I'll post some pics and maybe later tomorrow try that sound clip thing out...last time I tried I got my a$$ kicked trying to edit the darn thing.....later it's fight nite!!!!!!!!!

 

I have 2.5 on my 3.0L now, the top end gains from changing everything was insane but i removed 3 cats and increase from stock diameter. i think backpressure and low end loss from 2.5 to 3 would be almost nonexsistant. i noticed a loss in low end but i raised diameter and pulled out 3 restrictions it didn't drop terriblly.. a .5 inch increase from catback wont lose that much more backpressure however im skeptical of gains being great on the 3.0L ... i would definately go 3 on the 3.5L though.

just my 2 cents since i did full exhaust at once and didn't notice HUGE backpressure/lowend loss

 

Here's some picture after the install of my 3" CM catback...Had the most difficult time adjusted the rear slip on fit clamp for proper clearance thru rear end suspension supports......


Here's a comparison shot of my 3 B-pipes, Oem vs 2.5" CM vs 3" CM


Check out my solution for reducing exhaust side to side motion


Check out my clearances no adjustments needed plenty of room with braces

 

Continued...Here are my reuseable Oem cat gaskets being compared to the CM 3" gaskets....Will need to diegrind I.D. of gasket to fit 3" exhaust perfectly....




Rear view of tips


Rear mufflers assembly comparison...Was running CM 2.5" bpipe w/Oem rear muffler....


I was again pleased with the overall fitment of the CM 3" catback system....Thank god for that slip fit joint. It allows you variably position the muffler/exhaust to clear suspension brackets. Once I installed it and never had to make any other adjustment after my 10 mile test ride. The weather was wet so everytime I'd mash the throttle 3/4 the way to the floor even at 40-45 mph the tires broke loose. It appears to be a keeper so far guys....thanks again for the awesome product Brain.....

 

Hmmm... Debating should i get a 3inch setup or 2.5 , the decision, the decision...UGH only thing is i dont have a 3.5 so im leanin towards an 2.5 , but im puttin on SC soon so idk ...

 

If you're going F/I soon, then it should be a no brainer on the 3"

 

but would it really be a bigger diff. then a 2.5 ??? just curious

 

Yes on a supercharged 3.0 I would bet on 15-20whp difference at least, maybe a lot more at high boost (small pulley)

 

Hey as an experiment reinstall your Oem rear muffler section, you will have to mod the flange slightly but if you have a dremel or diegrinder it can be modded in about 15-30 minutes. The driveabilty will be very much like stock until you step in too it pass 1/2 throttle then it will change personalities and hand you a hell of a punch from midrange on up!!! Guaranteed!!!! So just for your info...
When my 03 was running the Cattman Ypipe and Cattman 2.5" catback I didn't lose any bottomend and the car was barely slightly louder than stock...but the part throttle tractabilty was not as crisp compared to the Oem rear muffler when installed with this same setup! Try it you might like it!

 

My wife just commented that the 3" exhaust is so loud she can't think! Oh boy, here we go....kinda what I anticipated...I'm trying to move her to drive the 3rd Gen to work instead, since it's still really quiet ( for now)! But she loved that 2.5" bpipe and oem rear muffler setup....so I'll definitely will be trying to get the dynamat crap rolling real soon, as well as the cone insert.....stay tuned!!!!!!

 

Just get her some earplugs! She'll be ok. Ah the joys of marriage. Finally got my wife to drive the truck so she doesn't bother me about messing with the maxima. Still I think it's time to move on soon to something domestic, rwd, 8 slugs, and maybe OEM FI.

 

So are you going to have these cone inserts welded in? Hopefully the "claims" of no power loss are true, or you'd be in essence wasting a lot of money on a 3" that no longer performs like a 3", lol. Throw that in with adding some dynamat weight and maybe you can get it to perform something like with the OEM muffler!

 

No welding needed, and, dynamat is only applied to the spare tire recess(bass Drum) and trunk floor above rear muffler 8 sq. ft. That's nothing! The Insert claims 1-2 horsepower loss.... I'll try it...IF I HAVE TOO!!!! Other than that...It's really tolerable...I find it to be quieter and deeper than the 2.5" catback when equipped with headers....As far as it performing like an Oem muffler....Mine performed great at the track and in keeping this car very civil/comfy/quiet/but sleeper fast ...So whatever you're tallking about isn't the case here....there won't be even 8 lbs of dynamat applied to my ride and that insert isn't killing performance like you think it is....

 

Oh I was just speculating, mainly to push your buttons and get an emotional response like in previous instances.

In any case, I'd have to see proof either way on the cones. Considering how little it takes to cause flow restrictions by redirecting the flow and causing turbulence, I'd be slightly worried without researching. Obviously I didn't research them but you probably have.

Although, the worst case scenario is that they do create a restriction and you gain some low throttle power, which is where all the fun is. Just the thought of that sheer rush experienced at 20% throttle above 2500 rpms makes me quiver with excitement.

 

Oh.........really...............................?

 

Brotha I appreciate it mr. catts got ahold of me today. went on and dropped 500 for my security deposit just waiting on him to charge it.

next is intake spacers to go with the SSIM, and then with a ts reflash and afc ill be done with the max

will do the glassing and audio work in a week or so when i get home on leave.

 

Just ordered my Headers, Fastcat, and 3" Catback. WOOOOO!!!!

 

Lucky big spender!! Good choice.....

 

Yeah, I did pretty good on my DAT, so my wife's lettin' me reward myself.

 

I just did the same today Took a good chunk from my tax return check though

 

All 3 of those mods at once, you'll definitely feel a huge difference on start-up. GL!

 

hmmmm...asked him to charge 5, he only charged 222 lol...oh well.

 

Nice Doug! Glad you got to pick one up. They're very good quality, I'm sure you'll enjoy it.

 

Sorry about that, I just sent you an email...

 

Ran my car down At the track and didn't quite get what I wanted with my 3" but had some blown engines and oiled track...had great R/T on both runs .198 and .168....but lousy 60 Ft times 2.247 and 2.325 (oil on track) and stomped didn't powerbrake...I usually run in the 2.1's w/o ES MM but w/Illuminas....I have ES MM w/Illuminas now and I'll need to work on my 60ft....my previous best with an Injen Intake and 2.5" bpipe and Oem Rear muffler was 14.6 @ 94 mph with a 2.194 60ft....If I can get my 60ft down to 1.8-2.0 then I'll be around 100-102 trapspeed no doubt...I'll work on my powerbraking and try to beat this sissy a$$ 14.5@ 95.01 mph 1/4 mi. The car is pulling really good but an automatic can't make it's speed back up as fast as a manual can if the launch was screwed.....

 

R/T has absolutely no bearing on your ET

Take a look at these bad R/Ts.... It's all about the launch, screw worrying about the lights, just launch good.

Also, '60 foot time doesn't have too much to do with your trap speed. That's mainly power and shifting... You won't run faster than a 2.0 '60 on street tires unless you get amazingly lucky for some reason, you'll want some smaller diameter sticky tires to get sub 2.0s.




Just for proof on the trap speed. Look at this one, it's higher than the 1.83 '60 foot trap speed...

 

Somewhere in the content, I think he swapped RT & 60'. But yes, as we've been saying for a decades now, RT = nothing to do w/ ET.

I've seen 17 second RT's with 13 second ET's.

 

Sorry Sparks I meant 60 ft times...I think you know that when I mentioned 1.8-2.0 sec range, but yeah you're right they have no bearing on 1/4 times....Where've u been Nmex in jail or out the country????LoL

 

County .. haha. They let me out of my cage.

 

Yeah I picked that up, which is why I said this then showed proof that '60 foot doesn't have much of an effect on trap speed:

"Also, '60 foot time doesn't have too much to do with your trap speed. That's mainly power and shifting... You won't run faster than a 2.0 '60 on street tires unless you get amazingly lucky for some reason, you'll want some smaller diameter sticky tires to get sub 2.0s."

And yes, autos suffer from shift time problems too. Do you have DR mod, suprastick, modded VB, anything like that? There's definitely more to your low trap speed than your launch.

 

Yeah Didn't I mention an oily track? I've tested my trap speed on my public section of road that's been marked and measured with no intrusive traffic (it's just straight, no ajoined streets nor driveways nothing)and is very safe to test on...along with my Gtech and I've trapped over 100 before....And 60 ft times are directly proportional to your trapspeed...Just read your own slips......

 

Let's do that, why don't we?

1.995 '60 foot


1.830 '60 foot



Here are some from last track day at coastal plains:
'60 foot 2.24
ET 13.64
MPH 104.36

'60 foot 2.63
ET 14.02
MPH 104.48


Now how about a different car? 2008 Cobalt SS turbo, pulled from slips where he lined up next to me:
'60 2.55
ET 14.05
MPH 112.31

'60 2.12
ET 13.06
MPH 112.52


Just wait till NmexMAX gets back in here and confirms what I am saying, we were just having a similar conversation in my thread in the drag racing section.

Seriously though I'm probably wrong, I know you're a guru on the subject and all.

 

I was here .. saw it and thought .. man here we go again.


BTW, got sound clips? Under load and otherwise?

 

Trap speed is basically your horsepower, reaction times have nothing to do with ET or trap speed and a poor 60' time has more to do with ET than what you trap.

14.5 @ 95 for a four door family car with an automatic isn't bad anyway.

Best gains I ever got with regards to trap speed with a single mod is with my old Chevelle when I went from a Carter 625 carb to a Holley 650 double pumper. Running horrible 2.56 gears at the time and going through the traps in 2nd gear. Went from a 14.8 @ 96 to a 14.68 @ 100 mph. 4 mph improvement in trap speed is a pretty decent gain. Probably could have run even better, but I dialed a 14.65 and ran a 14.63 at 93 on the brakes. If I'd have known I was going to break, I would have stayed in it. Pretty sure it would have been in the 14.4 range at 101. Last time I ran with those gears, next time out I had a 3.08 rearend with posi.

 

Here they go at it again.... lol.

 

Yep, here we go....sorry I reworded my statement I meant 60 ft....but anyway bottomline is getting my rpm's up out the hole will help me farther down the track....until then I'll have to learn to shift this A/T manually once the TS reflash is done I can hold my gears a little longer all the way to the 7100 redline....Even shifting @ 7000 rpm would be more beneficial than 6600 rpm once flashed...and maybe even letting it shift itself will be better with the remapped fuel and ignition than what I presently have.....really trying to avoid the SAFC/VAFC unless I choose too!!!

 

Have you done your block plate yet? I know it automatically made my transmission shift at a higher rpm than before it was installed. I don't know what affect the reflash might have, not sure the TCM will allow the transmission to shift beyond the factory redline but until then, the block plate ought to put you right up near redline on upshifts without having to manually shift until you get the reflash. Just one less thing to worry about while trying to get the best ET possible. As it is though, with a 95 mph trap, mid 14s is about as good as it gets.

 

I'd like to order one.

 

Yeah! I just did my block plate yesterday, and I have a 4AT... I noticed that it was shifting closer to redline at WOT. Before, it would shift well below 6500 (redline), now it almost hits 6500 before shifting... I'm gonna test it again today and get exact numbers

 

Is this one with the resonator or without??