Anyone build a Fatso lately?
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Grand HDF Member
Joined: Nov 2009
Posts: 4,315
Likes: 1,663
From: Tampa
Anyone build a Fatso lately?
Just wondering. They look like more of a pain in *** than worth it considering the pushrod angle mods and special connecting rods you'd need to source, but there's TONS of used TC top ends out there to make it appealing, especially if you needed a few more cubes over a stock Evo and wanted a cleaned up motor in the process.
Tourer
Joined: Apr 2007
Posts: 412
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From:
You don’t need special connecting rods. You need to weld & relocate the intake pushrod holes.
I lent somebody my fixture to do it some years back. I have the tool for cutting the heads that I think was originally a Merch tool but Jim’s sells it now. I did mine with Sputhe cases.
I lent somebody my fixture to do it some years back. I have the tool for cutting the heads that I think was originally a Merch tool but Jim’s sells it now. I did mine with Sputhe cases.
Tourer
Joined: Apr 2007
Posts: 412
Likes: 281
From:
Sputhe had pistons for them. I don't know if they still do. When I did mine he also had fat O-rings where you flipped the intake pushrod tubes upside down. You could get away without welding if you wanted to.
Delkron was offering the pushrod relocation service but I think they're out of business. I thought they had a Wiseco piston for that setup too but don't quote me on that. It's been a while.
Jim's used to have rods with the .927 pin but I think they're obsolete too.
You'll have to do some searching to see who has what to build one. Not sure what's out there anymore.
Delkron was offering the pushrod relocation service but I think they're out of business. I thought they had a Wiseco piston for that setup too but don't quote me on that. It's been a while.
Jim's used to have rods with the .927 pin but I think they're obsolete too.
You'll have to do some searching to see who has what to build one. Not sure what's out there anymore.
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
A 'fatvo' never appealed to me, but having stroked my Evo to 89" some years ago I did start to fancy even more cubes after a while. The disease can take some curing once contracted! To go to a larger bore really needed aftermarket cases, but by the time I decided to investigate, what I found is that some of the popular brands had either disappeared, or stopped making cases and larger cylinders. A great idea quickly came unstuck!
You seem to be following a similar path, looking into something that was popular a while ago but has slipped into the annals of history. I did eventually decide that I needed to act back in 2008 and found that an S&S engine is most satisfactory! I bought a 107", since replaced by their 111". So if that scratch won't go away.....
You seem to be following a similar path, looking into something that was popular a while ago but has slipped into the annals of history. I did eventually decide that I needed to act back in 2008 and found that an S&S engine is most satisfactory! I bought a 107", since replaced by their 111". So if that scratch won't go away.....
Banned
Joined: Sep 2009
Posts: 3,569
Likes: 624
From: deland,florida
did a lot of heads for them back in the day,made a fixture for doing the P/rod holes (not even sure if I have it anymore,may have used it to make another fixture or something),been a while since I used it
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Road Master
Joined: Sep 2007
Posts: 1,045
Likes: 74
From: AB, Canada
I'm building one right now.
S&S 4 5/8 crank in a Sputhe case. Stock HD 103" pistons and cylinders, 110 SE heads.
Had to get the pistons machined for non tapered rods.
S&S 4 5/8 crank in a Sputhe case. Stock HD 103" pistons and cylinders, 110 SE heads.
Had to get the pistons machined for non tapered rods.
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Road Master
Joined: Sep 2007
Posts: 1,045
Likes: 74
From: AB, Canada
Found that the pistons also need to machined for clearance at BDC. I decided to swap to a set of 010 over Wiseco forged pistons with 3cc domes for a little bump in compression plus they have much larger valve reliefs for the 2.08 110SE heads. Means i now have to have my cylinders bored though. Might as well set my deck to 0 also then. $$$$$$ keeps adding up.
I'm currently trying to figure out how the hell to measure / calculate how much has to be removed from the skirt of each piston. I can find information about this application.
I'm currently trying to figure out how the hell to measure / calculate how much has to be removed from the skirt of each piston. I can find information about this application.