PT46

Im thinking im going to buy a 40% with a 3W 140 in it. I will use that for the rest of the flying season, but over the winter if I get the plane, I will switch to a DA 150. My question is do the motor mount holes line up the same on both engines that I dont have to change anything around for switching. Just bolt right in place??? Also are the mufflers the same size?? Like with the mufflers that come with the 3W 140 mount to the DA 150?? Finally how much more power does the Da 150 have compared to the 140?

Supermod56

My Feedback: (36)

I THINK it will bolt right up, but not sure. I do know they came out with the DA to one-up the 140, so I would think it does. And NO, the mufflers won't fit, DA has straight ports, 3W's are angled. Power?? The DA has more than the 140, or you could just get a 3W 150 and I know that will bolt right in, mufflers are the same. Don't want to start the DAvs3W thing again, that has been beaten to death. But I would stick with the same brand if it's a direct bolt-in. Nothing wrong with the 140, you might just want to leave it in there and save some cash, beacuse you will have absolutly no luck selling the 140, trust me I know!!!

Tom

DadsToysBG

My Feedback: (35)

If you fly it and like it why switch ? Dennis

BBW Walt

My Feedback: (11)

The power difference between the 140 and the DA may not be worth the added expence. 140's run better than most would believe. In my experience the difference is not much...

John Murdoch

My Feedback: (11)

Aren't the bolt patterns different for the 3W 150 and the 157? Now that doesn't make sense at all.

mglavin

My Feedback: (31)

The 3W mounting bolt pattern for the BIG blocks is 80mm wide x 90mm tall across the board on all their engines up to the 200 twin. Simply plug and play.

John Murdoch

My Feedback: (11)

Michael.. You're absolutely correct. A friend of mine said he wanted to change out the 150 for the 157 but the bolt pattern didn't match. I believed him. I should check my facts before I mouth off, huh? But thanks for the affirmation. 100 smacks about the face and head

PlaneInsane

My Feedback: (5)

The 157 mounting dimensions ARE different from the 150 UNLESS you have a rear inducted 150, then its the same. The 157 is 1/16" shorter than a DA150 and about 1 oz. lighter. I know because I have all of these motors.

Rich

rcblimppro

To answer the original question, When the DA was designed it was supposed to be a direct replacement for the 3W 120 that everyone was running at the time. The 140 was introduced just before the DA 150 hit and all 3 along with the current 3W 150s have the same hole pattern. A good running 140 will swing a 30X10 while the DA 150 will swing a 32X10. I know this will stir a debate but those are the props that were being used by most of the guys using those engines.


Shawn

PT46

thats good if I get a DA 150 for it over the winter it will just mount up. I am going to fly it with the 3W first and see what happens and what I think but I really like DA's. no not a 3W is better then DA vis versa thread.
I have another question, on my DA's I run 100:1 ams oil in them. Can I do the same for the 3W 140? I saw on the 3W site they said 50:1 to 80:1

Supermod56

My Feedback: (36)

Amsoil should work at 100:1 in the 3W, although I wouldn't do it, I have used 3W, Klotz, Bel-Ray, etc. in all mine at 50:1, they all work good. 30X10 works good on the 140, I ran a 30X12 Menz on mine, it seemed to like it. Then of course I HAD to have the 150 as soon as it came out, didn't notice a whole lotta difference. Now when I went to the 200, I noticed a ton of difference!!!!!

Tom

mglavin

My Feedback: (31)

Seems your right I had compared the specifications for bolt patterns on the Cactus site, their info must be incorrect as I see on the 3W site they are the same as the rear induction engines as noted, 100mm wide x 60mm high. I was planning on simply removing and replacing a standard 150 myself, oh well.

jsm77777

My Feedback: (4)

100:1 Amsoil is fine for 3W's. Have done it for 8 years, and put over 175 gallons through one engine. No problems. Scott

rcavi8ter

My Feedback: (19)

I know of a couple 140's that I would put up against any of the current 150's. Walt knows of at least one I am talking about. Big Lew is is running it in a DP 40% Edge at around 45lbs and it has more than enough power and he is runninga 28.5-12 3 blade.

malley56

My Feedback: (13)

I would try that 140 out first. My 3W 140 spins a 32x10 MenzS @ 5650 rpms with headers and cans. It hovers my 40% at about 1/3 throttle. More than enough power.

Good luck!

rcblimppro

Thats very close to what my DA 150 spins that prop with mufflers. Not interested in an engine war here but when comparing the two we really should be sticking to engines with the same setups.


Shawn

malley56

My Feedback: (13)

Yes, I agree no war. DA150 is a great engine and more powerful than a 3W140. I was just making the point like some of the others that it might not be much of a gain for that much investment.


I'm a giant scale modeler on a budget. So I had to buy a used 3w140(got it at a great deal) Other wise I would have a 150. Although it is a nice feeling to know that you have very close to the same power as some people who paid twice what I did for a new engine.

rcblimppro

I agree, spending 1600+ for just a small amount of gain may not be what everyone would do here. If the airplane is in the 35 to 37 pound range and the pilot is not flying above intermidiate class I would leave well enough alone. That is the engine is running well. I will assume here that it is. I would not run 100 to 1 through a 3W. We have had a couple of guys here in Cali that have and when they needed service on the engines they were charged full pop for the repairs.



Shawn

flyinrazrback

My Feedback: (69)

I used to run amsoil 80:1 no probs in all my 3Ws, but now I use belray MC-1 @ 50:1 and like it a lot.