Has any one tried building a TR6 motor with a GT6 crankshaft? It seems to
me you'd be a little lower on low end torque but gain high end power. this
was the case with the Jag motors when they went from 3.8 to 4.2 liters.
I've been think of doing this since I really could use the RPM's in the
class I run in, mostly big block Chevy's and Fords and a few Porsche 911's.
Charly
----- Original Message -----
From: "John Price" <jprice1@txcyber.com>
To: "Friends of Triumph" <fot@autox.team.net>
Sent: Tuesday, May 18, 2004 5:25 PM
Subject: Re: Crankshafts
> Ron:
>
> If you haven't read Kas Kastners dissertation on TR-6 crankshafts, you
> need to. There is a harmonic in the crank that occurs in the 6-7K rpm
range.
> It is a function of the design of the crankshaft and going to a billet
crank
> will not eliminate it. The bottom line is that even if the crank doesn't
> break, the vibration will destroy lots of other bits in the engine. Smart
> TR-6rs limit reve to 6000 rpm.
>
> John Prie
>
> ----- Original Message -----
> From: "ron meek" <rmeek8@juno.com>
> To: <fot@autox.team.net>
> Sent: Monday, May 17, 2004 11:02 PM
> Subject: Crankshafts
>
>
> > Hi all,
> >
> > So I'm thinking of the next TR-6 engine I'll be building for Walt
> > Holowell and I'm wondering what the crankshaft options are,
> > besides Moldex (c'mon Walt, buy me a Moldex).
> > His current combo runs a stock crank and rods (polished,shotpeened,arp
> > bolts) and has put down 135rwhp which should him at
> > about 170-180 at the crank(I figure his od tranny is responsible for a
> > few extra percent loss even though it's not engaged on the
> > chassis dyno).
> > I'm no Triumph expert, so at what point does the stock crank become a
big
> > liability, I expect this engine to rev to 7000-7200 rpm
> > and hopefully put out about 210-220 at the crank,is this too optimistic?
> > Since Walt attends southwest regional events and does not chase national
> > points I don't want a short fuse, what will be the expected maintenance
> > intervals on such an engine(rings,bearings valve guides)?
> > Probable combo: Pauter rods
> > PRI cam and lifters
> > 12:1 JE or CP pistons
> > Big valves and lots of porting
> > Goodparts roller rockers and tubular pushrods
> > well baffled sump as per current engine(3 trap
> > doors courtesy of Stanley door hinges)
> > 40mm DCOE's or possibly PRI's Keihin setup
> > Did I miss anything Walt?
> >
> > All input would be very welcome.
> > Ron Meek
> > Alb. NM
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