Brodak 40 vs OS LA 40

I wish to hear from you the pro's and con's about these two engines. I want to use one on a Profile Cardinal. Which one would you use?Thanks!

The Cardinal is a good size plane and, as I recall, the prototype used the Brodak K&B 40. The New Brodak 40 is considerably lighter, made to fit externally in a OS 35S mount (and with about the same weight), internally is like a FP 40, but timed more like the Brodak K&B 40. (OK, do I have you confused. I have me confused). That said, the new Brodak 40 should do a good job. The LA 40 is heavier (the plane will take the weight) not as good quality wise, and some, including me, would recommend going to the 46 if you were going to make that choice. The weight is the same, but it makes better power. Price wise, the LA wins. Quality wise, the Brodak 40 is much better. That would be my choice of the two.

The Cardinal profile prototype Windy built used the Double Star .40. Johns plans show the K&B .40.
The Brodak .40 seems to do well powering small classic planes like the Nobler. The LAs would be my choise for the Cardinal. Some thought should go into using the LA .40. 0.15 lines compared to 0.18 for the .46. For me HP usually rules.
This is my Cardinal when new.

Actually, Windy first used the K&B .40S in the Brodak Cardinal prototype. I have a loaner video from him that shows what he did to install the 2Star .40 after it was built around the K&B and flown that way. Anybody who doubts this, I'll mail you the tape, just email me with your snail address. You return it to Windy or pass it along to somebody else who will. Anyway, I'd vote for the .46LA, but a .40LA would be next best. Steve

My error, thanks for the info Steve.

Yes I have a trim video that I bought from Windy and it has the Cardinal with the test and trim flights .He actually does part of the brake in of the K&B 40s on the tape.I put the K&B 40s in my Cardinal also.It is a great running motor just lacking power.It now has a LA40 mounted in its engine bay.

As an aside on the K&B 40. I never did get the stunt version of the motor but I have several new and used RC versions .
So where is this going well Bob Davis made a diesel head for the motor and I got to be the test man for it. I looked at my figures for this motor and also had done a vidio for him, and with an 11/7.5 it was turning 13,100 which is not too shabby by anyones tach. Incidentally this was with the long tuned muffler that came with the motor. It is not true that diesels don't benefit from some tuning. Given the lower pitch props that are used in our sport it would have been some insane figure, but at that time I was not into C/L.
I was trying to compare mine with a stunt version but I never got one to do the side by side comparison and really didn't get too serious about it as the C/L version was a dead issue.
Oh there is another part to the diesel story. We tested the one motor to distruction and on a really well set and howling run it blew the top of the motor,case and head, completely off. I never saw that in any diesel or glow that I had ever run. God knows what it was turning or what the pressure was in the motor but it was in October the humidity was low and all motors were really cranking extremely well that day
To Bob Davis and Bill Wiznewski's credit they replaced the motor for me.
I have one converted to C/L but haven't run it more then once to see how it was. I really would like to see a Brodak version to do a direct comparison, not that it would really be relevant, but is the kind of thing that I enjoy doing.
So Steve do you still have one that you want to get rid of. Perhaps we can put this to rest once and for all

Unless you already have both engines, I would suggest the LA .46 - bigger lines and all.

It's a killer combination.

My vote would be the LA .46, too. I would imagine that there are a dozen or so of these flying around here with power ranging from Sleep's feeble ST .35 to a fairly stout OS .52. If you glass the fuse as Bill and Noel suggest, and build in a fairly normal manner, they tend to be a bit heavy. The .46 seems to perform vey, very well with no fiddling. The Brodak piece, though well made, seems a bit shy on horsepower for a big and heavy airplane, (mine flys good, but I know that an LA .46 will be BETTER). The LA .40's don't seem as consistant?

Windy did fly the prototype with the K&B, and it flew well when he flattened the prop. The DS .40 that he has was a terrific piece, but shy of some power, although he developed a "work around".

See Ya

I went by Mike Haverly's today, and he said that his .40LA runs exactly like his .46LA, just a bit less grunt, as you'd expect from the displacement difference. Putting a lot of effort or money into props (to make up for not enough engine) is not a good plan for pilots below Advanced or even Expert class, IMO. Steve