Search found 614 matches

by Slidin Gator
Mon Jul 15, 2019 9:03 pm
Forum: Aircraft Power Only
Topic: Lycoming 4cyl
Replies: 17
Views: 855

Re: Lycoming 4cyl

Flange under flywheel, or belhousing flange for a better term. You got the eye for sure! I see it now. So do y'all think the spare cylinders I got are 435 cylinders, if so what is involved in putting them on my 290 ? Maxx, 435 is the 6 cylinder version of the 290. Chances are that the cylinders are...
by Slidin Gator
Sun Jul 14, 2019 7:41 pm
Forum: Aircraft Power Only
Topic: Lycoming 4cyl
Replies: 17
Views: 855

Re: Lycoming 4cyl

Thanks Twister.
by Slidin Gator
Sat Jul 13, 2019 8:07 pm
Forum: Aircraft Power Only
Topic: Lycoming 4cyl
Replies: 17
Views: 855

Re: Lycoming 4cyl

O-290 GPU, has a flange under the flywheel I'm sure. John, I'm curious, what are you seeing in the pics that say this is a 290? Valve covers and external hex nuts look like a wide flange 320 or 360 to me. I'm not sure about the oil pan. The valve cover on the spare cylinder matches the O-435/290 st...
by Slidin Gator
Tue Jul 09, 2019 10:34 pm
Forum: Automotive Power Only
Topic: LOW TORQUE LS Engine Build
Replies: 51
Views: 2803

Re: LOW TORQUE LS Engine Build

Simplifying things for clarity. Deleted the SAE figures, just metric. Do you dispute the following? 500 Ft-lbs, converted to 678 N-m and plotted against kw.

Image
by Slidin Gator
Tue Jul 09, 2019 8:21 pm
Forum: Automotive Power Only
Topic: LOW TORQUE LS Engine Build
Replies: 51
Views: 2803

Re: LOW TORQUE LS Engine Build

I can see how it might work out different in metric, now. but the HP vs tq equation remains the same. This is so wrong as to be laughable. You clearly do not know what you are talking about. If you were to provide scales in proper increments, you would see that the relationship remains the same. Yo...
by Slidin Gator
Sun Jul 07, 2019 8:01 pm
Forum: Aircraft Power Only
Topic: IO 520 Build on 12 foot Hamant
Replies: 21
Views: 1242

Re: IO 520 Build on 12 foot Hamant

Hardtail, Engine/prop trim and weight adjustments on an Airboat are the same as a kicker boat. Point the prop up (engine aft higher) and you lift the nose with more potential for hop. Point the prop down (engine aft down) and you push the nose down. Weight is the same, you would want to move weight ...
by Slidin Gator
Sun Jul 07, 2019 1:30 pm
Forum: Aircraft Power Only
Topic: IO 520 Build on 12 foot Hamant
Replies: 21
Views: 1242

Re: IO 520 Build on 12 foot Hamant

Hardtail,

No doubt you want to make sure the hull is true, but I assume that you looked into that during the build. Assuming hull is good, pitch the aft end of the engine down a bit and run it again.
by Slidin Gator
Sun Jul 07, 2019 1:25 pm
Forum: Airboat Tech
Topic: I'm Building 2 Stossel Boats with High Torque Motors
Replies: 63
Views: 3158

Re: I'm Building 2 Stossel Boats with High Torque Motors

Stripped the Polymer off hull #2 yesterday. This picture shows the bubble where the poly was pulling off the rivets. https://southernairboat.com/wp/wp-content/uploads/rtMedia/users/2619/2019/07/IMG_8971-600x800.jpg?1562519184 Found an easy way to remove the poly for sure, just stood on the hull and ...
by Slidin Gator
Fri Jul 05, 2019 8:44 pm
Forum: Airboat Talk
Topic: Running in salt water
Replies: 27
Views: 1648

Re: Running in salt water

So do they outlaw LCAC training at Parris Island?
by Slidin Gator
Wed Jul 03, 2019 7:54 pm
Forum: Automotive Power Only
Topic: LOW TORQUE LS Engine Build
Replies: 51
Views: 2803

Re: LOW TORQUE LS Engine Build

Interesting side note: torque and horsepower numbers always converge at 5252 RPM. Food for thought. No they don't, that only occurs when you plot Torque in Ft-lbf against Hp on the same scale. Plot them on different scales or try metric units and you can make them cross where ever you want. 5252 is...
by Slidin Gator
Wed Jul 03, 2019 3:00 pm
Forum: Automotive Power Only
Topic: LOW TORQUE LS Engine Build
Replies: 51
Views: 2803

Re: LOW TORQUE LS Engine Build

Interesting side note: torque and horsepower numbers always converge at 5252 RPM. Food for thought. No they don't, that only occurs when you plot Torque in Ft-lbf against Hp on the same scale. Plot them on different scales or try metric units and you can make them cross where ever you want. 5252 is...
by Slidin Gator
Tue Jul 02, 2019 8:59 pm
Forum: Aircraft Power Only
Topic: Mag timing for 87 octane
Replies: 15
Views: 539

Re: Mag timing for 87 octane

It seems like motor is just not running as smoothly as it should and seems to stumble more at top end of rpm Stumble or pre-ignition? Stumble is no ignition on a cylinder, it's a miss. Pre-ignition will be a popping sound from the exhaust. Either will result in loss of power at top end, pre-ignitio...
by Slidin Gator
Tue Jul 02, 2019 10:41 am
Forum: Aircraft Power Only
Topic: Mag timing for 87 octane
Replies: 15
Views: 539

Re: Mag timing for 87 octane

Do compression and leak down tests, sounds like you might have a cylinder gone bad. Also run a mag drop test to confirm both mags are kicking properly.

22 degrees BTDC would be the max timing I would run on CM fuel, but I run AV fuel. 87 octane is just asking for trouble, run premium at least.
by Slidin Gator
Wed Jun 26, 2019 9:50 pm
Forum: Airboat Tech
Topic: I'm Building 2 Stossel Boats with High Torque Motors
Replies: 63
Views: 3158

Re: I'm Building 2 Stossel Boats with High Torque Motors

lariat wrote:I really enjoy following along with this. Thanks for taking the time to share.

Thanks Lariat, I guess the time is spent better than talking to myself.
by Slidin Gator
Wed Jun 26, 2019 7:50 pm
Forum: Aircraft Power Only
Topic: Spark plug size ???
Replies: 1
Views: 115

Re: Spark plug size ???

18 mm spark plug threads. Note that I have found the spark plug base temp readings (using laser heat gun, not ring CHT) to be 50 to 100 Deg F less than the bayonet CHT's that Lycoming specifies.
by Slidin Gator
Mon Jun 24, 2019 9:33 pm
Forum: Airboat Tech
Topic: I'm Building 2 Stossel Boats with High Torque Motors
Replies: 63
Views: 3158

Re: I'm Building 2 Stossel Boats with High Torque Motors

Put the package into the old hull - Transport position. https://southernairboat.com/wp/wp-content/uploads/rtMedia/users/2619/2019/06/Motor-on-Old-Hull-800x600.jpg?1561425452 Here is the old seat stand. 126 lbs on the scale just in steel. The thing is definitely strong and rigid. I was constantly tig...
by Slidin Gator
Mon Jun 24, 2019 9:07 pm
Forum: Airboat Tech
Topic: I'm Building 2 Stossel Boats with High Torque Motors
Replies: 63
Views: 3158

Re: I'm Building 2 Stossel Boats with High Torque Motors

I zoomed in on the screen, and got 456 pounds. Yep, Rick is right! So I have gotten the Engine stand and fuel tank all repainted and received my new (used) engine mounts. On receipt I noticed that they had 7/16" bolts, the original equipment, vs the 1/2" bolts and mount holes on the engin...
by Slidin Gator
Sun Jun 23, 2019 12:02 am
Forum: Mini-Airboats
Topic: new guy here vw powered catamaran Mini
Replies: 19
Views: 547

Re: new guy here vw powered catamaran Mini

Watterbug wrote:[size=150]
The ultra prop cant go over 3100 rpm. All the VW guys tell me 3000 rpm mark is the sweet spot for HP on a standard 1600cc.

There’s your answer. I can’t help you with fitting prop to motor, but 3,000 rpm is the sweet spot for prop and motor it appears.
by Slidin Gator
Sat Jun 22, 2019 10:41 pm
Forum: Automotive Power Only
Topic: Manifold air speed
Replies: 17
Views: 576

Re: Manifold air speed

Now your using the old noodle, why would you put a 1000 CFM induction system on a 500 CFM application?

After you run it, tell the crowd about the difference in throttle response.
by Slidin Gator
Sat Jun 22, 2019 10:32 pm
Forum: Mini-Airboats
Topic: new guy here vw powered catamaran Mini
Replies: 19
Views: 547

Re: new guy here vw powered catamaran Mini

Dude, that's all I can think of, Dude. Please take this for what it is, constructive criticism. I'm trying to help you salvage your project and make something that will run. You went through all of that crap just to get a 21/19 = 1.1 gear reduction? Chain drive is just damn dangerous. When, not if, ...
by Slidin Gator
Sat Jun 22, 2019 6:26 pm
Forum: Mini-Airboats
Topic: new guy here vw powered catamaran Mini
Replies: 19
Views: 547

Re: new guy here vw powered catamaran Mini

But, before you go there, find out what you have will do. Move all the weight aft, pitch the prop up as much as possible and make sure you are getting all your power. What is the reduction ratio total and what RPM are you making on the motor? How much does the whole thing weigh? Length and Width? Wo...
by Slidin Gator
Sat Jun 22, 2019 2:07 pm
Forum: Mini-Airboats
Topic: new guy here vw powered catamaran Mini
Replies: 19
Views: 547

Re: new guy here vw powered catamaran Mini

You don't want a jon boat hull, they are too narrow. I have a hard time imagining what the value of a cat hull is unless you are building a 100+ mph boat and looking for lift. The cat hull has less water plane area, so it's gonna need more power than a flat hull to plane out, your primary issue is l...
by Slidin Gator
Fri Jun 21, 2019 10:32 pm
Forum: Mini-Airboats
Topic: new guy here vw powered catamaran Mini
Replies: 19
Views: 547

Re: new guy here vw powered catamaran Mini

Watterbug, Consider me mind blown :bom: I can explain your problem, but first please explain the build. What is the goal of the Cat style hull? I see a Utah style cage but no info on location. What are you trying to run that makes the Cat hull an advantage? I'm a dog guy so here is my logic. I'm thi...
by Slidin Gator
Fri Jun 21, 2019 10:18 pm
Forum: Airboat Talk
Topic: Gear Box or Not
Replies: 24
Views: 1377

Re: Gear Box or Not

I did a little reshuffling of priorities. I have a wide body 12 foot or so fiberglass boat that has a new rigging with a new 305 chevy small block that is stock and has poly on the bottom. I hope to run it where I wouldn't take my 16ft. I don't want to spend a lot of money on it for it is a second b...
by Slidin Gator
Tue Jun 18, 2019 9:44 pm
Forum: Airboat Tech
Topic: I'm Building 2 Stossel Boats with High Torque Motors
Replies: 63
Views: 3158

Re: I'm Building 2 Stossel Boats with High Torque Motors

Thanks BFC, that is useful information. Hopefully more folks will supply similar information for comparison.

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