Had Roe Hi-flow cats installed today!!

[ElDiablo Viper]

How long did it take you do install it? Also how much RWHP you think it is worth. I have K&N and Corsa 3''.

 

[treynor]

Previous experience shows stock cats --> high-flow cats nets ~7 RWHP & ~10 RWTQ on a car with headers & exhaust.

 

[ElDiablo Viper]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by treynor:
Previous experience shows stock cats --&gt; high-flow cats nets ~7 RWHP & ~10 RWTQ on a car with headers & exhaust.

<HR></BLOCKQUOTE>

Is it worth doing without headers?

 

[RECOIL]

Keeps your side sills cooler which can prevent discoloration.

It's worth doing.

Steve

 

[Motor City Mad Man]

I had some Roe hi-flow oval 3" cats installed today. My exhaust was already fairly loud due to my headers, Borla exhaust and no mufflers. After the hi-flow cats were installed, the loudness at idle does not seem that much more than it was before, which is good as far as I'm concerned. The sound at full throttle is awesome. A bit louder than my old setup. I am going to hook up a Roe VEC-1 later this week and will dyno the car at the end of this month to see how much HP I picked up in total. It does see more responsive now.

 

[meggleto]

&gt;&gt;&gt;&gt;&gt;Previous experience shows stock cats --&gt; high-flow cats &gt;&gt;&gt;&gt;&gt;nets ~7 RWHP & ~10 RWTQ on a car with headers & exhaust.

Ben,
I was hoping it would be like 15rwhp at the hp peak and maybe even more at other RPMS.

Do you think you may have gotten less of a gain since you installed the Mopar ECU at the same time?

Also did you see more than a 7rwhp gain at rpms other than peak?

 

[treynor]

This graph shows four curves for my '01 RT: (1) stock, (2) tubes & filters, (3) above plus belanger headers + exhaust; (4) above plus 3" high-flow cats. As you can see, the high-flows picked up substantial power across the powerband, including gains larger than the peak changes.

You must be registered for see images

 

[Motor City Mad Man]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by ElDiablo Viper:
How long did it take you do install it? Also how much RWHP you think it is worth. I have K&N and Corsa 3''.

<HR></BLOCKQUOTE>

It took about 2 hours to install the 2. It claims to get as much as 14-17 HP I think. I guess I'll see what my dyno run does. Treynor, I sure hope I don't only get 7 HP out of this. Do you have the Mopar performance ECU? I remember hearing some people losing HP with that. Anyways, the side sills are much, much cooler and the sound at full throttle is incredible. I don't regret getting this mod.

 

[treynor]

I tried dynoing with both the stock and MOPAR ECU, and found no significant power difference between the two.

 

[meggleto]

Ben,

Thanks for the graph! Wow, it looks like you gained almost 25ftlb in some areas. It definitely looks like a good mod!

MotorCity Madman, If you get the 15rwhp at the hp peak and get the gains he got everywhere else there's no way you should be disappointed. The area under the curve is much larger! The rwhp change only counts for dyno bragging rights. The rest of the curve shows up at the track.

 

[ElDiablo Viper]

Thanks for posting the numbers. I'm wondering if it would be better to take the cats completly. I don't care about the inspection. Also do you get any computer problems with hi flow or no cars. Thanks.

 

[Motor City Mad Man]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by ElDiablo Viper:
Thanks for posting the numbers. I'm wondering if it would be better to take the cats completly. I don't care about the inspection. Also do you get any computer problems with hi flow or no cars. Thanks.<HR></BLOCKQUOTE>

From what I hear, I think some of the newer Vipers are setting trouble codes on the computer when using no cats. I guess it depends on the year. Also, from what I have read on this forum, some people that switch to no cats regret it because of the exhaust fumes. There also seems to be not much more of a HP gain from going from h-flow cats to no cats.

 

[Motor City Mad Man]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by meggleto:
Ben,

Thanks for the graph! Wow, it looks like you gained almost 25ftlb in some areas. It definitely looks like a good mod!

MotorCity Madman, If you get the 15rwhp at the hp peak and get the gains he got everywhere else there's no way you should be disappointed. The area under the curve is much larger! The rwhp change only counts for dyno bragging rights. The rest of the curve shows up at the track.

<HR></BLOCKQUOTE>

Meggleto, the drive home from getting the hi-flow cats on was wonderful. Either I just feel like it has more power or the increased sound of the exhaust made me think it does. The exhaust at WOT is like music to my ears. I don't think I need to upgrade my stereo now because I would rather just listen to the engine.

Also, to anyone out there, after looking at my stock cats I can't believe exhaust can even get through that mess. On one cat I could not see any light at all out the other end and on the other I could barely see any. Seems to be a very restrictive setup or else my stock cats were just shot. Whatever the case may be, these hi-flow cats really opened things up.

 

[JonB]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Motor City Mad Man:
....Also, to anyone out there, after looking at my stock cats I can't believe exhaust can even get through that mess. On one cat I could not see any light at all out the other end and on the other I could barely see any. Seems to be a very restrictive setup or else my stock cats were just shot.
<HR></BLOCKQUOTE>

We have seen cats deliver ~6 hp and up to 25! The Year Matters, but as MAD MAN found out: SO DOES THE CONDITION OF THE OE CATS !

Not All cats are created equal. Most are just 'universals' that have tips welded on. Maybe even no tips! At the other end of the scale are 500+ CFM metallics like Ben/Doug Levin is using on the S/C-2 cars. No ceramic substrate! See daylight thru em easily. As seen on Euro V-10 / V-12 supercars.

But they run cooler, and "tune" the exhaust note deeper and louder.. HP is just a bonus.......