Why is it that everywhere I look online that everyone says OHV is outdated?
Honestly it does have it's cons (not the ones you think but usually just valve float, pushrods can actually go up to 13,000rpm if it's built for it) but it being smaller in size and simpler to work on in general kind of outweighs those. It can also be 4 valves per cylinder if the designer so chooses.
Tell me Veeky Forums, what's your opinions on this?
Pic related, a 4.6L DOHC next to a 302 OHV
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here's an example of a 4 valve pushrod aftermarket setup.
(as far as I know Arao was a scam artist and copied this design from an older company)
Ohc is superior in every single application. It's an undeniable fact
> inb4 cherry picked bullshit
Can't do anything like VTEC or other variable valve timing on a pushrod, aka invalidating like half of engine development of the last couple of decades. Oldtech is badtech.
except for size, simplicity and weight distribution.
The only thing that OHC has over OHV is that IF it's directly acting on the valves it eliminates valve-float, and you can get into 20,000rpm in race applications (which is being superseded by pneumatic valves which don't use cams at all)
>inb4 they don't make power per liter compared to DOHC
They can, companies that make OHV don't make them for performance per liter but performance to overall size.
A decent aftermarket head and cam will get you over 100hp/l NA with a stock bottom end.
You can, GM has VVT on some of their pushrod engines already (which is about as good as a SOHC VVT system). If it used two cams in the block (Like GM planned but didn't do) you can get comparable performance to a DOHC VVT system.
And why would I want that?
Pneumatic valves only refers to replacing the valve springs. A engine with pneumatic valves still will be OHC or OHV etc.
> except for size simplicity and weight distribution
A 3l dohc v8 can make 500hp weighing under 300lb
Compared to a 7l v8 making the same power at 500lb and being almost twice the size dimensionally :^)
here's the dual cam system I was talking about.
It can be done it's just never been done because GM make their V8s to be cost effective, this would've added too much cost for them apparently