New Custom Atom Exhaust System

[Kim]

The stock Atom exhaust system is known to be fairly restrictive and quiet, having been designed to satisfy a host of noise ordinances, especially in the UK. Owners have also found that the stock internals have tended to deteriorate quickly.

Wanting something that provided more flow, created cheap additional power, weighed less, would last longer, looked better, and sounded more robust, I asked my brother Alan (who builds and sells racecars) to take a whack at the Atom. Here's what he came up with:







The system is all stainless steel using dual 2" pipes doubling the exhaust flow of the original from 2" to 4". (Interestingly, Mark Swain with TMI explained to me that the Honda K20R engine has been tuned by Ariel such that it needs virtually no back pressure from the exhaust system to run perfectly - so there are only benefits to enhancing the exhaust flow.)

Have you noticed how several of the TransAm and NASCAR race cars are sounding more like IndyCars these days? That’s because they are using a synchronizing crossover exhaust system. Alan also incorporated a really neat synchronizing crossover pipe (aka an X pipe) like that found in Indy cars. These systems provide a 1% to 5% gain in both torque and horsepower at all engine speeds over standard systems, and they make four-cylinder engines sound like they have six or eight cylinders.

In addition to increased power - whatever that might be - the new exhaust sounds great and looks fantastic IMO. Take a look and let me know what you think.

[Norm]

Now if it came in an Eco version ...

Looks good Kim!

[silver]

Now if it came in an Eco version ...

Looks good Kim!

Yeah I really want an exhaust that goes inside the frame.

good news is that my tuner guy just opened his shop and moved so he's now 10 minutes away instead of an hour. AND he's getting a Mandrel Bender, we could at least remake the mid pipe so that it goes inside, and replace that 2 ton muffler with something lighter and better looking.

Norm, you can fix the header since you need it to be better than what it is.

[Kim]

You're right, Silver. The original weighs a lot! I forgot to mention the considerable weight savings achieved by going to a custom exhaust.

[silver]

Norm and I.actually have a custom exhaust already, it just isnt what we really wanted, our mufflers are at least 20lbs heavier than stock!!!

[Gage]

I like it Kim! It would be great to hear a sound clip of the car at idle and racing.

[Payne]

Kim-

So he is using the standard header, then instead of the 2 into 1 exhaust he is running 2 pipes all the way through the muffler?

Please post sound clips, I might be interested in the setup.

Thanks,
Jason

[silver]

one thing he mentioned is that there's an X pipe, it's hard to see but I believe there's a glimpse of it at the very bottom of the exhaust.

[Kim]

Kim-

So he is using the standard header, then instead of the 2 into 1 exhaust he is running 2 pipes all the way through the muffler?

That's right. Instead of two 2" exhaust pipes leading into one 2" pipe, Alan has used two 2" pipes running all the way to the exhaust tips - or tip. You can either have two 2" exhaust tips, or one large 4" or 5" exhaust tip. I'm changing to the latter next week; it should change the exhaust note and look great!

one thing he mentioned is that there's an X pipe, it's hard to see but I believe there's a glimpse of it at the very bottom of the exhaust.

Here's a better photo of the X-pipe:





And here are some speed tests showing the performance differences between an H-pipe and an X-pipe:







NOTE: Performance figures are not from an Ariel Atom.

[silver]

hopefully those aren't your times................otherwise I'd have to make fun of your slow time