Old VS New

[Spraguepsycho1]

How would a early 70's OS Max.20 compair performance wise (hp/rpm)to the newer engines, like the OS CVR.15 or even the cheap OS CV.12. I know the newer engines are rated at .56hp for the cheap CV.12 and 1.2hp for the CVR.15, and both these newer engines are rated for up to 36,000 rpm's with peak hp around 31,000. Would a boat designed for a .20 back in the early 70's be noticably faster using a new smaller engine?

 

[nitrotoys]

I have one of the CVR.15s in my truck, and its got good torque and revs.

It likes the rpm. Just found out it really likes 40%

Now they have .18s out,

they have .21s.

I mean if i a boat was made for a .20s motor, hell stuff a .21 in it.

Can always limit the throttle back, with the smaller ones you can only mash the throttle so far.

 

[Spraguepsycho1]

Can always limit the throttle back

lol Surely you jest, too much power is never enough . The reason I was asking this question is I have all 3 of these engines right now, but would need to find a carb for the old .20. If the .12 or .15 will easily outperform the bigger dinosaur engine I will just run those until I can afford a new .21 like the Mac or even just a hot OS buggy engine, since the air coling head would be fully exposed to passing air, but purchasing a new engine won't be possible for me until sometime next summer. I've got the boat almost ready to go now with the .12 engine in it, and weighed it @3 1/2 lbs with no fuel and no exhaust system.

 

[nitrotoys]

I would of said go with the .15 first.

I must of misread, I thought you wanted to know about buying them.

Didnt realize you had them.

let us know how it goes with the .12-.15 in it.

NT

 

[Spraguepsycho1]

Yeah my first instinct was to stuff the stronger .15 in it right away, but I've only had that engine long enough to get it broken in in my truck. lol