Replacement engines for Bristol 6

[Claude]

On the other forum, someone posted a notice for an Ebay 401 with a Ford 6 engine, which prompted some discussion. Among the chat was this comment:

"Prewar BMW blocks aren’t all that tough to find if you’re in Europe…and I know of a rebuildable EMW unit in NH that’s available for a reasonable sum. The 328 style head is the killer, though they’re available new at about $10K apiece. I’d be tempted to install more modern BMW based mechanicals such as the M42 4 cyl, which is almost exactly the same length as the original engine and would provide sufficient power to move the car smartly, yet not completely overpower the thing."

So, any comments about a BMW M42 engine fitting as a replacement? It certainly would be the right provenance.

Claude

[RGSchmitt]

"Free of corrosion" perhaps by midwestern
standards, or just not poking deep enough.

[Hydroglen]

It's been for sale before but no takers at the price. Bristol engines and
gearboxes are available if one wanted to do it right.
Dorien

[stewart w]

Hi,

Not sure if the web site www.bmw328.net has been commented upon in previous correspondence. But prices of engine spares are listed and of course the downward slide in the £/euro rate has not helped, but the head is listed at 8400 euro!!

Interesting site nevertheless.

Regards
Stewart

[dave dale]

401 was sold a few weeks ago with a 2.8 litre Nissan engine and 5 - speed box.

http://www.angliacarauctions.co.uk/31447/35445.html

Dave Dale

[Kevin H]

I don't think I could own that car. Can you imagine telling people it has a Nissan engine...

A BMW engine maybe, but nothing else.

Sadly if the cost of restoring a 6 cyl Bristol car exceeds the value of the restored car, then the high value of Bristol engines means that more 6 cyl Bristols are likely to be bought purely for their engine and transmission, which means the cars may ultimately end up on the scrap heap.

Ironic that Bristol's supply of engines and chassis to other manufacturers should result in the destruction of Bristol cars. Maybe Bristol should have listened to Harold Aldington and made sports cars!

[geo]

Originally Posted by Kevin Howard

I don't think I could own that car. Can you imagine telling people it has a Nissan engine...

A BMW engine maybe, but nothing else.

Hang on a minute Kevin, I do not know about that engine, but quite a substantial amount of BMW kit is manufactured by their partner company, the Bermuda-registered Brilliance China Automotive Holdings Ltd. (the company with which the late Rover first hoped to jump into bed).

Brilliance might only have produced thirty-odd thousand complete BMWs in 2007, but planned to increase this to 100,000 by next year.

[Kevin H]

To be frank I simply wouldn't have a 6cyl Bristol with anything other than Bristol engine. The same goes for any other classic car. I just can't see the point.

But if you must replace the original Bristol engine in an aerodyne I'm sure an older German made 6 cyl BMW engine could be obtained quite easily.

[Ashley James]

I must say that I worry for old Bristols because they really are
neglected. My son was workshop manager at www.alpineeagle.co.uk
where they regularly rebuilt cars for more than double their value.
I don't think the owner would appreciate me telling how much it cost
to restore a Gurney Nutting PIII, but the engine alone was about £80K!

Brian May has quite a few projects that require total rebuild and for
which there is little or no interest. I think I'm one of only a
handful who've completely rebuilt a 400. It's very sad and I don't
think it is so much the cost, which is considerable, but that
collectors are virtually unaware of them. Surely a decent 400 wouldn't
look out of place at Pebble Beach, it is quite distinctive enough, but
it has never happened.

I own a Bentley MKVI and they've been neglected for years, but in the
last ten or so, people have been spending considerable sums of money
on them and their condition has improved significantly. Rich is
currently doing a total interior restoration of a 400 but before that
it was a straight run of Bentleys.

I do hope some of you will shoot of to see Brian and save a few cars
that otherwise I'd be very worried about.

Ash

[406Special]

Given that a highly desirable and market driven demand for classics
will determine their value in original condition, it is apparent that
Bristols, as of this date, are not in the same category as say
Ferraris and other classics. I agree with everyone's sentiments so
far, but must also say that due to the cannibalising of Bristol
sixes, notably from the 406 model in favour of AC Ace, or Frazer Nash
cars due to their higher market value, is it not better that some of
these cars (Bristols) at least live longer and provide joy and
satisfaction to their owners irrespective of whether they are Bristol
powered or not. Further, until recently, although still largely
true, you could not buy a new motor, or in the earlier cars case, a
new gearbox. Take the Fiennes engineering company next door to
Alpine Eagle as an example. They build everything new for your
Bentley/Rolls if you need it - expensive but it's available.
Similarly the cost of the new Bristol six blocks and heads implies
that one would want to see market values increase dramatically to
justify the investment - or take a long term hope that they will
improve.

I do agree not just any motor should be planted inside a Bristol.
Indeed, rather than simply state it should be BMW just because of the
historical provenance of the original chassis and mechanics, one
should consider the fit, the cost, the weight, the performance, the
character and the general availability of spares for the
replacement. Being someone who has undertaken a long and hard review
of engines pre-2000 and post say 1985, their are a range of small to
medium V6's, big inline 4's and a handful of smallish lightweight
V8's that could be employed. Further to make the job easier to fit
into the criteria I've just mentioned, you must also look at
electrical matters as well as whether the donor car was RWD or FWD.
Sticking to RWD for a donor car severely limits the choices and yes
BMW remains top of the list. I even bought a 2003 2.5 litre six from
an early E46 model car and with the gearbox it was too long without
fouling the front cross member and steering rack, or needing a major
set of work to rebuild the entire bulkhead and even then the gearbox
would have been too far back for ease of use. I had to abandon that
idea pretty quickly and sell it on (at a small loss).

My final decision, although not a purist one, in as much it is not
BMW, is a relatively common, reliable, strong, easily fitted, perfect
weight, easily tuneable, Volvo red block motor. Using Penta marine
crank, Mahle pistons, forged H-beam rods, Garrett turbo and a host of
other improvements, mated to its original Getrag 5 speed box, it is
ideal for maintaining the same weight distribution, providing more
than adequate power and torque, whilst being pretty inexpensive to
maintain and support if things go wrong - almost anywhere given the
availability of Volvo bits. For me it will be my car and thus a
special, complete with improved brakes, seating, climate control and
other stuff. It will cost much more than it is probably worth, as
does every Bristol full restoration, regardless of who does it. It
boils down to personal choice. My car will be an Alpine Bristol,
thus differentiating it as a special - a Bristol modified and
improved by Alpine (Eagle) - although to my specs. Pity I've been
waiting several months for my motor to be built!!!

As to whether or not a 2.8 litre (long) Nissan motor is a good choice
I am not sure. Certainly it is an iron block motor and thus probably
a lot heavier than the original 2 litre six. Unless it has had
brakes improved and a few other items it may even be unpleasant to
drive, however the description is not complete enough for a full review.

Clyde