Hymee Catback - Group buy
01-25-2004, 10:53 PM
#26
Kas,
When I do the mid-pipe it won't need the "fake" sensor, as we will re-use the existing rear O2 sensor. It will also have suitable a hi-performance cat in it, so it can be street legal.
I'm thinking about an optional resonator as well, just in-case folks think it is getting too loud.
Thanks for support on this guys. I'll send emails soon to all who have expressed interest. It will be great having our own home-grown exhaust. Just look at the problems/ mounting costs etc Wildcard faced.
Cheers,
Hymee.
When I do the mid-pipe it won't need the "fake" sensor, as we will re-use the existing rear O2 sensor. It will also have suitable a hi-performance cat in it, so it can be street legal.
I'm thinking about an optional resonator as well, just in-case folks think it is getting too loud.
Thanks for support on this guys. I'll send emails soon to all who have expressed interest. It will be great having our own home-grown exhaust. Just look at the problems/ mounting costs etc Wildcard faced.
Cheers,
Hymee.
02-01-2004, 01:05 AM
#29
HYMEE IN A PICKLE
Thanks all for your support on this so far.
I am in a bit of a bind, and need some input.
Firstly, I have modified the design so we don't need to replace the standard intermediate pipe (the last one before the muffler assy). It is 2.5" mandrel bent stainless steel. Most people wanted aluminised, and I couldn't see any point in taking a perfectly good stock pipe off, and replacing it with a 2.5" aluminised press bent pipe. Also, the best size for the mid-pipe & intermediate pipe has yet been determined. Perhaps we are going a bit too fast. The revised design I envisiged consisted of a flanged adaptor and would allow the use of the stock intermediate pipe, until such time as we know what the best size is for the "front" of the exhaust - when we go for headers. At that stage the stock intermediate pipe could be removed, and a new intermediate pipe/adaptor put in, leaving the "Hymee Muffler" assembly in place. It is dual 2.5 inch pipes, which is more than the cross sectional area of a single 3" pipe.
Secondly, I reviewed the responses to this thread. So far the tally looks like:
Aluminised - 4
Stainless - 2
Unsure - 1
Plus a US enquiry via PM, and a couple of enquiry's via Hymee mail. Also, one Mazda dealer seemed interested. That is not really a definate 10 though.
Thirdly, people want dyno results, and rightly so. I have not posted any yet until we are confident we have a repeatable, consistent way to bypass safe mode. We will be testing this tomorrow hopefully. But to be honest, the power gains in the "catback" section of the exhuast are marginal at best. The look and sound is the benefit. Experts I speak to seem to believe the real gains will come from the front of the exhaust - the headers and the mid-pipe. When you do change what is up front, you dont want the back to be the restriction. I believe the muffler assembly as pictured is about as least restrictive as one can go without using a straight peice of pipe, and keeping the noise to a acceptable level. Therefore the "Hymee rear mufflers" would compliment anything up-front.
My car is/was to have the new system installed Wednesday. We would then be taking the system off so we can make a jig, and "mass produce them" for you guys.
I have not asked for any deposits yet, 'cause I have not given a firm price, nor a got any quotes on shipping. But the price should not work out more than what I have indicated. In reality, I can't get firm numbers until I get deposits. Money talks.
I need to make a decision whether to proceed, but I hoping for input from the community that the decision affects - you.
Who is prepared to make a deposit, of say $100? If I only get 5 deposits, that will at least cover some costs, and help justify making a jig and the first small number.
Who thinks it is better to wait a while, and see what we learn from more exhaust development?
Who just wants a good system that sounds good for now, and trust it will complement the "front end" in the future?
Who thinks I should just cancel the whole thing for now?
I would appreciate your feedback.
Cheers,
Hymee.
I am in a bit of a bind, and need some input.
Firstly, I have modified the design so we don't need to replace the standard intermediate pipe (the last one before the muffler assy). It is 2.5" mandrel bent stainless steel. Most people wanted aluminised, and I couldn't see any point in taking a perfectly good stock pipe off, and replacing it with a 2.5" aluminised press bent pipe. Also, the best size for the mid-pipe & intermediate pipe has yet been determined. Perhaps we are going a bit too fast. The revised design I envisiged consisted of a flanged adaptor and would allow the use of the stock intermediate pipe, until such time as we know what the best size is for the "front" of the exhaust - when we go for headers. At that stage the stock intermediate pipe could be removed, and a new intermediate pipe/adaptor put in, leaving the "Hymee Muffler" assembly in place. It is dual 2.5 inch pipes, which is more than the cross sectional area of a single 3" pipe.
Secondly, I reviewed the responses to this thread. So far the tally looks like:
Aluminised - 4
Stainless - 2
Unsure - 1
Plus a US enquiry via PM, and a couple of enquiry's via Hymee mail. Also, one Mazda dealer seemed interested. That is not really a definate 10 though.
Thirdly, people want dyno results, and rightly so. I have not posted any yet until we are confident we have a repeatable, consistent way to bypass safe mode. We will be testing this tomorrow hopefully. But to be honest, the power gains in the "catback" section of the exhuast are marginal at best. The look and sound is the benefit. Experts I speak to seem to believe the real gains will come from the front of the exhaust - the headers and the mid-pipe. When you do change what is up front, you dont want the back to be the restriction. I believe the muffler assembly as pictured is about as least restrictive as one can go without using a straight peice of pipe, and keeping the noise to a acceptable level. Therefore the "Hymee rear mufflers" would compliment anything up-front.
My car is/was to have the new system installed Wednesday. We would then be taking the system off so we can make a jig, and "mass produce them" for you guys.
I have not asked for any deposits yet, 'cause I have not given a firm price, nor a got any quotes on shipping. But the price should not work out more than what I have indicated. In reality, I can't get firm numbers until I get deposits. Money talks.
I need to make a decision whether to proceed, but I hoping for input from the community that the decision affects - you.
Who is prepared to make a deposit, of say $100? If I only get 5 deposits, that will at least cover some costs, and help justify making a jig and the first small number.
Who thinks it is better to wait a while, and see what we learn from more exhaust development?
Who just wants a good system that sounds good for now, and trust it will complement the "front end" in the future?
Who thinks I should just cancel the whole thing for now?
I would appreciate your feedback.
Cheers,
Hymee.
02-01-2004, 01:22 AM
#30
trust me..this wont hurt
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I'm interested in the cat back, but have not voiced it yet. Hymee, as you have said, cat back power gains are minimal, it is the sound quality that counts. I drive a VERY LOUD MX5 as my daily driver, and it gets a bit much sometimes, the exhaust system was bought without hearing it. MY RX7 remains stock, the sound is pleasant as it is. The RX8 is too quiet. I had my partner overtake me last week on the way back from it's first service. There are no doubts it needs more dB out of the exhaust. My concern is I don't want to make it like my MX5. So I guess my order will have to wait until I can hear it.
Frustrating isn't it Hymee....
Frustrating isn't it Hymee....
02-01-2004, 05:22 AM
#32
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Hymee,
I am willing to pay the deposit up front if only to assist in furthering the whole exhaust development process. (Hey, it has to start from somewhere and I believe you are an essential person who can aid in the continual development process).
Yes, I would like to see further exhaust developments before changing my exhaust but if we all sit back and wait for money to fall out of the sky when we can be supporting a key person (Hymee) we could end up waiting a long time.
So for the sake of funding at least the initial Jig, count me in for an aluminised steel system.
Joe
I am willing to pay the deposit up front if only to assist in furthering the whole exhaust development process. (Hey, it has to start from somewhere and I believe you are an essential person who can aid in the continual development process).
Yes, I would like to see further exhaust developments before changing my exhaust but if we all sit back and wait for money to fall out of the sky when we can be supporting a key person (Hymee) we could end up waiting a long time.
So for the sake of funding at least the initial Jig, count me in for an aluminised steel system.
Joe
02-01-2004, 05:30 AM
#33
Joe,
Thanks for your public support.
And I must stress that I will only be "aiding" the development process. The actual work on that will be done by someone emminently more qualified to do that research and development than myself, with all the proper skills and resources at hand.
Perhaps if people are concerned about the outlay, we could all go for the aluminised system instead of the stainless - other than those who already trust me and have what it takes to go straight to stainless!
Such as Hymee Catback #001 himself - Mr. Wildcard :D
Cheers,
Hymee.
Thanks for your public support.
And I must stress that I will only be "aiding" the development process. The actual work on that will be done by someone emminently more qualified to do that research and development than myself, with all the proper skills and resources at hand.
Perhaps if people are concerned about the outlay, we could all go for the aluminised system instead of the stainless - other than those who already trust me and have what it takes to go straight to stainless!
Such as Hymee Catback #001 himself - Mr. Wildcard :DCheers,
Hymee.
02-01-2004, 05:31 AM
#34
trust me..this wont hurt
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Originally posted by pricer01
Did you say you were overtaken ........ SHAME SHAME SHAME!!!
Did you say you were overtaken ........ SHAME SHAME SHAME!!!
02-01-2004, 05:38 AM
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I fell victim to the same 'i wont drive it' trick. before investing in the RX8, I had a Mirage (Mitusbichi not Jet!) for commuting. It was a manual and my wife refused to drive it (manual hard on the knees ...) Somehow since the 8's arrival, the knee pain seems much less of an issue! GO FIGURE!?!?!?!?!?
02-01-2004, 05:40 AM
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Back on Topic ... Apologies Professor H.
I'm also a touch reluctant based mostly on my lack of understanding of the issues .. I too would be willing to contribute an early deposit if it helps the process
I'm also a touch reluctant based mostly on my lack of understanding of the issues .. I too would be willing to contribute an early deposit if it helps the process
02-01-2004, 05:43 AM
#37
trust me..this wont hurt
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My MX5 is not quite stock. VERY LOUD, very low, racing clutch which is extremely heavy, Koni's and Kmacs all the way round, and large sway bars front and rear, all adding up to a kidney jarring ride. It is very tiring driving it long distances. I can't blame her for not wanting to drive it, especially with the option of an RX8 and a series 7 RX7.
02-01-2004, 05:44 AM
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The reason I have chosen Steel is that Manufactures only started using Stainless when the warranty was incresed to 3 year 100/kms. In my experience, I have never kept a vehicle long enought to have the exhaust rust on me and I do not like the "tinny rattling sound" (exhaust gases "ping ponging" on the extremely smooth interior surface) which eminates from stainless steel exhaust pipes.
Hence, I cannot justify the additional cost of stainless on my RX-8 or any other previous cars that I have owned! (All previous cars have had exhaust modifications (at least 20 out of the 42 of them! - even my current Hilux 2.7 ute has a modified exhaust!).
Hence, I cannot justify the additional cost of stainless on my RX-8 or any other previous cars that I have owned! (All previous cars have had exhaust modifications (at least 20 out of the 42 of them! - even my current Hilux 2.7 ute has a modified exhaust!).
02-01-2004, 05:52 AM
#39
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what are the exact issues?
is the exhaust mandrel bent ? if its not then you'd need 3" to compensate for the restrictions around the bends. and then 3" gets louder.
making no more power? read around, you wouldnt be the first to make no more if not less power. Butt dyno's are nothing for me. I also feel that the louder sound creates a fasle sense of speed/power.
i'd be happy to pay a deposit, i know you and your work will be top notch and whatever you do is strictly for the benefit of rx8 drivers and developments.
On the other hand, do we all wait until the dyno issue is properly resolved and we have true numbers to work with?
As much as i want the sound a bit louder and more power, i'b be a bit dissapointed with an exhaust for show only. go before show.
still thinking.. at the same time, its only $450.
is the exhaust mandrel bent ? if its not then you'd need 3" to compensate for the restrictions around the bends. and then 3" gets louder.
making no more power? read around, you wouldnt be the first to make no more if not less power. Butt dyno's are nothing for me. I also feel that the louder sound creates a fasle sense of speed/power.
i'd be happy to pay a deposit, i know you and your work will be top notch and whatever you do is strictly for the benefit of rx8 drivers and developments.
On the other hand, do we all wait until the dyno issue is properly resolved and we have true numbers to work with?
As much as i want the sound a bit louder and more power, i'b be a bit dissapointed with an exhaust for show only. go before show.
still thinking.. at the same time, its only $450.
02-01-2004, 06:17 AM
#40
Joe,
My appologies - my "have what is takes" remark was not pointed at you or anyone else. I for one have never had a stainless system on any of my cars. And the system I get for the jig will be aluminised.
Kas,
The intermediate pipe is now going to be the stock mandrel bent pipe, at 2.5" (full reasons as per the earlier posting).
The stock tailpipes are 2.25" from memory, and the new ones are 2.5". 2.5" will be adequate for even if development dictates a 3" mid and intermediate pipe - 2 x 2.5" pipes have heaps more cross-sectional area than a single 3" pipe. And the mufflers have an internal 2.5" mandrel bent perforated pipe.
As for power etc, I am under no illusions. Testing will tell. This is just one component of a complete exhaust. Traditionally power comes from up front, and the note from down the back. Some people might just want the note and the tuff looking tips. Some might want to take it to the next step. So this caters for whatever people choose, hopefully.
Remember all the drooling over the Borla. How much was it going to cost Wildcard to land one here - $1500! He is wrapped with what we did for him, and I bet him and his wallet are glad.
Anyway - I'm glad I have sparked a bit more interest. Otherwise Wildcard might end up with the only "Hymee Catback" on earth! That will truly be clasified as a Hymee Special!
Cheers,
Hymee.
My appologies - my "have what is takes" remark was not pointed at you or anyone else. I for one have never had a stainless system on any of my cars. And the system I get for the jig will be aluminised.
Kas,
The intermediate pipe is now going to be the stock mandrel bent pipe, at 2.5" (full reasons as per the earlier posting).
The stock tailpipes are 2.25" from memory, and the new ones are 2.5". 2.5" will be adequate for even if development dictates a 3" mid and intermediate pipe - 2 x 2.5" pipes have heaps more cross-sectional area than a single 3" pipe. And the mufflers have an internal 2.5" mandrel bent perforated pipe.
As for power etc, I am under no illusions. Testing will tell. This is just one component of a complete exhaust. Traditionally power comes from up front, and the note from down the back. Some people might just want the note and the tuff looking tips. Some might want to take it to the next step. So this caters for whatever people choose, hopefully.
Remember all the drooling over the Borla. How much was it going to cost Wildcard to land one here - $1500! He is wrapped with what we did for him, and I bet him and his wallet are glad.
Anyway - I'm glad I have sparked a bit more interest. Otherwise Wildcard might end up with the only "Hymee Catback" on earth! That will truly be clasified as a Hymee Special!
Cheers,
Hymee.
02-01-2004, 05:21 PM
#42
To save posting my account details directly on the forum, please send an HymeEmail to hymee@hymee.com and I will reply with the details for exhaust deposits.
Cheers,
Hymee.
Cheers,
Hymee.
02-03-2004, 06:46 AM
#44
The "master" will be made tomorrow, thanks mainly to some faithfull supporters willing to pay a deposit. Thanks jax8 and NT Rotor Head! You will be the very first 2!
Tonight I did 4 runs with my MR Dyno. The average of the 4 runs is posted here. The ambient temp was 21-22 deg. C.
Interestingly, I am down about 10kW from my last testing with L&L. Also, my car was on the Dyno yesterday to test "Safe Mode" things, and it consistently pulled 180HP at the wheels, which is about 140kW. That is consistent with the MR Dyno I published in my report on initial stage 1 testing.
(More on this safe mode thing in another thread, I'll post in Tech Garage. We did about 16 runs, and it consistently laid down this curve. Absolutley consistently.)
So where is 10kW? I don't know... I refueled this morning, the road was slightly wet (very slightly), I entered the wrong weight (1445kg tonight), different day, HIGH HUMIDITY <---- they might all add up. Anyway, I'll do another after the cat-back (not expecting anything really), and also do a proper dyno in more controlled conditions, and post the results.
Cheers,
Hymee
Tonight I did 4 runs with my MR Dyno. The average of the 4 runs is posted here. The ambient temp was 21-22 deg. C.
Interestingly, I am down about 10kW from my last testing with L&L. Also, my car was on the Dyno yesterday to test "Safe Mode" things, and it consistently pulled 180HP at the wheels, which is about 140kW. That is consistent with the MR Dyno I published in my report on initial stage 1 testing.
(More on this safe mode thing in another thread, I'll post in Tech Garage. We did about 16 runs, and it consistently laid down this curve. Absolutley consistently.)
So where is 10kW? I don't know... I refueled this morning, the road was slightly wet (very slightly), I entered the wrong weight (1445kg tonight), different day, HIGH HUMIDITY <---- they might all add up. Anyway, I'll do another after the cat-back (not expecting anything really), and also do a proper dyno in more controlled conditions, and post the results.
Cheers,
Hymee
02-03-2004, 05:33 PM
#47
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Well its coming with the car along with different rims.
its got most of the accessories such as side skirts front air dam etc...
with leather pack $60000
secondhand
15000kms on it
i thought it was a fair deal
$2300 on transfer fees then off i go
its got most of the accessories such as side skirts front air dam etc...
with leather pack $60000
secondhand
15000kms on it
i thought it was a fair deal
$2300 on transfer fees then off i go
02-04-2004, 12:45 AM
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Sounds like good buying, Ageo. Let us know what exhaust is fitted after you take delivery.
Where will the car be living? (Some of you guys are very cagey about giving any personal info in your profile.)
Welcome,jack
Where will the car be living? (Some of you guys are very cagey about giving any personal info in your profile.)
Welcome,jack
02-04-2004, 01:48 AM
#49
Slightly back on topic...
The "Master" has been built with the new design, and it is on my car for a few days, then we take it off to get a jig made of it. That will happen over the next week or so, and then the first orders can be filled.
The new design allows the use of the existing "intermediate pipe". It is 2.5" (actually 63.5mm) mandrel bent stainless steel from the factory, and I was not comfortable replacing it with a press bent 2.5" pipe. The muffler assembly is as per the pictures posted of Wildcard's prototype. There is a new adaptor peice, which is a short, straight length of 2.5" pipe that has a bolt-up flange on the rear end to connect to the muffler assembly, and a U-bolted slip joint to connect to the rear end of the intermediate pipe. The slip joint uses the factory U-Bolt. The short adaptor pipe permits the replacement of the intermediate pipe at a future date with a larger one if research and development deems this necessary, while being able to re-use the muffler assembly.
We did some work to "thicken" up the ends of the tips. Very subtle though. Sorry L&L - you can't get truncated rolled ends in Stainless, but chrome is OK.
Pricing has been finalised. (Hooray!)
Stainless Steel System $750 + shipping
Consisting of:
1 x Stainless Steel 2.5" flanged adaptor pipe.
2 x Polished Stainless Steel mufflers. Double wrapped and TIG welded. Mandrel bent internal 2.5" tubing.
1 x Stainless Steel Y piece, 2.5" Outlets, Mandrel Bent and flanged front end.
2 x 2.5" Stainless Steel Tail Pipes.
2 x 4" Stainless Steel Tips, Double Wall, truncated ("Magna-flow" style, as per the photo's)
1 x flange gasket
Nuts/bolts/washers/spring washers for flange joint.
Mild Steel / Aluminised System $450 + shipping
Consisting of:
1 x Aluminised Mild Steel 2.5" flanged adaptor pipe.
2 x Aluminised Mild Steel mufflers. Double wrapped. Mandrel bent internal 2.5" tubing.
1 x Mild Steel Y piece, 2.5" Outlets, Mandrel Bent and flanged front end.
2 x 2.5" Aluminised Mild Steel Tail Pipes.
2 x 4" Stainless Steel Tips, Double Wall, truncated ("Magna-flow" style, as per the photo's)
1 x flange gasket
Nuts/bolts/washers/spring washers for flange joint.
Here is a couple of photos of it on my (unwashed
) car:
Looks tuff. Sounds nice, no drone, all what has been said before.
It also passed the noise meter test. It was 86 - 88dB at 6000RPM (3/4 RPM of Max Power). The limit is 90dB.
Cheers,
Hymee.
The "Master" has been built with the new design, and it is on my car for a few days, then we take it off to get a jig made of it. That will happen over the next week or so, and then the first orders can be filled.
The new design allows the use of the existing "intermediate pipe". It is 2.5" (actually 63.5mm) mandrel bent stainless steel from the factory, and I was not comfortable replacing it with a press bent 2.5" pipe. The muffler assembly is as per the pictures posted of Wildcard's prototype. There is a new adaptor peice, which is a short, straight length of 2.5" pipe that has a bolt-up flange on the rear end to connect to the muffler assembly, and a U-bolted slip joint to connect to the rear end of the intermediate pipe. The slip joint uses the factory U-Bolt. The short adaptor pipe permits the replacement of the intermediate pipe at a future date with a larger one if research and development deems this necessary, while being able to re-use the muffler assembly.
We did some work to "thicken" up the ends of the tips. Very subtle though. Sorry L&L - you can't get truncated rolled ends in Stainless, but chrome is OK.
Pricing has been finalised. (Hooray!)
Stainless Steel System $750 + shipping
Consisting of:
1 x Stainless Steel 2.5" flanged adaptor pipe.
2 x Polished Stainless Steel mufflers. Double wrapped and TIG welded. Mandrel bent internal 2.5" tubing.
1 x Stainless Steel Y piece, 2.5" Outlets, Mandrel Bent and flanged front end.
2 x 2.5" Stainless Steel Tail Pipes.
2 x 4" Stainless Steel Tips, Double Wall, truncated ("Magna-flow" style, as per the photo's)
1 x flange gasket
Nuts/bolts/washers/spring washers for flange joint.
Mild Steel / Aluminised System $450 + shipping
Consisting of:
1 x Aluminised Mild Steel 2.5" flanged adaptor pipe.
2 x Aluminised Mild Steel mufflers. Double wrapped. Mandrel bent internal 2.5" tubing.
1 x Mild Steel Y piece, 2.5" Outlets, Mandrel Bent and flanged front end.
2 x 2.5" Aluminised Mild Steel Tail Pipes.
2 x 4" Stainless Steel Tips, Double Wall, truncated ("Magna-flow" style, as per the photo's)
1 x flange gasket
Nuts/bolts/washers/spring washers for flange joint.
Here is a couple of photos of it on my (unwashed
) car:Looks tuff. Sounds nice, no drone, all what has been said before.
It also passed the noise meter test. It was 86 - 88dB at 6000RPM (3/4 RPM of Max Power). The limit is 90dB.
Cheers,
Hymee.
02-04-2004, 04:20 AM
#50
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Hymee
Could you please explain?
As your new designed exhaust system uses the existing stock standard "intermediate pipe". How come considering that there seems to be a lot less materials and labour involved in this new design. However the price is the same as your first design where the intermediate pipe was totally changed.
Surley using the stock standard intermediate pipe and not replacing it should have lowered the price of the new designed exhaust not kept it at the same price as before?
Cheers
Michael
Could you please explain?
As your new designed exhaust system uses the existing stock standard "intermediate pipe". How come considering that there seems to be a lot less materials and labour involved in this new design. However the price is the same as your first design where the intermediate pipe was totally changed.
Surley using the stock standard intermediate pipe and not replacing it should have lowered the price of the new designed exhaust not kept it at the same price as before?
Cheers
Michael