After much deliberation and a little prodding I've decided to gut my cats in the morning. I've been a little disapointed with the to end performance lately, and hope this will help.
Has anyone else done this? What were the results?
After much deliberation and a little prodding I've decided to gut my cats in the morning. I've been a little disapointed with the to end performance lately, and hope this will help.
Has anyone else done this? What were the results?
No more trucks, but this is what I used to have. 2000 GMC Sierra, 6.0L-LQ4, Built 4L60, LS6 Cam, The Other Guys Headers, 3 inch exhaust and 7 chamber flowmaster, 43lb injectors, Nelson Tuning, Drop - 3/4 McGaughys Spindles, Bell Tech Shackles & Hangers. Best time 13.59 @ 106
i cut them out entirely
top end baby,
, just ask allen(dude has probably tuned thousands of trucks by now, would be humbled if he could remember mine!
, my truck is loud as hell! she pulled to 133 and i backed off (not much left aneways)cause our turn was coming up!
kill the cats man, they are in your way
Yeah I cut mine out entirely too, the top end absolutely rocks! The sounds is awesome with my 50 series dual in/dual out flow!
Chris
2009 Silverado, HPTuners, all stock.
Well my story is not a common one.... My cats were CLOGGED...
I took them off and then went to the dyno and gained
22rwhp and 27ftlb
I think Allen had the same issue with clogged cats awhile back.
Chris
2009 Silverado, HPTuners, all stock.
Will it still pass emissions? LOL What about engine light coming on?
99 Pewter SCSB
DJM 4/6 drop, Hotchkis front/reat swaybars,Hypertech power programer, milled & built heads, Accel wires, distributer,coil, Mass Air Flow Sensor(mti motor sports, Granatelli),Dynomax UltraFlow Stainless, 17x8.5 Eagle Alloys, Escalade door handles, Suburban front grille, with clear corners and billet bowtie,Street Scene mirrors, Cowl Hood
You'll REALLY have to know how to tune it to get it to pass the sniffer being catless. Need a cam that'll self EGR, etc.
With FI I'd expect some pretty pronounced gains dumping the cats, but ditch that Flowmaster for a muffler that has some flow. I've seen people lose 1-1.5psi as they have so much backpressure.
Also on an N/A app someone I know picked up 0.2 in the 1/8th with LTs by going to a straight through design muffler... that's 0.31 in the 1/4 from just a muffler.
The superior man is modest in his speech, but exceeds in his actions. - Confucius
"He who asks of life nothing but the improvement of his own nature, is less liable than anyone else to miss and waste life."- Henri Frederic Amiel
'01 Chev Z71 LT - '85 BMW 745i TURBO - '88 BMW 750iL - '88 Ford F150 XLT Lariat - '79 MB 240D - '79 MB 280S Euro
'80 MB 380SE-5.0 Euro - '85 MB 300SD - '87 MB 300SDL - 1990 MB 300SEL - '91 MB 300SE - '91 MB 560SEL
Let's face it, the red hair... makes 'em wet.
Just slip someone a 20 and it passes man!if not just keep goin out with the 20$, it will pass!, or, find a "freindly" inspection station(by that I mean one that dont give a fuck)
unless you are from california, then you are just S.O.L. ! , as Far as the Light goes, send the PCM back to allen, he can "fix that",
The cats are out!!!
The sound is much better. I haven't had any road test time yet, but I'm sure I'll get some later this evening.
No more trucks, but this is what I used to have. 2000 GMC Sierra, 6.0L-LQ4, Built 4L60, LS6 Cam, The Other Guys Headers, 3 inch exhaust and 7 chamber flowmaster, 43lb injectors, Nelson Tuning, Drop - 3/4 McGaughys Spindles, Bell Tech Shackles & Hangers. Best time 13.59 @ 106
how bout a sound clip
old mod list: H/C/I/N/E/G 408
new mod list: 5.3, gears/posi, mufler and tune : (
Posting Permissions
Reply With Quote
