RB mufflers, no cat, true duals.

 

Is is even good to port when you have true duals? or are some ports bad, and some ports good.

EDIT: so that video of your car is stock other than the exhaust?..if it isn't what else you have on it?

 

In general the more port overlap you have, the less reason you have to use a true dual. A large overlap engine such as a bridge or a peripheral port needs to have a collected system to help scavenge the other side. This is very important with these port styles. A true dual does not scavenge. You have to collect to scavenge. A true dual does tune though so don't think it can't work. A large overlap engine is much more sensitive to exhaust backpressure than a stock or streetported engine is. A true dual does have more backpressure than a collected system as it has no scavenging ability which pulls gasses down the opposing pipe. The benefits of the true dual on a less agreesively ported engine outweigh the negatives though. If you use a true dual on a bridge or peripheral ported engine, it will fall flat on it's face on the top end. I have a dyno chart of an unnamed person who has a peripheral port running a true dual system with 2 Walker turbo mufflers. The owner claims the car makes 310 hp apparently by virtue that it is a p-port but the dyno chart suggests otherwise as it falls on it's face at 7500 rpm.

Different lengths in a dual system will tune for a different powerband just as with a collected. A longer system will give you more low end and a shorter one will give you more top end. Don't assume that because a system is long and runs to the back of the car that it will only have low end and no top end. Not true. In fact it is a very nice length as it makes your average powerband real nice. A short true dual may ultimately peak higher but the average will be lower and the peak may be after redline anyways so it would be no good there.

A collected system is also length dependent. There are many things that come into play with a collected system that can help or hurt it. Obviously we have distance from the engine to the collector. This is an important thing when deciding how long to make the primaries. This distance can affect your powerband. So can the diameter of the tubing. The size of the collector can also affect the powerband independent of the primary lengths. As with anything if it gives a gain in one area it will be a loss in another of the powerband. The true duals suffer the same fate. you can't have everything. The key is designing a system that makes the best power where you need it an loses in the leas important areas. For a street car a wider powerband that may lose a couple of peak power is the best setup. If a collected system fell on it's face at one point on a certain engine, it just means that it wasn't the best designed collected system for that application. Changing something about it could remedy the issue so don't think that all collected systems have the same problems in the same spot. They don't. Neither do duals.

There's alot to condiser when it comes to exhaust design. A true dual system removes alot of complexity. If you start to second guess yourself when it comes to the best overall system, you'll end up confusing yourself to death and get nowhere. On a stock or a streetport system, if you can live with the exhaust tone, you'll probably be very happy with a true dual setup.

It's hard to speculate how much power your car will make. You are more limited by ecu than you are by port size. A properly tuned standalone ecu on a stock port will actually get you more power than a streetport on a stock ecu so it's really hard to tell. Just know that your exhaust won't be the issue as long as the stock manifold is gone.

 

The apex is a split exit (as in one muffler on each side of the car).

 

i am looking into getting the Wolf 3D standalone too


so what would an estimation be with a streetport, true duals, intake, and standalone?

 

What kind of streetport?

Some streetports make more then some Bridge ports. Its all about efficiency.

:O!

Also is it just a filter or a true CAI?

 

a mild streetport done by rotary resurection...

its only a filter right now..

but i'm making it a true cai

 

160-185 to the wheels. If its tuned hotly, then maybe more :O!

 

how much power does an s5 have stock?

 

To the wheels? Like 120-135 ish new. Search the dyno section, they got TONS of information about dynos and stuff.

:o

 

160hp and 140ft-lb at the flywheel, or 136hp and 119ft-lb approzimately at the wheels with a 15% drivetrain loss.

 

170-180 WHP maybe? Like any HP figure it's a total shot in the dark, and depends on tuning. Go to the dyno/slips section and look for a similar car.

 

I'm going to say 150 if you are really really lucky.