Likes Likes:  0
Page 1 of 9 123 ... LastLast
Results 1 to 40 of 340

Thread: Exhaust upgrade

  1. #1

    Join Date
    Jan 2003
    Location
    Big Lake AK
    Posts
    790
    Post Thanks / Like

    Exhaust upgrade

    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

  2. #2
    Crash's Avatar
    Join Date
    Apr 2002
    Location
    Nikiski Alaska
    Posts
    2,695
    Post Thanks / Like

    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
    Thanks boarfish thanked for this post

  3. #3

    Join Date
    Jan 2003
    Location
    Big Lake AK
    Posts
    790
    Post Thanks / Like
    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

  4. #4

    Join Date
    Aug 2002
    Location
    Oklahoma
    Posts
    174
    Post Thanks / Like
    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.

  5. #5
    T.J.'s Avatar
    Join Date
    Apr 2002
    Location
    Alaska
    Posts
    3,211
    Post Thanks / Like
    delete

  6. #6
    murph's Avatar
    Join Date
    Jun 2002
    Location
    Rotan, TX.
    Posts
    494
    Post Thanks / Like
    TJ:
    Can you personally verify the power gain with the LE system? If so, can you quantify the gain, horsepower, rpm, etc.?
    Thanks,
    murph

  7. #7
    T.J.'s Avatar
    Join Date
    Apr 2002
    Location
    Alaska
    Posts
    3,211
    Post Thanks / Like
    delete

  8. #8
    StewartB
    Guest
    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

  9. #9

    Join Date
    Aug 2002
    Location
    Oklahoma
    Posts
    174
    Post Thanks / Like
    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.

  10. #10

    Join Date
    Nov 2002
    Location
    GLENDALE AZ
    Posts
    60
    Post Thanks / Like
    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)

  11. #11
    FlipFlop's Avatar
    Join Date
    Sep 2002
    Location
    Maintaining at Flight Level Zero, requesting lower...
    Posts
    1,483
    Post Thanks / Like
    Quote Originally Posted by 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.
    Was that Lycoming or Ly-Con?... Big difference...
    ô¿ô Ladies And Gentlemen, Cuby (et al) Has Left The Hangar...

  12. #12

    Join Date
    Feb 2003
    Posts
    19
    Post Thanks / Like
    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

  13. #13
    arcticace's Avatar
    Join Date
    Jan 2003
    Location
    Fort Simpson, NT Canada
    Posts
    19
    Post Thanks / Like
    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.

    http://www.powerflowsystems.com/

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

  14. #14

    Join Date
    Aug 2002
    Location
    Oklahoma
    Posts
    174
    Post Thanks / Like

    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.

  15. #15
    Cub Kid's Avatar
    Join Date
    Feb 2003
    Location
    Nome, AK
    Posts
    386
    Post Thanks / Like
    Quote Originally Posted by stewartb
    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

  16. #16
    AkPA/18's Avatar
    Join Date
    Feb 2003
    Location
    Big Lake Ak
    Posts
    746
    Post Thanks / Like
    Hi Arcticace---I must be missing something here. How did you increase cruise with your hp increase. You do have a fixed pitch?? Thanks.

  17. #17
    AkPA/18's Avatar
    Join Date
    Feb 2003
    Location
    Big Lake Ak
    Posts
    746
    Post Thanks / Like
    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

  18. #18

    Join Date
    Aug 2002
    Location
    Oklahoma
    Posts
    174
    Post Thanks / Like
    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.

  19. #19

    Join Date
    Aug 2002
    Location
    Oklahoma
    Posts
    174
    Post Thanks / Like
    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.

  20. #20
    T.J.'s Avatar
    Join Date
    Apr 2002
    Location
    Alaska
    Posts
    3,211
    Post Thanks / Like
    delete

  21. #21
    AKCub's Avatar
    Join Date
    May 2002
    Location
    Anchorage, Alaska
    Posts
    92
    Post Thanks / Like
    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

  22. #22

    Join Date
    Jun 2002
    Posts
    1,343
    Post Thanks / Like
    delete

  23. #23
    T.J.'s Avatar
    Join Date
    Apr 2002
    Location
    Alaska
    Posts
    3,211
    Post Thanks / Like
    delete

  24. #24

    Join Date
    Jun 2002
    Posts
    1,343
    Post Thanks / Like
    delete

  25. #25
    T.J.'s Avatar
    Join Date
    Apr 2002
    Location
    Alaska
    Posts
    3,211
    Post Thanks / Like
    delete

  26. #26
    Jerry Burr's Avatar
    Join Date
    May 2002
    Location
    Sedro Woolley, Washington.
    Posts
    715
    Post Thanks / Like

    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.

  27. #27
    Crash's Avatar
    Join Date
    Apr 2002
    Location
    Nikiski Alaska
    Posts
    2,695
    Post Thanks / Like
    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

  28. #28
    irishfield's Avatar
    Join Date
    Feb 2003
    Location
    Penetanguishene, Ontario Canada
    Posts
    3,021
    Post Thanks / Like
    Quote Originally Posted by Crash
    I guess they found some improvement in performance gains since then.....humm Crash
    The guy flying the airplane probably just got more proficient!!

    Wayne

  29. #29
    Steve's Aircraft (Steve)'s Avatar
    Join Date
    Aug 2002
    Location
    White City Oregon
    Posts
    233
    Post Thanks / Like
    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

  30. #30

    Join Date
    Jun 2002
    Posts
    1,343
    Post Thanks / Like
    deleet

  31. #31
    Jerry Burr's Avatar
    Join Date
    May 2002
    Location
    Sedro Woolley, Washington.
    Posts
    715
    Post Thanks / Like

    Hp/Torque.

    Hi Steve. I'm sorry but I don't agree with your theory at all. To keep it short, I will say it this way. The Continental O-200 was certified by the factory as 100 HP. That was with 4 inch straight exhaust stacks. When Piper added their exhaust system to the engine it lost around 10HP. If you put the straight stacks back on the engine it will again produce 100 HORSEPOWER at 2750 rpm. Peak torque is far below that rpm. Jerry.

  32. #32

    Join Date
    Feb 2003
    Location
    KHRR
    Posts
    159
    Post Thanks / Like
    Jerry, could you be a little more specific about "peak torqe" What cam do you use in the 0200?

    Does the leading edge exhaust feed both "banks " into the oposite sides of the muffler? I kinda get the impression from you that these new exhaust systems aint that great.

  33. #33
    Steve's Aircraft (Steve)'s Avatar
    Join Date
    Aug 2002
    Location
    White City Oregon
    Posts
    233
    Post Thanks / Like
    Jerry,
    You are correct in that the manufactures specify a particular hrsp at a specific rpm. That will not change at that rpm. However most engines will not produce rated hrsp (rpm) because of the exhaust system. Any improvement in flow through the exhaust will allow more rpm to regain the lost hrsp. As to the torqe (manifold pressure) the constant speed prop guys have the advantage in the gov. flattens the prop to reach rated rpm, but with a poor flowing exhaust system the available torque is lower and the prop pitch will increase only so much and still maintain rpm. With a good flowing exhaust, the manifold pressure increases allowing a higher pitch to the prop to maintain rated rpm. That is why those guys seem to get better performance increases with the improved system over the fixed pitch.
    As for what I did on my Cub, I converted the inside of the muffler to flow like a glass pack muffler used on the hot rods. The current exhaust muffler is highly restrictive in it's design and a straight through flow made a big difference on the Lyc 290D2. It also lost 15 degrees average oil temp. The problem I ran into was the cost of testing equipment the FAA wanted me to have to prove the system. Couldn't afford it then.
    Steve

  34. #34
    Jerry Burr's Avatar
    Join Date
    May 2002
    Location
    Sedro Woolley, Washington.
    Posts
    715
    Post Thanks / Like

    Hp / Torque.

    Hi Steve. OK, so much for keeping it short. We can look at the engine as a type of air pump. If we limit the escape of exhaust gas during the exhaust stroke, there will be an increase in residual pressure left in the cylinder when the intake valve opens. ( this also retains additional heat in the engine ) Therefore the intake stroke will not be able to create as much vacuum ie; causing a reduction in manifold pressure. Well and fine. The problem that I have is if this is more detrimental to torque or HP. We know that we will arrive at peak torque at a much lower rpm than peak HP. I don?t have the manual handy but let?s say that peak torque is 2100 rpm. We are pumping 2931 cu ft of air through our pump. At peak HP, or 2750 rpm we are pumping 3838 cu ft of air. I submit that any restriction in the airflow on the intake side ( dirty air cleaner ) or the exhaust side ( Piper exhaust system ) is going to be exponently more detrimental at the higher airflow.
    When we were testing our four into one exhaust system, there was no (visible on our MP gage ) change in MP. There was however increased rpm ( time ) , increased thrust ( force ) which computed onto a 9 hp ( corrected for ambient conditions ) increase over the stock system.
    Cobblemaster. I am not experimental. I have to keep a stock cam. Jerry.

  35. #35
    arcticace's Avatar
    Join Date
    Jan 2003
    Location
    Fort Simpson, NT Canada
    Posts
    19
    Post Thanks / Like
    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,
    I think you are right. Jerry's NOS example would apply to a dyno or a CS prop. A fixed pitch prop will produce the same amount of thrust at a set RPM and airspeed no matter what is turning it (rubber bands ). My cruise speed figures were at 8000' DA and full throttle. All other factors were the same for both flights. Sorry I should have stated that more clearly.

  36. #36
    Jerry Burr's Avatar
    Join Date
    May 2002
    Location
    Sedro Woolley, Washington.
    Posts
    715
    Post Thanks / Like

    Thrust - RPM

    Hi Artic Ace. I do not agree with your statement, ( A fixed pitch prop will produce the same thrust as long as the RPM remains constant). If you add either alcohol or NOX to an engine the thrust (torque) will increase and the RPM can remain constant. It has to do with the modified burning rate (cylinder pressure) on the burning (power stroke) of the cycle. It burns longer and therefore holds higher pressure longer on the power stroke allowing better angle on the crankshaft for a longer time. Which is why (at night) you see more flame coming out the stack of an alky burner than a gasser. Jerry.

  37. #37

    Join Date
    Feb 2003
    Location
    KHRR
    Posts
    159
    Post Thanks / Like
    Jerry, I was just wondering if you had the cam that C90s used to have that are no longer available. Somebody told me they had more torqe or power or something like that.

  38. #38
    Jerry Burr's Avatar
    Join Date
    May 2002
    Location
    Sedro Woolley, Washington.
    Posts
    715
    Post Thanks / Like

    Cam.

    Hi Cobblemaster. The C-90 cam has more overlap than the O-200 cam and works very well in the O-200. There are several flying in Waynes neck of the woods. Just have to use them Exp. Jerry

  39. #39
    arcticace's Avatar
    Join Date
    Jan 2003
    Location
    Fort Simpson, NT Canada
    Posts
    19
    Post Thanks / Like
    Hi Jerry,

    I see that you are equating thrust and torque. When I used the term "thrust" I was refering to what the propeller delivered to the airframe. If you mean thrust with reference to the piston acting on the crankshaft I will have to scratch my head a bit longer before I really understand.
    Perhaps these things we can agree on--Torque times RPM is proportional to power and increased power applied to a fixed pitch propeller will increase it's RPM. Then you will have to agree with my statement. If not please explain. Glen

  40. #40
    Jerry Burr's Avatar
    Join Date
    May 2002
    Location
    Sedro Woolley, Washington.
    Posts
    715
    Post Thanks / Like

    Power/torque/hp.

    Hi Articace. We still don't agree yet I'm afraid. Power (HP) is force times distance divided by time. Torque as such dosen't have an entry point. Let's try this. If you take an engine and run it flat out. It will have a peak HP and peak torque. If you reduce the bore and increase the stroke of the engine and re-run it, it will repeat the previous results except the torque rating will be higher. Cyl pressure on the extended crank throw for a longer time. Diesel vs Gas, same thing. Longer burn more torque same horsepower. So you can say that by adding NOX we are (chemically stroking ) the engine by creating a longer burn. If you really push the NOX it will affect everything, including gobs of horsepower. I am talking light loads. I guess I have gotten off subject. Bottom line is almost any free flowing exhaust will perform better than Piper's stock setup. A 4 into one will create a much better performing engine, at only a slight increase in noise. Not having a dyno, and needing comparisons, we tie the tail down and take thrust readings. Correct it for air density and that is what we go by. To do a worthwhile comparison in the air, you need (still) air. Then you have to run both systems (propellers or what ever ) at a constant pressure altitude, constant MP, constant weight, and then correct for temp. In testing 4 propellers it's a lot faster to do it on the ground. When talking to Continental about their correction factors, they just laughed. They simply take the test cell to sea level pressure and temp. They don't have to correct anything. Must be nice. Jerry.

Similar Threads

  1. C65 to C90 Upgrade
    By Lost Coast in forum Cafe Supercub
    Replies: 3
    Last Post: 11-24-2004, 11:10 PM
  2. ANOTHER exhaust/muffler change/upgrade.
    By Longwinglover in forum Modifications
    Replies: 8
    Last Post: 02-17-2004, 04:01 AM

Tags for this Thread

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •