NW IMAC Competition Thread

[harv]

	Quote: Originally Posted by Azhar
	From what I understand, you dad had the header at 14" with almost no gap between the header and pipe. The sweet spot is between 14.5 and 15".

i got the proof cause i got those pipes. hahaha. not that its a big deal, im going to stretch the gap to one inch on each pipe to see what happens.

[danielph]

I'm with ya' Harv. If you get the length right, it's a sweet power setup!

[rcgood]

	Quote: Originally Posted by Azhar
	Actually the "jump" is less noticeable if the length of the header is set at 14.5 - 15". You lose a little top end but that transitional jump is not enough to be noticeable.

The pipes on the 170 produce the most power at about 12". Yes you do have insane power but pretty much an on/off switch on the throttle. Take your pick: idle or full throttle. At 15" length you do lose MOST of the power the pipes put out not just a little top end. And even there you don't have the midrange you usually have with cans or mufflers. I looked into this subject a lot because I was considering that setup (43% Carden/170 with pipes) myself. And Henry was one of the people I talked to as well and like Miranda said he pretty much reinforced what I said. Here I know two people personally that actually have 2 43% Cardens. One with 170 and the other with 200. For this reason I decided to go with a 40% on 170/cans or even 150 if it's light enough for my IMAC plane. It's personal preference too. If you fly lower classes IMAC or just 3D you don't need the extra power. Just my humble opinion

[rcgood]

	Quote: Originally Posted by mirandapiorun
	and guys dad was actually talking to me the other day, about the 170. He did say it's mid range was terrible... But anything else was great! Ben was actually spot on from what dad has told me...

Miranda when are you gonna take this knowledge and use it for your own flying? I thought you'll be doing basic in Molalla

	Quote: Originally Posted by Rainman
	Ben, sounds like I stand corrected about the engine differences. You are amazing man. Not only are you smart but when I saw how much your flying had progressed this year in Molalla, I was completely blown away! You are an excellent representation to what one can achieve when they really pour themselves passionately into this hobby. I am sorry I didn't video you flying the yak. I hope you fly Freestyle in Molalla next season. I would love to see you duking it out with all the exceptional talent in the NW. Doesn't matter where you live Ben, you will always be a part of us here. I look forward to flying with you again soon.

Mike thanks and I'm glad you're back in it...already . Glad to hear you found work that's always good. I agree with you that NW IMAC has a very good group of people and I did feel right at home when I visited this summer. Next time I'll try to bring some warmth with me though. I did not feel too cozy with the 50 degree weather in July/Aug

[Mike Williams]

	Quote: Originally Posted by rcgood
	Next time I'll try to bring some warmth with me though. I did not feel too cozy with the 50 degree weather in July/Aug

haha

[borealnw]

Most know I've been to "DA" school dealing with the new 120. That said I've been talking with Jeff and Tony at DA. Here are some things I picked up along the way.

If you have no mid range it could be as simple as Servo geometry. yeah yeah I know but it is very important on the newer carbs. Here is how to check it and set it up. With the throttle at half on the TX the servo arm "1" is at 90* in travel. Another word straight at a 90 along the top edge of the servo box. OK now check the throttle linkage arm on the carb. Even though the arm is bent 30* or so the original arm on the carb should sit at half straight up along the center of the jug. If not adjust mechanically until it is. Then in the TX your end points should be exactly the same for all the way closed throttle and all the way open. On my TX I have it set up so that on each end point is 89 of a total 100 on both ends. I took some time to get it right but my low to mid range flat spot is gone. The throttle response is completely linear all the way up and down.

Second I agree that changing the pipe distance forward or back makes a huge difference on the power band. I would call DA and ask Curtis to help in the distance issue. Another thing I found in talking with him is, the nylon tube used to join the pipes together is not intended to be used as an extension. The distance between them is 1/8" to allow for clearance of the pipes from hitting one another. If the distance is any greater then there is a Strong chance of it burning through as carbon builds on the walls. That said for $3.00 you can purchase an extension from DA along with a stick of solder to weld it on with a torch. I have a spare set if anyone needs a them.

One last thing extentions on the back side of a can or pipe is not a good idea if you are seeking rpm on the top end. The 2" extentions I had on mine limited the high end 400 RPM. With the Extentions I was getting 5780 without 6190.

Mike I am thrilled you will be back flying it would not be the same without you. I've enjoyed our talks and time together you've taught me allot this year not only about IMAC but life in general. I dig how you see things in life anyway I am glad you will return.

[Azhar]

Ben,

There was a long test done about getting the right header length for the RE3s on the 170. The "14.5-15" " numbers came out of those tests. Talking to a few different people running this setup seems to confirm this. I will see how mine performs and post it here.

	Quote: Originally Posted by rcgood
	The pipes on the 170 produce the most power at about 12". Yes you do have insane power but pretty much an on/off switch on the throttle. Take your pick: idle or full throttle. At 15" length you do lose MOST of the power the pipes put out not just a little top end. And even there you don't have the midrange you usually have with cans or mufflers. I looked into this subject a lot because I was considering that setup (43% Carden/170 with pipes) myself. And Henry was one of the people I talked to as well and like Miranda said he pretty much reinforced what I said. Here I know two people personally that actually have 2 43% Cardens. One with 170 and the other with 200. For this reason I decided to go with a 40% on 170/cans or even 150 if it's light enough for my IMAC plane. It's personal preference too. If you fly lower classes IMAC or just 3D you don't need the extra power. Just my humble opinion

[mirandapiorun]

	Quote: Originally Posted by rcgood
	The pipes on the 170 produce the most power at about 12". Yes you do have insane power but pretty much an on/off switch on the throttle. Take your pick: idle or full throttle. At 15" length you do lose MOST of the power the pipes put out not just a little top end. And even there you don't have the midrange you usually have with cans or mufflers. I looked into this subject a lot because I was considering that setup (43% Carden/170 with pipes) myself. And Henry was one of the people I talked to as well and like Miranda said he pretty much reinforced what I said. Here I know two people personally that actually have 2 43% Cardens. One with 170 and the other with 200. For this reason I decided to go with a 40% on 170/cans or even 150 if it's light enough for my IMAC plane. It's personal preference too. If you fly lower classes IMAC or just 3D you don't need the extra power. Just my humble opinion

Yeah Ben, dad said your spot on; right on the money. lol

	Quote: Originally Posted by rcgood
	Miranda when are you gonna take this knowledge and use it for your own flying? I thought you'll be doing basic in Molalla I did not feel too cozy with the 50 degree weather in July/Aug

I know... I know... But ugh... Dad is buyin me a 50cc cub. LOL! its gunna be pree cool! lol.. I know i've said this about like 20 billion katrillion times, but I'm really gunna try and get the courage to fly.......... infront of people.... lol

Oh and please doo!!! we could really use some warmth... hahaha

[Bad Dog!]

Check this out.
http://www.flyinggiants.com/forums/s...ad.php?t=45848

and

http://www.flyinggiants.com/forums/s...=52373&page=15

and

http://www.flyinggiants.com/forums/s...ad.php?t=55218

[Rainman]

	Quote: Originally Posted by mirandapiorun
	Yeah Ben, dad said your spot on; right on the money. lol I know... I know... But ugh... Dad is buyin me a 50cc cub. LOL! its gunna be pree cool! lol.. I know i've said this about like 20 billion katrillion times, but I'm really gunna try and get the courage to fly.......... infront of people.... lol Oh and please doo!!! we could really use some warmth... hahaha

We'll all be rootin for you girl... Peeerfect plane for you to start with.

[Bad Dog!]

More good RE3 info.

http://www.flyinggiants.com/forums/s...ad.php?t=37742

[mirandapiorun]

	Quote: Originally Posted by Rainman
	We'll all be rootin for you girl... Peeerfect plane for you to start with.

Lol thank you! I thought it was kinda cheesey!! Hahaha

[skagitrat]

Question here, do any of you use throttle curves to help smooth out the throttle response on your engine? My engine is almost at full throttle at a few clilcks above 1/2 stick movement. I've got equal travel on the servo arm both ways. So would you find your idle rpm then top end, split the difference and set 50% at that rpm on the throttle curve? Just want to find the right way to do this or if I have to do it at all.

Thanks,

Carl

[danielph]

That is what everyones arguing about right now! lol Personally I just deal with it. My DA-120 on pipes is a little peaky, but I can get used to it very fast. Running a curve is not a bad idea for some though.

[wmat7039]

	Quote: Originally Posted by skagitrat
	Question here, do any of you use throttle curves to help smooth out the throttle response on your engine? My engine is almost at full throttle at a few clilcks above 1/2 stick movement. I've got equal travel on the servo arm both ways. So would you find your idle rpm then top end, split the difference and set 50% at that rpm on the throttle curve? Just want to find the right way to do this or if I have to do it at all. Thanks, Carl

Hi Carl.... Since I don't want to offend anyone...I won't say anything regarding the throttle transition that my DA 170 with KS Tuned Pipes has.

"With that being said"....One has to realize that one has to tune the engine properly after breaking in, rather than leaving it at factory settings. The KS 1090 pipes are definitely different than the MTW RE3 pipes..... AND BOTH are a step forward and above the Greves pipes.

In addition to the selection of which set of tuned pipes to use, one has to also spend some time dialing in a throttle curve to get the feel to where a pilot wants it. It really does not happen magically.

To answer your question, I DO think using the curve WILL make a significant difference in how the throttle responds. Here is a photo of the curve in my 12X which is being used on the DA 170 & KS 1090 tuned pipes. On rolling circles, throttle inputs are extremely important if a pilot wants to maintain a certain speed into & with the wind....so a "notch" on the throttle stick should make a difference either way. BTW... I did get the ratchet put in by JR on the 12X....It's harder to fly IMAC with a throttle stick that has no ratchet.
regards,
Wayne