Hot rods big bear cylinder idea

[YamahaNutz]

Did a decent amount of searching, but have questions on an idea.

Have an 07 Raptor 350.

Plan to use the hot rod stroker crankshaft
Big bear 400 cylinder jug
12:1 piston(yfm350)

I have found through search results using this combo uncut leaves the piston around 1-2mm under where it should be. I'm thinking I could leave the base gasket out, measure piston depth, calculate, and either order thinner head gaskets and/or only mill the jug a little.

I'm aiming for 10.25-11:1 compression.

Would this combo work in theory? I could use a JE piston, or a Wiseco with a factory pin, and have a easily available piston. And at what point is the squish too big in these engines?

 

[beastlywarrior228]

You'll need more than thinner gaskets. If you can find the 7 mil crank you can use the oem big bear rod.

 

[YamahaNutz]

Already looked for the 7mm crank. Last one I saw was over a year ago on ebay and they wanted double price for it.

I'm curious if either the stock or big bear timing chain would work if I milled the jug down 1-1.5mm(I'm guessing here). One is 90 and the other is 92 links.

 

[ag2560]

I did this setup on my most recent motor. If you get a 4mm stroker crank and put a big bear 400 rod on it with a 400 cylinder you`ll need to take around .050" off of it. Then you can use a custom base gasket from cometic to set the deck height where you want it. You`ll also need the big bear timing chain, slider and an adjustable cam gear to get the cam timing right. You may have to put a manual chain adjuster on it too because the stock one will almost be fully extended with this setup.

 

[YamahaNutz]

I'm wondering if I can pop the sleeve out and just mill the cylinder down. Stock rod/hot rods stroker rod is 112.5mm and big bear 400 is 117mm center-to-center. Sounds like it will probably be around .125" cut. The timing chain would be the obstacle. I could have a stronger rod. I've read mixed things about the factory big bear rod.

I'll talk to my machinist buddy about if it's feasible to do. Or, I could just shell out the money on a custom rod.

I can also see if hot rods will sell me a crank un-pressed to help cost of putting in another rod. Waiving any warranty, of course.

I'll probably pick up a used 400 cylinder cheap so I can see if this amount of material can be taken out or not.

I'm playing with ideas, but do plan to do some sort of bastard stroker.