1969 gmc 2500 2wd

[littledeuce2]

Hi Guys/Gals
1st post and I something I want to share with you. I dont own a 69 GMC but am working on one for a customer. It seems that most of my buddies have 67-72 trucks and i'm sure I'll end up with one sooner or later but I just had to let ya in on this.

Kenton (my customer) came to me with what started as a basic re-seal on the 350 engine and a new set of tires. Fair enough. I pulled the engine, found broken engine mounts and the engine bay was disgustingly dirty. 140,000+ miles on the truck. It has been repainted once and it was to only freshen things up as truck is in great condition.

Upon a visit from Kenton, we went over a list of things extra he wanted taken care of. And at the time we discussed sending the engine out to be re-rung. So off to the machine shop it went. Days went by and I received a phone call from the Machine shop manager. He asked if I knew what I had. Kind of confused I answer " of course...a 350..?" Well he says its not just a 350, its an LT1, steel crank,forged pistons etc.. WoW! I'm onto something here! Immediately I call Kenton to let him in on the news and get some background info on this truck. His father bought it from the 1st owner who apparently worked for GM. The truck came with the engine according to this fellow who ordered it. Kenton and his Dad remembered being told something unique about the truck way back when but didnt think much of it.

I'm posting a few pics of the truck and some engine pics. I will get a better pic of the front deck #'s on the engine.

As it turns out, I ended up pulling the inner fenders and the rad support. They were sent out for blasting and paint. We prepped the frame and pile of other parts.

I'm looking for some info. How many trucks came like this? Was the LT1 and option back then. I would guess its pretty rare as I've never heard nor seen a truck like this to have such a power plant.
It came with a 4 core rad. original to the truck. It has no a/c. the a/c trucks only came with the 3 core from my research. It has 4 wheel drum brakes. Turquoise in color, turbo 400 trans.

[littledeuce2]

BTW the frame and suspension has since been repainted the mat black its supposed to be

[littledeuce2]

Hopin for some info

[too much stuff]

It looks to be a hi-perf 327 or 350 engine for pass. car applications. I can't make out the code on the front of the block, and the date casting will narrow it down some. It was used from 68-74. I would assume it was a transplant at some point in its life.
Nice, clean looking truck.
Eric

[littledeuce2]

Its an LT1. I have run the #'s and so has the machine shop. All the factory bracketry, right down to the original vac advance hose..this engine has never been changed. We pulled out the build sheet...in more than a few pieces from under the seat. Its being put together like a puzzle. We're are looking forward to seeing whats left.V0827XD I believe is the no. I'm not at work right now.

Todd

[68350]

XD 1969 350 turhydro - 255 4 C-10 to 35

It appears to be the original 255 horsepower 350 for the truck. XD decodes above to a 1969 350 with an automatic for pickups. Not an LT-1 out of a camaro or anything. Hope this helps.

[LockDoc]

-
V0827 = Flint, August 27th

RPO XD
FY 1969
CID 350
APPL Turbohydro
VIN
HP 355
BBLS 4
BODY/COMMENTS C-10 to 35

LockDoc

[littledeuce2]

The engine came with 172/150 truck heads mounted on a short block of forged pistons,pink rods and a steel crank...all std/std. After pulling this all apart and seeing OEM gaskets, and everything where its supposed to be. I'm finding it hard to believe its not original. Hmmm..... I want to beat this to death. Thanks for your input guys.

I think when ya worked for the General back in the day, if ya knew someone at the factory or perhaps even someone influential you could get what you wanted. I'm not a stranger to the classic scene, Im a Nova Freak and have been since the day I could hold a wrench. Just to give ya some insight.

Todd

[littledeuce2]

Could the t400 with the electric kickdown not be had in 69?
Lol! I seem to be editing every post to add...
Can you please post links to the number info

Thanks

[too much stuff]

The TH400 was pretty common in 69 yet, and the drum brakes are correct.
The casting number on the block still throws me unless the last digit is an 8 and not a 6. As far as knowing someone at the factory, i don't think that means anything. I think you had to check the box to get what options were available.
Are the pistons flat or domed? And just curious how you tell an oem gasket?
Keep in mind this truck is 42 years old. Alot can happen in that time.

[MARKDTN]

LT1 is 1970-72, not in 69. LT1 had aluminum intake, Holley 780, pop-up pistons, solid lift cam, and different heads from a truck. I don't think you have an LT1.

TH400 always has an electric kickdown.

[68350]

The block number is definetly contradicting the suffix code, but I would still feel pretty comfortable thinking its a truck 350. If it looked like it hadn't been apart or changed, then I would go with the 255 hp 350 truck engine. The LT-1 as previously mentioned would have a solid lifter cam, something like 11:1 compression, etc.

[littledeuce2]

The LT-1 was the ultimate 350 cu in (5.7 L) V8, becoming available in 1970. It used solid lifters, 11:1 compression, a high-performance camshaft, and a 780 CFM Holley four-barrel carburetor on a special aluminum intake with ramhorn exhaust manifolds and a low-restriction exhaust to produce a factory rated 370 hp (276 kW) (the NHRA rated it at 425 hp for classification purposes) and 380 lb·ft (515 N·m). Redline was 6500 rpm but power fell off significantly past 6200 rpm. The LT-1 was available on the Corvette and Camaro Z28. Power was down in 1971 to 330 hp (246 kW) and 360 lb·ft (488 N·m) with 9:1 compression, and again in 1972 (the last year of the LT-1, now rated using net, rather than gross, measurement) to 255 hp (190 kW) and 280 lb·ft (380 N·m).

Right from Wikipedia...

This engine has flat top pistons,hydraulic cam & truck heads. Alright then. Steel crank, pink rods, and I'd guess 9:1 forged pistons. I dont ever recall this being standard for the 350

[littledeuce2]

To answer the oem gasket question. It had steel shim cyl head gaskets. Which was factory at the time. Aside from that, Typically the fact gaskets were light in color and very precise in how they fit. They didnt stick out, like around the timing cover or the thermostat housing, and literally (welded on from age) cork oil pan gaskets. The rubber pan/timing cover gaskets dont appear to be anything like aftermarket. The fact that the 2nd and 3rd owners never had the engine out. The fuel pump was changed, I know that much.

Also, the block # shows it was installed in HD trucks from 68-75. My info on this is direct from the machine shop. I asked them to look it up.
The last digit is a 6 for sure.

So I think we've narrowed this down to NOT a an LT1
Lol! BTW I'm pretty sure from my video that the timing chain is original! This video was intended for the customer who isnt familiar with the internal workings of an engine.

[littledeuce2]

Then I remember coming across this on Nasty Z28. block # 3932386 for 69 its claiming LT1
http://www.nastyz28.com/sbchevy/sblock.php