Thinking about doing xpipe.

Well, im just thinking about go straight or xpipe... i have a 645 with k&n air filter and oem M6 mufflers. I just want F1 sound (similar M6 sound) but i dont know what resonator i have to remove... the twin resonators or the center resonators(box)...what is better to go on f1 sound? what is better, xpipe or straight pipe. i want to know if the gas consumption will be high. ..what do you think about my questions???......yorgi. i know you are the master here....hahaha. Thanks.

I have spoke with multiple factories and exhaust professionals over the subject, when I was designing the prototype, and specifically how to make this car sound it's best, that is how I came to my exhaust setup.

One: It will NEVER sound like a M6, much less a F1 car. The OEM M6 mufflers don't make the sound of that engine, it's the high-revving V10 that does.

Two: You will want to remove all 4 resonators... straight pipes will make a deeper note, which is not what you bor any 6er owner seem to be after.

Three: Place the x-pipe as far forward as you can for a "higher-revving" sound, I'd also recommend a x-pipe that has a laddered diameter, if I have mine manufactured I will be selling the laddered to give better sound, increased flow, and increased power.

Once again, it will not sound like a high-revving V10, and the resonator delete/x-pipe will not increase sound volume/tone much at all, you have to swap mufflers for that, and I'd say for what you are going for OEM M6 mufflers aren't the way to go.

The prototype mufflers the factory and I ended up having created, were actually designed for a M6(2.5") and I had the shop used the increased diameter piping for a few feet, at the recommendation of the exhaust designer, for optimal sound and performance.

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Originally Posted by JPEG23

It will never sound like a M6, much less a F1 car M6 mufflers don't make the sound of that engine, it's the high-revving V10 that does.

All of this has been covered multiple times. You will want to remove all 4 resonators... straight pipes will be a deep note, place the x-pipe as far forward as you can for a "higher-revving, " sound.

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Thank you JPE. i know it will never sound like F1, it was just a comment. i like how your car sounds. i think i will go straight pipes and all for resonators removed... Thanks.

Originally Posted by albertoxikitin

Thank you JPE. i know it will never sound like F1, it was just a comment. i like how your car sounds. i think i will go straight pipes and all for resonators removed... Thanks.

I modified my response, to reflect my full thoughts.

If you want a sound like mine, I may recommend holding off, I am almost certain I will have my mufflers and x-pipe placed into a limited production run to start it out and see how it goes, if it goes well, I would of course continue production. If I do the limited production run, I will become a forum sponsor to sell it to members, at a discount of course.

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Originally Posted by JPEG23

I modified my response, to reflect my full thoughts.

If you want a sound like mine, I may recommend holding off, I am almost certain I will have my mufflers and x-pipe placed into a limited production run to start it out and see how it goes, if it goes well, I would of course continue production. If I do the limited production run, I will become a forum sponsor to sell it to members, at a discount of course.

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Can you post some pics of your xpipes and mufflers??? It wil be great

Originally Posted by albertoxikitin

Can you post some pics of your xpipes and mufflers??? It wil be great

Will do, give me a day or two.

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I was also thinking of changing my stock 645 ci exhaust for a OEM M6 exhaust I picked up for 200 last week...I was wondering besides modifying my bumper or replace it with a used M6 bumper.
Does the rest of the muffer fit perfectly? M6 exhaust is from 2008 and my 645 CI convertible is 2005 ? Thanks.

What is the best Xpipe on the market? The Supersprint seems a bit unreasonable for me. Any suggestion ? I don't some low quality either.

Originally Posted by Drunken Monk

I was also thinking of changing my stock 645 ci exhaust for a OEM M6 exhaust I picked up for 200 last week...I was wondering besides modifying my bumper or replace it with a used M6 bumper.
Does the rest of the muffer fit perfectly? M6 exhaust is from 2008 and my 645 CI convertible is 2005 ? Thanks.

As some of the studs in this forum pointed out in previous threads, the pipes for the M6 are longer and without changing the rear bumper, it will stick out several inches longer. I seen it... It looks like ****.

Originally Posted by reytran

What is the best Xpipe on the market? The Supersprint seems a bit unreasonable for me. Any suggestion ? I don't some low quality either.

I am not quite sure how much ultimate quality is a big factor? Unless it is a stepped pipe like Jpeg had mentioned manufacturing. Most of the custom fab ones at a local muffler shop are just standard exhaust pipe metal.

Adding the X-Pipe is not your end-game here, the real thing people are doing is removing the Resonator's to give better free-flow and increasing the exhaust note. However, when you remove just the resonators and have two straight pipes going back you get droning sounds at cruising speed, so the X-Pipe is put in to fix that from happening.

There are guys that have bought a simple universal X-Pipe from Summit Racing for $30 so that they could remove the Resonator.

Perhaps some of our car experts can chime in with some opinions...

Here is a previous post I did on x-pipe advantages. The main purpose of the x-pipe is to cause a plunging effect to prevent back-pressure. It also helps prevent droning/rasp.

My muffler shop made a custom x-pipe out of SS pipe. Cherry Bomb makes a very nice aluminized steel x-pipe or you can also use the Magnaflow SS piece for ~ $50.

Thanks for all the advise.

So this is really good route so far to go. I'm planning on getting eisenmann muffler later when I'm done with the M6 conversion.

But which one have better quality do you know? I checked online and find out the Magnaflow cost 91.87 for almost all sites. The Cherry Bomb is $50.

Originally Posted by Yorgi

Here is a previous post I did on x-pipe advantages. The main purpose of the x-pipe is to cause a plunging effect to prevent back-pressure. It also helps prevent droning/rasp.

My muffler shop made a custom x-pipe out of SS pipe. Cherry Bomb makes a very nice aluminized steel x-pipe or you can also use the Magnaflow SS piece for ~ $50.

I just have another question that how is that possible to install the X-pipe to the back, isn't the pipe setup is similar to this Supersprint Xpipe.

http://www.supersprintna.com/product...arch_model/287

Here is a little primer on exhaust metals:

The best exhausts material is stainless steel (which is what the OEM 6er pipes are made of). It is expensive but lasts the life of the car and never rusts. Up near the engine, exhaust pipes are glowing red hot and you want SS in this area because the heat increases the likelihood of rust when metal is exposed to moisture.

Next best is aluminized steel which is a steel/aluminum alloy and lasts a long time but will eventually corrode and fail. It costs about half of what SS goes for.

The lowest quality is coated mild steel. This is crap and will only last a few years.

The OEM pipes are 2.25" stainless steel so I would stick to that material. It's not cheap but it will never rust. Plus it s a very good idea to use the same type of steel when ever you connect two metal objects. When two different metals touch you get corrosion.

The stainless steel one by Mangna flow is better. Here is a stainless version by SummitRacing that goes for $70 if you want to save a few $. I do not like the looks of the $30 Summit Racing x-pipe since it requires the muffler shop to add 4 elbows (one to each end of the X) to make it work.

With all the pictures people have posted of their setups I've seen a few where the shop used aluminized steel as the replacement pipe, and in that case the Cherry Bomb piece would be better than the Mangaflow/Summit SS x-pipes since it will match the replacement pipe material. I do not know enough about welding to comment the integrity of welding aluminized pipe to the OEM SS pipes but it looks like shops are doing it.

As for your Supersprint x-pipe question, no, these $100 x-pipes do not include those long pipes that come with the SuperSprint system. The exhaust shop will add generic pipes to the x-pipe to make it fit into the area where the resonators were. In this case the shop can install x-pipe anywhere they want - up by the engine or more to the rear of the car.

The only place to put your x-pipe in is somwhere along the route where the two pipes are parallel to each other, I pulled some pictures from another thread showing the stock exhaust and then an x-pipe. After the parallel section they bend off to the left/right mufflers. Like Yorgi said, you could put it further back from the front of the car, more towards the back before they veer off. No matter what they need to weld around the entire circumference of the pipe, so they will have to lower (or partially lower) the exhaust. Even if they remove it completely it isn't that much more work, it disconnects from the exhaust manifold just in front of the resonators, maybe 4 bolts? Of course the bolts may be seized so that could make it a bear, but they don't have to remove the exhaust all the up to the engine.

How long are you going to keep the car? From a performance standpiont I am not sure the metal type will make any difference, from a longevity view if you are keeping the car for 2 or 3 years who cares. You live in L.A., there are no salted roads and not a lot of moisture. I am not saying get the cheapest, but don't waste your money getting the ultimate either!

What kind of steel is used for OEM 650 exhausts?

Originally Posted by shtaka

What kind of steel is used for OEM 650 exhausts?

See Yorgi's quality post above - stainless steel.

Right! I misread it and thought it refered to M6's

Thanks for all the advise, the muffler shop in walking distance to my place happens to have a Magnaflow X-pipe so I did the whole installation with them. They charge me $280 out the door for everything. Magnaflow X-pipe, and labor for the piping, they explain because they couldn't weld without taking the whole cat down. Anyway, it's done, the cold start sound is a bit strange to me. But I like how it sounds now.

Thank you all for very detail and passion advise.