RL cat back exhaust....what do you have?

[boisesky]

Ok so I have got some good info on intakes for the RL and have picked out which one I am going with but now I am curious what is available for a cat-back bolt on exhaust. I can't see spending $900+ when I could have a custom built one for less but I have seen some for around $500 or so.

So what are you guys running and what size. I am guessing 3" is the way to go. I just want to make sure I have looked at all options before I go and have my exhaust guy build something. Also it sounds like there is a proper way to lift these rides.....any links to the proper way so if I do go to my exhaust guy he does it right. Thanks for the info!!!!

[JohnD]

Originally Posted by boisesky

Ok so I have got some good info on intakes for the RL and have picked out which one I am going with but now I am curious what is available for a cat-back bolt on exhaust. I can't see spending $900+ when I could have a custom built one for less but I have seen some for around $500 or so.

So what are you guys running and what size. I am guessing 3" is the way to go. I just want to make sure I have looked at all options before I go and have my exhaust guy build something. Also it sounds like there is a proper way to lift these rides.....any links to the proper way so if I do go to my exhaust guy he does it right. Thanks for the info!!!!

There is a lot more to an exhaust system than just sticking on a big ol' pipe, a minimal muffler, and some cool tips. The system should be built, tested, tweaked, refined, retested, retweaked, etc. I've seen these systems being built by Borla for my 2.4L SKY and by Magnaflow for my Red Line. Manufacturers take a lot of time to make sure that they get the diameter, bends and muffler right in combination to present the optimal performance out of the engine. Too much pressure and too little pressure are both bad. There is a sweet spot that a custom-built one-off is not going to be guaranteed to hit on the first pass.

That being said, the two options for the Red Line that I KNOW have gone through a lot of testing are the Magnaflow 3.0 inch and the offering from RPI. Two different approaches. The Magnaflow uses the transverse muffler like stock, and the RPI uses a split and straight pipes out the back. Both will give you improved performance, with more gains coming from the RPI but at the cost of a louder system and more expense.

Manufacturers can afford to spend a lot of time getting their systems just right because they can spread the research cost over many units sold. The local guy can't really do that.

That's my advice, anyway...

[JohnD]

Oh, in case I wasn't clear... I have the Magnaflow on SPIRIT, which was the prototype car used to develop and test that offering. I saw the whole process as it was being done at the Magnaflow research lab just down the street from my house. You can read all about that process here:

Magnaflow Monster - 3.0 Cat Back for Red Lines, Close-up Photos

I could not be happier with the finished result.

[Heat Mizer]

John D,

Since you were involved from the start in regards to the Magnaflow exhaust and you tell us why they chose to use round tips. Evertything about the Sky is squared off or has sharp edges. Why did they choose to use rounded tips especially since the factory one looks so good. Thanks

[boisesky]

Originally Posted by JohnD

There is a lot more to an exhaust system than just sticking on a big ol' pipe, a minimal muffler, and some cool tips.

Manufacturers can afford to spend a lot of time getting their systems just right because they can spread the research cost over many units sold. The local guy can't really do that.

Sorry if I came off like I knew nothing about exhaust or modding rides. The Sky is new to me thats all. I have installed N20, swapped my own heads and cam, headers, ect, ect. My exhaust guy here in Boise built my turbo back exhaust for the WRX we just got rid off and it put down better numbers than a "bolt on system" for much less. Those numbers were proved on a dyno at the best tuning shop in the nation for Subaru, COBB tuning in SLC. He also built my system for my 05 Magnum that also put down better numbers than a bolt on and again that was proved on a dyno here in Boise. Manufacturers do spend a lot of time on exhaust but then rape you on the price.

Like I said I am new to this forum but not new to modding so for now I will just take your advice in that the Magnaflow is a good system....hell that was the muffler on the WRX so I can vouch for that. If had had a big manufacturer down the street from me I would probably have it on my ride and plug them every step of the way too. What ever I do I will post dyno results and if it is done by my exhaust guy I will let him know that he has a little challenge on his hands

Hey Heat Mizer, that is a good point why go with the rounded? My guess is that is was not made specifically for the Sky just make for the 2.0 that is it tied to but that is just my opinion. This car has some of the sweetest lines and the exhaust tips IMO are kickas#!

Thanks for the advice guys!

[JohnD]

Originally Posted by Heat Mizer

John D,

Since you were involved from the start in regards to the Magnaflow exhaust and you tell us why they chose to use round tips. Evertything about the Sky is squared off or has sharp edges. Why did they choose to use rounded tips especially since the factory one looks so good. Thanks

Yeah, I can talk to that a little bit. The factory tips are custom cut just for the SKY - and welded on. They didn't want to have to deal with cutting them off and getting them to fit properly, I'm sure (though you could probably do that yourself if you wanted to.) So they found a multi-purpose tip out of their stock.

They had lots to choose from... The dual on each side that they chose fills up the hole pretty nicely, and the beveled/angle cut does have some sharp creases to it that do compliment the SKY's lines pretty well for a round tip.

Personally I prefer the Borla flat oval like I had on BABY, but Magnaflow doesn't offer anything like that.

You might want to check out my Exhaust Tip Sampler thread to see some different looks...

Exhaust Tip Sampler

[redhotchillipepper]

My wife and I love the stock "square" exaust tips. We are installing the "GM Performance Parts" cat back exaust (like what is on the Redline), a Hahn high flow cat, and the DDM works stage 1 supercharger because we have an automatic and Dave at DDM Works assures me that it will work with an automatic. I will post the dyno results as soon as we get it all together and get it dyno'ed.

[BigSkyCountry]

3" MagnaFlow cat-back here with the quad round tips. Personally, I didn't like the look of the stock square duals. Ray

[xmicro_Redline]

Magnaflow for me also, and trust me, they look way more high end than square tips! I too thought I liked the square when I first got the car, but it got old quick as soon as I realized that you CANNOT clean the damn carbon out fast enough and on the REDLINES, THEY ALWAYS look dirty! Here are some pics of mine!

[boisesky]

Ok so with the 3" that you all are sporting what kind of gains did you get? I have heard upwards of 30+HP.....combined with a CAI I am sure that is pretty realistic. Thanks again!

[xmicro_Redline]

Originally Posted by boisesky

Ok so with the 3" that you all are sporting what kind of gains did you get? I have heard upwards of 30+HP.....combined with a CAI I am sure that is pretty realistic. Thanks again!

On the exhaust side, the Magnaflow has been dyno'd by members at 6-8 HP Gains on it's own, see these threads:

Pontiac Solstice Forum - View Single Post - False dyno reports from magnaflow

This was a heated argument a year or so ago:

Dyno for RL with Magnaflow 3" & CAI

I can tell you when I drove it hard after I got it put on, there is a NOTICEABLE difference. The factory system felt restricted and the Magnaflow felt OPEN!

As far as the CAI, some have proven that they have LOST HP in the heat especially and have removed them. This is due to the closed enviroment of the SKY RL engine compartment and the heat from the turbo. It has been called a Hot Air Intake by some. Read the end of the thread above to see dyno numbers!

[boisesky]

Originally Posted by xmicro_Redline

On the exhaust side, the Magnaflow has been dyno'd by members at 6-8 HP Gains on it's own, see these threads:

Pontiac Solstice Forum - View Single Post - False dyno reports from magnaflow

This was a heated argument a year or so ago:

Dyno for RL with Magnaflow 3" & CAI

I can tell you when I drove it hard after I got it put on, there is a NOTICEABLE difference. The factory system felt restricted and the Magnaflow felt OPEN!

As far as the CAI, some have proven that they have LOST HP in the heat especially and have removed them. This is due to the closed enviroment of the SKY RL engine compartment and the heat from the turbo. It has been called a Hot Air Intake by some. Read the end of the thread above to see dyno numbers!

Wow so it is not as much as stated....interesting. Usually when you open up a turbo charged ride you get more than that. That seems a little low to me but hey if you feel it in the butt dyno then it is worth it. Thanks for the input.

[Bogie]

Originally Posted by redhotchillipepper

I will post the dyno results as soon as we get it all together and get it dyno'ed.

Please dyno stock first!

[boisesky]

Originally Posted by Bogie

Please dyno stock first!

X's 2....gotta do it.

[JohnD]

These are the dyno runs for SPIRIT. First is testing with the 2.5 inch exhaust, then the figures for the 3.0 inch.

I dunno... I've seen the dyno, and know the guys that did the test are on the up-and-up. I also know that they got these numbers from putting the 3.0 on a pre-production test car, and wanted to confirm that they would get the same numbers on an actual production car. We had this conversation before they tested SPIRIT with the 3.0! So to me the numbers are very "real."

I've also included three snaps that I took of the Magnaflow muffler and tips next to the stock on the floor of the Magnaflow shop...

[JohnD]

One other comment... Those dynos were done with the car was just a few weeks old before I had done any other mods, so that is with the stock airbox.

[cerberus]

More independent dyno runs would be nice. With RPi centrally located, I'm sure Eloy would oblige us if we wanted get some folks together for an independently witnessed testing session. My take on the exhuast choices is to go for the look and sound you really like. The differences in claims and numbers are interesting, but I just don't see them trumping personal preference. Once you've picked one and like it, it is what it is. <shrug>

[JohnD]

Originally Posted by cerberus

More independent dyno runs would be nice. With RPi centrally located, I'm sure Eloy would oblige us if we wanted get some folks together for an independently witnessed testing session.

Actually, I think that day is coming. Once I wrap up with my trains for this season (in the next few weeks) then I think I will plan a drop-in on RPI over the summer to see if I can get a dyno reading on where I am at now.

Of course at this point it will be a different dyno, a differnt motor, and all a completely different intake system. I don't plan on going back to stock on this motor any time soon.

But maybe he could oblige me and do a hood closed versus hood open versus mega-fan blowing test to see what difference those actually make. THAT might be interesting!

[cerberus]

Yeah, you're not stock, but it's all interesting. Hey, that's halfway to O/C! I can make that in an hour and a half provided there's not much traffic, lol. Would be cool to catch up and B/S. I don't recall if it was Eloy or C/A who had the DB meter at the last dyno day, but that gets intersting too.