Mk17 vs Mk17 EVO

[ScubaBros]

I know alot of people here like to bash manufacturers for trying to make money. Buuut with that being said...

The "evo" is thought to be an evolution of SP reg models for the mk2 mk25 and mk 17.

Cosmetic changes aside cold water performance was vastly improved on the piston 1st stages mk2 and mk25.

The mk 17 was already outstanding in cold water but on the evo model of the mk17 while internal parts remain for the most part unchanged, body machining and sizing are vastly different. Esentially metal encasing the internal high pressure seat chamber is thicker making it better in the cold water. Or at least thats the idea behind it.

No need to rush out and get one if you already own an older version. But the mk17 evo is an excellent regulator.

Hate SP all you want. But this reg is awesome. And the parts kit is reverse compatible with the older mk17 so support for the regs will be around for quite some time. Just like current mk2 kits are reverse compatible for all mk 2s back to the 60s.

Happy diving everyone!

 

[DA Aquamaster]

Let me start with saying that the fully sealed Mk 17 was already bullet proof in cold water.

I switched to them as soon as they came out because the Mk 25 TIS first stages sucked in 35 degrees F water and basically required very good cold water technique to avoid a freeze flow.

On one of my first dives with a Mk 17, I decided to see what it could do. I pre breathed it on the surface to get it good and cold before it event the water, I dive bombed to 100' and once there did long simultaneous blasts on both dry suit and wing inflators while breathing, and had zero problems despite 35 degree water. A Mk 25 would have been free flowing in the same conditions where basically all the rules of cold water reg technique were violated.

I then deployed a 200 pound lift bag, secured it to a wreck and filled it in one continuous blast. I had a ball of ice on the first stage, but it didn't freeze flow.

So...is the Mk 17 EVO more freeze resistant? No. The Mk 17 was already bullet proof in cold water.

Having thicker brass around the seat doesn't mean anything - it will still cold soak and once it's below freezing, it's below freezing. What matters is heat transfer to help transfer heat from the water to the regulator, and keeping water out of any places where it freezing would cause the reg to freeze flow.

The reason the brass is thicker is that all the LP ports are now "high flow" ports.

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The major differences on the Mk 17 EVO are:

1) the HP ports are now in the same plane as the LP ports so they all come straight off at the same angle; and

2) all of the LP ports are now "high flow" ports.

The new port arrangement is a mixed blessing as I like the old Mk 17 configuration better for side mount diving.

Does having all 4 LP ports be high flow ports mean anything special? No. The two 'regular' LP ports on the Mk 17 flowed plenty of gas already, so the slightly higher flow from the 2 "high flow" LP ports was just overkill and marketing hype.

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Scubapro departed from a long standing policy of making any engineering changes backward compatible when they decided that the swivel cap on the Mk 25 EVO needed different threads. This means that while you could update the earliest Mk 25 to the current Mk 25 standard, you now can't update even the most recent Mk 25 to the new EVO standard. That's selling out engineering and customer service in favor of designed obsolescence and forcing more sales for the many Mk 25 divers who are still not impressed with the cold water performance of the latest iteration of the Mk 25 TIS. Is the Mk 25 EVO actually any better in cold water? Maybe. I have no idea of ever buying one to find out as even if it's better, it still won't be up to the same cold water performance standard as the Mk 17.

 

[ScubaBros]

Duh... noone said the mk25 evo was better than a 17 or 17 evo in cold water... and noone said the 17 wasnt a perfect reg already for cold water.

The 17 evo is a new version of a 17. Big deal. Its a redesign so live with it. It is improved. If you dont think its a big deal don't buy one.

 

[ScubaBros]

And saying that body parts on sp regs are reverse compatible is dumb. Thats like saying a mk5 swivel should fit a mk10 body. They are different regs.

A 1973 mustang hood doesn't fit a 2017.

Be realistic.

 

[ChristophScuba]

Haters gonna hate.

 

[DA Aquamaster]

Duh... noone said the mk25 evo was better than a 17 or 17 evo in cold water... and noone said the 17 wasn't a perfect reg already for cold water.

The 17 evo is a new version of a 17. Big deal. Its a redesign so live with it. It is improved. If you dont think its a big deal don't buy one.

I'm glad we agree the Mk 25 won't hold a candle to the Mk 17 in cold water, and that the "improvements" in the Mk 17 are cosmetic.

And yes, if I acquire any more Mk 17s they'll be the pre EVO model as I prefer the hose routing.

 

[KlixTrio]

Let me start with saying that the fully sealed Mk 17 was already bullet proof in cold water.

Thanks for the awesome answer. I decided to go with the EVO because its newer, better hose routing and just "shinier". I'm surprised you said the Mk25 would freeflow, at my LDS I asked them what regs they rent out for ice diving. They told me they use the regular regs (not cold water or sealed) because they dont stay down long. Happy I bought my own

 

[DA Aquamaster]

And saying that body parts on sp regs are reverse compatible is dumb. Thats like saying a mk5 swivel should fit a mk10 body. They are different regs.

A 1973 mustang hood doesn't fit a 2017.

Be realistic.

No, it's not like saying a Mk 5 swivel should fit a Mk 10 body. They are completely different designs. Given the differences in piston diameters and the fact that the piston head rides in the body in the Mk 10 and in the swivel cap in the Mk 5, no one would expect the swivel turrets to interchange although the turrets do interchange within the first stage families (Mk 1 Mk 5, and Mk 8, and Mk 9 and Mk 10). Besides the example you give would be forward compatible not back ward compatible.

Your Mustang example also sucks as well as the '73 and '17 Mustangs share a name, but are not in any way shape or form the same cars and have zero parts commonality.

Remember the Mustang II (1974-78)? Sucky cars. The third generation Mustangs (1979-1993) were not much better. The fourth generation Mustangs (1994-2004) started to look a little like Mustangs again. The current Mustangs are 6th generation Mustangs and share absolutely nothing with the original design - not even the basics like rear suspension design.

I'd pay more for a low milage Telstar re-manufactured 1967 Mustang than I would for a 2017 Mustang with all the options.

 

[DA Aquamaster]

Thanks for the awesome answer. I decided to go with the EVO because its newer, better house routing and just "shinier". I'm surprised you said the Mk25 would freeflow, at my LDS I asked them what regs they rent out for ice diving. They told me they use the regular regs (not cold water or sealed) because they dont stay down long. Happy I bought my own

I suppose if your first stage freezes it gives you an excuse to end the dive. Traditional ice diving on a tether is really pretty boring and it's analogous to swimming around a fish bowl. After a couple laps you're ready to be done.

My preference for ice dives was to use cave penetration techniques - using a primary and secondary tie off and then running a line. That allowed me to swim several hundred feet from the hole, based on thirds or fourths gas planning - but it's also where you wanted both redundant doubles and reliable cold water regulators.

If I'm going to do a single tank ice dive, I use a double hose regulator as both the first and second stages are sealed, making both stages bullet proof in cold water.

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Scubapro is a piston regulator company and they only make diaphragm regs under duress as their dealers have customers who want piston regs.

As such they are philosophically unable to say that the Mk 25 sucks in cold water, or that a diaphragm design could possibility be superior to a piston design. They'll keep saying that until all the old leadership dies off.

Back before the Mk 17 was around we sold a lot of Mk 2s to public safety dive teams because they were much more reliable for ice diving than the Mk 25 TIS.

That changed when the sealed Mk 17 came along as it was ideal for both ice diving and contaminated or just plain dirty water diving.

 

[Couv]

And saying that body parts on sp regs are reverse compatible is dumb.

Why? Especially when one is talking about the same model. As DA pointed out, for years SP had a policy of engineering upgrades so that the older models could be upgraded with the newer parts. The 109 could be upgraded to the Balanced Adjustable. The Balanced adjustable could be upgraded to accept the new s-wing poppet. The MK 20 went through a series of piston changes. These are all advantages to the consumer.

So tell me, what do you consider the advantage to the consumer in having the EVO's upgrades incompatible with the older models?