words by pablo deferrari

Ferrari's Tipo 500 engine
the similarities were too obvious.

there was a time when I immersed myself in Ferrari history and discovered that in the early to mid 50s, they briefly flirted with four-cylinders...that’s when something clicked.
I began seeing a pattern in their short evolution; 2 liters, then 2,5 followed by 3, and finally 3,4. Porsche, too, followed suit with 2, then 2,5 liters evolving into 2,7 before calling it quits at 3.

at first I scoffed and told myself,

“come on, man…you could probably pick any two car manufacturers with a four-cylinder range and see the same pattern.”

but then I dug a bit deeper into Maranello’s reasons for pursuing what seemed an out of character move when you consider their successes with the glorious Columbo V12s and found that my observations had some merit. 

Ferrari 500 F2 (photo by Morten Brunbjerg Bech)
Ascari behind the wheel of Ferrari's first four cylinder race car
torque, efficiency, simplicity, and versatility…these were some of the factors that led both companies down slightly similar paths to create what would become one of their most successful periods in each’s history.  

this is how I got to thinking that maybe, just maybe, Herr Paul Hensler, head of powertrain development at Weissach, took a keen interest in Ferrari’s 4-cylinder engines—and I’m willing to bet that Aurelio Lampredi’s big bore, four-cylinder engine designs for Ferrari played a role in Porsche’s new direction. that’s not to say that he necessarily followed the same formula, but I think he might’ve picked up on something from their trials with big bore engines.

I look at it this way; if Tony Lapine’s fascination with the 1963 Corvair concept penned by Pinin-Farina, the Testudo, might have brushed off on the 928’s design nearly ten years later, one would clearly see how the idea of inspiration from other designs isn’t too far-fetched.

the heart of the 500 F2 displacing 2 liters. (image:http://formula1.ferrari.com/history)
underneath the 500 F2 we see a familiar configuration of front engine and rear transaxle. (image: http://www.arcane-modelisme.com)
so I’m here to suggest such a provocative concept, but I’m going about it in a bit of an open-ended way…I’d like for you make your own assumptions based on some historical facts and comparisons between the two Marques and how they each went about exploring new territory.

now chances were that if you worked at Porsche, specifically in design, engineering, and even the boardrooms…you were a petrol head. so it would be no surprise to have a staff behind the development of these Teutonic cars be influenced by motoring legends whether they be a  neighbor like Mercedes, or Maserati, Alfa-Romeo, Aston-Martin, maybe even a little closer to Porsche’s own blood-line, Auto-Union. it’s when you bring Ferrari into the mix that ears tend to perk up just a tad more as if looking to hear some juicy nasty bits being whispered about a co-worker’s deviant sexual practices involving…let me stop there.

“I don't sell cars; I sell engines. The cars I throw in for free since something has to hold the engines in.” 

Herr Hensler began his career with Porsche in October of 1958 in their design department. he began working on the development of the Porsche Diesel Tractors under chief designer Karl Rabe and in ’63, when Porsche decided to sell off the tractor division, moved over into the passenger car division in the engine testing department; and it was there that he made a name for himself.

his finger prints are all over the design of the flat-6 destined for the new 911, he was the chief engineer on that one. then he began development on the legendary 928 engine before moving on to pioneer the use of turbocharging on gasoline engines making them suitable for street applications by means of a waste gate. Porsche’s water-cooled four-cylinder programme was his next project, and more importantly, the one we’re interested in.  

Herr Paul Hensler (image source: http://www.carzoom.de/newsreader/items/porsche-trauert-um-paul-hensler/)
Porsche's first water-cooled four cylinder engine displacing 2 liters (image: Pgagliardi)
I may be completely off the mark, but stay with me here…

unlike Porsche, who’s philosophy was to race the production cars they sold, Enzo Ferrari’s was to build race cars first, and then create road cars in order to fund his insatiable thirst for racing. he’s been known to say,

“I don't sell cars; I sell engines. The cars I throw in for free since something has to hold the engines in.” 

so when it came time to stir the pot on the racing circuit, Enzo decided to have a chat with Aurelio Lampredi giving him the go-ahead to design a range of four-cylinder starting with  2 and 2,5 liter engines for his sports racers and Formula 1 cars, something Lampredi had been a huge proponent of. you see, he was brought on by Ferrari to do just that, design a new family of engines that would add versatility to the company’s arsenal in racing…Gioacchino Columbo’s V12s ranging from 1,5-3,3 liters, including some of Lampredi’s larger displacement V12s, were all Ferrari had in the beginning of the 50’s.

the advantage in using a four wasn’t necessarily about the horsepower, but the torque. they’d prove to be formidable on the tighter, twistier, and hillier racing circuits using lower revs while bettering their chances for Ferrari domination should the 12-cylinder cars falter in the same race.

cars like the ’51 Ferrari 500 F2, the first one to use a four, with its 2 liter putting out 165hp @ 7000 rpm came in 1st  with Alberto Ascari behind the wheel, 2nd, and 3rd at the 1953 Swiss Grand Prix against Fangio and his Maserati A6SSG, and Hermann Lang in his Maserati A6GCM both packing a 2 liter six. 
1953 Ferrari 553 F2 in action (image: http://www.forum-auto.com)
cross section of the Tipo 500
typical layout of Ferrari's four cylinders.
this is was the the engine that first used the "Testarossa" name because of the red rocker covers....and everyone thought it was the 1984 12-cylinder Testarossa that introduced the name. this one was used in the '56 500 TR and would also be used in the '57 500 TRC that would be the final four-cylinder car Ferrari would make.
the 1953 Ferrari 553 F2 also used a 180hp 2 liter four, along with the 170hp ’53 500 Mondial. the ’56 Ferrari 500 TR, which was the first Ferrari to put the Testa Rossa or “red head,” name on the map with its red rocker covers, and the ’57 Ferrari 500 TRC also had a 2 liter four that produced 190hp @ 7400 revs and 148 lb ft of torque.

then came the 2,5 liter range beginning in 1953 with the Ferrari 625 TF producing 220 hp @ 7000 revs, the ’54 553 F1 and 625 F1 squeezing out 260 hp and 250 hp respectively, and finally, the 260hp 1955 Ferrari 555 F1and 225hp ’56 625 LM brought in the rear of the 2,5 liter gang.

the 3 liter generation, also introduced in 1953, were fitted to only two cars; the ‘53 Ferrari 735 S and the legendary ’54 750 Monza with 250hp and 201 lb ft of torque. then, in 1956, Ferrari introduced its largest ever four cylinder engine with a bore of 102mm and 103mm stroke that displaced a monstrous 3.4 liters developing something like 280hp and 280 lb ft of torque @ 4000 rpm. this was the 860 Monza, and it was as big as they got before Enzo lost interest in cars with four pistons…forever.

as an aside, and in case you were unaware of Ferrari’s numerological naming of its cars, I’ll tell you…all of the numbers, save for the ’53 553 F2 , ’54 553 F1, and ’55 555 F1, represented the single cylinder unitary cubic capacity.

so it’s clear to see Ferrari’s evolution of their four-cylinder engines from a relatively small 2-liter all the up to the 3.4-liter monster that saw an end to this wonderful line of power plants few know about, simply because Ferrari will always be better known for the potent 12-cylinder engines…much like Porsche conjuring up images of the 911 when spoken about.
1953 Ferrari 500 Mondial (image: Chris Hunkeler)
the legendary 1956 Ferrari 500 TR, the first Testarossa.
the reason why the TR was named, the famous "red head."
the final 2 liter Ferrari, the 1957 500 TRC...this would also be the last year for their four cylinder range (image: Rémi)
the svelte 924 would have its 2 liter until 1985. (image: Alf van Beem)
it’d be too simple to say,

“ok, Porsche and Ferrari had the same size fours…so what?”

I’m not after that sort of comparison…and you’re not getting off that easy. I want you to look at a few things that led me to believe that Maranello, namely Lampredi, was onto something that Stuttgart, namely Herr Hensler, picked up on.

first…the reasoning behind both company’s decision on using four cylinders.

we already know that Ferrari wanted a smaller engine that made the cars not only lighter and more agile than the competition, but had more grunt at lower revs than the higher strung twelve and six cylinder cars they and the competitors were using. Enzo was in it for the constructor’s title; he figured he’d have all the bases covered by entering two to three different engine configurations in a series of races to better his chances.

"by Dr. Fuhrmann racing it later proved another matter, Porsche could still pose a serious threat with a four cylinder engine..."

Porsche, on the other hand, didn’t have a four so they borrowed VW’s chiefly because the 924 was supposed to be a VW…and as we all know, they bought the design back from Volkswagenwerke so it made financial sense to use the newly developed Audi 100 engine that would also be used in the VW LT van. it benefitted them economically both to sell as their entry level model replacing the 914, and to produce; we can’t forget about the energy crisis that was going on at the time, the formula was perfect. 

by Dr. Fuhrmann racing it later proved another matter, Porsche could still pose a serious threat with a four cylinder engine proving it to be worthy of consideration for further development. and, like Ferrari, they had another weapon in their arsenal expanding their versatility both in competition and the market.

this drops me neatly into the next subject, evolution…the one uncanny similarity.
cross section of the 924's 2 liter (image: http://www.porsche924-944.nl/)
the addition of a turbo took the 2 liter to loftier heights in performance. (image: http://www.porsche924-944.nl/)
evolution, the Porsche way. (image: http://www.porsche924-944.nl/)
although Porsche left the 924's lump at 2 liters, it would undergo an evolution from this potent 924 Turbo...(image: Mark Harkin)
to this fire-breathing 320bhp 924 GTR. (image: The359)
now both Ferrari and Porsche used 2 liter capacities for different reasons. Ferrari used it on the 1951 500 F2 in order to compete in Formula 2 which had an engine size restriction set at 2 liters while Porsche used the Audi unit in the 924 for reasons already mentioned.

but this capacity would prove itself in the long term as it was used by both for several years. Ferrari began and ended their four cylinder run from ’51 until ’57 with this size while Porsche ran with it from 1975 until 1985. and while Ferrari fiddled with compression ratios, carburetors, and two different bore and stroke configurations, the 924’s normally aspirated mill remained unchanged with the exception of Turbocharging and a brief stint with Methanol fuel necessitating slight modifications.

a little something worth mentioning here was the actual displacement…nearly identical at 1,984cc save for the Ferrari 553 F2 which had a 1,997cc capacity. because Ferrari’s goal was strictly racing, a larger bore of 90mm and shorter stroke of 78mm (for the 1,984cc engine) was needed to extract the necessary horsepower for speed whereas the 924, with a more square bore and stroke of 86.5mm x 84.4mm made the engine more tractable for everyday driving with 125bhp and 121 lb-ft of torque.

then came the 2,5 liter generation. 
1953 Ferrari 625 TF (image: http://www.ferraridatabase.com)
the TF's 2,5 liter engine sporting twin Weber 50DCOA3 carbs. (image: http://www.ferraridatabase.com)
the 2,5 liter 1954 Ferrari 553 F1 (image: Anonimo)
the 260bhp 1954 Ferrari 555 F1 (image: http://todosobreferrari.blogspot.com)
this 1954 Ferrari 625 F1 gave the performance that the 553 F1 lacked. (image: John Chapman)
the 1956 Ferrari LM, the last if the 2,5 liter cars. (image: http://forumducavallino.nuxit.net)
Professor Helmuth Bott took a shine to the 924 Turbo engine fitted with the experimental twin contra-rotating balance shafts. it was clear to him that this was the direction Porsche should pursue especially with the higher capacities they had planned along its evolution. 

before this decision was made, however, Porsche looked into six and eight cylinder configurations going so far as making a prototype with the PRV Euro V6 engine engineered by a consortium of Peugeot, Renault, and Volvo engineers (see our article here about this engine), but no one liked it…too coarse and heavy offering little in terms of horsepower were the main beefs.

they even built a 3.4 liter V6 prototype which was essentially the V8 with two cylinders chopped thst looked promising and ran smoothly, but was too big for the 924/944 engine compartment, too expensive to build, and a bit too powerful for this type of chassis; it also weighed nearly 55lbs. more than the 924’s lump. in the end, they agreed that utilizing half of the 5 liter 928’s engine would be the way to go about things, especially from an economic standpoint where parts and tooling would be common.
the 1982 Porsche 944 finally had an engine completely designed by Porsche...the 2,5 liter weighed the same as the 924's 2 liter but cost more to manufacture. (image: Damameri)
the 2,5 liter would also go through a period of evolution. (image: http://www.seriouswheels.com)
Ferrari’s foray into 2,5 liters began with the 553 F1, again, for the sole purpose of meeting 1954 Formula 1 engine capacity limitations set at that size. Porsche’s? they desperately needed to convince their market that they could produce an entry level Porsche further removed from VW’s apron strings packed with more of their own DNA…read marketing.

three very interesting facts come to light when comparing the Ferrari 553 engine with Porsche’s 944/924S. first, they shared identical 100mm bores but Ferrari utilized a 79,5mm stroke nudging its displacement to 2497.56cc against the 2,479cc capacity of Zuffenhausen’s lump by means of a 78.9mm stroke.

second,  Porsche went with using balance shafts to minimize the NVH (Noise, Vibration, and Harshness) quotient prudently necessary on road cars displacing more than two liters…Ferrari went without them, even when they went to 3,4 liters. apparently, rotating masses of the second order was something they weren’t too concerned about especially since these engines weren’t made to last hundreds of thousands of miles.

and third? Lampredi designed the head and cylinder block as one casting to eliminate head gasket issues while Porsche went the tradition route with separate head and block but unlike Ferrari, didn’t use cylinder liners. they cast their blocks in Reynolds 390 aluminum and etched the bores to expose the silicon particles that the piston rings glided on…a process Porsche referred to as Alusil.
Porsche's 2,5 liter would evolve into a Turbocharged version from 220bph to 250bhp. (image: Detectandpreserve)
the Typ M44/51 Turbo (image: http://www.914world.com/bbs2/uploads/post-73-1406335085.jpg)
and a 16-valve 944S. (image: Alexandre Prévot)
the Typ M44/40 16-valve engine. (image: http://gallery.rennlist.com/albums/albuq78/944S_engine_painted.jpg)
the complexity of combining the 16-valve head with Turbocharging didn't make much sense for production according to Hensler, but the exception was made for this 420hp beast for the '81 Le Mans race. (image Detectandpreserve)
the potential of Porsche's four cylinder programme was underscored by this engine in the 924 GTP (aka the 944 prototype). (image: Dan Beckett)
the 1989 Porsche 944 2,7 used the block that would be introduced in 944 S2 and 968.
compression ratios and induction paired with racing sensibilities also meant that Maranello could afford to have their engines put out impressive horsepower figures ranging from 220 to 260 (numbers Porsche would reach with Turbocharging), against the 8-valve 944’s conservative 163bhp…but keep one thing in mind, Ferrari’s engines were normally aspirated and were products of mid 1950’s technology.

aside from Turbo charging, Porsche’s 2,5 would go on to use 16-valves and twin cams while Ferrari would stick with 8-valves while using the signature Italian twin cam set-up coupled with twin spark plugs.

at this point, I’m sure you already see a pattern developing…but we’ve still one more engine to discuss—the 3 liter.

1954 Ferrari 750 Monza

the 3 liter 1953 Ferrari 735S
Typ M44/43 3 liter engine with Variocam producing 240bhp DIN...the torque monster that gave its 911 contemporary a run for its money. (image: http://www.moibibiki.com/Porsche%20968.html)

1994 Porsche 968 CS

1991 Porsche 944 S2 with the first evolution of the largest displacement Porsche would use in their four-cylinder line, 3 liters.
this would be Porsche’s last increase in displacement, and the end of the four cylinder’s evolution…but not without a stopover at 2,7 liters. interestingly, the 2,7 was only offered for MY 1989 closing out the 8-valve era using the same 78.9mm stroke as the 2,5, but packing a 104mm bore and larger valves. this would be the same block used for the 944 S2 and 968 but in order to increase the displacement to 3 liters, they dropped in a crankshaft that would increase the stroke to 88mm.

the 2,7 is the joker in this article since Ferrari never used this size in their four cylinder family. what Lampredi did was design a 3 liter for the Ferrari 735 S and 750 Monza instead. the reason that Enzo decided to increase displacement from 2,5 liters was a logistical one. you see, he was so happy with the successes of the four cylinder cars in Formula 1 and 2 that he decided to put this to the test with closed-wheeled race cars…the 625 TF with 2,5 liters was the first in that category beginning in 1953 at Monza.

the problem was that the little two and half liter motor was really designed for medium-fast circuits, and because the legendary Monza circuit had more indeterminable straights, the TF’s 220hp and 240km/h top speed didn’t enable it to do its best there; this is why they upped the ante with 3 liters in the 735 S. its more svelte, open cock-pit body designed by Carrozzeria Autodromo di Modena coupled with 5 more horsepower and a top speed of 260km/h made it a serious threat at Monza in 1953 where it was in the lead from the beginning of the race until it collided with another Ferrari, a 250 MM, it was about to lap. the following year at Monza, Ferrari would unleash the 750 to finish the job by coming in first. this monster displaced 2,999.62ccs, up from the 735 S’ 2941.66cc, and would be called the 750 Monza to commemorate its win in 1954 at that circuit.

but let’s get back to the 2,7. in 1988, Porsche decided that it needed a thorough revision of their four cylinder line. the 924S was going out of production, and so was the normally aspirated 2,5 liter 944. so what they did was offer this normally aspirated 2,7 liter 944 as a one year only car in 1989 that had a bit more horsepower, exactly 2 more, bringing it up to 165bhp, but more torque at 166 lb-ft and a higher 10.9:1 compression ratio. nothing too radical which was precisely what they had to change, and they did with the series 2 944.
1955 Ferrari 857S was the first to have the new 3,4 liter monster engine designed to hold off the strong Meredes-Benz opposition. (image: http://smallglassplanet.blogspot.com)
the 3,4 liter engine that lived in the 857S...do you see any balance shafts? (image: http://whataboutcars.com)
the largest Ferrari would ever take four cylinders...the 1956 860 Monza. (image: http://www.wallpaperup.com)
the opus of Porsche's four cylinder ended with this 968 Turbo RS with 350bhp...only 14 were made. (image: http://www.freisinger-motorsport.de)
you see, the 944 was getting a bit long in the tooth and sales numbers being reported by dealerships reflected this. the only logical choice was to give the 944 chassis one more go with a more powerful engine using the 2,7 liter block they already had as the foundation and increase its capacity to 3 liters while letting it breathe through 16-valves. they’d also introduce a Cabriolet version into the mix to bring back some excitement to the aging four cylinder models and give yuppies who couldn’t quite afford a 911 something as glamorous at a lower price.

and much like Ferrari did with their own 3 liter programme, having two variants with different carbs, compression and bores, Porsche too evolved theirs. but instead of having two different 3 liter blocks, they simply added VarioCam to with the introduction of the 968 taking their four-cylinder opus from 211bhp in the S2 to a healthy 240bhp in the 968.

Jochen Freund, father of the 968 development, mentioned that there was the intention to take the 3 liter four to 3,2 or even 3,4 liters…but there were no plans set to do so. the saga of Porsche’s four cylinder water-cooled engine came to an end at 3 liters.

Ferrari, not having the pressures of marketing and selling a reliable product, chose to punch out their four to 3,4 liters by using 102mm bores and 105mm stroke in their final version of the big bore with the 857S and 860 Monza. after that, they moved on and began developing the legendary V6 that would honor Enzo’s son Dino’s name.

the success Ferrari had with four cylinders quite possibly mapped out Porsche’s own development of their big bore fours. this piece of history may have proved to be very valuable to men like Herr Hensler or even Dr. Fuhrmann, who might’ve recognized this and gained knowledge from it.

say what you will about Italian engineering. although they haven’t mastered technologies in plastics and electrical bits, their mechanical knowledge and ingenuity rivals that of the Germans. who do you think was the first to implement Variable Valve Timing in a production car that Honda’s VTEC and Porsche’s VarioCam would later improve on? yep…they can thank Alfa-Romeo for that one—they did it in 1980.


editor's note: curious about how they sound compared to our fours? check out the videos below...


Matt Mariani
09/03/2014 21:44

Wow, my head hurts. Must re read this tomorrow when less tired.

call me Pablo i miss you

dr bob
10/24/2014 19:09

The discussion of the 50's four-cyclinder Ferrari engines brings back a few memories. A friend brought one of those cyclinder head/sleeve assemblies by with the need to regrind the valve seats and fit up new valves. As you can deduce from the cross-section drawings, fitting new guides and seats was far from what might be an easy operation on a "conventional" engine with removable head. There was a week of building fixtures just to draw the guides in and fit new seats. Then very shallow stones on pilots from the spring side to finish the seats. Then hand-lapping the valves in. Everything was reach-up-inside the bores which of course couldn't be scratched. I wasn't smart enough to take pictures. I was in my early 20's, about the same age as the car.

03/08/2015 16:26

Wonderful research that I would like to hotlink to my own Facebook page, Looking Back Racing. Please visit there and let me know if that is to your approval!

el jefe
03/08/2015 19:15

@onaroll—hotlink away my friend, we'd be more than happy to share it with your project!


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