My car is at the shop for Supersprint headers and race pipe install

**MPILOT** · 03-26-2003, 10:40 PM

I can't wait to drive the car tomorrow.

My baseline HP before the install this afternoon showed 273.5 HP on the dyno jet. Thats with MK-Motorsport muffler and S.S. X-Pipe. I think my car should have a little over 275 cause my spark plugs could be bad at 31k miles with my driving.

Evosport showed me a Dyno reading for an E39 M5 that had 310 HP with the old OEM plugs and it made over 330 HP after the tune up and new plugs.

Keep posted I'll post the results tomorrow

**JMWeb** · 03-26-2003, 11:23 PM

Good to hear that your car is getting modded up

I have 2 questions:

1. What is the race pipe? Dont you already have the x-pipe?
2. Are you also installing catalyst? In the post you just mentioned the headers. Just wondering if there is a way around the CEL.

**MPILOT** · 03-27-2003, 12:23 AM

Yes I have the x-pipe which replaces the rear resonator.

Now I'm installing the Supersprint headers and race pipe which eliminates the cats.

This is the new race pipe which has the post cat placement for the O2 Sensors.

Its really cool they are positioned at an angle as far as possible from the primary flow to where they get less exhaust flow than the first O2 sensors, which means they get a smaller voltage reading resulting in no check engine light and no ECU problems.

**Sticky** · 03-27-2003, 01:25 AM

Sweet! No check engine lights and no ecu problems? I will have to do this same mod.

**BMWguy206** · 03-27-2003, 01:42 AM

Its really cool they are positioned at an angle as far as possible from the primary flow to where they get less exhaust flow than the first O2 sensors, which means they get a smaller voltage reading resulting in no check engine light and no ECU problems.

I'm confused here. Does the exhaust system come with any catalysts at all? If it doesnt, then it will set a check engine light.

**MPILOT** · 03-27-2003, 03:02 AM

The Supersprint headers come without cats.

There is a pre cat O2 sensor mounting point welded on the headers.

After that the US Spec M3 has its first resonator on the left and a straight pipe on the right of the front pipe section. Here the Euro M3 has its Cats. Supersprint sell either metallic racing cats (100cpi) or a race pipe which has no cats.

The Race pipe has the post cat O2 sensor point welded in at an angle of about 25 degrees from the pipe. This allows less flow from the headers to hit the O2 sensor resistor. So this records a lower voltage reading than the upstream O2 sensor which keeps the check engine light from coming on, simulating the flow as if it was effectively decreased if there was a restricting cat.

Here's a link of US Header/cat vs Euro comparison

http://www.bimmerforums.com/forum/sh...threadid=55313

Heres the Euro headers and Euro cats

http://www.bimmerforums.com/forum/sh...threadid=82408

Supersprint Headers

http://bmpdesign.com/exhaust/bmw/pro...22787/501L.gif

Supersprint Cats

Supersprint Race Pipe
I can't find pictures of these, but you can check out more info on bmpdesign or evosport

http://www.evosport.com/product/exha...rsprint_header

Supersprint X-pipe

http://bmpdesign.com/exhaust/bmw/pro...22787/513L.gif

**JMWeb** · 03-27-2003, 10:55 AM

So there is no need to get the AA O2 Simulators?

**BMWguy206** · 03-27-2003, 11:54 AM

I dont think the current O2 sims out there work on the DME S52 engine management system. Someone else on this forum can give you more info. on it since I got it from him.

**Hellabad** · 03-27-2003, 01:47 PM

No one who knows me could accuse me of always being legal (I am moral however), but I don't like to run without cats.
It is a Federal offense, of course, but to me, the challenge is in beating the BMW engineers at their own game.
If I get more hp, but don't pass smog, then what have I done that is imaginative?

here are two reasons why I have legal (but not stock, there is a loophole) Cats on my e46M3:

1) The big one, car makes the same or perhaps MORE hp with cats. (Dyno proven, aftermarket software)
2) Another big one: I know a person, firsthand who wrecked his truck. Truck had no cats. Insurance investigator looked at it at the wrecking yard, and upon discovering it had no cats, did not pay the claim based on the fact that the truck was not legal to drive on a public road. This poor guy had to make payments for 3 more years with nothing to show for it.
PS. I have no intent to argue about the dyno claim, I am not at liberty to say who or when, but it is a trusted source that is good enough for ME to base my decision on.
Jay

**mpowerme** · 03-27-2003, 10:20 PM

Let us know the noise level without cats.

**tlaselva** · 03-27-2003, 11:03 PM

Originally posted by Hellabad
1) The big one, car makes the same or perhaps MORE hp with cats. (Dyno proven, aftermarket software)

I've seen dyno runs on cars showing that it comes to a point where less backpressure causes a loss of mid and high end torque, with minor, and at times loss of high end HP.

Low restriction cats, yes, but removing them all together, with a low restriction muffler may cause a detrimental effect on HP.

Guess when you run her on the dyno we'll know for sure.

**stevemedina** · 03-28-2003, 01:39 AM

mpilot....can you do me a favor...if you can...

could you please take some pics of how they wire the 02 sensors....are they splicing the wires...or are they installing a new harness....thx.

**MPILOT** · 03-28-2003, 01:39 AM

I'm planning to add some free flowing metallic cats in a couple of month. MK-Motorsport is releasing their race cats soon. It'll be nice to compare dyno runs with race pipe vs cats.

**stevemedina** · 03-28-2003, 01:44 AM

Who's doing the install anyway?...

**MPILOT** · 03-28-2003, 02:13 AM

EvoSport are doing everything upto the dyno

The new harness would be too costly so they spliced the O2 sensor wires. I'll take as many pictures as I can from underneath the car as well as in the engine bay before the heat shield is installed.

I will also post dyno results as well as video and sound clips.

**stevemedina** · 03-28-2003, 02:21 AM

excellent thanks....

**DriveBy** · 03-28-2003, 07:06 AM

I am working backwards.

Last part I replaced was the SS midpipe. I would recommend it. Good bang for the buck.

**KJM3** · 03-28-2003, 01:24 PM

Originally posted by MPILOT
EvoSport are doing everything upto the dyno

The new harness would be too costly so they spliced the O2 sensor wires. I'll take as many pictures as I can from underneath the car as well as in the engine bay before the heat shield is installed.

I will also post dyno results as well as video and sound clips.

When will you post all this info? I'm VERY interested to see your results!!!

**s4play** · 03-28-2003, 06:57 PM

I'm very impressed by your dedication to get this stuff working. I know it isn't very cheap to do the mods you're doing. Evosport is a good place to chose for the work that's for sure.

Are you going to be at BimmerFest this year? I will be with the SPP guys but would love to chat with you more and also hear your car and compare results.

I have a Supersprint resonator by-pass pipe and have been working on a custom muffler of my own testing different flow rates and chamber designs. Seems like every aftermarket muffer has some good and bad points.

Please keep me updated on your testing!

late,
rick

**Jet** · 03-28-2003, 08:05 PM

I'd like to hear results as well

**MPILOT** · 03-29-2003, 07:29 AM

I have driven Euro E46 M3s, they pull harder than the US cars with their wider torque curve from down low. Everyone complains about the US headers and those big restricting cats that are stuck to the primaries of the stock header all the way upstream.

BUT there is nothing like the Supersprint headers and race pipe setup, the M3 is now an angry monster that easily gets pissed off!!!

First of all I have to say the sound is crazzzy!!!

Make sure to keep in 3rd or 4th with easy revs when passing cops.

I will post my dyno results on Monday as I'm waiting for another dyno run on Monday afternoon after installing the irridium spark plugs. My baseline dyno run showed good power till about 7,200 RPM where the power curve starts to level and slightly drop with alot of noise in the power curve. There was 2 misfires past 7,200 RPM on the dyno. I think BMWs advice on adding 1 liter of oil every 1,500 miles isn't a good idea cause that new oil that mixes with the older oil foul your plugs early.

Well the results with the old plugs, 32k hard driven miles, showed 289 wheel HP and about 24.4 HP and 18 lb-ft gain at the wheel at 7,600 RPM. I'm hoping for around 300 HP at the wheel with the irridium plugs, almost 360 HP at the crank.

The runs were performed on 4th gear, 3rd gear runs would be too unstable on the dyno with more loss of traction. I would love to know my 3rd gear power curve as I also installed EvoSport pulleys, power steering/alternator/water pump, which show most gains in the 1st 3 gears and about 3 HP at the wheel on 4th upwards.

There is no loss at any RPM, power gains are great over 5,000 RPM. The sound again is like nothing, nothing, nothing else.

**sgalaba** · 03-29-2003, 10:18 AM

Here is my dyno run that can be used for comparison, hope it helps. 309 at the rear wheels, 375 crank. Items installed: Euro Headers, no cat (O2 sensors attached to stock US pipe before Connector pipe, no errors run this way, interesting about the 'angle'), SS connector pipe, EH muffler, Schrick Cams (which add about 8-10hp). Dyno runs were done on 93 gas, stock plugs with about 12000 miles on both engine and plugs.

**sgalaba** · 03-29-2003, 10:39 AM

FWIW...
The run I posted was done in 5th gear, which is the 1 to 1 ratio. The 1:1 ratio is the normal gear that runs are pulled on, the results from pulls in gears other than the 1:1 can be misleading and should be corrected / adjusted for in the dyno software, if not the results will be a bit off (the dyno software needs to be told that you are running a 1:1.23 gear ratio). Since you started in 4th gear you should finish your testing in 4th gear and then find a dyno that can handle the M3's top speed, handle the 1:1 ratio.

**JMWeb** · 03-29-2003, 11:46 AM

How did you fix the CEL sgalaba? No 02 simulators just a different placement?

**Hellabad** · 03-29-2003, 12:41 PM

"I've seen dyno runs on cars showing that it comes to a point where less backpressure causes a loss of mid and high end torque, with minor, and at times loss of high end HP."

If any car makes more hp with more backpressure, that means the cam timing is wrong. E46M3 is vanos, constantly variable cam timing. I'm really starting to think that even less backpressure is absolutely the only improvement to M3 exhaust.
That is why I have an exhaust that is 100% straight through, twin 60mm minimum, all the way out. It really seems to work.

http://www.ground-control.com/e46_m3_muffler.htm

Thread: My car is at the shop for Supersprint headers and race pipe install

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My car is at the shop for Supersprint headers and race pipe install

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