Need help identify my BB

[Bigrod1984]

Also if anyone wants to chime in on the sleeper on this truck would help too. What gets me is how well the construction is on it, ie how it's mounted to the frame and to the cab. Also what's really interesting is the truck and sleeper (notice there the same color) appears to have the original paint no signs of repaint. Pics of truck in intro forum.

 

[pduffyd]

BigRod
Hey at least there is one mystery solved, its a 454 MKiv LE8. So that explains the 454 head codes. But the block casting number doesnt match. Replaced?

Right so my book says that an LE8 is a 86-89 454 with 240 net HP, low deck truck engine only with 2 or 4 bolt mains, small oval port (peanut) cast iron heads, cast iron crank, hyd cam, cast intake and Q jet carb. Well this was the ORIGINAL engine.

I was looking at this same book for cylinder heads and block number this time, Instead of the cheat sheet.
Your Heads were there 3964290, this book says 69-76, large oval port, closed chamber, 2.06 in/1.72ex valves, for 396,402,454.
The Block number 3999290 says its a 396ci, 68-69, 2 or 4 bolt mains, Truck engine. That kinda matches your heads?

Now I have found this info here.
https://www.enginelabs.com/news/reference-chevy-engine-block-casting-numbers/

You must be registered for see images attach

Heads still match the info above. So replacement engine?

 

[Bigrod1984]

BigRod
Hey at least there is one mystery solved, its a 454 MKiv LE8. So that explains the 454 head codes. But the block casting number doesnt match. Replaced?

Right so my book says that an LE8 is a 86-89 454 with 240 net HP, low deck truck engine only with 2 or 4 bolt mains, small oval port (peanut) cast iron heads, cast iron crank, hyd cam, cast intake and Q jet carb. Well this was the ORIGINAL engine.

I was looking at this same book for cylinder heads and block number this time, Instead of the cheat sheet.
Your Heads were there 3964290, this book says 69-76, large oval port, closed chamber, 2.06 in/1.72ex valves, for 396,402,454.
The Block number 3999290 says its a 396ci, 68-69, 2 or 4 bolt mains, Truck engine. That kinda matches your heads?

Now I have found this info here.
https://www.enginelabs.com/news/reference-chevy-engine-block-casting-numbers/

You must be registered for see images attach

Heads still match the info above. So replacement engine?

Thank you pduffyd for all your research on this your awesome.I agree the engine very well could have been replaced at one time or another. I do have some interesting info on it though. My great uncle worked for GM from 73-92 and has past since but while talking to his son about the truck a couple days ago he mentioned some things to consider. He almost 100 percent believes that engine is the original even with those numbers. According to him there was a large warehouse that GM stored a lot of NOS engine parts for many years and instead of producing new blocks for sertian types of vehicles they simply pulled one from the warehouse and stamped it after assembly. Hince a different font for the casting # to the serial and would also lend possible truth to why a block # for a 1972 Chevelle 402 engine is the same number used in a 1982 C30 with an incomplete chassis. Which would also make sense to the heads of the same era. He also said that most over produced engines and parts were originally produced for vehicles that never met the sales criteria. Other words parts were produced for vehicles that weren't even made. So they stored them and used the back stock later on, for what reason who knows shortage in engines, transmission ect. IDK he may be full of sh**. Thanks to all awesome peeps on here for looking at all my headache. Rock on

 

[pduffyd]

Yeah the 70-72 402ci truck engine sounds like a match to me, with those heads in the same years.

Doesnt seem to be an LE8, I have one, I put in my C20, it has a casting number 14015445 Big Block V8 1978-1990 454, 2 bolt or 4 bolt mains. I lucked in on a 4 bolt!

Good Luck.

 

[Bigrod1984]

Yeah the 70-72 402ci truck engine sounds like a match to me, with those heads in the same years.

Doesnt seem to be an LE8, I have one, I put in my C20, it has a casting number 14015445 Big Block V8 1978-1990 454, 2 bolt or 4 bolt mains. I lucked in on a 4 bolt!

Good Luck.

Again thanks pduffyd for everything, I think we're both lucky to have a early BB. Seems there getting quite rare around here, or at least ones that haven't been machined to death. Or not capable of even running. Good luck and Rock On brother!

 

[pduffyd]

If you are ever looking at getting a 454 LE8, have a look for a motorhome thats being wrecked. Thats where I got my 30000 mile BB, all original for no money really. Good compression and bores.
If you use your heads they will flow better than the peanut ports on the LE8 for sure. I want low down torque for towing, so I kept the peanut heads. Ive just replaced the valve springs with compcam 911-16 springs for a better RV cam and using a proflo4 EFI later, once everything else is done on my build. SM465 behind that with 3.21 14BB FF rear.
Anyway, yep always fun playing with the rat engine!

 

[Bigrod1984]

If you are ever looking at getting a 454 LE8, have a look for a motorhome thats being wrecked. Thats where I got my 30000 mile BB, all original for no money really. Good compression and bores.
If you use your heads they will flow better than the peanut ports on the LE8 for sure. I want low down torque for towing, so I kept the peanut heads. Ive just replaced the valve springs with compcam 911-16 springs for a better RV cam and using a proflo4 EFI later, once everything else is done on my build. SM465 behind that with 3.21 14BB FF rear.
Anyway, yep always fun playing with the rat engine!

Yes sir and unfortunately what I know now didn't help for what I should have known then. I used to scrap metal for a living in early 2000s and I cant tell you how many 10-50k BBC, BBF and BBM we scraped and over half of them were running fine. I think the one I kick myself over is the 83 model 25' beaver class c that had a Mopar 426 himi from the 70s in it and it would boil the the tires off that dually motorhome in all 3 gears. Of course I scraped it because I needed the money and I was stupid. Anyway I have plenty of mice running around here but only 1 rat. Rock On!