Liquid Anarchy

iTrader: (2)

Simple enough; for performance which side is better? Which side has fewer bends? Shorter Pipe? Etc.

I'm getting a 2½ single made tomorrow afternoon, and I'm wondering wether to make it Passenger Exit, or Driver Exit. So far, I'm siding with Passenger; due to weight. I figure that will help off-set the weight of the driver. Any reccomendations?

bcty

right

Icemark

This idea of weight offset keeps coming up and I must say WTF???

As most of us know, on the FC the factory ran out the driver’s side as well as the passenger’s side for the exhaust and mufflers. What makes anyone think the least bit that removing one side will "offset" any weight? How can you offset any weight by replacing something that was already there???

If anything people should be concerned that the car won't be as balanced as it was from the factory with a single exhaust, by removing half the weight distribution.

So if you are set on a single, ask:
Do I have passengers that will be offended by a louder exhaust?
Will I be offended driving with a louder exhaust?

If you answer yes to either question, route the exhaust output farthest from that person that will be offended while driving. For example you don't want to hear it as much run it out the passenger’s side. Or if your passenger doesn’t want to hear it; route out the driver’s side

banzaitoyota

It has to do primarily with balancing the car for optimal handling. With the stock duals, ASSUME each muffler weighs 30lbs(I am not sure of the exact weight, I will check tonight). If you remove these you lost 30 lbs in each corner of the car. You have a net loss of 0 for each rear corner of the vehicle. Now you add 20 lbs for the new lighter exhaust., Where would you chose to put it? on the drivers side or passenger side. To me, and a lot of folks who autocross: It makes more sense to offset the drivers weight as much as possible. Why do amatuer drag racers move the battery from the front of the car to the passenger side rear? WEIGHT DISTRIBUTION! Yes it can be construed as ****-retentive by the uninformed, but when you are trying to save 1/10th or 1/100th of a second every little bit helps.

jimmyv13

OK, the weight distribution thing is important............ to RACE CARS!!!!!!!

Most of the guys on the foum have street cars, so weight distribution is not that important. I have been under my car many times trying to see which side is optimal for less bends in the pipe for a single exhaust. I have decided that the drivers side exit will have less bends with a custom installation, and like Icemark said the drivers side exhaust will be heard more by the driver, which I want.

Icemark

I guess I am not making my point clear. Using your above formula (as I am not inclined to actually look up the actual numbers this minute).

So you have a car that was designed for a 100lb-200lb person in the drivers seat and the equivelent passengers weight 30% of the time. You remove 60 lbs (30 each side), but the weight removed is aft of the rear axle line.

Then you bolt on your 20lb single exhaust, to the driver side... with that you are 10lbs light on the drivers rear, and 30lbs light on the passengers side all aft of the rear axle line. Now you could move the battery to the passengers rear corner to help re-balance the car, but...

Or you bolt your 20lb single to the passengers side. Now the passengers side is 10 lbs light and the driver side is 30lbs light. How is that balanced???

Oh wait... maybe the driver is 30lb over weight... and weighs 230lbs... now it would balance equal to the factory weight, but wait... your passengers side is still 10lbs light and you have shifted 30lbs to the middle of the car that was at a corner.

so see this idea of balancing the car is lame, and actually doesn't work the minute you replace the exhaust with a single. You actually un-balance from the factory balance/setup no matter what you do.

So I stick with my WTF are you thinking when you say balance the car with a passengers side exhaust.

So get what will sound the best for you, and don't worry about this so called balancing act that people are trying to get you to subscribe too.

jimmyv13

yeah, what he said.

Liquid Anarchy

iTrader: (2)

I'll stick with what I was doing. Exhaust is going passenger exit. Unfortunatly, due to funds ( Mandrel is EXPENSIVE here ) I'm getting a notch-bent, Ionized Steel exhaust made temporarily.

FYI: My car IS a daily driver.... but after it's up, and well it's going auto-x'ing.

TeamWireRacing

You guys are assuming that a car is perfectly balanced right from the factory, so why mess with it?

The reality is that Mazda was probably concerned more with costs and packaging than it was with balance when the car was built. Therefore, any time you have a chance to remove some weight and relocate other weight, you want to do it in the most advantageous manner possible, from a performance standpoint.

Ice, you can probably see the point better if you take the car from its starting point, as in w/o driver and w/o rear exhaust. If you add the exhaust only to the passenger side (call it 20 lbs.), the rear weight will go up, the RH weight will increase, as well as the LF/RR diagonal weight. Very little weight increase will show up in the front, and a marginal gain might be seen in the RF/LR diagonal number. Now add a 200 lb. driver, and see what happens to the numbers. The LH weight will increase dramatically, and the diagonals will split the weight increase between them, although probably not 50/50. If the exhaust were to exit to the driver's side, the LH weight would rise even further, without much change in the diagonals. Since the diagonal, or cross weights, are the most important numbers, you want to pay the most attention to them. And make improvements to the overall balance whenever you can.

If you have to replace something, why not make it better?

NZConvertible

This really is a pointless argument. The rear section of the exhaust weighs so little compared to the weight of the car, the actual measured difference in weight distribution is going to be minute. The difference in noise is going to be zero. Flow is a non-issue because the exhaust has to run down the centre of the car anyway, and then turn towards whichever side. Last time I checked, left hand bends flowed just the same as right hand bends. It all comes down to this. What side do you think looks best.

Pinfield357

i think duel looks the best hehehe

Evil Aviator

The weight distribution depends on what you have done to your car - roll cage, fuel cell, battery size/relocation, etc. To be accurate, you need a set of scales http://www.pitstopusa.com/LONGACRESCALES.asp to get the weight at all 4 tires with no exhaust installed, you in the driver's seat with your racing gear on, and the amount of fuel that you normally race with. Then you can calculate the needed weight by using the formula of Weight * Arm = Moment. Once the exhaust is installed, then you can rearrange things (battery, fuel pump, jack, etc.) as needed to fine tune the weight distribution.

I know that you don't have the cash to do this, nor the driving experience to tell the difference, but it's something to think about for the future.