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Special engine modification

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I really don't have anything bad to say about welding up and reworking pistons in a pinch, BTDT. I don't, however, have anything good to say about this dudes workmanship.

Really, I've seen some pretty strange combinations over the years. One ongoing possibility I have been looking into is that of bolting a BMW bike head to a BMC/Leyland A series. They tell me it ain't all that difficult. Now I just gotta figure out WHY.

Rod
 
Rod,

It is true that you can get the head from a a BMW K series motorcycle engine to fit onto an A-series block. The bores and 3 of the head studs are a perfect match. This is in itself fairly remarkable but does leave a number of engineering challenges.

A good friend of mine is doing just this to power his Austin A30, so if you really want more information, I can help. He is by no means the first to do this.

As to why..... well it has to do with the regulations of some UK racing series that specify the original style block must be used but leave you free to choose alternate heads. DOHC +16V promises a little more power and torque without having to rev the thing too hard. He hopes....

Personally I'd have just put something more powerful/modern in as a complete lump and chosen a different race series...

As to that piston mod - I guess the principle has something going for it. The execution leaves alot to be desired though!

Nick
 
an old trade teacher told me,
he had a mini with a u/s piston and he wanted to sell the vehicle but was low on cash.
he made a wooden one on a lathe and he reckons it ran well enough to sell

the pics on that forum reminded me off it........
 
nobbie, that's even a bit over the top for even my intemporate youth....
I put a cantaloupe in the dead cylinder of flathead Ford, I put sawdust in the gearbox of an early Ford, bannana peels in the differential of another early Ford, plus some other odd and illegal tricks in order to get cars to pass Texas safety inspection so I could sell them. In college, I bought and sold cars, mostly bought from Ft. Bliss GI's and sold to Juarez, Mexico.
AND, no I don't feel guilty any longer. I do pay close attention to cars I buy, though.

Rod
 
My lawnmower (Honda sidevalve) has a cornflake packet head gasket. This was intended as a temporary " maybe this will get me going" type of bodge when stuck with a half mowed lawn. It's done 3 seasons so far, which is a surprise (most of that on E85 which may or may not be significant). Price Honda want for a new gasket I'll probably just reach for another cornflake packet when this one fails!

Why the cantaloup Rod? (Guess we know where the "evel" comes from now.....? :))

Nick
 
I'm guessing the cantaloupe was to keep fuel air mix from passing through the dead cylinder... depends on how the cyl was "dead" though. I'm imagining a conrod BE sawed off at the shoulders installed on the crank to keep oil pressure? Of course if the valves were any good you could have just rounded off the cam lobes for that cyl on a lathe instead of removing the recip assembly and replacing it with a cantaloupe, but then you'd still have the friction of the piston going up and down for no purpose.
 
I knew a guy once that removed the rod/piston assy from one cylinder of his 170 CID ford 6, clamped a chunk of inner tube around the crank throw to hold the oil pressure. A little down on power, minor roughness at idle. Oh yeah, he removed the rocker arms & installed a spacer on the shaft. Ran for years like that.
 
I recall my father feeding nylon tights (panteeee hose) into the gearbox of a '65 Hillman Super Minx.

- Steve
 
Can we move this thread to the "True Confessions" forum?

rmw
 
When overhauling a 225 slant six for my Valient, I misplaced a pushrod. Best I could do at the moment was take two pushrods from the old 170 and lay them next to one another displaced by 1" and weld them together. It ran. Eventually I replaced it with a proper one, I believe. Another time, my Ford 390 had worn the breaker points rubbing block to where it wouldn't adjust enough. A tire iron was enough to adjust them for further operation.

Jay Maechtlen
 
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