Exhaust upgrade

[cub_driver]

I have been told I could increase my 0320s horsepower by 13 horses if I upgraded my exhaust from stock. What are the pros and cons of the different manufatures? If I upgraded my engine to 160 hp and then added one of the new exhaust systems would I still get another 13 horses?

Cub_Driver

 

[Crash]

Exhaust

You are proble refering to the Leading Edge Exhaust. I know a A&P that has installed 3 - 4 on different PA-18's. Said he flew them before and after and maybe at best could see 25 rpm gain on one. Some guys swear by them. At $3,000.00 and 8 lbs heavier then a stock system, I'll pass. One of my friends put one on his 180hp Cub and said he didn't notice a bit of gain over the stock exhaust. The jury is still out in my neck of the woods on this. Crash

 

[cub_driver]

Wow 3000 bucks to gain eight pounds guess I won't be running out to buy a new system any time soon. I am still running the original generator and starter seems like upgrading those might be a better investment what do you think? Who makes the best upgrades

cub_driver

 

[cubdriver]

Some of us are already running heavy duty exhaust systems by Dodge and others. That would make the weight gain only about 4 pounds.

Based on the Lycoming tests, these 4 pounds equal about 15 HP. Probably the cheapest and lightest "bolt on power" you can get.

PS - They are not approved for the 160 hp yet but I am told that 160 hp testing is in progress.

 

[T.J.]

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[murph]

TJ:
Can you personally verify the power gain with the LE system? If so, can you quantify the gain, horsepower, rpm, etc.?
Thanks,
murph

 

[T.J.]

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[StewartB]

Isn't that why they claim "recovers horsepower" instead of makes horsepower? I have three friends that have the Leading edge system on Cubs. Two guides, and one weekend warrior. All three LOVE it. No hesitation in their endorsement. Another friend has one on his 206. Same thing. Absolute praise. Is it perfectly legal on the Cubs? They don't care. It certainly isn't dangerous.
SB

 

[cubdriver]

Ther manufacturer makes no claims but Lycoming tested the exhaust and found that it increased horse power dramatically. I can't remember all the data but I believe it is posted somewhere on this site, try a search.

 

[TIM AYERS]

everybody needs to go back thru HOTRODING 101, The first place to look for power gaines is the intake and exhast area. Hooker Headers and Edelbrock manifolds.........( now if I could just figure out how to install this 3 duce set up)

 

[FlipFlop]

Ther manufacturer makes no claims but Lycoming tested the exhaust and found that it increased horse power dramatically. I can't remember all the data but I believe it is posted somewhere on this site, try a search.

Was that Lycoming or Ly-Con?... Big difference...

 

[Raymond Blerot]

I believe that I may have had one of the first sets of ehaust from leading edge for a 180 cub, I have seen a small increase in rpm ,say 30, however it has been on now for 200 hrs and not one problem ,also it is extemely easy to remove and I have not had any cracks that used to frequent my exhaust system since this instalation. This,in my opinion,is the best system so far and I believe that Dane has a very good product that he can be proud of.Keep smiling,Ray Blerot

 

[arcticace]

I spoke with the guys at powerflow systems last month about a tuned exhaust for the PA-18. While they didn't give me a date or anything this project is on their "to do" list. I have one of their systems on my 172 and I am impressed. I get an extra 90 RPM static, noticable increase in climb performance and 4-5 knots faster cruise. As an added bonus it makes a really cool sound. 8)

http://www.powerflowsystems.com/

There is a bit of discussion on this subject in the Leading Edge Exhaust thread in Supercub Gatherings

 

[cubdriver]

Leading Edge Exhaust

I just recieved word yesterday that all the testing has been completed for the 160 HP STC and the documentation has been submitted to the FAA.

Approval is expected shortly.

 

[Cub Kid]

Another friend has one on his 206. Same thing. Absolute praise. Is it perfectly legal on the Cubs? They don't care. It certainly isn't dangerous.
SB

I too run Leading Edge Exhaust Systems on my 206G, and am quite impressed with them...doesn't make the 206 a performer (will always be a dog, unless I had the money for one of those 350 horse upgrades), but it certainly makes a difference. I have not flown the 206 since september, so can't quote any RPM difference, but you certainly feel it with a load.

Bill

 

[AkPA/18]

Hi Arcticace---I must be missing something here. How did you increase cruise with your hp increase. You do have a fixed pitch?? Thanks.

 

[AkPA/18]

Arcticace----thanks for the link. I went to the site and read the owners comments. Quite a few owners were calling in increased cruise also. Still don't quite understand the whole picture if they are flying the same fixed pitch at the same rpm.

in edit: and same density alt

 

[cubdriver]

Jerry explained it like this in the Brackett filter Thread, I think the same principal would apply to exhaust backpressure. He knows his stuff.

Yes it seems strange. A light load of NOX is a good example. It will pull 20 to 25 lbs harder at the same RPM. It burns longer and creates more pressure on the piston when the crank is in a better position to use it. Dosen't change the HP that much, but the torque goes outta sight. The lack of foam in the aircleaner shell seems to change the mixture just enough to cause a slight change in torque also. The numbers listed are index marks and have no set value except in relation to each other. The change is small but it is there. As a result of this test, I pull the foam just before I compete. It's all the little things that count. Jerry.

 

[cubdriver]

I just talked to Dane Sr. at Born To Preform and he says the FAA has just revised his STC to include the 160 HP Cubs.

Bolt them on boys and girls.

 

[T.J.]

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[AKCub]

I just finished the install of the leading edge system on my cub with a 160 and an 82-44 borer and I went from 2320 to 2410 plus. (it's hard to say exactly but it's not quite 100rpm and not really 90rpm)
I haven't had a chance to do anything with it but a runup to look for leaks and fly it from merrill back down to lake hood. When I get home i will post more info.
I will also be weighing my old system- it was a mix of Atlee dodge and univair to see what the difference in weight really is between the two systems. At least for my plane.
more info then
Scott

 

[diggler]

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[T.J.]

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[diggler]

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[T.J.]

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[Jerry Burr]

Exhaust.

As long as both banks feed into opposite ends of the same muffler, there isn't going to be much change in flow no matter what shape the primaries are in. If you just want more room next to the cowl,( which is what it says) then it's a good deal. I learned a little trick last year at a sales seminar. Just because the brand name says WEIGHT WATCHERS, dosen't mean it has anything to do with calories. It's just the name of the company. Jerry.

 

[Crash]

I just couldn't see $1,795.00 for the Cub Crafters stacks on my 180hp conversion over a new set of Airframes Inc stacks for around $800.00. Cub Crafters just prices itself out of the market with its greed. I was talking with Nathen Richmond at the Airshow last year and asked him about the new stacks and any performance gains. He said "they hadn't seen any, mainly they fit under the cowl better". I guess they found some improvement in performance gains since then.....humm Crash

 

[irishfield]

I guess they found some improvement in performance gains since then.....humm Crash

The guy flying the airplane probably just got more proficient!! :lol:

Wayne

 

[Steve's Aircraft (Steve)]

I have been reading these post and it seems everyone is interested in hrsp gain by numbers i.e. 13 etc. Actually guys, none of the exhaust mods will make your engine produce more hrsp., such as 150 to 163 for instance. A Lycoming engine is rated at 150 hrsp at a specific rpm and manifold pressure, and with a fixed pitch you can possibly change the rpm, but not the manifold pressure. This relates to another term "torque". What the exhaust systems mod does is decreases the back pressure, allowing the manifold pressure to increase therfore increasing the available " torque", not hrsp. This means when you haul back on the stick and point the cubs nose up you can maintain the rpm at a higher angle of attack because you have more available, useful torque to hold it there. I messed around with my cubs exhaust back in the 70's and gained 200 rpm static. That is a lot of gain of lost hrsp/torque over the stock system, and the cub flew like it, however the FAA at the time wasn't too interested in helping out, so I dropped it.
Steve

 

[diggler]

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