[Fastest65]

Gentlemen,
I need help on this one please. I have a line on a
casting #12556110, 4 bolt, GEN VII, 496 Vortec Truck
engine complete.
I have looked on Mortec for castings and doesn't say too
much other that what I've stated already. It is a C.O.P. setup
I was wondering if it is tall deck or short deck? and could a guy
swap out heads and intake and run a HEI? Could this be a good torque monster? OR is
it better left alone?
Thank you

[cope]

im not sure about the head and intake swap but my boss has one in his 2000 HD chevy and its got some serious balls even hauling 2000lbs around everywhere.

i do know that they burn a quart or two of oil inbetween changes because they have quite abit of piston slap. last i looked my boss had 140000 on his and still running strong probley close to 200000 now.

[Fastest65]

Thanks GM cope,
I am not sure how to find out more either. Tall deck/Short deck?
Swapping out intake/heads etc.. Whether they will accept regular
water pumps, alt brackets etc...
Does anyone else know about these engines?
tHanks

[Double_v23]

I am pretty sure they are their own animal. Where you can swap some parts between Gen IV, V, and VI, there is nothing that will interchange with 8.1 litre.

Your only option for carbeuration would be to find a company that makes an intake for the swap, but these vehicles don't even have provisions for a distributor so doing the old "swapping a carb and hei onto a EFI motor" will not work for the 8.1

If you want to hotrod that motor be prepared to spend 10,000 plus (that is IF you have the stock electronics)

[Fastest65]

Double V23,
Thanks for the heads up. That is kind of what I was thinking.
This 496 add has been posted for along time...now I know why.
Guess I'll stick with my .030", 4-bolt 454 that I don't know what
to do with. It is just sitting bolted in the engine bay with no heads.
Stuck because I don't know which way to go. All I have is .030" flat
top pistons that are .040" in the whole. I have 063's shaved .060" to
get the CR up there or I have a set of 049's. Do not want to changes out pistons for a small dome (no $$). So I was thinking fresh heads and a nice
cam. If I throw the 049's on my CR will be 8.5 at BEST probably less so I
cannot put any good cam in her.
Thought?

[Double_v23]

Yeah, get a stroker crank and some new pistons and make your own 489 stroker. It is easier than you think. Deck the block to .010.

Get yourself some 9:1 pistons and that thing will rip.

Usually 9:1 would be one valve relief flat top piston with a .038 gasket, .030 over with the piston .010 in the hole. But that is with a 118cc chamber so it will be more with a closed chamber head, just verify your chambr volume and purchase the appropriate piston.

The rods can be reused but you can get a new set of H-beam 4340 forged rods for around 400 bucks if you shop around and this is important if you want to push it.

Don't believe the small block guys about needing all kinds of compression to run a big cam...it is different for BBC's. Look at Big Block Shawn he makes 700-800 HP on pump gas. My 496 is 9:1 and is absolutely crazy, I am running a 284-296 Adv duration (254 dur @.050) .660 lift roller cam and it idles nice and you won't believe the power it makes. I actually wish I would have gone bigger.

What were you going to spend on that GEN VII? You could stick that into the motor you have and make something really nasty.

[Fastest65]

Thanks again V23
Could you be more specific please? If I find a different
crank (which one) and if I used the same rods the only
difference with be the rist pin height on the piston?
Expand please. I am ignorant with stroking and what to
guy.
Thanks.

[BOBCRMAN@aol.com]

The new generation 496 is an animal all itself. A tall deck. 4.250 bore, high pin hole f/t pistons, 4 3/8 stroke and extra long 7/16 rods. "0" balance balancer/pulley. Weighted flywheel.

Not too bad right?.

The heads have unique, equally spaced, tall narrow intake ports. Raised small "D" port exhausts. 2.19 intake valves and large exhaust valves. (at least on the one in front of me.)

Now, the bad!

The head bolt hole number and pattern is not the same as previous BBC's. Also no way to adapt early heads to block.

[Double_v23]

Originally Posted by Fastest65

Thanks again V23
Could you be more specific please? If I find a different
crank (which one) and if I used the same rods the only
difference with be the rist pin height on the piston?
Expand please. I am ignorant with stroking and what to
guy.
Thanks.

You are right, all you would have to do is get a stroker crank, (4.250 inches) then you would use your stock 6.135" rods. Then you would get new pistons with the appropriate compression height. (x inches) so the formula goes like this

1/2 stroke (2.125) + rod length (6.135) + compression height (1.540) = deck height (9.8).

If you decide to assemble your own parts then you have to make sure you get a set of pistons with short skirts so that the piston does not hit the crank on the down stroke. You can eliminate this problem by going with a 6.385 (+.250) rod and a 1.290 compression height piston.

If you are running a tall deck (10.2) I would recommend compensating the extra distance by getting a set of rods that are 6.535. (which is what I did on mine).

Stock BBC's can take alot of abuse, I have read several books that say that 2 bolt mains and cast steel cranks can take up to 600 horsepower and 6500 RPM. So by that standard there are several kits available with cast steel cranks that are very affordable. And most come with balancing as an option. I would go for the internal balance crank so that you can use any internally balanced flywheel or dampner. This leaves your options open.

I would check out www.competitionproducts.com they seem to be the most affordable with the best reputation and they have kits that range from mild performance to all out racing. I would definately recommend calling them as well, they have a lot of deals that aren't advertised on their website.