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Discussion Starter · #1 ·
I sent my '04 Heads to SBC from North Carolina for scottsmans and I just found out that SE FlatTops won't work with their oversize valves! I must have missed this cause I dont remember reading this anywhere. I didn't plan on having to replace the pistons too. My 95"/TW37G build has 20K miles on it.

Questions:
Can I cut the piston reliefs myself with a dremel and not totally screw it up?

Is it harder to replace pistons then install Gear Cams? I've done that. Any special Tools needed?

Is just getting the ports tooled, milling the heads to get 9.8:1 CR and keeping "stock valves" worth it? Any power gain form this?


Talk about disappointed....
 

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You need to have a machine shop " flycut" your pistons. Then I would ball hone your cylinders and install new rings on your pistons. Or you can use Wiseco pistons ,they have big pockets in them.
 

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Regarding the degree of difficulty in replacing pistons, I'd say it's probably easier than installing cams. You don't need any special tools; you can cut a piece of plywood to set the piston on in order to keep it level when you slide the cylinder over it. A flat blade screwdriver is a good substitute for the other tools the manual mentions. Otherwise, just follow the manual or the manufacturer's instructions and make sure you get the rings in the right place and the gaps offset. Other than that, there's really no wrong way to do it.

Ragnar
 

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I sent my pistons and my heads to Dan Baisely he fitted the pistons and fly cut my SE flat tops.I would call SBC and ask if they would fly cut the pistons for you. Put some rubber hoses on the cylinder bolts after you remove the cylinders to protect the pistons and rings.
 

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You can do the work with a dremel on the bike but a die grinder would be much faster. Check this site for how much to remove.
http://www.harleyhog.co.uk/1550/bb9online.htm
Just tape it off real well, i.e. seal the piston to the top of the barrel with masking tape and get grinding. Use shop vac to suck up metal shavings then air compressor to blow it off real well. Be careful and keep it clean....................Ward
 

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Discussion Starter · #6 ·
Thanks

Thanks for the replies. I talked with SBC and they have an oversize jims 1.9000 (vs 1.9400) Intake they will use that can be used with stock cast SE Flattops. 40 thousandths smaller then the other valve. I believe I can live with that.

Ward - That HarleyHog site is a killer site. Used it to help install my Gear Cams.
 

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It would still be prudent to clay your piston clearances. Just put some modeling clay where the valve reliefs are and put on the heads and turn it over by hand. Never hurts to be too careful in this case...........Ward
 

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SBC will flycut your pistons for I think about $40. Also unless things have changed when dealing with those guys make sure they are working on YOUR heads, and not just doing an exchange job. I sent them pristene '03 heads and got back mix&match nicely ported doorstops.
 
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