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edo · Dec 3rd, 2002, 03:18 AM

Quote:

Genraly so called aftermarket high flow cats don't flow better than stock but I personaly think the Magnaflow ones are better, their shell is actualy designed on a flow bench.

Mike

Borrowed from a post by a Magnaflow rep:

Quote:

Random technology vs Car Sound High Flow Converters- why Car Sound Flows better

First of all the facts-

Every converter has to use a brick that has at least 400 cells per square inch.

Any less and the converter will not get EPA approval, both Car Sound and Random Technology are using the same 400 cells per square inch, so one brick can not outflow the other...

The difference must then be in the casing-

1. Have you got the groove???

The brick is a brittle piece, so it has a rubber- like cushioning mat that cushions the monolithic catalyst. (the brick)

This rubber- like mat is about 1/8th of an inch thick.....

If you look at a Random converter, it has a smooth body so that mat sits out in the open...with the exhaust gas hitting it causing the air to not flow smoothly.....

The Car Sound converter has grooves built into the casing, which lets the matting sit recessed into the casing. This means the exhaust is not hitting that 1/8" piece causing turbulences.

Not only does this allow the air to flow smoother, but it helps to protect the matting from the exhaust flow which will eat away at it and it keeps the brick in place when the metal of the converter body expands as it gets hotter.....

2. You have to see it from the right angle-

If you look at the two converters side by side, you will notice that the RT has a lot sharper bend where the casing decreases and increases from the actual exhaust piping.....

If you look at the exit side of the converter- what flows better-

air hitting a 15 degree angle or a 45 degree angle- sharp curves in the case cause less flow......

(not only does the more obtuse angle cause an easier exit for exhaust out of the converter, but upon entering the converter, it gives more room for the air to spread out, reducing emmsions and providing more even wear on the brick)

3. Get connected-

Look at where the inlet and outlet pipes are welded into the converter body......

Instead of using a butt weld, which causes a ridge where the two connect, Car Sound uses a 1/2" overlap, which means that the place where the body connects to the piping is smooth....

the overlap also provides a better surface area to weld on as well making it a stronger weld.

Those are three of the main reasons a Car Sound converter will outflow a Random Technology-

Again, we all must use the same 400 cells per square inch, so the real difference in flow is created with the casing-

cheap prices:

http://exhaustproslinc.com/brcarunconwi.html

Carsound/Magnaflow affiliated companies.

-Ron