PDA

View Full Version : Power gain from 3" catback exhaust



Ijustgotone
25-01-2012, 11:02 PM
Hi all,

This is my first post as a member! I have just brought my first hsv (e3 clubsport r8, MY12, perfect blue) and am looking at a walkinshaw 3" catback exhaust and am hearing varying reports on what the power increase would be. Some say 10% others say you won't get 10% without a cold air intake etc.

Hoping someone will be able to help clarify what the % would be.

Btw - my car is a demo and I still have to wait until March to get it......counting down the days!

HSV085
25-01-2012, 11:08 PM
APS did a before & after power run when mine went in for a hm 3inch catback which did not gain any additional hp, we fitted one of their cai units which saw an instant jump in power(gain of 22rwkw).

Sniper
25-01-2012, 11:42 PM
APS did a before & after power run when mine went in for a hm 3inch catback which did not gain any additional hp, we fitted one of their cai units which saw an instant jump in power(gain of 22rwkw).

Correct . . power gain will be virtually ZERO . . . and you will have a loss of torque . . . tune with OTR will sort it . . . please understand that if you leave your stock HSV LS3 Headers on the car . . the outlet is about 2 1/4 " . . . so flow is a bit messy!!! . . . if you carefully make your choices in Headers, OTR and Tuner . . . your power gain will be about 20 - 30kw . . . but your torque gain if your combo is correct will be huge . . . and your Clubby will feel expedentially more powerful as a result!!!

adr8
25-01-2012, 11:47 PM
As above you would be lucky to see an increase of 5rwkw with just a catback exhaust. Check out the KPM Motorsport website they give you a before and after dyno graph(no tune) to show increase in performance even if just getting a catback exhaust.

I copied this from their website

"All KPM Holden Performance exhausts are made with only the highest quality materials, Australian sourced and developed products, which we guarantee not to drone*. We are also able to provide a conditional Guarantee on our Full 304 Stainless Steel Systems.

Our Holden Performance exhaust systems are accurately checked on our dyno and specification sheets are provided with before and after readings."

**Dyno testing refers to a before and after exhaust fitmant power check on the dyno. It does not refer to Dyno Tuning in any way.
It is carried out to supply the customer with a dyno power graph increase from the exhaust upgrade.

You might want to also look at Oz Garage S2 Episode 9 exhaust comparo they show an increase of 8rwkw with 2.5" catback, then go on to test it with tri y headers, then 1 3/4 headers then 1 7/8 with 3" system.

d488y2
26-01-2012, 07:26 AM
APS did a before & after power run when mine went in for a hm 3inch catback which did not gain any additional hp, we fitted one of their cai units which saw an instant jump in power(gain of 22rwkw).
+1 for APS they did a great job on my car :D

Ijustgotone
26-01-2012, 08:16 AM
Thanks all.

JDHSV
26-01-2012, 10:58 PM
Wish I had of seen the Oz Garage footage a couple of weeks ago.... great information and very informative, kept in simple terms.


As above you would be lucky to see an increase of 5rwkw with just a catback exhaust. Check out the KPM Motorsport website they give you a before and after dyno graph(no tune) to show increase in performance even if just getting a catback exhaust.

I copied this from their website

"All KPM Holden Performance exhausts are made with only the highest quality materials, Australian sourced and developed products, which we guarantee not to drone*. We are also able to provide a conditional Guarantee on our Full 304 Stainless Steel Systems.

Our Holden Performance exhaust systems are accurately checked on our dyno and specification sheets are provided with before and after readings."

**Dyno testing refers to a before and after exhaust fitmant power check on the dyno. It does not refer to Dyno Tuning in any way.
It is carried out to supply the customer with a dyno power graph increase from the exhaust upgrade.

You might want to also look at Oz Garage S2 Episode 9 exhaust comparo they show an increase of 8rwkw with 2.5" catback, then go on to test it with tri y headers, then 1 3/4 headers then 1 7/8 with 3" system.

d488y2
27-01-2012, 06:40 AM
Wish I had of seen the Oz Garage footage a couple of weeks ago.... great information and very informative, kept in simple terms.

Here's the link
http://www.hp-f.com.au/media/hpf-tube/oz-garage-season-2-eps/oz-garage-s2-ep9-online-ve-exhaust-comparo/

adr8
27-01-2012, 01:37 PM
Our Holden Performance exhaust systems are accurately checked on our dyno and specification sheets are provided with before and after readings."

**Dyno testing refers to a before and after exhaust fitmant power check on the dyno. It does not refer to Dyno Tuning in any way.
It is carried out to supply the customer with a dyno power graph increase from the exhaust upgrade.


Well I just got an email from KPM Motorsport after I inquired if there was any loss of torque when fitting a 3inch catbact exhaust on to the LS3 headers without getting it tuned and their reply was there would be no loss of torque.

rodders188
01-02-2012, 12:21 PM
On a stock LS3 a twin 2.5'' catback is suffice, i would'nt get caught up in big diametre catback is better, Why not just look at a pacemaker mid section and retain the rear mufflers. Sniper on here, has that. There are other options than KPM systems.
Hi Tech Mufflers do a catback for your car as do Xforce.