Exhaust help:Shorties w/HF cats or LT w/HF Cats - Page 2 - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Modernmusclecar · 04-06-2020, 03:56 PM

Shorty headers with the Solo HI flow cats are the only way you will get a power increase. The stock cats are the major restriction point. If your an l99 get the Ls3 Solo hi flows the L99 have a connection to absorb vibration when the dod is active and they leak. The Ls3 is solid stainless body. The Jbas with the Solo hi flows don't need a tune...but on cars newer then 2011 I believe they tripped a cell and then you need extenders.

Yellow 1 · 04-08-2020, 10:34 AM

Probably easier to move state! You guys over there seem to have it worse than over here for modifications. Seriously though; long tubes for the win.

rich2342 · 04-16-2020, 10:03 AM

Quote:

Originally Posted by JRBumfuddle

I have JBA shorties with a CARB sticker. Definitely felt more torque compared to stock manifolds. Then added JBA HF cats, and noticed another bump in torque, and louder exhaust. I had RDP tunes for both stages. Have to smog this summer, so will change cats back to stock, which is easy.

Do you have any sound clips? MA. Is similar to California in that I can't run LT's

VR Baron · 04-16-2020, 11:56 AM

In response to some saying shorties and hiflows make no power or little. As I posted earlier, at least if you get jba shorties and hiflows you get around 20, 11-12 from hiflows and 8-9 with shorties. That’s on a car with just cai and catback. A mild “smog” friendly tune is another 10-12. Three of us, two m6 and one l99, same dyno, modded as I said, all made 30-32 hp with tune. Tunes were 10-12 of that. Peak tq with tune is about 24. Would we prefer LTs here in Kali? Yes of course. A bit more power and they don’t fall off over 5500 rpm.
But again in Kali, not a lot you can do

04-08-2020, 10:34 AM	#16
Yellow 1 Grumpy Grey-haired Guy Drives: Camaro, Corvette & Merc C300(daily) Join Date: Aug 2014 Location: South Warwickshire, UK. Posts: 806 View My Garage	Probably easier to move state! You guys over there seem to have it worse than over here for modifications. Seriously though; long tubes for the win. __________________ ---------------------------------------------------------

04-06-2020, 03:56 PM	#15
Modernmusclecar Drives: 2011 Camaro SS Join Date: Jul 2019 Location: Parts unknown Posts: 820	Shorty headers with the Solo HI flow cats are the only way you will get a power increase. The stock cats are the major restriction point. If your an l99 get the Ls3 Solo hi flows the L99 have a connection to absorb vibration when the dod is active and they leak. The Ls3 is solid stainless body. The Jbas with the Solo hi flows don't need a tune...but on cars newer then 2011 I believe they tripped a cell and then you need extenders.

04-16-2020, 11:56 AM	#18
VR Baron SoCal Camaro5 Race Team Drives: 2021 Shadow Grey Camaro 2SS 1LE Join Date: Mar 2010 Location: SO CAL Posts: 14,288	In response to some saying shorties and hiflows make no power or little. As I posted earlier, at least if you get jba shorties and hiflows you get around 20, 11-12 from hiflows and 8-9 with shorties. That’s on a car with just cai and catback. A mild “smog” friendly tune is another 10-12. Three of us, two m6 and one l99, same dyno, modded as I said, all made 30-32 hp with tune. Tunes were 10-12 of that. Peak tq with tune is about 24. Would we prefer LTs here in Kali? Yes of course. A bit more power and they don’t fall off over 5500 rpm. But again in Kali, not a lot you can do