20 replies to this topic

[quintin cloud]

Hi All

I light of the thread of cutaway pictures, I am busy researching engines for a project that I am busy working on, now days the most common engine config. is the OHC (overhead cam), what engines and namely engines been around the V8, V12 or V16 engines made use of the OHV config. I know that the Ford kent engine is a OHV engine as my has one in his Lotus 7 Rep.

Thanks

[2F-001]

One recent example would be the Ilmor "500i" engine used (to some effect) at the '94 Indianapolis 500.

For other obvious examples, think of some Ford and Chevrolet V8s used in '60s sports-racing cars; or F5000 and CanAm

Edited by 2F-001, 08 June 2011 - 07:10.

[Lee Nicolle]

The Mercedes pushrod OHV engine that won Indy in the 90s. A Penske car.

[Catalina Park]

Just to be picky but OHC engines have OHV.

[GMACKIE]

OK then, if you want to get picky, what about 'boxer' engines [Porsche, VW. Subaru, etc.].......Are they side-valve?

[Allan Lupton]

OK then, if you want to get picky, what about 'boxer' engines [Porsche, VW. Subaru, etc.].......Are they side-valve?

Yes, quite, and the Subaru engines should be described as single o.h.c. or twin-o.h.c. even though the former has a camshaft on each block and the latter has two on each block and the camshafts are next to the cylinders (or above and below).
I didn't quite understand the original question, but I think it is fair to suggest that every conventional valve arrangement (side, IoE, overhead inline and overhead inclined) has been used on every conventional cylinder arrangement (inline, V and horizontally opposed) and pretty well every number of cylinders (well 2, 4, 5, 6, 8, 10, 12 and 16), and where overhead valves have been used with overhead camshafts again single and double have been used on every layout.

[D-Type]

Alan, you forgot 3-cylinder (DKW, Saab, Wartburg, Trabant) and 5-cylinder (Audi)

Add in 2 valves per cylinder and 4 valves per cylinder together with which are inlet and which are exhaust . Then there's the alternatives to poppet valves - sleeve valves, cuff valves, reed valves (whatever they are). Add valve action: desmodronic [sp?], coil springs, leaf springs, pneumatic.

The permutations are endless.

[Macca]

Reed-valves are used on 2-strokes between the carburettors and inlet (which goes into the crankcase) to stop the mixture blowing back - as the name suggests, they are generally a pair of springy metal or GRP petals set in a block pointing downstream which open when the induction stroke is sucking and are pushed closed by reverse pressure.

See here.

Paul M

[Ray Bell]

And they certainly aren't overhead...

The Daihatsu range in the eighties included a 3-cylinder OHC engine, however.

[David Birchall]

I think it would be easier to name the engines that were NOT pushrod OHV say more than 30 years ago!

[Allan Lupton]

Alan, you forgot 3-cylinder (DKW, Saab, Wartburg, Trabant) and 5-cylinder (Audi)

Add in 2 valves per cylinder and 4 valves per cylinder together with which are inlet and which are exhaust . Then there's the alternatives to poppet valves - sleeve valves, cuff valves, reed valves (whatever they are). Add valve action: desmodronic [sp?], coil springs, leaf springs, pneumatic.

The permutations are endless.

He did ask about valves so as all the three-cylinder engines you list are two-stroke they haven't any. Daihatsu and GM-Opel/Vauxhall seem to have 3-cylinder four-strokes.
Oh and I did include 5-cylinder.
The non-poppet types of valve were all pretty uncommon apart from Knight double-sleeve and Burt-McCollum single-sleeve between about 1915 and 1935 - and the latter were much used in aeroplane engines until the gas turbine took over in about 1950.

[Bob Riebe]

Hi All

I light of the thread of cutaway pictures, I am busy researching engines for a project that I am busy working on, now days the most common engine config. is the OHC (overhead cam), what engines and namely engines been around the V8, V12 or V16 engines made use of the OHV config. I know that the Ford kent engine is a OHV engine as my has one in his Lotus 7 Rep.

Thanks

You probably should call it Push-rod or cam-in-block OHV engines.

[kayemod]

He did ask about valves so as all the three-cylinder engines you list are two-stroke they haven't any.

Strange that no-one has mentioned what's probably the one produced in greatest numbers, the three cylinder four-stroke that VAG used in the Polo some years ago. My wife used to have one, surprisingly smooth and remarkably torquey.

[Paul Parker]

Strange that no-one has mentioned what's probably the one produced in greatest numbers, the three cylinder four-stroke that VAG used in the Polo some years ago. My wife used to have one, surprisingly smooth and remarkably torquey.

The two I drove were gutless, rough running and quickly became known as the lawnmower as in I'll use the lawnmower for the shopping dear.

[kayemod]

The two I drove were gutless, rough running and quickly became known as the lawnmower as in I'll use the lawnmower for the shopping dear.

No honestly, ours was perfectly OK, better in almost every respect than the 4 cylinder Citroën she has now, but was yours the 55 or 65hp version?

[thatguy0101]

I think it would be easier to name the engines that were NOT pushrod OHV say more than 30 years ago!

Sidevalve engines were pretty common in the States til the early 50s. Chrysler, Studebaker, Willys, and AMC/Rambler built sidevalve sixes til 1960 or later.

[Alexey Rogachev]

I may be wrong but it seems to me that SV and OHV are quite different valve schemes

[Lee Nicolle]

Really most engines used in the last 50 plus years in most forms of racing have been ohv, in all continents. Sidevalve Ford V8s would be the biggest exception. A lot of Euro engines were OHC [and OHV] far earlier than American engines. Though the very American Offenhouser engine was OHC a very long time ago.
Very popular OHV engines have been [and still often are] small block Chev, All forms of pushrod small Ford engines, BMC A series engine, Ford Windsor engine and many more, most which have been used since the 50s or early 60s

[Ray Bell]

What he's saying, Alexey, is that there still were some side-valvers around quite late in automotive history, whereas David Birchall had said it was hard to find an engine that wasn't overhead-valve in that era...

Both are correct, of course. There were far, far more ohv designs in production in the fifties and sixties than side-valves.

[Paul Parker]

No honestly, ours was perfectly OK, better in almost every respect than the 4 cylinder Citroën she has now, but was yours the 55 or 65hp version?

If I recall correctly it was 23.5 hp version with cable brakes.

[Bob Riebe]

Sidevalve engines were pretty common in the States til the early 50s. Chrysler, Studebaker, Willys, and AMC/Rambler built sidevalve sixes til 1960 or later.

The last U.S. company, that I know of, to use a side-valve engine in competition, were the 1969 Harley Davidson competition bikes.