Hi Guys,

I'm 1/3 of the way into a build of Bradley Walker's Zone II as published on his website. For possibly the first time ever I'm building almost exactly to the plan, just some tweaking to account for non-lasercut parts. The big question is in engine choice. When I started, the intention was to fit my GMS76 (apparently a clone of the Tower 75?) which when pared down is similar in weight to Brad's original choice of Saito 72.

However, the GMS is an unknown quantity in stunt so I'm getting cold feet about it.

The obvious choice is to go with the Saito 72 and I'm very tempted except for a few things:
~They're not cheap (although probably save fuel costs in the long run)
~There isn't much of a knowledge base locally on them
~I have zero 4-stroke experience, so the Saito is also an unknown quantity for me
~Some fliers who swore by them a few years ago have moved on to big two-strokes since.

Other choices might include my MDS58 or a big Stalker, but they are secondary options at this stage.
Or one of the other four-strokes, the Satio 62 for example.

I guess I'm looking for confirmation that the 72 is the way to go, or reasons why it might not be the best option for this particular model, especially any thoughts from the City Smasher himself.

What say you?

Also include Gordon Tarbell in your list of references, especially for the Saito .72 - - And Bob Reeves, too

Well, I think I've answered my own question by spending time yesterday on the lathe getting the GMS 76 into stunt trim. Stuffed boost port, sleeved crank hole, machined a couple of unnecesary ounces off the head and case and made the delrin venturi. By the time I'm done with the exhaust stub it will be down to 16oz and ready for testing. Needs some head gaskets yet though.

If it turns out to be a dud, I might then go with a Saito but for now it might be best to stick with what I know, which is big, dumb, muffled 2-stokes.

A question remains for Bradley, what is your current first choice powerplant for your own frontline models? I gather the Satio 72 no longer rings your bell like it did a few years back. I look forward to seeing pics of your latest creation.

Thanks all. I'll post some pics when it comes together.