Anyone running GMG WC Sport Header?
11-30-2011, 11:12 PM
#16
Rennlist Member
I didn't say 1 DE, I said 1 DE 'season' - and in a car that sees 8500rpms.
If you really search and ask around - the shops will confirm this - this is not new news.
Porsche going to 300 cell cats in the 4.0 pretty much confirms at the very high rpms - it is the cats and unrestricting them is where some free HP can be found.
I have a lot of dyno experience with lots and lots of setups in the turbo world and can tell you that very high flow cats do make a real difference
If you really search and ask around - the shops will confirm this - this is not new news.
Porsche going to 300 cell cats in the 4.0 pretty much confirms at the very high rpms - it is the cats and unrestricting them is where some free HP can be found.
I have a lot of dyno experience with lots and lots of setups in the turbo world and can tell you that very high flow cats do make a real difference
12-01-2011, 12:13 AM
#17
Three Wheelin'
Somebody please enlighten me on cats because it's always been a bit of grey area.
What's the difference between 100 cell vs 200 vs 400?
I assume not all cats of same cell count are created equal. True?
I've heard other board sponsors/members make reference to stock cats not lasting long. How much truth is there to this?
What's the difference between the stock cats on 3.8 vs 4.0 RS?
What's the difference between 100 cell vs 200 vs 400?
I assume not all cats of same cell count are created equal. True?
I've heard other board sponsors/members make reference to stock cats not lasting long. How much truth is there to this?
What's the difference between the stock cats on 3.8 vs 4.0 RS?
12-01-2011, 02:07 AM
#18
HJS are the only cats I would put on my car whether its the RS or Golf.
The higher the number.. the more CELLS the cats have and it has more surface area for the exhaust gases to have to push through...so 400 cell cats will have 2 times the surface area.
200 cel cats on the left.....400 cell on the right
Less area is better for flow and more efficient, hence less power is lost.
Straight pipes would be ZERO cell.
The higher the number.. the more CELLS the cats have and it has more surface area for the exhaust gases to have to push through...so 400 cell cats will have 2 times the surface area.
200 cel cats on the left.....400 cell on the right
Less area is better for flow and more efficient, hence less power is lost.
Straight pipes would be ZERO cell.
12-01-2011, 08:09 AM
#20
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nizer, 100/200/400 etc refers to the number of holes in the cat; more holes more restriction.
less holes, more flow, but also creates more pollution and can cause cel on oem tune
not all cats are created equal. basically, the lower cell count flows (breathes) much better at high rpms, but can be a dog in the lows, so depends on the type of car and it's application.
that is why 200 or 300 are a good all-round application.
less holes, more flow, but also creates more pollution and can cause cel on oem tune
not all cats are created equal. basically, the lower cell count flows (breathes) much better at high rpms, but can be a dog in the lows, so depends on the type of car and it's application.
that is why 200 or 300 are a good all-round application.
12-01-2011, 08:24 AM
#21
I am running the GMG headers, sport cats and center section on my 2010 GT3. Based on my PerformanceBox based power calculations (before and after), the setup added +20 hp at the wheels. High quality machining and welds. The setup is loud, especially above 4k rpms under full load. Sounds great at the track. Approx 5% gain in hp is certainly not dramatic, but probably worth a few tenths in lap time.
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2010 Black GT3
2008 Silverstone M5
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2010 Black GT3
2008 Silverstone M5
12-01-2011, 09:25 AM
#23
Somehow it always amazes me when this subject comes to discussion NOBODY ever gives even the slightest thought/consideration to products produced by M&M from Germany. Distributed by FVD in the USA.
All the other darling names ( which are good ) are mentioned but never M&M?
Oh well
Ranger (Sua Sponte)
All the other darling names ( which are good ) are mentioned but never M&M?
Oh well
Ranger (Sua Sponte)
12-01-2011, 09:49 AM
#24
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I am running the GMG headers, sport cats and center section on my 2010 GT3. Based on my PerformanceBox based power calculations (before and after), the setup added +20 hp at the wheels. High quality machining and welds. The setup is loud, especially above 4k rpms under full load. Sounds great at the track.
12-01-2011, 05:26 PM
#25
I am still running the side mufflers. With the sport button OFF, the sound level is still loud but reasonable, especially at low rpms. With the sport button ON, you can set off car alarms in the garage.
________________
2010 Black GT3
2008 Silverstone M5
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2010 Black GT3
2008 Silverstone M5
Last edited by jbxea1; 12-01-2011 at 07:30 PM.
12-01-2011, 05:44 PM
#26
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I am running the GMG headers, sport cats and center section on my 2010 GT3. Based on my PerformanceBox based power calculations (before and after), the setup added +20 hp at the wheels. High quality machining and welds. The setup is loud, especially above 4k rpms under full load. Sounds great at the track. Approx 5% gain in hp is certainly not dramatic, but probably worth a few tenths in lap time.
they sure look quality and gmg really has a great rep, But 20hp?
damn I really need to get my exhaust system sorted out soon
buying from FVD could be pricy being sent from over seas I imagine gmg being bit better being in Santa ana, CA
I know they are on members on here somewhere, maybe they can let you(us) know about the power gains from the different cel cats they sell
12-01-2011, 07:27 PM
#27
My dealer did the install. Cost for the headers is listed on the GMG website (there is a discount if you buy the center section also). They came with 200 cell sport cats and I am not sure if they offer any other cats with the setup.
_________________
2010 Black GT3
2008 Silverstone M5
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2010 Black GT3
2008 Silverstone M5
12-01-2011, 08:25 PM
#28
Rennlist Member
Does the header install require a re-map of the engine management software to optimize performance?
12-01-2011, 09:31 PM
#29
Race Director
Somehow it always amazes me when this subject comes to discussion NOBODY ever gives even the slightest thought/consideration to products produced by M&M from Germany. Distributed by FVD in the USA.
All the other darling names ( which are good ) are mentioned but never M&M?
Oh well
Ranger (Sua Sponte)
All the other darling names ( which are good ) are mentioned but never M&M?
Oh well
Ranger (Sua Sponte)
12-01-2011, 09:51 PM
#30
http://www.excellence-mag.com/issues...s-group-gt3-rs
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2010 Black GT3
2008 Silverstone M5