any gains from removal of 1st pre cat 99 max?
#1
any gains from removal of 1st pre cat 99 max?
ive wondered for a while if i would gain any hp by having a pipe made to replace the first pre cat on my 99 cali spec max..my ypipe does not replace this part of my exhaust i notice while browsing the Stealin catologue today that there y pipe has an extra pipe to replace that piece also anyone know?
#5
Someone did this awhile back....desertmax or something....anyway he switched out his cali-spec y-pipe and exhaust manifold for a fed spec y-pipe and manifold. The gains were minimal.
However, he did get rid of the front pre-cat and probably shed a few pounds off his car by doing so. He had a nice side by side comparison of the two setups and the fed-spec one looked pretty good. He had to relocate an O2 sensor by drilling an extra hole in the y-pipe (I think?) to fool the ECU into thinking the precat was still there. Something like that...
Anyway, I wish I could find the site...it was a good write up.
However, he did get rid of the front pre-cat and probably shed a few pounds off his car by doing so. He had a nice side by side comparison of the two setups and the fed-spec one looked pretty good. He had to relocate an O2 sensor by drilling an extra hole in the y-pipe (I think?) to fool the ECU into thinking the precat was still there. Something like that...
Anyway, I wish I could find the site...it was a good write up.
#6
Originally posted by sbslacker
Someone did this awhile back....desertmax or something....anyway he switched out his cali-spec y-pipe and exhaust manifold for a fed spec y-pipe and manifold. The gains were minimal.
However, he did get rid of the front pre-cat and probably shed a few pounds off his car by doing so. He had a nice side by side comparison of the two setups and the fed-spec one looked pretty good. He had to relocate an O2 sensor by drilling an extra hole in the y-pipe (I think?) to fool the ECU into thinking the precat was still there. Something like that...
Anyway, I wish I could find the site...it was a good write up.
Someone did this awhile back....desertmax or something....anyway he switched out his cali-spec y-pipe and exhaust manifold for a fed spec y-pipe and manifold. The gains were minimal.
However, he did get rid of the front pre-cat and probably shed a few pounds off his car by doing so. He had a nice side by side comparison of the two setups and the fed-spec one looked pretty good. He had to relocate an O2 sensor by drilling an extra hole in the y-pipe (I think?) to fool the ECU into thinking the precat was still there. Something like that...
Anyway, I wish I could find the site...it was a good write up.
#7
He did the swap and gained alittle more midrange torque without the precat.
http://forums.maxima.org/showthread....ifold+AND+swap
http://www.desertpearlmax.homestead....noResults.html
http://forums.maxima.org/showthread....ifold+AND+swap
http://www.desertpearlmax.homestead....noResults.html
#8
Member who somehow became The President of The SE-L Club
iTrader: (19)
Join Date: Jun 2001
Posts: 16,033
It does not throw a CEL, the pipe is made so that the sensor that looks at the first pre cat is moved and looks at the 2nd remaining cat. The ECU has no idea which cat it's looking at, all it sees is a working cat so it things all is OK. Both pre cat o2 sensors remain on the car to monitor the a/f ratio of the front and rear cylinder banks.
Gains for us Cali Spec cars are in the range of 8 - 10 HP, not 15 - 18 like you Fed spec guys. It's still a very good bang for the buck mod.
Quick Note: I just put the Injen intake on my Cali Spec and the DynoButt feels better pull in the mid range area. Nothing lost down low, and a really nice roar at WOT! Combine an intak with a Y pipe and our Cali Spec Max's run pretty damn quick too!
Gains for us Cali Spec cars are in the range of 8 - 10 HP, not 15 - 18 like you Fed spec guys. It's still a very good bang for the buck mod.
Quick Note: I just put the Injen intake on my Cali Spec and the DynoButt feels better pull in the mid range area. Nothing lost down low, and a really nice roar at WOT! Combine an intak with a Y pipe and our Cali Spec Max's run pretty damn quick too!
#10
Member who somehow became The President of The SE-L Club
iTrader: (19)
Join Date: Jun 2001
Posts: 16,033
Originally posted by 99maximagxe
I thought budget released their new cali spec y pipes with the extra piping any owners have this yet?
I thought budget released their new cali spec y pipes with the extra piping any owners have this yet?
#11
Supporting Maxima.org Member
iTrader: (8)
Join Date: Apr 2003
Location: Shippensburg, PA
Posts: 1,781
so a y-pipe is worht it then? I wasn't really into getting one casue of the cat that coulden't be removed.
wish headers would come out with holes for the sensors. What about swapping the ECU also?
wish headers would come out with holes for the sensors. What about swapping the ECU also?
#12
Originally posted by Maxtank
so a y-pipe is worht it then? I wasn't really into getting one casue of the cat that coulden't be removed.
wish headers would come out with holes for the sensors. What about swapping the ECU also?
so a y-pipe is worht it then? I wasn't really into getting one casue of the cat that coulden't be removed.
wish headers would come out with holes for the sensors. What about swapping the ECU also?
Thread
Thread Starter
Forum
Replies
Last Post
The Frye
7th Generation Maxima (2009-2015)
6
09-02-2021 11:03 AM
MaxLife17
8th Generation Maxima (2016-)
43
06-27-2019 01:37 PM
Justin Kroll
5th Generation Maxima (2000-2003)
7
09-02-2015 11:06 AM