block and a locked up manual 4 speed.

I also recently bought two perfectly good running 263 Buick inline 8 engines and their original transmissions for $500.

A rebuilt 350 V8 would cost me $1200 on the low end and a transmission shop quoted $790 to rebuild the 4 speed.

Given all that, I've decided to put one of the flawless 263 engines and it's transmission in the truck.

I need advice on engine mounts.

The transmission cross member won't be an issue, as I've got one, that I'll be making brackets for, out of a '48 Buick at the salvage yard.

I'm using a Strange 9 inch axle with 2:47 gears, as well, so any engine performance upgrade ideas are welcome, especially if there is any way to install roller lifters to replace the flat tappets.
 
WELCOME!!

I like the straight into the pickup. BUT, it will be cheaper to go back original. You would still have a cheap truck. But what's the fun in that?

The Buick transmissions are for a torque tube drive line. Some kind of an adapter will be needed at the back.

Is there enough room between the firewall and radiator for the longer engine?

I hope you GO FOR IT!

Ben
 
I agree with Ben, stock will be most economical. If I was to try it, I would adapt at the bell-housing to an original transmission.
As soon as you start talking performance upgrades, a Chev 350 is 1/2 the cost. Anything can be done at a cost, including roller upgrade, but you may be looking at several thousand dollars to accomplish something like that alone.
Have you done compression test on the Buick 263 to help confirm that they are in as good a condition as you hope? I have seen some mighty nice looking junk that people have paid a lot of money for...

If you do it, it would be cool!
 
WELCOME!!

I like the straight into the pickup. BUT, it will be cheaper to go back original. You would still have a cheap truck. But what's the fun in that?

The Buick transmissions are for a torque tube drive line. Some kind of an adapter will be needed at the back.

Is there enough room between the firewall and radiator for the longer engine?

I hope you GO FOR IT!

Ben
The Buick engines came with the factory 3 speed manuals.

The cheapest, good running 5.7 TBI with a 4 speed manual, that I could find, was $7500 for the engine and transmission.

That body style pickup was also available with a 4.3 V6.

Ironically, the 263 Buick straight 8 is close enough to the same power as the 4.3 V6 that I wouldn't notice the difference, considering that I've been driving a 2.2 liter Sonoma.

Cubic inches to liters: 263 cubic inches is very close to 4.3 liters.

So, to answer your questions: no.

It would not be cheaper to go back to original.

Yes: there is plenty enough room from the firewall to the radiator, if I put a pusher fan in front of it and leave the fan and fan block off of the Buick engine.

Also, since I've never driven a vehicle that had power steering, for any notable time, I'm not concerned in the slightest.

I have a steering column hub adapter for the truck that is specifically designed for the use of 18-wheeler steering wheels.

I have a solid teak and steel 18 inch steering wheel to put in it and a cobalt blue glass doorknob for the shift lever.

Ever hear of a thyristor?

I'll be putting one on the ground cable of the starter and the trigger wire will only have power when a button is pressed WHILE holding the key in the start position.

The starter solenoid will click, then, pressing the button will allow the power to reach ground through the thyristor, engaging the starter.

We all know how smoothly these straight 8's run.

That, coupled with the nearly dead silent exhaust that I'll be using, will make anyone think that it's not running at all.

I'm not having someone ruin my starter by turning the key with the engine running.
 
I agree with Ben, stock will be most economical. If I was to try it, I would adapt at the bell-housing to an original transmission.
As soon as you start talking performance upgrades, a Chev 350 is 1/2 the cost. Anything can be done at a cost, including roller upgrade, but you may be looking at several thousand dollars to accomplish something like that alone.
Have you done compression test on the Buick 263 to help confirm that they are in as good a condition as you hope? I have seen some mighty nice looking junk that people have paid a lot of money for...

If you do it, it would be cool!
Fortunately, I've never cared about performance upgrades and I do know how to make camshafts, crankshafts, etc.

As far as "economical" and you're referring to efficiency vs. cost, I'm using a Strange axle with 2:47-1 gears.

The OEM GM V6 found in other 1991 Silverados is 263.4 cubic inches, 140hp.

The 1991 Silverado is 4,703lbs (curb weight) with the 5.7. and 4 speed manual.

The Buick 263 is 120-124hp stock.

A 1951 Buick Special is 5,744lbs without a transmission and engine in it.

My truck will be lower weight than stock.

I do have a Master's in mechanical engineering, majored in obsolete techniques and parts fab. I minored in machining.

I COULD build one of these engines but, honestly, it wouldn't be a true GM engine and that would bother me more than putting a Ford engine in a Sunbeam Tiger.
 
Do you intend to use the Buick transmission?

Ben
Absolutely.

I won't be towing anything with the truck, so I'm far from concerned about it's longevity.

Since I'm painting the truck with actual 1950's Buick pigments, it only makes sense to redesign the interior with this in mind.

Even so, I did see a picture of a 1952 Buick Roadmaster pulling a camper trailer.

By the way; your username... Is that a Star Trek reference?
 
LOL! Nothings o exotic. Oldest of eight children.

I have a warmed up 263 in my 1950 Special. Three speed original transmission. A 3.36/1 rear gear. I have to slip the clutch some on take off on a slight grade. I can't imagine doing so with a 2.47 gear.

Ben
 
LOL! Nothings o exotic. Oldest of eight children.

I have a warmed up 263 in my 1950 Special. Three speed original transmission. A 3.36/1 rear gear. I have to slip the clutch some on take off on a slight grade. I can't imagine doing so with a 2.47 gear.

Ben
I see.

Your Buick curb weight: 2020 kg / 4450 lbs, whereas the 1991 C1500 is 4,403 with a 5.7 V8.

I think that one would originally have been 4,368lbs with a 4.3 V6. I didn't check the V6 curb weight, so it's merely a guess.

A standard cab, short bed is 4,000lbs.

The TBI 5.7 V8 and the Buick 263 are both 600lbs.

Tires: LT235/75R15 Americus Commercial 10 ply (28.9 inch diameter)

Final drive ratio (with external overdrive gearbox): 0.63-1

Target speed: 70mph

=

Engine RPM: 1260

As light as the truck is, compared to the Buick, especially with a sloped bed shell "213lbs" (imagine a hatchback pickup truck) it should be able to cope easily enough.

I'm also going to tear into one of the engines for a full mechanical inspection to see if I can add roller lifters, titanium pushrods, have a machine shop make billet steel connecting rods, billet steel pistons, etc.

I'll definitely be looking into roller rockers.

I just need stock rocker info, such as lift ratios, compatibility, etc
 
That generation tbi 5.7 which is rock solid dependable around here will run you roughly $700 +/- with around 100k miles. I find it hard to believe that price unless you're having it shipped from space. Vehicles tend to rot away here long before the drivetrain wears out. Guys here are tripping over each other to get their hands on the LS based powertrains so the conventional engines are all but forgotten. Myself I would go for one of that eras 7.4 or 8.1 V8's and build myself a monster but that's just me. Your project your choice.

Have you measured firewall to radiator to check for fit. No truck from this era is designed for an inline engine and I'd think things would be tight. You'll probably have to mount the radiator to the outside where an AC condenser would go.

I wish you luck as you're going to have a lot of expensive one off engineering to accomplish. Keep us posted with your progress.
 
That generation tbi 5.7 which is rock solid dependable around here will run you roughly $700 +/- with around 100k miles. I find it hard to believe that price unless you're having it shipped from space. Vehicles tend to rot away here long before the drivetrain wears out. Guys here are tripping over each other to get their hands on the LS based powertrains so the conventional engines are all but forgotten. Myself I would go for one of that eras 7.4 or 8.1 V8's and build myself a monster but that's just me. Your project your choice.

Have you measured firewall to radiator to check for fit. No truck from this era is designed for an inline engine and I'd think things would be tight. You'll probably have to mount the radiator to the outside where an AC condenser would go.

I wish you luck as you're going to have a lot of expensive one off engineering to accomplish. Keep us posted with your progress.
The Buick 263 engine cylinder head is 31¼ inches long, a 292 L6 head is 35 inches long and I've seen 292 engine swaps into 1988 to 1998 models of that body style.

The fully assembled 263 engine will be about 34-35 inches long.

I'll be using the original Buick 3-speed, which is easily the single smallest manual transmission that I have ever seen used in a full-sized sedan of any year.

The bell housing will clear the firewall and, if I have to, I'll bow the radiator to make it fit.

I've bowed radiators before and, no, I won't do it to the OEM radiator in the truck.

I have a new copper radiator, short enough to fit between the upper and lower core supports, and a bow press that I made specifically for radiators.

I've never had a bowed radiator leak once.
 
The Buick 263 engine cylinder head is 31¼ inches long, a 292 L6 head is 35 inches long and I've seen 292 engine swaps into 1988 to 1998 models of that body style.

The fully assembled 263 engine will be about 34-35 inches long.

I'll be using the original Buick 3-speed, which is easily the single smallest manual transmission that I have ever seen used in a full-sized sedan of any year.

The bell housing will clear the firewall and, if I have to, I'll bow the radiator to make it fit.

I've bowed radiators before and, no, I won't do it to the OEM radiator in the truck.

I have a new copper radiator, short enough to fit between the upper and lower core supports, and a bow press that I made specifically for radiators.

I've never had a bowed radiator leak once.
I'm hoping you go ahead with this project. It sounds like fun. Challenging, complicated, tricky, maybe, but fun. I have two six cylinder Chev engines in old cars - a 292 in a 53 Pontiac, and a 250 in a 40 Buick. Both have automatic overdrives, a 700R4 in the Pontiac and a 200 4R in the Buick, and both have 2.73 rear ends. So I have a head gasket for the Chev engines hanging with one for the Buick 248/263, and the Buick one, I'm sure, is longer. Are you sure you wouldn't be happier in the end with a 5 speed manual? I like overdrive. (The slanted print is an accident. I don't know how I did it or how to fix it.) I look forward to hearing more, and seeing some pictures. The truck sounds good.
 
I, too, hope you proceed with the Buick engine. Agree with PICTURES . Especially of the mods on the shift linkage.

Ben
 
I'm hoping you go ahead with this project. It sounds like fun. Challenging, complicated, tricky, maybe, but fun. I have two six cylinder Chev engines in old cars - a 292 in a 53 Pontiac, and a 250 in a 40 Buick. Both have automatic overdrives, a 700R4 in the Pontiac and a 200 4R in the Buick, and both have 2.73 rear ends. So I have a head gasket for the Chev engines hanging with one for the Buick 248/263, and the Buick one, I'm sure, is longer. Are you sure you wouldn't be happier in the end with a 5 speed manual? I like overdrive. (The slanted print is an accident. I don't know how I did it or how to fix it.) I look forward to hearing more, and seeing some pictures. The truck sounds good.
Regardless of what I'm building, I only use the transmission that belongs to the engine, not the vehicle.

With a 2:47-1 ratio differential gear set, I shouldn't need overdrive.
 
Can we upload videos? I've got motion recording security cameras that save to a bank of ten 1TB SD cards and, at 9.75TB, the first SD card in the series gets formatted in a full loop record-over setup with 4k 10k/mp movie quality cameras.

Before you ask, no.

I'm not wealthy. A recording studio went belly up and was selling the eight cameras for $800 total. Each one, new, costs $5,785 and the producer is a family friend of my uncle-in-law.
 
Last edited:
The mechanic that I work for removed both 263s, with stick shift transmissions, out of the cars and that's what I have.


.dub ,enim sa doog sa si sseug ruoY

"EDIT"
Sorry..

Your guess is as good as mine.
 
Back
Top