Got to prototype some exhaust..
Got to prototype some exhaust..
Well as the topic says, I got the privelage of being a tester for the new Knife exhaust system. When I was approached with the idea and concept, I jumped at the chance. The Knife exhaust is a full 3" stainless 304 dump-back exhaust system focused on sound and performance in addition to being relatively inexpensive. Also, Knife really focuses on making sure that the exhaust will be complete and they ship all their systems with EVERYTHING you need to make it run right which includes an o2 sensor setup to prevent a CEL while driving with the test pipe in. So without further ado.. here are some pics of when it showed up and went on the car. This is the first in the country and I was just lucky to have the chance 
Off the car:
On the car out the axle-back section:
Other on car pics:
Tried to take a pic of the welds.. but apparently I'm horrible with a digital camera. They look like machine welds. I'll have to ask to make sure but they are damn perfect.
Another prototype to drool over but not related. Complete titanium exhaust (not just muffler) 4 inch v-band setup for a supra.. mwaahahaha
In the picture you see I put it on originally with the cat and drove it like that for a day, but I decided to go ahead and put the test pipe on the next day. Its a pretty noticeable difference with just the downpipe and catback, but with the testpipe, the butt dyno reads pretty good numbers. The turbo of course spools up much quicker for better throttle response and the mid and upper range is greatly extended. Soundwise, even with the test pipe in the exhaust never has a raspy note to it. At WOT in boost it begins to get what I can only describe as a slight spura-ish edgey sound. I have a video clip I made on my digi cam but it sounds nothing like it.. so maybe some vid to come if I can find a camera..
The exhaust went on without a hitch and fits perfectly which I thought was impressive for never having test fitted the setup before. As you can see, everything is very well made and assembled and even the polishers seemed to take pride in their work. Good stuff with a good sound. Now onto more details and some dyno numbers.. next post..
Off the car:
On the car out the axle-back section:
Other on car pics:
Tried to take a pic of the welds.. but apparently I'm horrible with a digital camera. They look like machine welds. I'll have to ask to make sure but they are damn perfect.
Another prototype to drool over but not related. Complete titanium exhaust (not just muffler) 4 inch v-band setup for a supra.. mwaahahaha
In the picture you see I put it on originally with the cat and drove it like that for a day, but I decided to go ahead and put the test pipe on the next day. Its a pretty noticeable difference with just the downpipe and catback, but with the testpipe, the butt dyno reads pretty good numbers. The turbo of course spools up much quicker for better throttle response and the mid and upper range is greatly extended. Soundwise, even with the test pipe in the exhaust never has a raspy note to it. At WOT in boost it begins to get what I can only describe as a slight spura-ish edgey sound. I have a video clip I made on my digi cam but it sounds nothing like it.. so maybe some vid to come if I can find a camera..
The exhaust went on without a hitch and fits perfectly which I thought was impressive for never having test fitted the setup before. As you can see, everything is very well made and assembled and even the polishers seemed to take pride in their work. Good stuff with a good sound. Now onto more details and some dyno numbers.. next post..
So I drove the system around for a couple of weeks just to make sure things were cool and everything has been awesome. I also own a Xede setup so I downloaded the 0+ map and the car really felt like it woke up quite a bit. It seemed to be hard to get dyno time nailed down so I worked with the manufacturer on a couple of things that I think would be neat and all of which made it to the final design I'll get to the extras in a minute.. Well we finally made it to the dyno today.. I live in Austin Texas so it was a nice sticky 90 or so today and we hit the dyno to see what kind of gains the exhaust would make.
I really didn't think it was fair to people who drove their cars every day to give them HP numbers of a car that had been iced down or had any special prep, fuel, or anytyhing else done to it. So I drove the car "spirited" for a bit, then showed up and put it basically straight onto the dyno. I had hoped to dyno in Houston on a dynojet, but we ended up going locally on a mustang dyno notorious for shooting out low numbers. Someone who is much more familiar with dynos can probably give a more accurate description as to why this is, but basically its because the dyno applies load to the vehicle as opposed to a dynojet which only applies the weight of the drum. Anyways, the gain is whats important. With the xede 0+ map and exhaust (no tuning whatsoever) and everything else factory including plugs and shell 93 octane gas the car put down 235hp and 226 torque. We figured we might as well go backwards since the exhaust and xede were already on the car. We then made a couple of pulls on the ecu without the xede tune and put down 211hp and 219 torque. This gave us our baseline numbers for stock ecu w/exhaust numbers and we jumped off the dyno to put the stock exhaust back on.
On a side note, with the exhaust completely assembled, this swap took just about 20 minutes! We went back to the dyno (once again not giving the car a chance to cool down to make things even) and the only thing performed before the pulls was a reset of the ecu to give it a better chance of adjusting to the change back. With the stock exhaust and stock ecu on the car, it put down 190hp and 202 tq consistently and we called it a day. I have all the sheets and I'll post parts of them as I get them scanned in (hp scanjet is sooooooo slow).
Heres the break down of the numbers for ya:
Stock Ecu and Stock Exhaust VS Stock Ecu and Knife Exhaust
That means the exhaust alone (and not even factoring the ecu reset to close the gap) netted 21.7 whp and 17.4 torque.
The full dyno is here:
http://www.prebmw.com/ex/no-xede.jpg
Next is Stock Exhaust Stock Ecu VS Xede and Knife Exhaust
Full Dyno:
http://www.prebmw.com/ex/xede.jpg
This is what really made me smile here. With the exhaust and a base map downloaded straight off the website the car netted 45.1 whp!! and the same 17.4 torque (it was getting a bit hotter outside and thats all I can figure besides a basemap tune just not being that accurate).
Ok.. if you ahve read this far.. then on to the goodies that I managed to get in there for the real evo serious people out there. First off, the sale version will include a flex pipe section to take strain off the turbine housing when the exhaust moves and resist stress cracks. Also, the sale version will include a second o2 bung pre-welded into the downpipe (plugged of course) for those of us who want to slap a wideband on it easily at some point. The system ALSO includes an o2 mod to prevent the CEL normally associated with a test pipe and all the stainless hardware you need to match the set. Good stuff! Should be released pretty soon on the market.. If people are interested, I'll get more info on that for ya
I'll get to the extras in a minute.. Well we finally made it to the dyno today.. I live in Austin Texas so it was a nice sticky 90 or so today and we hit the dyno to see what kind of gains the exhaust would make.I really didn't think it was fair to people who drove their cars every day to give them HP numbers of a car that had been iced down or had any special prep, fuel, or anytyhing else done to it. So I drove the car "spirited" for a bit, then showed up and put it basically straight onto the dyno. I had hoped to dyno in Houston on a dynojet, but we ended up going locally on a mustang dyno notorious for shooting out low numbers. Someone who is much more familiar with dynos can probably give a more accurate description as to why this is, but basically its because the dyno applies load to the vehicle as opposed to a dynojet which only applies the weight of the drum. Anyways, the gain is whats important. With the xede 0+ map and exhaust (no tuning whatsoever) and everything else factory including plugs and shell 93 octane gas the car put down 235hp and 226 torque. We figured we might as well go backwards since the exhaust and xede were already on the car. We then made a couple of pulls on the ecu without the xede tune and put down 211hp and 219 torque. This gave us our baseline numbers for stock ecu w/exhaust numbers and we jumped off the dyno to put the stock exhaust back on.
On a side note, with the exhaust completely assembled, this swap took just about 20 minutes! We went back to the dyno (once again not giving the car a chance to cool down to make things even) and the only thing performed before the pulls was a reset of the ecu to give it a better chance of adjusting to the change back. With the stock exhaust and stock ecu on the car, it put down 190hp and 202 tq consistently and we called it a day. I have all the sheets and I'll post parts of them as I get them scanned in (hp scanjet is sooooooo slow).
Heres the break down of the numbers for ya:
Stock Ecu and Stock Exhaust VS Stock Ecu and Knife Exhaust
That means the exhaust alone (and not even factoring the ecu reset to close the gap) netted 21.7 whp and 17.4 torque.
The full dyno is here:
http://www.prebmw.com/ex/no-xede.jpg
Next is Stock Exhaust Stock Ecu VS Xede and Knife Exhaust
Full Dyno:
http://www.prebmw.com/ex/xede.jpg
This is what really made me smile here. With the exhaust and a base map downloaded straight off the website the car netted 45.1 whp!! and the same 17.4 torque (it was getting a bit hotter outside and thats all I can figure besides a basemap tune just not being that accurate).
Ok.. if you ahve read this far.. then on to the goodies that I managed to get in there for the real evo serious people out there. First off, the sale version will include a flex pipe section to take strain off the turbine housing when the exhaust moves and resist stress cracks. Also, the sale version will include a second o2 bung pre-welded into the downpipe (plugged of course) for those of us who want to slap a wideband on it easily at some point. The system ALSO includes an o2 mod to prevent the CEL normally associated with a test pipe and all the stainless hardware you need to match the set. Good stuff! Should be released pretty soon on the market.. If people are interested, I'll get more info on that for ya
Last edited by MayhemSi; Aug 14, 2004 at 11:53 PM.
Originally Posted by JustDSM
Does it clear the tie bars?
The whole idea is to offer a COMPLETE dumpback setup. Everything will be included to get things running well, with no check engine lights, and without losing anything on the evo. The problem is simply that true 3" pipe like you see there is just physically too big to fit there, clear the tiebars, and still maintain fluid flow and not rattle. The front tie bar will work when the package ships to your door.
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The tip lines up in the middle of the hole in the back and the canister is angled slightly towards the side of the car (straightest path for the exhaust to exit) I'll try to snap a pic tonight for ya. I have no idea why I didn't even think to take one.. lol.
Pricing has been set. The introductory price for te first 20 complete setups will be 899 and I am hoping to setup a group buy for evom peeps at 850 shipped to your door. I am hoping to be able to show good interest from the board here and convince him to hook us up a bit. MSRP will be closer to 1000 (same quality and more complete kit then the vishnu which costs like 1200+ I believe? not too sure on how he figured it).
Pricing has been set. The introductory price for te first 20 complete setups will be 899 and I am hoping to setup a group buy for evom peeps at 850 shipped to your door. I am hoping to be able to show good interest from the board here and convince him to hook us up a bit. MSRP will be closer to 1000 (same quality and more complete kit then the vishnu which costs like 1200+ I believe? not too sure on how he figured it).
Also a quick note. The test pipe is not pictured above but it is the same pipe quality, finish, and style and flanged to let you swap in the stock cat when you need to go visit the government or something.. hehe
Just an update for all the people that have been sending me PMs. I can't answer quite as many as you guys send per day, so the news is this. Everything is ready to roll. New pricing is 850 shipped complete with no minumum amount to get reserved to get this price. PM me for info if you are interested.