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ul flywheels in VL

Moderators: Curt!, Pa

Post Sat Dec 09, 2006 1:14 pm

Posts: 75
Location: Breda, Netherlands
My Vl cilinders are resleeved with UL sleeves. So the engine now is 69 cu. I will use UL flywheels with a longer stroke to get 74 cu.

I already have both the (150-372 and 150-374) flywheels. The Vl pinion shaft and VL driveshaft wil fit. The crankpin of the Ul is larger than the Vl.( O.D.=1.124" vs O.D.=1")
I searching for a set of Ul rods ( ZA705, ZA706), but they are very expensive.

I wonder if I can use the VL connecting rods ( SA705, SA706) with I.D. 1.1/2"" by using the Ul crankpin and 3/16" rollers. By calculating this would fit.

anyone known if this can be done and wich roller retainers does fit this setup?


Post Sat Dec 09, 2006 11:18 pm

Last edited by panic on Sun Dec 10, 2006 5:40 pm, edited 1 time in total.

Post Sun Dec 10, 2006 10:20 am

Posts: 634
Location: Wisconsin, USA
Panic you are a funny guy. Are you rounding up to get your one onehundred thousanths of an inch figures? I can only imagine the degree of "feel" a person would have to have to accurately and consistantly measure to that extent with a conventional micrometer. I have a premonition that I am soon to be enlightened by one of you master machinists as to how this is done. Really tiny threads?

Post Sun Dec 10, 2006 11:47 am
Pa Site Admin

Posts: 5547
Location: Ohio USA

I can still feel the fourth place decimal. :wink: I guess at the fith. :wink: Pa

Post Thu Dec 14, 2006 1:17 pm

Posts: 20
Location: FINLAND
Hello It can be done U flywheels,SA rods.You have to shave flywheel od down little bit,grind oil passage to the pinion shaft because different oil hole location,use early U-crank pin 37-39 fabricate roller retainers,no factory retainer availeble(not easy,take a look at late aluminium retainers as a guide and make smaller one we done it aluminium-bronze,use good machinist)You need stroker plates,or pop-up-relief to the head.pop-up is better.Pinion gear timing mark is 5 tooth off(advance cams)Female rod shoulder will touch baffle,trim this also.We have done this with 54%balance factor .It is smooth and just as strong as any 80" BT flatty.I hope this helps.....RUB-BOY

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