Yes Crazyhorse it will be internally balanced
I found a Callies 4.25 stroke crank made for the one piece seal.I did not think that you could remove enough weight from a 454 ext. balanced flywheel.

Rob

[ 01-07-2002: Message edited by: rws ]

[ 01-07-2002: Message edited by: rws ]

I think that Summit sells them also.

Jon

You add mallory metal instead of removing material from the flywheel.

Who knows if the gen 5 heads will bolt to a mark 4? I have an opprtunity to buy many pairs of new assembled gen 5 rec port heads. Dan

I know you can't use gen IV heads on a Gen V block, although I believe there is a special head gasket can be used to make it work.

The cooling passages on the GenIV's are round while on Gen V and VI they are a trapezoid shape. The GEN VI cooling passages are modified to accomodate Gen IV heads.

So with all that in mind, if you got the gasket that lets you adapt the the Gen IV head to a Gen V block, you could probably make it work provided the gasket does'nt cover the cooling passage on the Gen IV block.

I believe the gasket is made by the Dana corporation.

A lot of the gen5 & 6 use non adj valve train and will need to have machine work done to make them suitable.

The non-adjustability of the Gen 5 heads is not really an issue unless your spring pressures are very high. I was able to get screw-in studs that replace the shoulder bolt and allow the use of.Mk 4 adjustable valvetrain pieces. I think they came from ARP but should also be avaliable from a variety of manufacturers. I believe Merc uses a set up like this on Gen 5 HP 500s. One other thing that nobody has mentioned is that at least with the Gen 5 there is no provision for a mechanical feul pump so electric pumps will be needed.

[ 01-09-2002: Message edited by: B.R.S. ]

If you are running engine plate mounts on your Gen 4 engine and you swap over to gen 5 or 6. You will have to purchase new plate mounts. The Gen 4 mounts will not fit they do not clear the oil pan.

The Gen V carbed engines use a seawater pump-mounted mechanical fuel pump. Also, I've swapped Gen V and Mark IV engines using the same plate mounts without any problems.

[ 01-09-2002: Message edited by: Crazyhorse ]

Crazyhorse, You are right in one instance if you are swapping from Gen 5 to Gen 6 the plate mounts are the same. But if you are trying to mount a gen 4 plate mount on a gen 5 or 6 it won't work.