8.1 and 502's

[folkenheath]

Both the 496 and the 502 are called an 8.1 liter.

That's not true, the Gen VI 502s have 8.2L cast right into the block.

Someone will correct me if I'm wrong, the 496's in late model trucks is an LS based engine where as the 502's are a classic BB design.

This appears to be true if you look at the top of the engine and see the coil on plug ignition and the funny intake, but that is where the similarities end. The block is based on the tall deck big block, but with some changes. It has provisions for the crank sensor in the rear, factory oil cooler ports, the head bolt pattern is different for some of the bolts, (many are the same location), dual motor mounts, etc. But it is far from an LS engine, not even close.

 

[swedester]

my -02 496.
I guess people call them ls because the intake and head design,true cathedral ports,almost 4" tall,this one is going in my 62 impala project.

 

[Stomis]

You guys are correct the 8.1L is a revised big block with an LS inspired head/intake combo. Dont confuse that with it actually being an LS series engine like the 6.0, 5.3, or 4.8 because its not.

We have both an 02 3500 with the 8.1L and an 08 with the 427 Truck LS engine and my boss says the 02 with 150,000 miles more tow 1000x better.

 

[Greg72]

the Gen VI 502s have 8.2L cast right into the block.....

W3RD.

 

[greatwhitez71]

do want an 8.1

gonna drop that infront of my nv4500 in my brown truck

 

[imiceman44]

W3RD.

Now I am surprised, didn't Scott work on that engine?
And he said they are all 8.1 he's starting to get senile.

 

[4X4HIGH]

Now I am surprised, didn't Scott work on that engine?
And he said they are all 8.1 he's starting to get senile.

Yes I did work on that engine, give me a break though i'm not getting senile that was about 3 years ago, I can't help it if Greg takes FOREVER to get his project done.

 

[Stomis]

Ya know I've been thinking on big blocks vs small blocks lately and I cant figure out (other than weight) why people even bother with small blocks. I mean in a truck a small block is generally taxed enough to really move the vehicle that you wind up with 15mpg on a good day.

Now compare that to say the 13mpg on a good day that guys pull from a 454 or 496 and it really makes me wonder why bother?

The same carries over to cars. I've been doing reading on report of big block g bodies pulling 10-12mpg in town no problem. A hot small block is probably gonna do the same so what the point?

 

[thatK30guy]

do want an 8.1

I want both 8.1 and 8.2 just for bragging rights.

 

[imiceman44]

Ya know I've been thinking on big blocks vs small blocks lately and I cant figure out (other than weight) why people even bother with small blocks. I mean in a truck a small block is generally taxed enough to really move the vehicle that you wind up with 15mpg on a good day.

Now compare that to say the 13mpg on a good day that guys pull from a 454 or 496 and it really makes me wonder why bother?

The same carries over to cars. I've been doing reading on report of big block g bodies pulling 10-12mpg in town no problem. A hot small block is probably gonna do the same so what the point?

Actually I think the other way around:
Why bother with big blocks when you can make the same size and power from a small block and much cheaper.
It's too much to build a BB, cheaper to build a SB.
Now if you go on stock engines then your argument can hold water.
I do however prefer the V8 and V6 engines versus the 4 bangers because the fuel economy difference isn't there to justify going that small and the power is there when you need it with the bigger engines.
I am getting 21-22mpg with my 97 vortec 5.7 in my 2wd van all stock.
Why would I use a similar vintage truck with a 2.0 that gets me 21-22 (my beighbors 98 nissan 4 banger)

 

[Stomis]

Actually I think the other way around:
Why bother with big blocks when you can make the same size and power from a small block and much cheaper.
It's too much to build a BB, cheaper to build a SB.
Now if you go on stock engines then your argument can hold water.
I do however prefer the V8 and V6 engines versus the 4 bangers because the fuel economy difference isn't there to justify going that small and the power is there when you need it with the bigger engines.
I am getting 21-22mpg with my 97 vortec 5.7 in my 2wd van all stock.
Why would I use a similar vintage truck with a 2.0 that gets me 21-22 (my beighbors 98 nissan 4 banger)

Sure you can make big power on a small block but the all in at 1500rpm curve of a big block will never be there with a small block. There more to it than just peak numbers.

Plus remember RPM range, the need for huge stall, bad vacuum.

 

[blazin_blazer]

whats the deal w/those heads? as i understand, there was some kind of change & they won't fit early bbc & from the looks of it a reg ol bbc intake won't fit either. what about a reg ole hei dizzy? is there any good sites or threads about those differences? i'm new to bbc stuff & would like to learn more so i don't buy stuff i can't use.

 

[Stomis]

whats the deal w/those heads? as i understand, there was some kind of change & they won't fit early bbc & from the looks of it a reg ol bbc intake won't fit either. what about a reg ole hei dizzy? is there any good sites or threads about those differences? i'm new to bbc stuff & would like to learn more so i don't buy stuff i can't use.

The heads and intake are cathedral port, modeled after LS1 and LS4 design. Its basically oversized LS stuff bolted on a traditional big block bottom end. Except the bottom end is changed just enough that it wouldnt work on say a 454.

 

[blazin_blazer]

can you get a carb intake &/or hei dizzy for that 8100 bbc?