I translated the final conclusion of the five cylinder study:
The conclusion is that a five cylinder engine needs a torsional vibration damper per say.... My Volvo (VW 2.5 TDI) indeed has a crankshaft torsional damper... John Deere 6 cylinder engines have torsional dampers...
...In fact, 90% of todays automotive diesels have torsional vibration dampers, because of torsional vibrations caused by the multiple injections per cylinder of todays Euro 5 diesels.. ZF even wants a torsional vibration analysis on their Ergopower transmissions for TIER 3 and higher engines, because thats where drivetrain resonance issues surfaced... Even the Paus small wheel loader had a cab resonance issue, after a common rail TIER 3 engine was fitted, even though it ran smoother at idle than the previous mechanical engine...
The author is sceptical: He says: I am not an economist but i wonder if it makes sense to construct a five cylinder (that needs the added expense of a torsional vibration damper) if you can derate a six cylinder ?
....That was a very valid point in the 80s and 90s, and the reason the 5 cylinder disappeared and was replaced by the turbo 4, in the Fiat 880-5, Same Leopard, the Deutz DX85 and DX90, and the Deutz inline 5 in the Eder/Caterpillar excavator.
But then: What makes more sense for Zetor, add a 5th cylinder unit to an existing design to gain 25% displacement and adding a torsional vibration damper a Common Rail engine would need anyway, or change the entire production line to increase the swept volume of the 4 cylinder by 15% ??
Deutz introduced a 5 liter 4 cylinder lately, next to their 4.1 liter 4, and 6.1 liter six... Because with all the emissions stuff, engines need to put out sufficently hot exhaust gases, even when too small engines in heavy applications dont last, or cant provide the transient response...
The turbo 4 replaced the naturally aspirated 90-100hp 5 cylinder in the tractor, while in automotive, the 5 cylinder engine became popular especially at the end of the 80s, early 90s. Fiat Marea, Volvo 850, VW Transporter, Mercedes E250, Mercedes Sprinter, all used inline 5 engines. Even in America, Chevy sells an inline 5.
If Zetor wants to compete in he 4.5 to 5 liter displacement, 150-170hp, against the Agco 4.9 and the Deutz TCD 5.0, and JD 4.5 and New Holland 4.5, i would still prefer to add another cylinder and offer something with character, for lowest development cost than to add a 4.7 liter 4 cylinder that needs a lot of development due to the different combustion chamber shape...
The Volvo 850 was nicknamed "the rumble" for its distinguished engine sound...
Also, hear this heavily tuned Mercedes OM 605 (2.5 liter inline 5, pre-chamber mechanically injected) roar...
[MEDIA=youtube]MiNAGeTn4x4[/MEDIA]
Or more practical, a Sprinter with an OM 605 at 300hp 
[MEDIA=youtube]ybB-jtyILCo[/MEDIA]
And here a direct injected row 5 diesel:
[MEDIA=youtube]jvnFAeYTax8[/MEDIA]
And here Volvo 850 "the rumble" (even though the rumble changes into a growl at racing rpm )
[MEDIA=youtube]3HZCHLIrxSw[/MEDIA]
Then to the offroad engines, here a Fiat 880/5
[MEDIA=youtube]gM9NQQTHftc[/MEDIA]
And here a Deutz DX90 F5L912
[URL unfurl="true"]https://www.youtube.com/watch?v=KABq5HcMIqI[/URL]
And a Same Leopard 95: With not too much silencing, it does sound a bit like the Mercedes OM605 and the VW TDI at low rpm
[URL unfurl="true"]https://www.youtube.com/watch?v=xq2Ot2xXBbs[/URL]
And a Tiger 100, with the same 105x120mm bore and stroke as the Zetor engine:
[URL unfurl="true"]https://www.youtube.com/watch?v=72SrS9whPJc[/URL]
...A 5 cylinder doesnt sound as cheap as a 4 cylinder... People are suspicious about the 170hp four cylinders... And manufacturers have to offer both a 4 and a 6 cylinder model to statisfy either group of buyers, and homologate an engine and exhaust aftertreatment set twice in the 130-170hp class...
I would simply replace both the Forterra HD and the Crystal by a 5 cylinder tractor of 140-155-170hp and sell only three models within one homologation in this power range, instead of five models in 2 homologations...
Lets face it: Zetor is left with an odd customer base. They will like it anyway, as long as it is a genuine Zetor engine. Maybe some potential customers (that now use different brands) will dislike the unique engine, (maybe 5%) but most will embrace the brand even stronger when its a little different
