Author Topic: F2 head on a K model.?  (Read 1224 times)

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Offline Retro Rocket

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F2 head on a K model.?
« on: June 01, 2015, 03:31:28 PM »
Hi all, I have an F2 head for sale and was asked what was involved in making it work on a K model engine, someone recently gave me this information but i can't find the thread, could someone please help.. ;)

Thanks
750 K2 1000cc
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If You can't fix it with a hammer, You've got an electrical problem.

Offline jweeks

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Re: F2 head on a K model.?
« Reply #1 on: June 01, 2015, 06:57:22 PM »
Sleeve 4(?) cylinder head bolt holes to match the K head and no more oil will fall onto the cylinders. Bigger domes on the pistons for the bigger combustion chambers optional. Hope it's being planned for a big cc motor. Bigger ports on the F head likes big pistons and more stroke. I like the F head for 1,000 cc +.  Hope this helps.  ;)

Offline Old Scrambler

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Re: F2 head on a K model.?
« Reply #2 on: June 01, 2015, 07:26:23 PM »
+1 on the sleeves around the studs that have the acron-nuts on the 410 head.  Also use new or annealed copper washers.

I use the F2 head on a K4 motor with 62mm high-compression pistons (762cc).  I was warned that it may not flow very well, but my dyno-chart says it will pull past 11,000 rpms and has 78 RWHP...........maybe more when we get an improved exhaust system.
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Offline cbr954

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Re: F2 head on a K model.?
« Reply #3 on: June 01, 2015, 07:54:25 PM »
Kenny at Cycle X will do the brass sleeves and I had Jay at APE do mine so he knows how to do them now also.
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Offline Retro Rocket

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Re: F2 head on a K model.?
« Reply #4 on: June 01, 2015, 08:44:41 PM »
Thanks for the replies guys... ;)  I was going to use it on my 1000cc billet block but i already have the forged pistons to suit the K head, so i'm going with the 392 head in stage 4... ;)
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.