BBC HEADS # 10101140 Does anyone know more than mortec about them?

[74_schiada_flat]

i just got a 427 talldeck cast # 10114184
with a set of heads cast # 10101140
Mortec doesnt tell me anything on the heads other than oval port closed chamber.
I know this is a good block but are the heads any good?
also somebody told me that there was a way to stroke it with longer rods and turn it into a 511. is that true?
if so how?

[GofastRacer]

Well if you're going to build a big motor to make a bunch of power those heads are not going to cut it, they're good heads for the street though!... The block is from pre 454 days so it won't accept a 454 crank as is so you will have to do some clearancing on the bottom of the cylinders and you can put a .250 stroke in it and bore it .060 and make a 496, to make a 511 you need to go .125 over, even though those old blocks are thick walled, I would still get it sonic checked for core shift!....

[Fiat48]

That block number comes up Gen V...which I am not familiar with. Gen IV is all I know.
Does that block have a one piece rear seal or 2 piece?

[74_schiada_flat]

Well if you're going to build a big motor to make a bunch of power those heads are not going to cut it, they're good heads for the street though!... The block is from pre 454 days so it won't accept a 454 crank as is so you will have to do some clearancing on the bottom of the cylinders and you can put a .250 stroke in it and bore it .060 and make a 496, to make a 511 you need to go .125 over, even though those old blocks are thick walled, I would still get it sonic checked for core shift!....
i have some 291 heads that i was going to sell to recoupe some of the cash i spent on the motor.
should i keep them?

[GofastRacer]

Wow just looked up the numbers, something don't make sense, it says 427 but it says 91-92 they quit making 427's a long time ago!..

[74_schiada_flat]

Wow just looked up the numbers, something don't make sense, it says 427 but it says 91-92 they quit making 427's a long time ago!..
so what do you think?

[GofastRacer]

i have some 291 heads that i was going to sell to recoupe some of the cash i spent on the motor.
should i keep them?
I would sell them, not worth putting money into them, they would be good for a tow vehicle though!..

[GofastRacer]

so what do you think?
Get it magged and sonic checked and go from there!..

[Fiat48]

There was a remake of the 427 tall deck that were thin wall castings. I know how to identify if it is a Mark IV. Check that rear main seal.

[GofastRacer]

There was a remake of the 427 tall deck that were thin wall castings. I know how to identify if it is a Mark IV. Check that rear main seal.
Hmmm, guess I missed something I thought they brought it back out as a Bowtie block!..