As some of you might know, I have had a Brodak 40 from the very first bunch that came in.  It had given me troubles from day one and NEVER ran a good 4-2-4 break, but would lose  appx 2000 RPM when going into the 2 from the 4 and then would take three or four laps to go back to the 4. I posted on various forums the problem and symptoms and received a LOT of suggestions (some of which would seem to me to be painful if attempted) and tried most of the more sane ones.  Nothing solved the problem.
  After three years of disassembling and reassembling the engine to add gaskets and remove gaskets etc etc,  I would not DREAM of trying to get some sort of warrantee from the mfr.   Mr Brodak apparently heard of my problem, probably from Mr Bob Zambelli, and  now the problem has been rectified.  Mr Brodak is VERY concerned about the quality and servicability of his products.
  I was very supprised.  I have NEVER bad-mouthed nor complained about the engine other than trying to find and cure the problem. And I think that such actions never accomplish anything other than cause hard feelings.

  Thank you Mr  Brodak.

  Marvin Denny   aka Bigiron

I think the latest version is a real stump puller.

I had the exact same problem with my early B40.  Turned out to be over .070 head clearance.  It would go from a strong 4 stroke to a weak, anemic 4 stroke when it leaned out in maneuvers.  Tom Hampshire told me the head clearance is supposed to be in the 12-14 thou range.  A little turning on the head to get the right head clearance worked some real magic on the engine run.

Just got back from flying my three times crashed/rebuilt Oriental with B40 and stock muffler, Zinger Pro 11x5 at 9000-9100 rpm, Powermaster 10/22 (50-50) fuel.  Weight is 46 oz. but no lack of power from the B40.

I've been flying 49oz Chipmunk with B40 and a gem of a prop discovered by the West Coast crew: thunder Tiger 11x4.4. I've flown it with fuels with oil content anywhere between 18% and 28%. Anything over 25% changes motor characteristics(less power).

Here's the link to where I got the props:

Singles: http://www.thundertiger4u.com/cyclone-prop11-p-7664.html
6-pack: http://www.thundertiger4u.com/cyclone-props11-p-7682.html

Wow!  They discovered that prop?

Bill Wilson has been running it for two years...

You see!!! This just proves my hypothesis: West Coast boys discovered Bill with the magic prop! Too bad B40 can't spin Bill. Too much prop or too much Bill, I can't remember which one. 

Yea, I started using that prop at VSC 2 years ago. A lot of guys there were running it. Sure seemed to do well on my PA 40UL. Thanks to Bill Rutherford for that one.

I really think it was RO that found that one, but Bill finds lots of stuff that spreads across Texas and then, ultimately across the country (Polycrylic, top feed Harbor Freight guns, etc).  He is like an eccentric genius.  Maybe someday he will go to the Nats.  He was at VSC...

Either way, I here it works good.

I cannot see spinning a Brodak 40 that fast.  I am trying the TF 11-6 this weekend.  It looks awesome.  I ran an 11-5 this last weekend, and it was not fast at all.

Brad,

I thought the same thing. Try it.

Oh, I am gonna!

The other engines based on the Aldrich 4 port design (DS 54 and DS 60) are both low RPM grunt 4-2 engines.  I think the Brodak is the missing cousin here.  The recipe for the DS engines are typically the TF props, and frankly I am starting to believe that the TF props are the best wood props out there.

I think that the reason so many people are saying the Brodak 40's are gutless is because they are being told to run 4 pitch.  Then they end up with a 2-2 engine that has no grunt.

I told John I am going to write up the Brodak 40 for CLW.  I think that the setup needs really needs to be visited.  For what it does, there is nothing on the market better than a Brodak 4o.

I think that the reason so many people are saying the Brodak 40's are gutless is because they are being told to run 4 pitch.  Then they end up with a 2-2 engine that has no grunt.

I've been running 4.5 pitch in 4-2 mode and it was not gutless at all. Rick Campbell flew Oriental ARF in constant 4 and it was no slouch either. We've both use APC 10.5x4.5 with good results but then I've discovered 11x4.5 TT and was very impressed.

What kind of line length are you gentlemen running? B40 w/4.5 pitch will give 5.1 lap times on 62' lines(center to handle). I can't imagine why you would need more pitch.