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Re: 1796cc Engine Build

Posted: Fri Jan 11, 2008 9:05 am
by Merlin
That looks badass. :mrgreen:

Reminds me of '80s/early '90s BMX chainrings. :lol:

N.

Re: 1796cc Engine Build

Posted: Mon Jan 14, 2008 1:39 pm
by Merlin
Calooker wrote:The block has now been cleared to take the crank and it now turns, rods 1& 2 rod area in block also cleared and fitted to crank are turning need to do rods 3& 4 in block, as well as trimming the back of the pistons and thinning the skirts as they are touching the counter weights.

The centre main bearing housing needed about 1.5mm of material removed to clear the cheeks of the crank, plenty trial fitting and grinding. Will have the short block finished by the weekend.

Re: 1796cc Engine Build

Posted: Mon Jan 21, 2008 11:14 pm
by 2BugMe
Hey Cal,

So you not building a 1776 anymore - with you buying 4Age's 90.5 pods and pistons???

Good luck man, hope it brings you joy... :wink:

Re: 1796cc Engine Build

Posted: Tue Jan 22, 2008 7:15 am
by calooker
90.5's for another future project.

Re: 1796cc Engine Build

Posted: Wed Jan 30, 2008 10:02 am
by calooker
Here is some of the clearancing done, bearing carrier had to be thinned to accomodate the crank cheeks, the area next to the sleeve opening has also been radiused to clear for the longer stroke.

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Above and below the sleeve opening had to be notched to clear the rod bolts.

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Re: 1796cc Engine Build

Posted: Wed Jan 30, 2008 11:09 am
by calooker
Forged 76,4 crank that will be duing duty on the front line.

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With the clearanced rods attached.

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Re: 1796cc Engine Build

Posted: Wed Jan 30, 2008 11:17 am
by calooker
These rods have been cleared to eliminate too much clearing of the engine case and weakining it.

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These show how far it can be taken, but no more.

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Re: 1796cc Engine Build

Posted: Wed Jan 30, 2008 11:27 am
by calooker
OEM sleeve has been machined to 1mm oversise.
The valves have also been unshrouded to match the larger bore 86.5mm. I have done some re-shapping of the chamber to aid flow, the step was also flycut and a 49cc combustion chamber was the result, final CR will be between 8 to 1 and 8,5 to 1 (TBC)
Don't ask the head is not cracked between the valves it was a mark left by the milling machine during operations.
The valves are stock size 35x32

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BTW there is no need for the polishing in the combustion chamber, all that is needed is smoothness with no sharp edges.
That "chrome look" shine that many modifiers do and claim adds to HP is totall bull 30 seconds into the run-in and all that shine is gone.

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Note the cross hatch of the walls essential to keep rings happy.

Re: 1796cc Engine Build (Pics added)

Posted: Wed Jan 30, 2008 11:43 am
by calooker
Inlet ports have had some reshaping done, again no "chrome look" shine here, as many do, just smooth no rough edges. I used my round port template and straightened the port directing flow directly over the valves.

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BTW OEM valve springs to be replaced with HD singles as soon as they arrive from the US.

Re: 1796cc Engine Build (Pics added)

Posted: Wed Jan 30, 2008 12:39 pm
by calooker
The dudes in the US puting 84mm strokes into OEM cases have balls, I beleive if things get too thin they break, luckely no clearing needed on the case roof, but it's close.

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Re: 1796cc Engine Build (Pics added)

Posted: Wed Jan 30, 2008 1:21 pm
by calooker
The Kadron manifilds needed to be notched to fit the heads

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They have also been port matched

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Re: 1796cc Engine Build (Pics added)

Posted: Wed Jan 30, 2008 1:25 pm
by calooker
The resized cylinders have also received a lick of black hi heat paint, even if the paint does nothing, at least it looks better than seeing the rusty fins

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Re: 1796cc Engine Build (Pics added)

Posted: Wed Jan 30, 2008 2:11 pm
by 2BugMe
Hey Cal,

Looking good man.... :hangloose:

Wat heat paint did u use on those pods??..looks great

Happy building...

Re: 1796cc Engine Build (Pics added)

Posted: Wed Jan 30, 2008 2:20 pm
by calooker
I use heat resistant Plascon in a aerosol can about R45 a can from the local Pick'n Pay