3W85- Classic or the CS series

[luv2flyguy]

I"m buying a 3W85, is the CS series really worth the extra money, which is about a $100.00 difference? I've only owned one 3W and it was the AI blue head series and it made great power.

[Flyinhigh]

My CS 150 ran (and still does) like a sewing machine from day one. Noticably more power, lower idle, and smoother transition than my classic. The higher compression, lighter and better matched components make a difference. They do take a little longer to break-in to reach optimal power-band, but are well worth it for the extended lifespan. My $.02: Spring for the CS version. You'll be glad you did and your bro's will be impressed with you tuning abilities

[luv2flyguy]

Thanks Flyinhigh for the reply, I especially just like to color of the heads on those CS engines, they just look bad to the bone!!! May get mine at AI however just because it's so much closer. The shipping to me is only 2 days ground vs. 5 to 6 from AZ. Hope that makes sense.

[Flyinhigh]

I don't think it makes a huge difference, but the painted finish, however higher the 'cool-factor', does build-up heat a little more. My "sleeper" CS 150 was special-ordered from Cactus Aviation with unpainted heads. I love to let people assume the smooth-running engine is due to my talented tuning abilities. I'm actually still flying on factory needle settings and maintain a running temp of 190 degrees f. My classic 150 after 7 gallons of break-in would turn my PT 32X10 with respectable authority. My CS 150 rips the snot out of the same prop at less than full throttle and is only on its third gallon. That higher compression makes a big difference in power.

Make the plungs and don't look back ........ even if you do get the flashy paint finish. The heat on single cylinders isn't as big a factor. Just don't lean in on the needles too quick. Let that baby break-in slowly (mine will want 7 gallons of 32:1, and 7 more of 40:1 natural before I go synthetic and even think about touching the needles).

Mine from Cactus got to me in two days. How is Oregon closer to NC than Arizona?

[luv2flyguy]

Aircraft International is in NJ, that was what I was refering to about the 2 days. From NJ to NC is only 2 days as I have gotten something from them before (acceseories). Anyway I'll let you know what happens and thanks again.

[Flyinhigh]

Oh. I think I got AI confused with Chief Aircraft. My bad. I've been under the wrong impression for some time now. Thanks!

[notorious_benny]

The painted fins only read higher temps than unpainted fins (when using an IR temp gun) due to the different emmisitivity figures of silver to a darker colour.

If you paint a block dot of nail polish or similar on your unpainted fin then shoot it with your IR gun you will get a higher reading, dosnt mean the actual internals are any hotter...........

[Bunky F. Knuckle]

Spring for the CS. I still debating on selling both my 100 and 106 and buying a CS 106!!!! The 85 looks like a HORSE of a engine!!!!!!!!!

3W livin up the the "POWER MEISTER" motto!!!!!!!!!

[Flyinhigh]

	Quote: Originally Posted by notorious_benny
	The painted fins only read higher temps than unpainted fins (when using an IR temp gun) due to the different emmisitivity figures of silver to a darker colour. If you paint a block dot of nail polish or similar on your unpainted fin then shoot it with your IR gun you will get a higher reading, dosnt mean the actual internals are any hotter...........

Don't mean to be arguementative (ok, maybe I do, but I want to be polite) but I calibrate the IR temp sensore to ambient temp inside a known climate (my living room). I.E. - the thermostate in my house set to 74 degrees, the emmisevity adjusted until it reads 74 on an engine that's been inside for a good while. The other side of that - I've never had an engine with painted heads, so I'm not speaking from personal experience, just the advice given by folks with much more experience than myself - So I could be off; but in theory the thought made perfect sense to me. Raw metal sure seems like it would conduct heat better than painted, as paint doesn't conduct heat as well - I believe that would make it an insulator. Like I said though, I could be off, or the difference could be nominal.

I still like having a sleeper in the cowel but that's just my taste. I've always wanted a hot-rod Cadillac.

[atique]

Why not just wait to buy the DA 85??

[atique]

DA 85
9.2 HP
weight:4.3lbs

3W85
9.0 HP
weight:5.23lbs

So I would go with the DA 85 from what i have seen from the specs, but thats just me.

[Flyinrazrback]

He didn't ask about the DA 85, he asked about the 3W 85.

[atique]

	Quote: Originally Posted by Flyinrazrback
	He didn't ask about the DA 85, he asked about the 3W 85.

I was just giving him some advice.

[JVDO]

	Quote: Originally Posted by atique
	DA 85 9.2 HP weight:4.3lbs 3W85 9.0 HP weight:5.23lbs So I would go with the DA 85 from what i have seen from the specs, but thats just me.

I first want to see that in real

[notorious_benny]

From my highschool physics I will agree that a dark colour will absorb radiant heat faster than a reflective colour, however the dark colour when there is no radiant heat source incident upon it... ie the sun, will also work the other way around and dissapate heat in the form of radiant transfer faster than the reflective colour.

So in a cowled installation, theroetically the dark colour will cool more effectively from radiant heat transfer alone than the reflective colour.
Of course our 2 strokes rely much, much more heavily on convection of heat by airflow through the fins rather than radiant heat dissapation.

As long as the paint isnt acting as a conduction insulator, where it is preventing the metal from conducting the heat to the very outside(air), then the painted fins will not make the motor run any hotter than unpainted.

You can see this theory being applied in high end computer components, my new, fancy, very hot running graphics card has a fan to keep it cool but also an additional heatsink which happens to be painted black of all colours.

Owning a CS (as in competition series) 3W motor I can tell you the paint is incredibly thin, and will sratch off quite easily to show bare metal underneath, so I doubt it is acting as a conduction insulator.

In summary, the colour of your cylinders has little to no bearing on how hot your motor gets or how efficiently it cools. The primary method of heat transfer in our 2 strokes is convection not radiant heat transfer