Combat heads questions

Sad to say but hobot gave some of the best advice on this one. As to swooping in and being a pompous ass some of us do have a life other than this forum but when I see such ignorant answers as especially the first one I pointed out they have NO business on here giving it out. About having a lathe you don't need one to do what I stated as every machine shop in town has one and an operator than will be capable of such a simple job. And to your spacer plate and 2 gaskets it will work BUT good luck with keeping it tight and leak free in the long haul. I prefer to do it better than a bodge

hobot said:

Dang if it was mine I'd keep the Combat head's high CR and stick in a 2S cam to prevent detonation and get the Combat off idle beyond redlined spunk. If so then would want to get the shortened push rods to center the rockers on the stems. W/o the hi CR and the more aggressive 2S cam the CHO head is over ported so may end up with ho hum response till upper rpms but w/o the torque rise of 2S packing mix in.

No difference in standard or Combat pistons, both flat topped and in my Combats they stick up proud of deck by .050", if no base plate under the cylinder.

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pvisseriii said:

We're not worthy, we're not worthy.

For Christ sake bill, not everyone has your expertise and a lathe in their basement.
The poster simply needed some information. I had experience in this particular situation and what I did work well for me, period. A gasket on either side of the spacer is not a sin, neither religiously nor mechanically.

I can offer you and others like you some advise: Offer your experience, advise, and wisdom rather than wait for others to offer what they have only to have you swoop in and criticise.

If you can help a person out, then help a person out. If you feel you are protecting the individual by being a pompous ass, it isn't working. It only goes to show that, in fact, you are a pompous ass.

Sorry L.A.B.

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ugh, ain't nothing like the bickering among same family members to show how much ya care eh.

Its the cam shaft installed that must be pleased with figuring what CR to seek. If standard cam better stay well below 10 CR but if more aggressive cam bump CR up to 10 or more as over lap cam lowers effective CR in the low rpm ping prone zone, then packs it in when rpm too fast for detonation to beat piston decent. Diddle timing to just short of back fire on initial advance and feel the Norton shoving ya into the future. I found the base gaskets tend to pound down to mush and leak so extra re-torque attention needed. Wes's '71 is standard engine but it pulls like my Combat to about 90 mph before the 2S/10 CR kicks in to get ahead. Wes's keeps pulling past the ton but ain't accelerating faster and faster like the Combat, which 90 mph with 19T is just getting spunky eager so hard not to keep on it beyond red line. i run 87 octane most the time and first year or so was pensive of detonation but didn't ever get any so now don't worry about it at all, even with the fast rise AAU pushing max torque pressure before TDC.

Rode Trixie Combat yesterday and for first time in 3-ish year did my commute w/o any drifting play getting to tarmac nor going faster than 70 or even grabbing full throttle running up gears, just delightful sweet sensations I'm still simmering on this am.

The time is long overdue the wheat is separated from the chafe on this forum. Problem is, some know not which category they belong in.

ha nice Jim - now thats funny - made my day! :mrgreen:

and like all great humor/sarcasm is based on truth

JimC said:

The time is long overdue the wheat is separated from the chafe on this forum. Problem is, some know not which category they belong in.

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