Going From A Gutted Cat To A Highflow

[WYTSKY]

Hey guys, so I fixed the problem of the flanges not connecting well resulting in a small leak.

Next thing is I have taken the car for a drive and noticed it is not as responsive/torquey as what it was with the stock cat gutted (simply it was a straight through pipe)

The only reason I got an Xforce highflow was because I was sick of constantly buffering the back of my car to get rid of the yellow residue of carbon monoxide that the cat would normally filter... but I did not want an extra restriction.

My current system is a 3' Xforce dump/front pipe, 3' Xforce highflow cat,

3' momocourse catback exhaust with a 5' tip

I know its probably almost impossible, but do you guys have any ideas how to make it as flowing as it was last time/even better?

Thanks for the help,

Adam

[R34GTFOUR]

  WYTSKY said:

I know its probably almost impossible, but do you guys have any ideas how to make it as flowing as it was last time/even better?

Thanks for the help,

Adam

correct o' mondo

obviously nothings going to flow as well as a straight through pipe, but there are different types of "hiflow" cats and some are not as good as others.

I've never dealt with xforce cats, but i use to have a 3inch hi flow cat (forgot the brand) in my old turbo fwd celica which was brand new and the car drove seemingly fine, but the best i could do was crack a 13.0 over the 1/4, so i was thinking of something simple to get me a 12s quarter mile. So i put a straight through pipe in and i noticed a difference, but unfortunately i never got it to the drags and sold it shorlty after haha

so in short, i would expect a lil drop

[subzeroR33]

I drilled a few holes in my cat. Its not fully gutted but enough for better flow.

Edited February 13, 2008 by subzeroR33

[WYTSKY]

hmm.... drilling holes... its just that I don't want that sh*tty yellow tinge to reapear...

I mean, maybe its in my head... one of these things flows at about 520 or something like that I read..I also remeber reading somewhere the racing spec ones flow at about 720ish? so would a straight pipe flow at a simple 1000??

Say I was to put the gutted cat back on, or drill holes in the current one, is there anything I can do to stop that yellow tinge?

I heard something like vaso or similar... but you don't really want to be cruising with that stuff on ur car.... any spray protectant?

Thanks,

Adam

[R31Nismoid]

Degreaser works a charm on the build-up once a week

[WYTSKY]

lol, sorry mate, spraying where exactly? cuz if its inside the cat I already lost half my thumb today take it off and on, so I don't want that happening every week!

[Craved]

  WYTSKY said:

lol, sorry mate, spraying where exactly? cuz if its inside the cat I already lost half my thumb today take it off and on, so I don't want that happening every week!

spraying on your rear bar then washing off to remove the stains from your rear bar

[WYTSKY]

ohh... check silly me, but I thought that degs was bad on paint you want to keep looking smick?

If one could extend their exhaust pipe slightly further then their rear bar would that help the problem?

[Craved]

  WYTSKY said:

ohh... check silly me, but I thought that degs was bad on paint you want to keep looking smick?

If one could extend their exhaust pipe slightly further then their rear bar would that help the problem?

heavily diluted degreaser - something like simple green with 1 :30 water mix is fine.

as for the pipe - it might, but i doubt you'll notice much difference since the terbulence at the rear of the car will always pull it back towards the rear bar to some extent.

[WYTSKY]

mmm... I thought as much, still was worth the question.....

so its either a degreeze/buff each week for the past 4 months with lots of flow and more power

or nice clean back with less flow and a fair bit less power...

OR possibly drill a few extra holes into the new cat for hopefully better flow without coughing out any carbon monoxide....(yellow tinge)

GRR... the choices...

[R31Nismoid]

You dont wash your car once a week? or even once a fortnight?

Would add maybe, 3-4mins to the job overall

Suppose if you didnt then yeah, going the legal way would be besy

A hi-flow cat really wont require 'holes' if its a decent flowing one (3.5" metal cat or something)

[subzeroR33]

Even with a cat you will get the shit on ur rear bar.

[WYTSKY]

lol, ofcourse I do I don't know what colour car you have, but my white one collects enough in a week/5 days to cover 3/4 of the rear bar.

I will try the degreaser though just gotta wait till my thumb heals to put the stock cat back on and go down to the car wash!

Subzeror33: I truely hope not, cuz then I got this cat for nuthing!

[subzeroR33]

Sorry mate that is the nature of the RBs nice and rich. I have the same problem with mine you just live with it.

[WYTSKY]

but before, when my stock cat was normal I never had a problem, as soon as it was gutted I started noticing the yellow. does a highflow not do as gooder job filtering the carbon monoxide as a normal cat?

[bubba]

I have one of those 3" Xforce cats, they suck. I only use it for going over the pits

[_Ryan_]

570CFM...

Ash, i wash my car maybe once per month lol.

Why have the tip aiming downwards? mate's tip on his 1600 dumps, and his anus doesnt have the black tinge of mine.

[R31Nismoid]

  subzeroR33 said:

Sorry mate that is the nature of the RBs nice and rich. I have the same problem with mine you just live with it.

You mean it’s the nature of POORLY or UNTUNED RB's to run rich.

RB's with in a decent state of tune do not do this

[silva33]

I have had no cat in 3 different performance turbo cars, and as ash states, it isnt that much, just a little degreaser and she is all clean again.

If you are getting 3/4 of your bar with the burnt gold look then there is something wrong with your tune!

[ZENNON]

i wouldn't recommend drilling holes - thats dodgy

either do this

(also not really recommended for skyline IMO)

of get a bigger and better flowing cat