Down Pipe Question

[Focal204]

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Will high flow catted downpipes have the same performance as Catless downpipes? I know they will smell different but besides that are there any other differences.

[Svergel91]

Catless have no restriction which =more flow=more hp??

[CaryTheLabelGuy]

Honestly, going with a aftermarket catted downpipe is a waste of money. The stock downpipes are already pretty high-flow and great performers. If you're going to go through the time and money to go with aftermarket downpipes, catless is really the only option.

[mike@x-ph.com]

Originally Posted by Focal204

Will high flow catted downpipes have the same performance as Catless downpipes? I know they will smell different but besides that are there any other differences.

Yes you can run the same maps and will get same performance (stock turbos)

[SeanWRT]

Originally Posted by CaryTheLabelGuy

Honestly, going with a aftermarket catted downpipe is a waste of money. The stock downpipes are already pretty high-flow and great performers. If you're going to go through the time and money to go with aftermarket downpipes, catless is really the only option.

There're better cats in the market than stock, meaning freer flow and greater catalyzing capability with certain cells.

Not everyone chase maximum power. When not setting crazy high boost target, the difference between high flow and catless is negligible.

Many of us value drivability more than others, I for one would rather stay far far away from a smelly car and will not go catless however much power it makes. To each their own though.

[CaryTheLabelGuy]

Originally Posted by SeanWRT

There're better cats in the market than stock, meaning freer flow and greater catalyzing capability with certain cells.

Not everyone chase maximum power. When not setting crazy high boost target, the difference between high flow and catless is negligible.

Many of us value drivability more than others, I for one would rather stay far far away from a smelly car and will not go catless however much power it makes. To each their own though.

Okie dokie.

The difference between stock and aftermarket catless downpipes are somewhat minimal, but you can think what you want if it makes you sleep better. At stock boost levels, you won't gain much power, but you will gain slightly better throttle response. You won't notice the catless downpipes until you start to increase boost pressures over stock and if you're going to go with catted aftermarket downpipes, you're almost back where you started as it's been proven over and over again, the stock downpipes are very well designed.

Go catless or stay stock. You'd get more gains by going with a good midpipe than a catted aftermarket downpipe.

Also, what does drivability have to do with smell?!?

[CPWINCH]

Originally Posted by CaryTheLabelGuy

Honestly, going with a aftermarket catted downpipe is a waste of money. The stock downpipes are already pretty high-flow and great performers. If you're going to go through the time and money to go with aftermarket downpipes, catless is really the only option.

This.

[STR8-6IX]

catless downpipes = more performance then catted.

agreed with what others have said. either you go catless or keep the current one.

[Fabspeed Motorsport]

Catless will definitely yield more power than a catted setup but the smell will be much more noticeable. Also it will be much louder than a high-flow catted option. This also depends on the rest of your exhaust setup.

[mquatro]

Why wouldn't you go catless? No point in getting catted aftermarket DP's imo

[SeanWRT]

Originally Posted by CaryTheLabelGuy

The difference between stock and aftermarket catless downpipes are somewhat minimal, but you can think what you want if it makes you sleep better. At stock boost levels, you won't gain much power, but you will gain slightly better throttle response. You won't notice the catless downpipes until you start to increase boost pressures over stock and if you're going to go with catted aftermarket downpipes, you're almost back where you started as it's been proven over and over again, the stock downpipes are very well designed.

Go catless or stay stock. You'd get more gains by going with a good midpipe than a catted aftermarket downpipe.

Also, what does drivability have to do with smell?!?

Be less full of yourself and try listen.

I take it your point being stock cat is good enough, to the point simply no gain to be seen until catless system is put in place, either boost cranked up or not.

Though that doesn't seem very true in the grand scheme of things, I'll assume it is specifically to S55 application.

Using that assumption, the next question would be: why do cat mod at all? The difference is so little that you have to go full catless to find it and no point of balance somewhere in between is worth looking at in your opinion.

There is a diminishing return for almost every investment or sacrifice, I believe cat mod is no exception. Most of "high flow" cats in the market do basically nothing other than sit in the middle of pipe making back pressures. But there are good cats with its superior material and design that's proven to be effective in freeing flow and reducing smell and that last even longer than stock.

In deciding how free flow is enough free flow, you have to consider diminishing return as well. Put it this way, to reduce back pressure, you'd rather have exhaust pipe diameter match the power engine makes, rather than be as big as underneath fitment allow, because you're only making noise not power going too big. Well can't say the same but similar goes to cats. For the record, S55 could be different though.

There are people valuing power gain much more than anything else and will go as far as possible in pursuing the last bit of it. So there is a market for it no mention it's a lot easier to step into catless business from a manufacturing perspective. Hence full of hypes in it.

Again "return" has different meaning, dependent of whom you speak with.

[mike@x-ph.com]

Originally Posted by mquatro

Why wouldn't you go catless? No point in getting catted aftermarket DP's imo

Some prefer catted because it will give you 75% of the power increase with no gas smell and lower sound

[shahano]

I have catless and have never had any gas smell. Not sure what smell you guys are talking about.

[THX]

Originally Posted by shahano

I have catless and have never had any gas smell. Not sure what smell you guys are talking about.

Have you secondary cats in the midpipe?

[mike@x-ph.com]

Originally Posted by shahano

I have catless and have never had any gas smell. Not sure what smell you guys are talking about.

Some are more sensitive to the smell than others, i dont smell it

[///Pip]

Originally Posted by mike@x-ph.com

Some are more sensitive to the smell than others, i dont smell it

I Don't smell it either !

We still have 2 cats in the mid pipes anyway.

BTW, awesome awesome service Mike ! getting the DP to Singapore haha

Thanks again.

Will write a full review soon

[mike@x-ph.com]

Originally Posted by ///Pip

I Don't smell it either !

We still have 2 cats in the mid pipes anyway.

BTW, awesome awesome service Mike ! getting the DP to Singapore haha

Thanks again.

Will write a full review soon

Thank you

[Jeff@TopGearSolutions]

Originally Posted by shahano

I have catless and have never had any gas smell. Not sure what smell you guys are talking about.

It's not as bad on these newer cars. If you had catless on other cars, like Japanese cars or older vehicles - they were typically a lot more potent when coming up to red lights and such.

Also if the secondary cats are still in place you really don't smell much because of that.