RickR

I have a good Gen V 454 (9.1, adjustable valve train, head work including bronze valve guides, Tefelon seals and Valve job per Dennis Moore's recommendations in his BBC Marine Book) but want more cubic inches and roller hyd cam. I already have Gils and MSD.

What extra parts would I need?

502 Block
Crank

( Mark IV and Gen V 454 and 502 cranks are the same but the Gen VI 454 and 502 are different?)

Pistons
Rings
Damper (or current Gen V and an advance timing light)
Cam
Lifters
Pushrods
Timing Cover

THANKS!

Scarab28

The Mark !V 454 crankshafts are not the same as a Gen V 454 crankshaft. Mark !V's use the 2 piece rear main where as the Gen V's use the single piece rear main.

Gen V and Gen VI 454 and 502 cranks are the same.

TomR

Scarab28 is correct, GenV & GenVI are the same crank. Also, do your self a favor & spend the money for a "FluidDamper" harmonic balancer. They are already degreed so you can use a conventional timing light. They will also help your motor's performance & longevity!
Make sure when you order your cam that you order a cam specific for a GenVI. The front of the cam is machined for a cam retainer plate which is a great design, eliminates the need for a cam button. You will need a GenVI timing chain & gears as well.

I have also been around the block on this roller lifter issue, weather or not to use the GM lifter set up or go aftermarket link bar design. After trying both types, no diff in performance, the GM design is better! I talked to both people from GM and tech people from CompCams and they told me it was fine to run the GM roller lifters with .625 lift (gross). I also double checked clearances after install and there is plenty.

Dennis Moore

The steel cankshafts built for the one piece rear main seal Gen V and Gen VI look the same but are not interchangeable, the 454 crank is balanced different than the 502.
The cast iron 454 crankshaft is balanced different than the steel 454 and uses a different flywheel (only on the Gen V and VI).
Sincerely
Dennis Moore

TomR

Dennis,
Thank you for pointing that out. I remember reading about the 454 & 502 being balanced different in your book.
RickR, the book that Dennis wrote "BigBlock Chevy Marine Performance" listed all of the part #s for cranks and flywheels and what can be used with what.
No matter if you are doing this project yourself or having someone do it for you, you really should get a copy of this book. You will find it very informative!!

415stinger

I also heard that the distributer drive gear needs to be replaced with a hardened drive gear when making this swap. Anybody else know about this?

TomR

It depends on the cam you run. GM high performance cams require a "melonized" dist gear, most Comp cams don't, it depends on what the distributor drive gear is made of on the cam.

rws

iTrader: (3)

You will want to find a Gen 6 502 Block casting # 10237300 If I was going to spend the Money for new pistons ,crank I would spend a few more dollars and build a 540cu. 4.250 stroke 6.385 long rods and off the shelf pistons are available.Several guys on OSO are running 540's . To spend the money and time to increase you cubic inches by only 48 will not be that big of a difference verses upping the cu by 86.You could sell your complete 454 short block to help offset the cost a new set of Rods and a better crank than a stocker. Check out this thread it may be helpful.


http://www.offshoreonly.com/forums/s...threadid=40470

Rob

RickR

Will a Gen V 502 crank (#14097044 same for 454) work in a Gen VI 502 with some JE pistons?

TomR and Dennis
I'm using BBC Marine Performance book as a guide. Info was very helpfull for my 454

rws
Thanks for the link but I think the 502 will be plenty for my 22 Classic Donzi

Dennis Moore

The GM assembled 502 uses JE pistons. The JE pistons that are used by GM have metric rings. Purchasing aftermarket pistons from JE gives you the same piston but with standard rings. You are going to have the assembly balanced aren't you? Should be a nice engine when you are through.
Dennis Moore