Notices
Intake Exhaust Moving all that air in and out efficiently

Anyone dyno w/ gutted stock cats?

Thread Tools
 
Search this Thread
 
Old 02-05-2008, 10:58 AM
  #21  
Jeff92se
New Member
iTrader: (4)
 
Jeff92se's Avatar
 
Join Date: Apr 2005
Location: nw
Posts: 43,680
Received 1,072 Likes on 964 Posts
Default

Yeah but could you stand the rasp for the few hp gains? If one could gut and then weld in some straight pipes inside to make function like TPs, that might work.
Old 02-06-2008, 05:41 AM
  #22  
gothchick
Registered User
iTrader: (12)
 
gothchick's Avatar
 
Join Date: Feb 2007
Location: ATL
Posts: 3,300
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by KCMO_HR_G
I have an '08 G35.

Thanks for the ignorant response and not reading a single one of my comments about why i'm considering this route.

dumb flaming trolls are worse than ricers IMO.
If you truely have an '08, then please trade it back in. Anyone who is ignorant enough to even consider hacking up the cats on a brand new car doesn't deserve it.
Old 02-06-2008, 07:06 AM
  #23  
1nate7
Registered User
iTrader: (19)
 
1nate7's Avatar
 
Join Date: Apr 2003
Location: Tucson
Posts: 1,116
Likes: 0
Received 0 Likes on 0 Posts
Default

Doesn't anyone actually read the thread anymore? He has an extra set of cats to gut and wants to look stock. What a ricer, he wants to look stock and gain power.

Sorry I can't help you out with before and after dyno plots. I would go for it though, you don't have much to lose. As far as the rasp, I doubt there will be any with a stock G35 sedan exhaust.
Old 02-06-2008, 07:43 AM
  #24  
T_K
Registered User
iTrader: (5)
 
T_K's Avatar
 
Join Date: Jul 2007
Location: Chicago
Posts: 870
Likes: 0
Received 2 Likes on 2 Posts
Default

Originally Posted by KCMO_HR_G
It just seems like the cat material and expansion into the cat filled chamber would slow down velocity more than having the large open space. At least you understand my primary concern... I should have just stayed on KCSR and debated this between the 2 of us
Despite some good points being made based on exhaust theory, what anyone can tell you at this point is just speculation. Due to the restrictive nature of the stock cats, better than older OEM cats, but still fairly restrictive, by removing all the innards you're going to gain CFM thats a given. CFM alone won't determine the effects on exhaust velocity, but it will flow better in the upper RPMs. I'd venture a guess and say you'd gain about the same numbers as test pipes above 5000 rpm. Below 5000 rpm, worst case scenario you lose a little bit of torque, best case scenario you don't. Even if you lose the low end, the overall result is going to be a faster car if thats the goal you're aiming for. If you already have the extra set of cats acquired for cheap, what have you got to lose?

TK
Old 02-06-2008, 07:55 AM
  #25  
Hydrazine
MOTORDYNE-MY350Z SPONSOR
iTrader: (53)
 
Hydrazine's Avatar
 
Join Date: Jul 2004
Location: L.A. California
Posts: 4,399
Likes: 0
Received 9 Likes on 4 Posts
Default

Anyone:

Send me your gutted cats and I'll trade you a set of strup test pipes for them.

I will dyno the gutted cats against regular test pipes. Same day, same everything.
Old 02-06-2008, 08:59 AM
  #26  
Get_Zwole
Registered User
iTrader: (34)
 
Get_Zwole's Avatar
 
Join Date: Mar 2007
Location: oklahoma city
Posts: 7,908
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Hydrazine
Anyone:

Send me your gutted cats and I'll trade you a set of strup test pipes for them.

I will dyno the gutted cats against regular test pipes. Same day, same everything.
cant beat a deal like that
Old 02-06-2008, 09:34 AM
  #27  
Jeff92se
New Member
iTrader: (4)
 
Jeff92se's Avatar
 
Join Date: Apr 2005
Location: nw
Posts: 43,680
Received 1,072 Likes on 964 Posts
Default

Is it worth the noise though. Those hollow cans have to be resonating monstors when gutted.

Originally Posted by T_K
Despite some good points being made based on exhaust theory, what anyone can tell you at this point is just speculation. Due to the restrictive nature of the stock cats, better than older OEM cats, but still fairly restrictive, by removing all the innards you're going to gain CFM thats a given. CFM alone won't determine the effects on exhaust velocity, but it will flow better in the upper RPMs. I'd venture a guess and say you'd gain about the same numbers as test pipes above 5000 rpm. Below 5000 rpm, worst case scenario you lose a little bit of torque, best case scenario you don't. Even if you lose the low end, the overall result is going to be a faster car if thats the goal you're aiming for. If you already have the extra set of cats acquired for cheap, what have you got to lose?

TK
Old 02-10-2008, 01:08 AM
  #28  
shiftdrift06
New Member
iTrader: (24)
 
shiftdrift06's Avatar
 
Join Date: Nov 2007
Location: Htown
Posts: 490
Received 1 Like on 1 Post
Default

Originally Posted by gothchick
+1.

As used Z's become older & less expensive, the younger ricer crowd grows in numbers, desecrating our precious Z. I wonder if the OP has an x02 anywhere on his Z to compliment his gutted cats? FTL.
Rice eh? I looked at your signature and seen "Coming soon: Nismo license plate frame"


If you have an extra set. You don't have anything to lose. Sure they cost soo much from the dealership. But on the board you will find them for MUCH LESS then that. Hell, I got mines for 60shipped.

Personally, I would rather have gutted cats. There more durable then most aftermarket brands. Keeps your car "stock", giving you less hassle from the cops and inspection. Also, its free. Just takes alittle time.

Yea, there not straight through design, but is it really gonna effect it THAT much. Would you say to buy an X brand TP to only gain a small amount of power over gutted cats? But in return you do lose the factors I stated earlier of gutted cats.


I guess its down to personal preference. Some people say "why don't you just buy TP,HFC,etc..."
I say why do that when you can gut your cats, and save some money for bigger mods.
Old 02-10-2008, 08:42 AM
  #29  
Dave B
Registered User
iTrader: (2)
 
Dave B's Avatar
 
Join Date: Jan 2005
Location: Shawnee, KS
Posts: 308
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by shiftdrift06
Personally, I would rather have gutted cats. There more durable then most aftermarket brands. Keeps your car "stock", giving you less hassle from the cops and inspection. Also, its free. Just takes alittle time.
The thin walls of the OEM cat housing will be freaking loud. The cat material serves as a muffler. Without it, the noise will be nasty.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
seagrasser
Zs & Gs For Sale
6
10-11-2015 03:27 PM
NissanZcrazy
Forced Induction
4
09-23-2015 07:59 AM



Quick Reply: Anyone dyno w/ gutted stock cats?



All times are GMT -8. The time now is 12:12 PM.