Mopar 440 racers - time to legalize that shortblock!

[RocketBlock]

Just heard that NHRA tech is no longer going to look the other way on the engines built with the incorrect short-deck B block, must use correct RB raised block as dictated in the rulebook ("crossbreeding of parts prohibited"). Applies to other makes but it appears the problem is primarily with the 400 block being used for 440 applications. Also, 440 cranks are turned down significantly to fit the 400 B block mains. Compression height of the pistons will also change significantly.

[Lynn A McCarty]

So that is what they mean by "no cross breeding of parts?" What about all the other engines that are cutting 1/2, 3/4 or even 1 inch off their decks? A year ago, I called 2007 the year of the short "decks". Of course you all know that Pontiacs have a very long rod with big strokes, so Pontiacs always stroke it deeper.

Pontiac has a natural advantage of a 455 with a 10.200 deck. That allows us a piston without pin around 370 to 400 gms. You mean we might actually get one of our natural Pontiac advantages back that was given away for free?

Lynn

[Paul Precht]

Paul.

[RocketBlock]

Not only does the crank get a serious grinding just to fit the block but the intake manifold of a stock 440 won't begin to fit as it's 1" to wide. There's not enough intake manifold flange to mill away to make up that difference. It takes some serious surgery to a 6-pack aluminum intake to get it to fit a B block. By then you have a tunnel ram as the runners were more up hill. That of course is not acceptable in stock. Superstock is a lot easier to deal with.

[Chris DeGidio]

Just use the Edelbrock 383 6 pak intake.

[herbjr]

Chirs is obvious Rocket doesnt know much about these motors. The mainfolds are available out of the box, the cranks are available to drop in no need to grind as you say. The advantage is 100 grams on the piston. I know this for a fact. If you believe that 100 grams will make you run .5 quicker I have 100 acres of ocean front property near Tulsa, OK Ill be glad to sell you.

Herb McCandless Jr

They should outlaw those 1200. a set pistons rings that I know they are running

[RocketBlock]

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[RocketBlock]

Originally Posted by herbjr

Chirs is obvious Rocket doesnt know much about these motors. The mainfolds are available out of the box, the cranks are available to drop in no need to grind as you say. The advantage is 100 grams on the piston. I know this for a fact. If you believe that 100 grams will make you run .5 quicker I have 100 acres of ocean front property near Tulsa, OK Ill be glad to sell you.

Herb McCandless Jr

They should outlaw those 1200. a set pistons rings that I know they are running

Go back to class racing school. The 383 6-pack edelbrock intake does not have the correct 440 6-pack factory casting numbers. That requires at least a part number change to make it appear legal. That is direct violation ofthe rules. At least one top ten qualifier and points earner (no names) ran this engine and the intake was cut extensively and realigned to longer straighter runners for a significant horsepower increase.

The 440 factory crank never had 400 sized mains. Should you or I look upo the specs? I'll get it later.
NHRA does not allow turning the mains beyond normal bearing size replacements. Crossbreeding of parts are illegal.
440 main bearing journal size: 2.750"
400 main bearing journal size: 2.625"
Difference: .125"
Advantage: less frictional loss due to bearing speed.

The compression height is vastly changed which makes a 440 replacement piston impossible to use. So that part is illegal. It's also more than 100 grams a piston.
440 rod length: 6.768"
400 rod length: 6.358"
Difference: .410"
440 stroke: 3.750"

As you can see when using a 400 short deck block the piston pin is moved upwards. This creats a shortskirt piston which in no way could weigh 749 grams as suggested by NHRA for stock eliminator. Thats if your using the NHRA mandated length 440 rod.

Clearly, anybody that runs a 400 B block in stock has to alter the crank, pistons and intake beyond what is legal. That's a lot of work. Would you do all that for a tenth? Two tenths?

[SSDiv6]

Originally Posted by Ed OBrien

So are the ford guys that run a truck crank still ok ? Have a nice day

In Stock class, as long as you run the same OEM material and stroke as the engine you claim, using a crank in the same family is acceptable. As an example, using a cast crank within the different years of a Chevy small block, as long the stroke is identical, it is okay. However, using a forged crank in an engine that had a cast crank is not acceptable.

[Lynn A McCarty]

Originally Posted by Chris DeGidio

Just use the Edelbrock 383 6 pak intake.

Sounds like "Cross Breeding" to me! Specifically stated in the rule book for Super Stock and Stock.

Lynn