whee wrote:Dons Dream Machine will build you a certified stroker C85. Bob Borrows will build you a experimental stroker C85.

Is Bob Borrows the Bearhawk guy??

PatínLoco wrote:

whee wrote:Dons Dream Machine will build you a certified stroker C85. Bob Borrows will build you a experimental stroker C85.

Is Bob Borrows the Bearhawk guy??

Yes. He came up with a stroker C85 with custom pistons for his LSA and figured it was 110ish hp.

That sounds awesome!! That's exactly what I need! Thanks whee!

When I had an L4, I thought it was the greatest backcountry plane there was.

Then traded up to a SuperCub for more range, and had a new greatest ever plane.

Wrecked the Cub an bought a T cart to fly while Cub was rebuilt, an damn.. Had a new greatest ever plane..

I think its just best to love the hell out of whatever ya got.. Seriously..

Coyote Ugly wrote:
I think its just best to love the hell out of whatever ya got.. Seriously..

Best advice I've ever heard.

I must admit, that's some of the wisest stuff I've ever heard. If I think about it, I can apply it to about everything in my life, specially my wives!!!

On the 9.5 O-200 use a Mac 7440 instead of the borer (just repitch the metal prop off a 65hp Cub from 43 to 40). A 7440 Mac will out pull just about anything up to a static of 2750 rpm. Above that, a Mac 7535 will pull better. With the 9.5 O-200, that will get you off the ground about a hundred feet shorter than a 160 hp SuperCub. You'll be 25 feet in the air when he breaks ground. Based on back to back takeoff tests with 165 pound pilot. SuperCub broke ground in 190 to 195 feet. J3 broke ground in 65 to 70 feet. On grass with 8 kt wind.

Hey JimC, thanks for your input, as usual. Sorry I hadn't read it sooner. I will definitively take that into consideration. I like it.

whee wrote:The C85 with O200 crank and Bobs pistons will give you the same 110ish hp and not add weight.

I herd that the stock certified 85 stroker puts out almost a hundred hp. After flying a j3 with a c-90 and bushwheels and flying a j3 with dons stoker, completely stock, the c90 does much better.

Less - more like 97hp from what I understand. But that has more to do with the rpm limitations and the props. Surely you can do better with experimental options - but I'm not sure how far I'd want to step out on that slippery slope.

Tom wrote:

whee wrote:The C85 with O200 crank and Bobs pistons will give you the same 110ish hp and not add weight.

I herd that the stock certified 85 stroker puts out almost a hundred hp. After flying a j3 with a c-90 and bushwheels and flying a j3 with dons stoker, completely stock, the c90 does much better.

The big question for me is to modify the C85-8 or the O-200 since I have both. The aircraft is experimental, so just about everything goes!!

Non-electric O-200 is 1.58 pounds heavier than a non-electric C85-12F and 0.5 pounds heavier than a C90-12F.

C-85 and O-200 have similar cam timing and profiles, but C-85 valve lift is only 0.382" vs O-200 lift of 0.410", so the 85 and 85 stroker don't breathe as well. Difference is most obvious during side by side takeoff and climbout.

O-200 produces more power and torque than a C-90 up to about 9000 DA or thereabouts (too lazy to look up the actual cross over altitude, but the crossover is at about 21" MP). For takeoffs from airstrips above 9000 to 9500 feet, I'd prefer a 90. Below that, an O-200.

Everyone here is talking about horsepower, thrust, torque, and JATO. Anyone want to think about glidepath control, drag, and getting a very light wing loading airplane into the kinds of places that those hopped up 300HP C-85's will get the Cub out of??

Some of the L-2's had spoilers, most of which were de-activated for the wrong reasons. they were there for a reason, putting a light feather of an airplane in a tight spot.Unfortunately the L-2 can't get out of many of the places it can get into. (L-2 owners should contact Terry Bowden in Texas to fix this problem with an 85-90HP upgrade, works like a charm)

Patin Loco, it may be a wise decision to keep your L-4 as a classic, un-screwed-with airplane. You'll never make it into a Super Cub without destroying the classic part IMHO.

Another option you may want to think about instead of buying a Super Cub is the Zenair 701 and 750 airplanes. 1/3 of the cost of a Super Cub, and really good for a cheap, knock-around, fun back country machine.

I saw a Zenith 750, "SkyJeep", in Wyoming the other day. The builder pilot and his wife were just returning from Johnson Creek and were in the process of unpacking it. I complimented them on all the crap they had on board! Packed to the gills, and powered by a 130 HP UL. Nice to see a design in the real world as opposed to internet chatter or on a website, this bird seemed to be working well for it's owner. No slats BTW, took them off he said.

Only obvious external difference between a 65 hp A-65 L-4 and a 110 hp O-200 L-4 is that the exhaust collectors sit 5/8" lower on the 110 hp (just as they do with a C85-12).

you can switch to either engine in a weekend.

110 hp takeoff distance, grass, no wind, average temperature, low altitude, will be 70 to 225 feet, depending on weight. Landing, same conditions, 125 to 225 feet. I've always preferred that a plane be able to get out shorter than it can get in.

No one has said anything about carburetors. Is there a reason to stay with the Stromberg, or is it advisable to go to a Marvel Shebler? Does this factor into the performance?

They both work fine. With an O-200, I like an MA3-SPA 10-4115 with the original 2-piece venturi.

EZFlap wrote:Patin Loco, it may be a wise decision to keep your L-4 as a classic, un-screwed-with airplane. You'll never make it into a Super Cub without destroying the classic part IMHO.

I really have been thinking about leaving it classic, and finding a "real" bush airplane instead. I'd hate to modify a beautiful classic bird. I agree, EZ, I'll never make it into a Super Cub. Well, it's a thought anyway.

A J3 with a 9.5 O-200 will get off the ground a hundred feet shorter than a SuperCub (based on side-by-side takeoffs against a 150 SuperCub with VG's, and a 160 SuperCub without. Rate of climb at sea level will be about 900 to 1100 fpm. I've used a J3 for off-field work since 1965 and for that, far prefer one to a Super Cub when lightly loaded.

It remains completely convertible back to an A-65 with no modifications..