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Subject:Re: performance engine question
Date:Thu, 4 May 1995 10:43:53 -0700

>I am about to send my stock 1600 case to the shop.  I was thinking of getting
>a performance rebuild kit  It will be a 1776 stock  kit with a 110 cam
>substitution.  The Heads will have 39mm intake and 32mm exhaust valves all
>with heavy duty springs.  My question is,  will my compression ratio be all
>messed up and will I need shims to clear up this problem. if I need shims how
>do i know what size.    Thanks for any help.
>Tim
>Flagstaff, AZ
>I don't want a race car just more power
>1971' 1600? bus

Yes, you need to correct the compression ratio or you'll have a hot engine.
You find the size out by checking the piston top deck height, (usually about
.060"), then cc'ing or guessing your head cc's (stock is usually about
50-52cc) then doing the calculations for CR.  (Head cc+ deck cc + shim cc +
cylinder cc)/(Head cc+ deck cc + shim cc).  I seem to remember using a .120"
shim for the 90.5mm x 69mm cylinder kit.  Your intake and exhaust manifolds
may not line up correctly because of the added engine width, almost a
quarter inch.  I set my engines up with 6.8 CR and run dual single throat
carbs, Dellorto FRD or Kadron.  Time at ~12 BTDC and they run cool and
strong.  Watch that valve train, it'll be noisy and wear parts out if you
don't keep on it.  Pre-lube it well before start-up.  Hope this is a new or
at least an AS21 case.

Eug,
'71