New reeds in old block

[Frank Acampora]

Because it has been bothering me for some time as to whether or not the new square reeds are more responsive, I decided to transplant new style square reeds into my trusty old Chrysler 140 and see if they made any difference.

Since the old reed blocks are five petal and the new reed blocks are four petal, the block is not relieved to clear the reed screws. And, since the vee block mounting screw bosses are longer on the new vee blocks, they will not fit into the old style engine. Instead of relieving the crankcase to clear the screws as the manufacturer did, I elected to buy flathead screws.

Hmmm--National fine thread 4-48 and only available in stainless. Also only available in slotted flathead. Also 15 bucks for 50.

Photos show the completed vee blocks which now will fit my old Chrysler. They also show how I countersunk the reed stop plates to accept the screws and ground off the extra length from the bosses

View attachment 97562View attachment 97563.

NEXT: I will install them and report on the results of the experiment. Things that make you go "Hmmmmm!"

 

[BobList]

Re: New reeds in old block

heh heh.. Just can't sit still, eh?... I think you are probably the best 2-stroke R&D dude out there, my man!!

Bob List

 

[Frank Acampora]

Re: New reeds in old block

Well--tested the trusty old 140 with the square reeds and rubber covered reed blocks today. Depending upon the accuracy of the tachometer, they increased wide open throttle RPM by about 100-200 RPM. 5200 vs. 5000 with the same prop and load. Significant? Eh! Not for the fuss. I really didn't expect too much and 100-200 IS an increase, but 500 RPM would have made me happy. Now, perhaps when I put that engine on a smaller hull and get it to turn 5500-6000 they will make a difference.

I have the engine on a 21 foot cuddy and I can not feel a difference in hole shot. I can't say if the low rpm full throttle and torque were helped. On this set-up, probably not much.

SO: Try it if you want, but don't expect too much.