Discussion:
OT: glossy pin-up engine feast
(too old to reply)
bra
2018-05-18 02:13:12 UTC
Permalink
Sonny's Racing Engines is now selling a 13.4-litre CNC-cut billet block V-8 for marine use, that runs all day at 6500 RPM producing 1450bhpon pump petrol.

At 5,000-rpm it gives 1100 lb-ft of torque, so you just know you need this lump in your pickup truck.

Great glistening photos to drool over:

http://www.enginelabs.com/news/inside-scoop-sonny-leonards-new-820ci-marine-engine/

When was the last time you looked at a pushrod? Sonny's pushrods in this engine are 9/16 inch in diameter.

Now back to Formula E for those with a delicate constitution :-)
~misfit~
2018-05-18 02:50:28 UTC
Permalink
Post by bra
Sonny's Racing Engines is now selling a 13.4-litre CNC-cut billet
block V-8 for marine use, that runs all day at 6500 RPM producing
1450bhpon pump petrol.
At 5,000-rpm it gives 1100 lb-ft of torque, so you just know you need
this lump in your pickup truck.
http://www.enginelabs.com/news/inside-scoop-sonny-leonards-new-820ci-marine-engine/
Mmmm shiny tractor engines!!!
Post by bra
When was the last time you looked at a pushrod?
Must have been the 1980s. About a decade after the last side-valve engine I
worked on....

Unless we're counting lawnmower engines? Add about a decade or two to each
above if so. (I've been using Honda OHC engines for quite a while now and
never need to open those up - they seem to run for ever as long as you keep
up with oil changes.)
Post by bra
Sonny's pushrods in
this engine are 9/16 inch in diameter.
Hollow I take it? Titanium? Anyway size isn't everything.
Post by bra
Now back to Formula E for those with a delicate constitution :-)
Yep, there's a race in Berlin tomorrow. :)
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
bra
2018-05-18 15:58:02 UTC
Permalink
Post by ~misfit~
Mmmm shiny tractor engines!!!
Post by bra
When was the last time you looked at a pushrod?
Sonny's pushrods in
this engine are 9/16 inch in diameter.
Hollow I take it? Titanium? Anyway size isn't everything.
No, steel. The impossible chase for total rigidity in a compressed round-section bar when valve-spring pressures reach 500lbs. Some of the builders have started using solid TOOL STEEL for pushrods. Aluminum and titanium cannot stand up to the pressures.

http://www.jesel.com/valvetrain/index.php/rockers/pro-steel-series

http://www.jesel.com/valvetrain/index.php/lifters/solid-body

.
~misfit~
2018-05-19 00:32:50 UTC
Permalink
Post by bra
Post by ~misfit~
Mmmm shiny tractor engines!!!
Post by bra
When was the last time you looked at a pushrod?
Sonny's pushrods in
this engine are 9/16 inch in diameter.
Hollow I take it? Titanium? Anyway size isn't everything.
No, steel. The impossible chase for total rigidity in a compressed
round-section bar when valve-spring pressures reach 500lbs.
That's crazy! 500lbs valve spring pressures? That's the result of running a
pushrod engine at higher revs than the inherant design is easilly capable
of.
Post by bra
Some of
the builders have started using solid TOOL STEEL for pushrods.
Aluminum and titanium cannot stand up to the pressures.
Again, crazy (IMO).
Post by bra
http://www.jesel.com/valvetrain/index.php/rockers/pro-steel-series
http://www.jesel.com/valvetrain/index.php/lifters/solid-body
Rockers and lifters but no push rods?

The pic at the top of the first link bought back memories... I was on a
Sunday road-trip with a friend in a BMC (Austin / Morris) 1300 when things
started to go wrong in the engine. Luckily I had a few tools with me (I
always insisted on taking a small toolbag on trips longer than an hour or
two back in the pre-cell phone days) so we parked on the side of the road
and I started to investigate...

I thought about what had changed recently with the engine and knew he'd
recently had some work done by a professional <cough> shop in search of more
power - that was part of the purpose of our trip, to evaluate the modded
engine. They'd taken off the standard cylinder head and fitted it with the
head (and twin carb manifold) from a 1275 GT Mini. As well as the twin carbs
it also had higher compression, bigger valves and lighter valve gear - an
all-around better breather. They'd also fitted a re-profiled camshaft to
take advantage of

So going by that and the sound I took off the rocker cover and discovered
one of the rockers had broken off at the adjuster end, right above the valve
stem.

Here's what the original rockers looked like:
https://picclick.co.uk/Classic-Mini-Rocker-Shaft-A-Series-Engine-A-253608783463.html
and here's the 1275 GT rockers:
https://picclick.co.uk/Classic-Mini-1275-Gt-A-Series-Rocker-Shaft-282674120557.html
As you can see the 'new' rockers were made of folded steel with threads
through the adjustment end and that's where it broke.

That seemed like an odd thing to happen and we were at least 2 hours from
home out in the sticks so I had to jury-rig it to get us back.We decided to
go home on three cylinders. I pulled the pushrod (as it was no longer held
in place by the valve spring) and, as it was an exhaust valve, also removed
the pushrod from the inlet valve of that cylinder. I'd thought about
removing the spark plug but decided to leave it in place and leave an 'air
sping' in the cylinder rather than have the thing aspirate through the
(forwards facing) spark plug hole and suck in gods know what crap.

So we headed for home at a much reduced pace but less than halfway back
another rocker broke! I pulled the rocker cover again and, knowing now that
it wasn't an isolated defective rocker got to looking carefully at the valve
gear. Crouching down and studying the geometery it became obvious that they
rockers were canted too far towards the valves. At the bottom of the stroke
with the valve fully opened they were at an almost 45 degree angle relative
to the valve! The idiot "mechanic" who'd fitted the head had used the
original push rods which were longer than the ones the 1275 GT uses due to
the thinner cylinder head. I hadn't noticed the first time I popped the top
as it was only really obvious when sitting on the ground and peering through
the grille.

I ended up sitting on the side of the road pulling the rockers and springs
off the shaft and re-arraging them so that both broken rockers were over the
same cylinder and we could still run on three. I pondered my options which
weren't many with limited tools and no spares. I ended up putting the flat
washers from under the bolt heads that held the rocker gear in place between
the rocker pedestals and the cylinder head. I had to file some metal off a
couple of them to get them to fit. That obviously wasn't ideal but it lifted
the rockers a little and reduced the angle they were working on enough so
that we were able to get home on 3 cylinders without further breakage.

You can bet that I gave the mechanic an earful on the Monday!
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
bra
2018-05-19 01:09:11 UTC
Permalink
Post by ~misfit~
The pic at the top of the first link bought back memories... I was on a
Sunday road-trip with a friend in a BMC (Austin / Morris) 1300 when things
started to go wrong in the engine. Luckily I had a few tools with me (I
always insisted on taking a small toolbag on trips longer than an hour or
two back in the pre-cell phone days) so we parked on the side of the road
and I started to investigate...
Great story --- I am no engineer but I always thought those "folded" pressings looked very iffy for serious rockers. Good ones are forged, with rollers.
Your trip sounds like one an elderly acquaintance made over 60 years ago: he was a 15-year old garage apprentice near Northampton, who did a valve job on a Morris 8 on his own, watched by his boss. Because he was under age, Harry asked his boss if he'd road test the car. His boss said "No, but tomorrow I'm driving to Oxford and you're coming along. And bring your toolbox, because if anything goes wrong along the way, you're going to fix it." A good way to learn responsibility!
~misfit~
2018-05-19 10:56:22 UTC
Permalink
Post by bra
Post by ~misfit~
The pic at the top of the first link bought back memories... I was
on a Sunday road-trip with a friend in a BMC (Austin / Morris) 1300
when things started to go wrong in the engine. Luckily I had a few
tools with me (I always insisted on taking a small toolbag on trips
longer than an hour or two back in the pre-cell phone days) so we
parked on the side of the road and I started to investigate...
Great story --- I am no engineer but I always thought those "folded"
pressings looked very iffy for serious rockers. Good ones are forged,
with rollers.
Your trip sounds like one an elderly acquaintance made over 60 years
ago: he was a 15-year old garage apprentice near Northampton, who did
a valve job on a Morris 8 on his own, watched by his boss. Because he
was under age, Harry asked his boss if he'd road test the car. His
boss said "No, but tomorrow I'm driving to Oxford and you're coming
along. And bring your toolbox, because if anything goes wrong along
the way, you're going to fix it." A good way to learn
responsibility!
Thanks. Heh! I know what that's like as I tend to drive what I (re)build (or
these days more just maintain). Having grown up in the country and not
having a lot of money I've always relied on my myself for 'roadside
assistance'. I don't feel confortable without at least a few tools in the
car with me (and because of that I've helped quite a few strangers over the
years).
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
M2T
2018-05-19 09:17:05 UTC
Permalink
Post by ~misfit~
Post by bra
Post by ~misfit~
Mmmm shiny tractor engines!!!
Post by bra
When was the last time you looked at a pushrod?
Sonny's pushrods in
this engine are 9/16 inch in diameter.
Hollow I take it? Titanium? Anyway size isn't everything.
No, steel. The impossible chase for total rigidity in a compressed
round-section bar when valve-spring pressures reach 500lbs.
That's crazy! 500lbs valve spring pressures? That's the result of running a
pushrod engine at higher revs than the inherant design is easilly capable
of.
The engine builder is a former drag racer, they rebuild engines between
runs. Wear on cams, valve seats, etc isn't a problem in a sport where
engines are worked on until they explode!
b***@topmail.co.nz
2018-05-19 09:46:20 UTC
Permalink
Post by M2T
The engine builder is a former drag racer, they rebuild engines between
runs. Wear on cams, valve seats, etc isn't a problem in a sport where
engines are worked on until they explode!
Drag racing is somewhat different to the claimed application of a marine
engine. I am surprised that it could run all day at 6500 RPM when it is
over 100 cubic inch per cylinder.
~misfit~
2018-05-19 10:50:30 UTC
Permalink
Post by M2T
Post by ~misfit~
Post by bra
Post by ~misfit~
Mmmm shiny tractor engines!!!
Post by bra
When was the last time you looked at a pushrod?
Sonny's pushrods in
this engine are 9/16 inch in diameter.
Hollow I take it? Titanium? Anyway size isn't everything.
No, steel. The impossible chase for total rigidity in a compressed
round-section bar when valve-spring pressures reach 500lbs.
That's crazy! 500lbs valve spring pressures? That's the result of
running a pushrod engine at higher revs than the inherant design is
easilly capable of.
The engine builder is a former drag racer, they rebuild engines
between runs. Wear on cams, valve seats, etc isn't a problem in a
sport where engines are worked on until they explode!
Yeah but as bruce56 said this isn't a drag engine - it's supposedly for
marine use. I don't know about you but I've worked on an inboard engine or
two and they're not fun to lift in and out being in the middle of a boat....
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
~misfit~
2018-05-19 10:57:47 UTC
Permalink
Post by ~misfit~
Post by M2T
Post by ~misfit~
Post by bra
Post by ~misfit~
Mmmm shiny tractor engines!!!
Post by bra
When was the last time you looked at a pushrod?
Sonny's pushrods in
this engine are 9/16 inch in diameter.
Hollow I take it? Titanium? Anyway size isn't everything.
No, steel. The impossible chase for total rigidity in a compressed
round-section bar when valve-spring pressures reach 500lbs.
That's crazy! 500lbs valve spring pressures? That's the result of
running a pushrod engine at higher revs than the inherant design is
easilly capable of.
The engine builder is a former drag racer, they rebuild engines
between runs. Wear on cams, valve seats, etc isn't a problem in a
sport where engines are worked on until they explode!
Yeah but as bruce56 said this isn't a drag engine - it's supposedly
for marine use. I don't know about you but I've worked on an inboard
engine or two and they're not fun to lift in and out being in the
middle of a boat....
Oh wait - I guess they could be for racing boats where they're rebuilt after
each meeeting (or even race.)..
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
bra
2018-05-19 15:37:24 UTC
Permalink
Post by ~misfit~
Post by ~misfit~
Yeah but as bruce56 said this isn't a drag engine - it's supposedly
for marine use. I don't know about you but I've worked on an inboard
engine or two and they're not fun to lift in and out being in the
middle of a boat....
Oh wait - I guess they could be for racing boats where they're rebuilt after
each meeeting (or even race.)..
--
Shaun.
Did you know that, with twin-engine inboard boats, the engines are set up (cams, ignition etc) to run "opposite" each other --- one clockwise, the other anti-clockwise? They do this to balance torque reaction.

A racer in Oxford bought an ex-powerboat V-8 from Ford's main dealer on the Great West Road (alerted by a friend), who said that they had just received a pair of V-8 Mercury motors from an offshore racing powerboat, raced only once. 'Fred' bought one of the motors, complete / ready-to-run with all accessories, and he his mechanic hurriedly installed it in his race car before a weekend race. 'Fred' fired it up, put the car in first gear, let out the clutch --- and the car lurched BACKWARDS --- it had been the boat's left-side engine which, following standard nautical engineering practice for balancing a powerboat, it ran ANTICLOCKWISE, with the starter, cams, timing, etc all set up to allow that. So it was engine-out again and rebuild the whole damn thing before Friday.
~misfit~
2018-05-20 02:58:36 UTC
Permalink
Post by bra
Post by ~misfit~
Post by ~misfit~
Yeah but as bruce56 said this isn't a drag engine - it's supposedly
for marine use. I don't know about you but I've worked on an inboard
engine or two and they're not fun to lift in and out being in the
middle of a boat....
Oh wait - I guess they could be for racing boats where they're
rebuilt after each meeeting (or even race.)..
--
Shaun.
Did you know that, with twin-engine inboard boats, the engines are
set up (cams, ignition etc) to run "opposite" each other --- one
clockwise, the other anti-clockwise? They do this to balance torque
reaction.
Yes I did know that. (I'm a mine of 'useless' information.)
Post by bra
A racer in Oxford bought an ex-powerboat V-8 from Ford's main dealer
on the Great West Road (alerted by a friend), who said that they had
just received a pair of V-8 Mercury motors from an offshore racing
powerboat, raced only once. 'Fred' bought one of the motors,
complete / ready-to-run with all accessories, and he his mechanic
hurriedly installed it in his race car before a weekend race. 'Fred'
fired it up, put the car in first gear, let out the clutch --- and
the car lurched BACKWARDS --- it had been the boat's left-side engine
which, following standard nautical engineering practice for balancing
a powerboat, it ran ANTICLOCKWISE, with the starter, cams, timing,
etc all set up to allow that. So it was engine-out again and rebuild
the whole damn thing before Friday.
Bugger! Are you "Fred"? ;-)
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
bra
2018-05-20 18:36:48 UTC
Permalink
'Fred'> > fired it up, put the car in first gear, let out the clutch --- and
Post by ~misfit~
Post by bra
the car lurched BACKWARDS --- it had been the boat's left-side engine
which, following standard nautical engineering practice for balancing
a powerboat, it ran ANTICLOCKWISE, with the starter, cams, timing,
etc all set up to allow that. So it was engine-out again and rebuild
the whole damn thing before Friday.
Bugger! Are you "Fred"? ;-)
No; here's a "portrait" of the real Fred receiving a trophy over 50 years ago:
Loading Image...
Post by ~misfit~
Shaun.
"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
M2T
2018-05-19 11:16:23 UTC
Permalink
Post by ~misfit~
Post by M2T
Post by ~misfit~
Post by bra
Post by ~misfit~
Mmmm shiny tractor engines!!!
Post by bra
When was the last time you looked at a pushrod?
Sonny's pushrods in
this engine are 9/16 inch in diameter.
Hollow I take it? Titanium? Anyway size isn't everything.
No, steel. The impossible chase for total rigidity in a compressed
round-section bar when valve-spring pressures reach 500lbs.
That's crazy! 500lbs valve spring pressures? That's the result of
running a pushrod engine at higher revs than the inherant design is
easilly capable of.
The engine builder is a former drag racer, they rebuild engines
between runs. Wear on cams, valve seats, etc isn't a problem in a
sport where engines are worked on until they explode!
Yeah but as bruce56 said this isn't a drag engine - it's supposedly for
marine use. I don't know about you but I've worked on an inboard engine or
two and they're not fun to lift in and out being in the middle of a boat....
It is a racing engine. I expect they'll be checked regularly. I've been
to one boat race event, not bothered going back.
~misfit~
2018-05-19 12:57:56 UTC
Permalink
Post by M2T
Post by ~misfit~
Post by M2T
Post by ~misfit~
Post by bra
Post by ~misfit~
Mmmm shiny tractor engines!!!
Post by bra
When was the last time you looked at a pushrod?
Sonny's pushrods in
this engine are 9/16 inch in diameter.
Hollow I take it? Titanium? Anyway size isn't everything.
No, steel. The impossible chase for total rigidity in a compressed
round-section bar when valve-spring pressures reach 500lbs.
That's crazy! 500lbs valve spring pressures? That's the result of
running a pushrod engine at higher revs than the inherant design is
easilly capable of.
The engine builder is a former drag racer, they rebuild engines
between runs. Wear on cams, valve seats, etc isn't a problem in a
sport where engines are worked on until they explode!
Yeah but as bruce56 said this isn't a drag engine - it's supposedly
for marine use. I don't know about you but I've worked on an inboard
engine or two and they're not fun to lift in and out being in the
middle of a boat....
It is a racing engine. I expect they'll be checked regularly. I've
been to one boat race event, not bothered going back.
Cheers for that. The only boat racing events I've been to were jet boat
events on a couple of New Zealand rivers (and then only because the
automotive engineering shop I worked in at the time prepared racing jet boat
engines and so we got 'pit passes').
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
M2T
2018-05-19 14:00:02 UTC
Permalink
Post by ~misfit~
Post by M2T
It is a racing engine. I expect they'll be checked regularly. I've
been to one boat race event, not bothered going back.
Cheers for that. The only boat racing events I've been to were jet boat
events on a couple of New Zealand rivers (and then only because the
automotive engineering shop I worked in at the time prepared racing jet boat
engines and so we got 'pit passes').
I've been on a jet boat on the river at Christchurch, NZ. I was bored
shitless after 10 minutes.
~misfit~
2018-05-20 03:21:59 UTC
Permalink
Post by M2T
Post by ~misfit~
Post by M2T
It is a racing engine. I expect they'll be checked regularly. I've
been to one boat race event, not bothered going back.
Cheers for that. The only boat racing events I've been to were jet
boat events on a couple of New Zealand rivers (and then only because
the automotive engineering shop I worked in at the time prepared
racing jet boat engines and so we got 'pit passes').
I've been on a jet boat on the river at Christchurch, NZ. I was bored
shitless after 10 minutes.
There's a world of difference between highly-regulated safe tourist jet
boats and racing boats. The latest fatality in jet boat racing in NZ was
less than 12 months ago. As a New Zealander invented the jet boat it's
always been a popular motorsport here.

These days it's all time trial 'jet sprints' racing around purpose-built
safe courses but not that long ago they raced in stony, mountain rivers
(running along shingle / pebble flood-plains before they get to the sea).
Also these days they limit the main formula to cast iron block and head V8s
with very limited modifications. Nothing like the monsters of yester-year.
Have a look at this if you have 6 minutes to spare
It's a course 20 kms from where I live. We
even have Americans come here to race. ;)
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
M2T
2018-05-20 09:45:37 UTC
Permalink
Post by ~misfit~
Post by M2T
Post by ~misfit~
Post by M2T
It is a racing engine. I expect they'll be checked regularly. I've
been to one boat race event, not bothered going back.
Cheers for that. The only boat racing events I've been to were jet
boat events on a couple of New Zealand rivers (and then only because
the automotive engineering shop I worked in at the time prepared
racing jet boat engines and so we got 'pit passes').
I've been on a jet boat on the river at Christchurch, NZ. I was bored
shitless after 10 minutes.
There's a world of difference between highly-regulated safe tourist jet
boats and racing boats. The latest fatality in jet boat racing in NZ was
less than 12 months ago. As a New Zealander invented the jet boat it's
always been a popular motorsport here.
These days it's all time trial 'jet sprints' racing around purpose-built
safe courses but not that long ago they raced in stony, mountain rivers
(running along shingle / pebble flood-plains before they get to the sea).
Also these days they limit the main formula to cast iron block and head V8s
with very limited modifications. Nothing like the monsters of yester-year.
Have a look at this if you have 6 minutes to spare
http://youtu.be/IkRfpllrEVs It's a course 20 kms from where I live. We
even have Americans come here to race. ;)
I'm familiar with jet boat racing, MotorTV show it nearly every day.
~misfit~
2018-05-20 10:55:29 UTC
Permalink
Post by M2T
Post by ~misfit~
Post by M2T
Post by ~misfit~
Post by M2T
It is a racing engine. I expect they'll be checked regularly. I've
been to one boat race event, not bothered going back.
Cheers for that. The only boat racing events I've been to were jet
boat events on a couple of New Zealand rivers (and then only
because the automotive engineering shop I worked in at the time
prepared racing jet boat engines and so we got 'pit passes').
I've been on a jet boat on the river at Christchurch, NZ. I was
bored shitless after 10 minutes.
There's a world of difference between highly-regulated safe tourist
jet boats and racing boats. The latest fatality in jet boat racing
in NZ was less than 12 months ago. As a New Zealander invented the
jet boat it's always been a popular motorsport here.
These days it's all time trial 'jet sprints' racing around
purpose-built safe courses but not that long ago they raced in
stony, mountain rivers (running along shingle / pebble flood-plains
before they get to the sea). Also these days they limit the main
formula to cast iron block and head V8s with very limited
modifications. Nothing like the monsters of yester-year. Have a look
at this if you have 6 minutes to spare http://youtu.be/IkRfpllrEVs It's
a course 20 kms from where I live. We even have Americans come
here to race. ;)
I'm familiar with jet boat racing, MotorTV show it nearly every day.
Cool.
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
t***@gmail.com
2018-05-21 04:14:17 UTC
Permalink
Cool.
Cool, like you pirating F1 tv coverage,
as a big time F1 fan? Haha
t***@gmail.com
2018-05-21 04:48:10 UTC
Permalink
Post by M2T
I'm familiar with jet boat racing
When you got slapped around at the race,
for being an idiot.
t***@gmail.com
2018-05-21 02:00:29 UTC
Permalink
I was bored shitless after 10 minutes.
Can't contain shit with a damaged asshole.
t***@gmail.com
2018-05-21 04:20:51 UTC
Permalink
I've been to one boat race event, not bothered going back.
Fuck you. Attendance went up the following year.
One less fucking cunt was there.
t***@gmail.com
2018-05-21 04:32:21 UTC
Permalink
I've been to one boat race event
Yes, with busy pride event schedule.
bra
2018-05-24 15:09:38 UTC
Permalink
Post by ~misfit~
Post by bra
No, steel. The impossible chase for total rigidity in a compressed
round-section bar when valve-spring pressures reach 500lbs.
That's crazy! 500lbs valve spring pressures? That's the result of running a
pushrod engine at higher revs than the inherant design is easilly capable
~misfit~ Since you expressed horror at 500lbs valve spring pressure, I thought I would add caffeine by citing the engine of a "Corvette" blown-methanol engine being developed for drag racing. The intake valves are 2.49" diameter -- and the open-valve pressure of 1440 lbs. The rocker arms are built pretty much like the Forth bridge.

http://www.enginelabs.com/engine-tech/engine/top-end-blownz06s-hemi-engine-comes-together-boost/?utm_source=rss&utm_medium=rss&utm_campaign=top-end-blownz06s-hemi-engine-comes-together-boost
~misfit~
2018-05-25 00:56:39 UTC
Permalink
Post by bra
Post by ~misfit~
Post by bra
No, steel. The impossible chase for total rigidity in a compressed
round-section bar when valve-spring pressures reach 500lbs.
That's crazy! 500lbs valve spring pressures? That's the result of
running a pushrod engine at higher revs than the inherant design is
easilly capable
~misfit~ Since you expressed horror at 500lbs valve spring pressure,
I thought I would add caffeine by citing the engine of a "Corvette"
blown-methanol engine being developed for drag racing. The intake
valves are 2.49" diameter -- and the open-valve pressure of 1440 lbs.
The rocker arms are built pretty much like the Forth bridge.
http://www.enginelabs.com/engine-tech/engine/top-end-blownz06s-hemi-engine-comes-together-boost/?utm_source=rss&utm_medium=rss&utm_campaign=top-end-blownz06s-hemi-engine-comes-together-boost
That's insane. Then again, thought I have worked with performance engines
I've not worked with engines that are rebuilt so often. (They said those
springs are good for '50 passes' - less than 5 minutes total on-throttle
running.)

I calculated that, with the 50 psi boost that engine is running there would
be almost 400 lbs of pressure trying to open the valves. That leaves ~1,000
lbs 'closing force'. At 10,000 rpm I'm surprised that the heads don't pop
off the valves!

One thing's for sure - my old valve lifter wouldn't be up to the job of
assembling *that* head. I've built engines with beefed-up valve springs and
concentric valve springs before but nothing like that. To my sensiblities
the demands of drag racing is akin to engine abuse and seems just wrong.
I've only ever built engine desinged to last more than a few minutes
running. <shakes head>

I need therapy now. Looking at some pictures of a desmodromic valve system
will be just the ticket. Off to find some Ducati valve train pics......

Cheers,
--
Shaun.

"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
b***@topmail.co.nz
2018-05-18 09:49:31 UTC
Permalink
Post by bra
When was the last time you looked at a pushrod? Sonny's pushrods in this engine are 9/16 inch in diameter.
Well GM and Chrylser still make pushrod V8s. Although GM have now made a new
variable camshaft V8 for the Cadillac buyers, who think pushrods are for
white trash.
Edmund
2018-05-18 14:43:58 UTC
Permalink
Post by bra
Sonny's Racing Engines is now selling a 13.4-litre CNC-cut billet block V-8 for marine use, that runs all day at 6500 RPM producing 1450bhpon pump petrol.
At 5,000-rpm it gives 1100 lb-ft of torque, so you just know you need this lump in your pickup truck.
http://www.enginelabs.com/news/inside-scoop-sonny-leonards-new-820ci-marine-engine/
When was the last time you looked at a pushrod? Sonny's pushrods in this engine are 9/16 inch in diameter.
Now back to Formula E for those with a delicate constitution :-)
IF, I build this engine in my car, can I make it all the way to
the next fuel station?

Edmund
keithr0
2018-05-19 23:50:39 UTC
Permalink
Post by bra
Sonny's Racing Engines is now selling a 13.4-litre CNC-cut billet block V-8 for marine use, that runs all day at 6500 RPM producing 1450bhpon pump petrol.
At 5,000-rpm it gives 1100 lb-ft of torque, so you just know you need this lump in your pickup truck.
http://www.enginelabs.com/news/inside-scoop-sonny-leonards-new-820ci-marine-engine/
When was the last time you looked at a pushrod? Sonny's pushrods in this engine are 9/16 inch in diameter.
Now back to Formula E for those with a delicate constitution :-)
The book "Beast" by Jade Gurss records the trials and tribulations of
Ilmor building a powerful push rod engine for Penske to race at the Indy
500.
bra
2018-05-20 00:24:33 UTC
Permalink
Post by keithr0
The book "Beast" by Jade Gurss records the trials and tribulations of
Ilmor building a powerful push rod engine for Penske to race at the Indy
500.
Thank you; I did not know there had been a book on it.

I clearly remember the engine appearing, and during Indy qualifying that year, a rueful Mario Andretti said this to a reporter: "Basically, that thing is gonna blow our hats off."

Ilmor "cheated" only in minimizing the inherent problem of pushrods at high rpm: they mounted the camshaft very high in the "vee", so that the rods were very short and thus rigid under high pressure and high revs.

I shall definitely get that book.
Loading...