Seems it would be easier to have a special pulley made for the crank rather
than the route he is taking.
My 2 cents,
66 Mike
----- Original Message -----
From: Gordon Glasgow <glasgow@serv.net>
To: datsun-roadsters@autox.Team.Net <datsun-roadsters@autox.team.net>
Sent: Sunday, July 30, 2000 8:33 PM
Subject: Re: 2000 timing chains
> Actually, Craig Hooper has been having a guy build exactly that for some
time now. Part of the
> motivation for the switch (as I understand it) was that he wanted to run a
belt-driven supercharger.
> The engine has been dry-sumped and the belt is external. Besides the
fabrication difficulties, I
> think the biggest drawback is that it requires cutting the front portion
off the head, thus
> rendering it unusable for a regular U20.
>
> jerry gallagher wrote:
>
> > I've been on the roadster list for about 7 years and have seen many
posts
> > about the 2L timing chain setup. I've been wondering just about as long
if
> > there are any alternatives.
> >
> > So I'm going to contribute this free idea and perhaps my flawed
knowledge of
> > things automotive will be brought to light(not too much risk of that not
> > happening with this group but hey this is roadster related so be gentle)
> > and I can spend my time thinking of other things.
> >
> > 1.) the 2L's performance seems to suffer from the weight of two timing
> > chains and four timing gears.
> > 2.) many newer cars have timing belts. A belt of the same length weighs
> > much less than a double-row chain
> > 3.) many racing Alfas use a single row chain instead of the normal
> > double-row chain. Has anyone ever heard of a 2L running a single row
chain?
> > 4.) with the abundance of cars using timing belts these days is it
lunacy
> > to think that out there somewhere there is a combination of timing gears
and
> > timing belts and tensioners that could be adapted to the 2L to perhaps
> > lighten the valve train and increase performance. Perhaps there is a
> > permanent solution to the 2L death rattle waiting to be found out
there --
> > maybe it would cost less the replacing the timing
> > chains/tensioners/gears/guides with stock parts.
> > 5.) the biggest issue I can identify about this being possible, making
the
> > assumption that item #4 is true, would be how to create a dry
environment
> > for the belts since oil and timing belts are not a good combination
(there
> > are some things you don't want to slip).
> > 6.) If I remember correctly the reduction from crank speed occurs
between
> > the crank and the jackshaft. The jackshaft to cam is a 1:1 ratio.
> >
> > Am I volunteering to use my own car -- no. I rebuilt the engine 8 years
ago
> > and the car gets about 1,000 miles a year -- probably less this year
since
> > I'm using my Alfa gtv6 as my daily driver. I fully expect the stock
setup
> > to last quite a while -- bought everything new from a Nissan dealer,
right
> > down to new lock tabs for the tensioners.
> >
> > going to get the nomex on now (former racer? no, used to own a pinto)
> >
> > hope you all have a good weekend
> >
> > Jerry
> > '69 SRL311 xxxx7
> > '86 alfa romeo gtv6
>
> --
> Gordon Glasgow
> http://www.gordon-glasgow.org
>
>
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