YS 1.40 DZ in a .60 size P-51? (Full Version)

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A 4 liter V8 eater -> YS 1.40 DZ in a .60 size P-51? (8/10/2007 5:47:49 PM)

I was wondering if anyone has put a YS dingo in a .60 size (~65" wingspan) mustang? How did it fly? Any guess on top speed? (I'll have a 15.5x12 four blader) I have a YS 1.40 DZ arriving today and I plan on swapping out the current 1.10 fz. The plane is already stupid fast with the 1.10. There are two reasons why I'm doing this which are, A. to have a more scale prop size & B. to chase down some of the jets at my club. It is more involved than it sounds though (but not hard, its just that it isn't a bolt in like going from a os .60 to a ys 1.10):

1. reinforce firewall
2. increase fuel capacity
3. install soft mount
4. rebalance (will likely require ALOT of tail weight)

Becuase of the added weight I will also have to beef up the cheesey gear which means at the very least:

5. stronger control rods
6. metal gear

God, I would love to get some input or see a video of a similar setup before I start, even if it's not on a 'stang but another .60 warbird.



bl10 -> RE: YS 1.40 DZ in a .60 size P-51? (8/10/2007 9:16:11 PM)

Good luck chasing down the Jets. All the "Fast" guys out here, Los Angeles, are well over 200 mph. My Q40s can give them a run for their money but they are still faster.

Barry



DHG -> RE: YS 1.40 DZ in a .60 size P-51? (8/10/2007 9:46:45 PM)

The biggest problem with turbines is that at 100% throttle, they go so fast the control surfaces flutter and fall off. So, instead of trying to compete with that kind of speed, I decided to just build sloppier. Now my stuff falls apart at full throttle, too! [:D]



p.s. Just kidding ... don't try this at home! [:-]



Tony Pacini -> RE: YS 1.40 DZ in a .60 size P-51? (8/11/2007 1:25:33 AM)

I believe you'd almost have to scratch build an airframe if you want to go faster than a turbine; the airfoil on your P-51 is probably too thick to be faster than a jet. You'd need a cleaner airframe (not necessarily "scale") as well.

We run YS .91-120s on the World Mustang ARFs which are .46 size (I think), so a 1.40 in a slightly larger Mustang wouldn't be horrible. When I built my last two I recessed the 1.10 into the firewall (to avoid having to move the engine forward), mounted the servos aft of the TE, and put the battery right in front of the stab. By using this arrangement I was able to avoid adding any tail weight. We don't use soft mounts, but firewall reinforcement wouldn't be a bad idea.

The 4-blade prop will look great but it won't be as fast as a 2 blade. I use an APC 14x10 on my 1.10 and APC 14x13 on my 1.20, while by buddy's got a heavily-reworked YS 1.20 (actually about a 1.34) that'll spin a 16x13 @ 10,500 on 80%. It is SERIOUSLY fast but the TBO is only about 30 runs. Yes, it's worth it. [8D]

If you really want to go fast (with a YS in a warbird) you'll have to resort to using a bit of nitro. I generally race mine on 55-65%. No, they don't last long that way, but they're faster. We use 30% heli (all-synthetic) for break-in and sport flying. The YS 20-20 blends are just too messy in my opinion.

Good luck catching the jets. Even if you're not faster, you're still cooler 'cause you're flying a prop-driven warbird [:D]



iamtom -> RE: YS 1.40 DZ in a .60 size P-51? (8/11/2007 2:15:30 AM)

"Good luck catching the jets. Even if you're not faster, you're still cooler 'cause you're flying a prop-driven warbird "
Yes, You will always be cooler with a prop and a warbird.
Tom



Clark L -> RE: YS 1.40 DZ in a .60 size P-51? (8/11/2007 3:06:47 AM)

Jets are for kids...



PJ_TankPilot -> RE: YS 1.40 DZ in a .60 size P-51? (8/11/2007 6:49:04 PM)


quote:

ORIGINAL: A 4 liter V8 eater
I was wondering if anyone has put a YS dingo in a .60 size (~65" wingspan) mustang?


I had a 1.40 DZ in a .60 size plane. It was scratch built but not a mustang. Previously, the plane had a 1.20 FZ. The conclusion I came to is that the DZ is not good for racing. The additional weight and fuel consumption were problems. Also, you will not get the RPM's required for racing from this engine. Your only hope is to nitro up and swing a big stick.

I sold the DZ. [:(]




A 4 liter V8 eater -> RE: YS 1.40 DZ in a .60 size P-51? (8/14/2007 3:39:36 AM)

Ok, scratch chasing the jets I guess. At least I'll get part of the way there without spending all the extra cash. Instead I'll have a not quite as fast plane and a new Harley Davidson. Any guess as to what the max level speed will be? I've heard anywhere from 120-150 with the 1.10 FZ (are these #'s realistic). The 1.10 has I think aroung 2.2 HP (right?). I read the 1.40 DZ has 3.5 HP.

One thing that worries me is what my landing speed will be. The engine weighs .5lbs more, so I assume I will have to add around .25 lbs to the tail (which I plan to be batteries for the most part because I have a mental block with adding useless lead). There will also be added weight associated with the new retractable gear.



Tony Pacini -> RE: YS 1.40 DZ in a .60 size P-51? (8/14/2007 4:05:47 AM)

eater-

Based on course times (and what other planes turning those times have radared) our 1.10 Mustangs are around 130-140 mph (faster than a 424 Q-500 but slower than a 428 Q-500). The bigger engines CAN go a little faster because they seem to tolerate higher nitro than the .91-1.10s.

Yes, it might land like a dumptruck with the extra weight. Put everything you can in the tail (servos, battery) and get the engine as far back on the mount as you can (even if you have to trim the mount and recess the air chamber and carb into the firewall). I despise having to add ballast and will do almost anything to avoid having to do it.

Regardless of how fast it is, you'll garner plenty of attention when they see all that engine hanging out of the cowl. It'll sound mean, too.

Post photos when you can-



A 4 liter V8 eater -> RE: YS 1.40 DZ in a .60 size P-51? (8/24/2007 4:20:07 PM)

It ends up that this is going to be a pretty involved install. The distance from the prop mounting surface to the firewall on the P-51 I've got is supposed to be 5.25". it ends up that the 1.40 DZ is a C-Hair longer than 5.25". Before I purchased the engine I saw that the 1.10 FZ I've got on the plane has about .5" of room behind it and thought there was no way the 1.40 DZ was going to be that much longer. Well the real problem begins when I hold the Du-Bro soft mounts I bought up to the DZ. It ends up the the DZ has to be mounted at the very tip of the mounts so that various protrusions on the engine will not interfere with the mount. This means that where the mount would attach to the firewall is 1" behind the engine (meaning that at best the Prop mounting surface would be 6.25" away from the firewall aka sticking 1" out of the cowl). The solution I've come up with is to actually mount the soft mounts behind the firewall and cut holes in the F-wall for the mouning surfaces to stick out. I think I'm going to wait till winter to install the motor, and for now I'm going to install my Frank Tiano retracts, robostruts, stiffer retract control rods, high torque retract servo, and shim the retracts to stick out more toward the front of the plane. Hopefully all that will nip the floppy retract/nose over problem in the butt.

-John M.



jetjockey -> RE: YS 1.40 DZ in a .60 size P-51? (5/13/2008 8:42:41 PM)

Don't want to jump in and steal this thread, but my son and I used to race Tony at Tucson in SWRA a few years back. We were running YS 120SC's ported and polished on 65% nitro (sometimes 70%). We usually ran a 14/13 or 14/14 APC prop on them - depending on which airframe needed which prop - believe me, it does make a difference. The engines would usually turn around 9500 static on the ground, and I felt they were unloading around 1000 RPM in the air. I never let the engine turn higher than 9600 static because we floated a couple of valves when racing, and that ain't good! We were running scratch built airplanes with around 600 - 630 square inches of wing area with flaps on a 13% modified Clark Y airfoil. They landed a little hot, but were manageable. Our fastest airplane was a clipped wing Spitfire that was radar measured on a level pass at 176 mph (Gold class) and we had a silver class Mustang (World Jet) that was clocked at 154 mph - both running the same engine and nitro.

The reason I'm telling you all this is to make some recommendations. First of all - lose the soft mounts. All our engines ran better bolted solid to beam mounts. Second, don't hesitate to tip the nitro can. Our engines withstood 75% nitro and are all still running fine(although no longer racing, they are still very strong). Thirdly, let the engines breath by polishing the intake and exhaust ports. If you look at the YS intake porting, you will see sharp corners and right angles. Take your dremel and clean that all up - round the corners and open up the tubes, but be careful, if you go through the material, it will cost you a new head. I had to buy several before I got the hang of how far to grind, but it is definitely worth the effort. We experimented with putting 140 cams in the 120's but couldn't tell a lot of difference in the power. Mostly it is the above changes, the amount of nitro, and the prop pitch which gives the power.

Good luck with your racing activities.

I'm now flying jets, but still miss racing the props.

Regards, Les



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