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Re: [Fot] TR8 direction

To: Shawn Frank <my71spit13@yahoo.com>
Subject: Re: [Fot] TR8 direction
From: Duncan Charlton <duncan.charlton54@gmail.com>
Date: Wed, 12 Dec 2012 14:17:13 -0600
Cc: "FOT@autox.team.net" <FOT@autox.team.net>
Delivered-to: mharc@autox.team.net
Delivered-to: fot@autox.team.net
References: <1355323775.66227.androidMobile@web112515.mail.gq1.yahoo.com>
The engine will respond to tuning. I recall that the TR8 had a low compression
engine, a less-than-ideal intake manifold, and a smog camshaft.  Throttle
response is greatly improved with a bump in compression and an Edelbrock carb
and intake manifold.  There is a lot of advice on the 'net about improving
performance in these engines, which are the UK equivalent of the 350
small-block Chevy engine as far as performance experience and practice.

Our 1971 Morgan Plus 8, which started life with a 3.5 Rover engine (10.25:1
compression ratio), had a rather wheezy salvaged TR8 engine in it when we
bought it in 2003.  The Morgan now has the same basic BOP/Rover engine but a
higher compression ratio (9.35:1), an Edelbrock/Weber/Carter carburetor
(easier setup than the Holley -- after all the tuning checks I ended up having
changed nothing but the idle mixture and speed) and manifold, a Piper 272
camshaft and coated headers from a later Plus 8.  I did port-matching only on
the TR8's SD1-spec heads.  It retains plenty of low-end torque but it will
wind out to 6000+ rpm if one wishes.

Want more power?  Rover Vitesse heads would be the best stock heads (unless
you want to get fancy and use a set of aluminum 1964-only Buick 300 heads;
they breathe well -- you'd need to jigger the intake manifold fit and use
different exhaust manifolds).  There are a couple of aftermarket heads out
there (Wildcat is one) but I'm not convinced they are worth the money and
trouble yet.  There are production versions of the BOP/Rover engine in 3.9
liter, 4.0 (those two share the same B/S but blocks are slightly different),
4.2, 4.3, 4.4, 4.5, 4.6, and 5.0 liters but several of those sizes would be
hard to find in the US, having been used on TVRs and some Australian cars.
The 4.0 and 4.6 injected engines are pretty plentiful and are found in Range
Rovers.  Probably with what amounts to an RV camshaft, though, better to lug
all that weight around.  The 4.6 will give 225 hp and 280 lb/ft of torque, not
bad given the TR8's weight.

Or if that's not enough, upgrade to a 5.2 liter version of the same engine
with a little help from RPI.  Use the 3.5 front timing cover if you want to
stay with a distributor instead of crank-triggered ignition.  Not sure what to
say about your transmission's reliability, though!

Duncan
(Texas)
On Dec 12, 2012, at 8:49 AM, Shawn Frank wrote:

> It is a 1980 convertible, green, with AC. It is a very nice find for the
> price, and would not take much to get it on the road. Should we do an
> Edelbrock manifold and carb?   Shawn
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