This information comes from Les Smith of Performance Unlimited. It speaks about the progress of the 32 cc to 35 cc Pipe R&D work. This tuned pipe's design follows from the research developed over the last year.
"The R&D design and the testing of our new Stainless Steel Pipe is finally being finished....below is a synopsis of the R&D testing ...
The final results are more than impressive to say the least. Ray's 20 lb 53'' Delta Force Annihilator Mono started out with a top speed of 51 mph with a modified 30.5 cc engine using a QD Hot Pipe. He upgraded the displacement to a 35 cc engine and tried the following pipes from QD, Insane and Zipp Kits with no better performance than the 30.5 cc using a QD Hot Pipe, the JB pipe gave a little improvement over the others and all running in the 17k-18,600 rpms, however...the Pro-Modified 35 cc engine was producing the same power as the 30.5 cc, since the same prop was turning the same rpm as the 30.5 cc and the 35 cc was also showing a lot of increasing engine heat from the CHT sensor readings were going above 205° and then the performance of the engine was sluggish and the top end power dropped off.
We went through 7 different designs of the pipe as well as several different shapes, angles to mention a few and the performance of the 35 cc engine came alive and we kept testing in the direction of the performance increases and the CHT temps were monitored closely to insure no melt down will occur at WOT for an extended period of time that was way beyond any heat racing or marathon running time frame. The air temps in the 3 digits and altitude changes from sea level to Las Vegas did not hinder the performance gains with the new pipe.
Rays heavy mono now has a speed of 65.6 turning a prop with more pitch and rpms around 20k-21,400 with no over-heating and plenty of bottom end to more the heavy hull.
This pipe is not a spin off of a QD Pipe, Zipp Kits Pipe, Insane Pipe or a modified pipe from those on ebay as some have done to sell pipes by modifying them and claim this is the pipe for the 32-35 cc or to claim their pipe works on this size of engine.
In the R/C hobby most pipes will work across several different engine displacements, however only a pipe that is specifically designed for the engine and its displacement will work even better.
There are several guys that have been there when Ray first started the testing and have witnessed the performance improvements during the R&D testing and have visually seen the results of the pipes performance even during NAMBA District 9 races.
We are pursuing to have this 4 stage pipe stamped out of Stainless Steel and we decided on this method, since the inside of the pipe is smoother than a bunch of welded stages and the angles are radius to the other areas along the pipes length, so the pipe will have the welds similar to a QD Hot Pipe and have the flared diffuser that you can see without the welded stages and of course be lighter in weight too.
The 32-35 cc Pipe uses a 1" header
All clamps are Stainless Steel
Muffler on our pipe has an integral stinger
Weight of the pipe with stinger & muffler is 17 ozs
JB Pipe is 18.8 ozs and QD is 15.4 ozs
Below are photos of the visual differences between the tuned length and / or the pipes shape and length of the QD, JB and our pipe.
Top Pipe is Our Stainless Steel Pipe, Middle Pipe is a JB Pipe and the Bottom Pipe is a QD Hot Pipe."