David Kernberger wrote:
Peter--in your first sentence,did you leave out a second number? Was it
1.7 ?
Reply: Yes it was 1.7, it was a typographical error.
Lar Kaufman wrote:
As for the cost barrier for the stroker kit, was there a particular
reason you ruled out a machined Buick 350 crank? I'd trust one if
it were nitrided/tuftrided before use; you could have one machined
to spec, treated, and shipped out from the US for a fraction of the
cost of the Prostroke kit... and it appears that only a smidgen of
clearancing of the block is needed.
Reply: The Prostroke kit includes a P76 crank (modified to fit a
Rover/BOP block), rods (resized & reco), pistons (machined to produce
your desired comp), rings, bearing set, and the whole reciprocating
assembly is finely balanced. Given component prices in Australia, I think
it is good value at AU$1800 (US$1134). The nearest equivalent here, a kit
from Triumph/Rover Spares in South Australia (which uses a 3.4" crank)
starts at AU$3050 (US$1921). The reason for using the P76 crank was
because they are common and cheap here.
Gregory72@aol.com wrote:
Kurt Schley of the MGB V8 Newsletter was kind enough to put me in contact
with a couple from Australia with a vast knowledge of the P76\Buick\Rover
V8.
Like it or not, this is what they have to say. It's long, but
interesting.
I'll keep them annonymous for now.
Letter from Down Under - Part 1
Letter from Down Under - Part 2
Reply: This sounds very much like Roy & Judy Gardener. The essence of
their comments that are pertinent to the discussions on this list are:
The P76 cranks are prone to premature mains wear and do break.
The P76 blocks are prone to breaking or throwing a mains cap, and to
loosening of a sleeve.
The comments regarding head bolts, valve shouding, and valve oiling have
been covered elsewhere and are well known.
I became interested in P76 engines when looking for a torquey upgrade for
my tired Rover P5B.
I couldn't bring myself to pay AU$3050 for a kit and so talked to
everyone that I could contact in Australia who had reputation for
P76/Rover knowledge. Roy was the only person who mentioned P76 cranks
being prone to premature mains wear and breaking. In high stress use in
Range Rovers and in racing I heard stories of mains and blocks breaking,
but not of cranks breaking or prematurely wearing. I have spoken to a
number for folks running 'enhanced' P76 engine in street cars and none
have reported these problems. It's possible that it happens, but I
haven't been able to get other people to confirm it. The standard Rover
mains is smallish for a 3.5" stroke, but almost all kits run with the
standard Rover mains size. Ian Wilson at Triumph/Rover Spares (3.4"
stroke) said that they build an engine a week (he's been selling this kit
for more that 4 years),that many of these engines now have done more than
100,000 miles and that they have never had a problem. It is possible that
the P76 is made of inferior quality material but without metallurgical
analysis, I don't now how to assess this. In the real world, without
widespread reporting of premature mains wear and breaking, and in
everyday use in a street car it may not be a reality. Because of this I
approached ProStroke to build a P76/Rover test engine, and they like the
result so much that they are going to make it as a kit. Nitriding the
crank is an optional precaution.
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