700 cylinders on a 2004 600 engine

[donbrown]

Just want to start this discussion real basic to see the pro's and con's of taking a 2004 RMK 600 engine and replace the cylinders with 700 cylinders.

What needs to be done in detail?

Different pipe/can.

Rejet the carb to?

anything else?

 

[600xc4me]

Im no expert but i dont think it will wor. The 600 is a small block and the 700 Is a big block engine.

 

[donbrown]

Im no expert but i dont think it will wor. The 600 is a small block and the 700 Is a big block engine.

People have done it.

People on here have said they bolt right on while others say it takes just a tad bid of engineering.

Are you saying they overbore the existing 600 cylinders to fit a 700 piston?

 

[600xc4me]

People have done it.

People on here have said they bolt right on while others say it takes just a tad bid of engineering.

Are you saying they overbore the existing 600 cylinders to fit a 700 piston?

o ok, I know I have heard of people swapping newer VES 700 cylinders on to the older big block 600 cases. But never heard of anyone doing that with the motors your talking about. I thought the big block and small block engines had completely different cases? I know the motor mount, mounting is very different. I swapped a complete big block 700 VES into an 01 600 XCSP which came stock with the early small block 600 VES. And the mounting was about two inches off if I remember correctly. Didn't compare the cylinder to case mounting though. But thought it was also quite off? Maybe I'm wrong.

 

[sled_guy]

Can't put 700 bigblock cylinders on the 600 small block.

That's why there is such a thing as a 660. 600 cylinders punched out to fit the 700 pistons and ported accordingly.

sled_guy

 

[600xc4me]

Can't put 700 bigblock cylinders on the 600 small block.

That's why there is such a thing as a 660. 600 cylinders punched out to fit the 700 pistons and ported accordingly.

sled_guy

Ok sweet. That's what I was thinking.

 

[donbrown]

Can't put 700 bigblock cylinders on the 600 small block.

That's why there is such a thing as a 660. 600 cylinders punched out to fit the 700 pistons and ported accordingly.

sled_guy

Sop you get some 600 scared cylinders and bore them out and replate / port them to fit a 700 stock piston and you got a 660/685?

Gotta change the exhaust and carb needles.

 

[sled_guy]

700 big block pistons on a 600 small block crank yields a 660. You don't have to mod the cases, but if you have the motor apart I suggest you machine the casting right below the pistons for extra clearance.

For the 685 it uses a different piston, a Wiseco I believe. I don't know if it is a stock piston for any particular motor or if its custom made. It for sure requires bottomend machine for the piston skirt to clear.

On my 660, if you didn't bore the carbs, the needled didn't need to be changed. Head has to be cut to fit the bigger pistons as well.

sled_guy

 

[donbrown]

700 big block pistons on a 600 small block crank yields a 660. You don't have to mod the cases, but if you have the motor apart I suggest you machine the casting right below the pistons for extra clearance.

For the 685 it uses a different piston, a Wiseco I believe. I don't know if it is a stock piston for any particular motor or if its custom made. It for sure requires bottomend machine for the piston skirt to clear.

On my 660, if you didn't bore the carbs, the needled didn't need to be changed. Head has to be cut to fit the bigger pistons as well.

sled_guy

What year is your engine?

I understand exactly what you are saying. I understand this is what Carl's cycle does for its 660 kit.

People on here PM'd me and declared they have swapped out cylinders from various years without any "machining" of the crankcase ,cylinders and heads for clearance, squish etc. mods

 

[sled_guy]

Mine is an '04 600 motor. I've worked on over a dozen different 660/685s from all years starting in '01 and up.

There is a casting in the crank case on the front side of the motor that a 700 piston will drag on. With the 660 you can hold the cylinders back to the intake side when installing and it will clear that casting... barely. That's why the Carl's 660 kit is a bolt on.

685 however is a little bigger piston and won't clear that casting.

SLP machined that casting even on their 660 to add a little more clearance. If I have a 660 bottomend apart I have that casting machined as well just to ensure proper clearance.

As for cylinder swapping... you can not swap a big block cylinder on to a small block bottomend. The cases are completely different, water passages and water pump are different and the crank rod spacing is about 1/2" narrower on a small block than a big block. It will not work no matter what you try.

However, the newer 700 and 800 are quote "built off the small block" bottomend. Those cylinders, depending on what year after '07, will interchange. The 700 for sure, the 800 if you are talking about the '09 600 race motor.

sled_guy

 

[donbrown]

Mine is an '04 600 motor. I've worked on over a dozen different 660/685s from all years starting in '01 and up.

There is a casting in the crank case on the front side of the motor that a 700 piston will drag on. With the 660 you can hold the cylinders back to the intake side when installing and it will clear that casting... barely. That's why the Carl's 660 kit is a bolt on.

685 however is a little bigger piston and won't clear that casting.

SLP machined that casting even on their 660 to add a little more clearance. If I have a 660 bottomend apart I have that casting machined as well just to ensure proper clearance.

As for cylinder swapping... you can not swap a big block cylinder on to a small block bottomend. The cases are completely different, water passages and water pump are different and the crank rod spacing is about 1/2" narrower on a small block than a big block. It will not work no matter what you try.

However, the newer 700 and 800 are quote "built off the small block" bottomend. Those cylinders, depending on what year after '07, will interchange. The 700 for sure, the 800 if you are talking about the '09 600 race motor.

sled_guy

Thank you for the information.

So with my 600 ... I can get the cylinmders bored for a 700 piston and have it ported and I am good?

How much would it cost .... $400 plus the pistons?

 

[sled_guy]

Carl's is $1395 exchange for the motor work. That includes cylinders/gaskets/head/pistons/valve mods. On mine I also put on a single pipe, vforce reeds and bored the carbs.

I will say that it's not as easy as just boring them out to fit the 700 piston. The porting is a big part of it.

sled_guy

 

[donbrown]

Carl's is $1395 exchange for the motor work. That includes cylinders/gaskets/head/pistons/valve mods. On mine I also put on a single pipe, vforce reeds and bored the carbs.

I will say that it's not as easy as just boring them out to fit the 700 piston. The porting is a big part of it.

sled_guy

It stands to reason a proper port job to make the cylinders correct.

Carl's exchange wants a set of good working cylinders as part of the deal.

 

[donbrown]

Mine is an '04 600 motor. I've worked on over a dozen different 660/685s from all years starting in '01 and up.

There is a casting in the crank case on the front side of the motor that a 700 piston will drag on. With the 660 you can hold the cylinders back to the intake side when installing and it will clear that casting... barely. That's why the Carl's 660 kit is a bolt on.

685 however is a little bigger piston and won't clear that casting.

SLP machined that casting even on their 660 to add a little more clearance. If I have a 660 bottomend apart I have that casting machined as well just to ensure proper clearance.

As for cylinder swapping... you can not swap a big block cylinder on to a small block bottomend. The cases are completely different, water passages and water pump are different and the crank rod spacing is about 1/2" narrower on a small block than a big block. It will not work no matter what you try.

However, the newer 700 and 800 are quote "built off the small block" bottomend. Those cylinders, depending on what year after '07, will interchange. The 700 for sure, the 800 if you are talking about the '09 600 race motor.

sled_guy

What year / part number cylinders will work on a 2004 RMK 600?

3021333 and 3021257 ?

 

[sled_guy]

I don't know... the expense of new cylinders hasn't made sense to me. Having Carl's bore/port/re-nik and send me all the pieces needed was the route I've always taken.

sled_guy

 

[donbrown]

I don't know... the expense of new cylinders hasn't made sense to me. Having Carl's bore/port/re-nik and send me all the pieces needed was the route I've always taken.

sled_guy

I can get a set of used cylinders needing a bore/port/re-nik for a few dollars.

Where I live there are motorcycle "race" factories everywhere and to get a cylinder bored ported and re-nik with a dialed in magna flow will be an avenue I would like to look at.

What kind of needles do you use at 8000 feet?

 

[sled_guy]

3021333 is the stock cylinder on the '03 and newer motor. The other one is the old style with the old style exhaust valve assembly. Both will work, just depends on what valve assembly you have.

I'll have to dig through my notes at home to find the needle number. If you don't bore the carbs you just run the stock needle.

Again this is on a Carl's 660 with their single pipe.

sled_guy

 

[donbrown]

3021333 is the stock cylinder on the '03 and newer motor. The other one is the old style with the old style exhaust valve assembly. Both will work, just depends on what valve assembly you have.

I'll have to dig through my notes at home to find the needle number. If you don't bore the carbs you just run the stock needle.

Again this is on a Carl's 660 with their single pipe.

sled_guy

The sled is setup by Carl's on a 600 motor.
Recarbed / clutch kit and Carl's pipe which is also for the 660.