Shortened cat for extractors

DEVL-XR · 06-03-2007, 04:41 PM

I found some extractors at the wreakers for $120, there Pacemakers, not sure what model. I think they are light blue if that makes any difference.

Anyway this means I'll need my cat shortened to allow the extractors to fit, right.
I've looked into 2 options so far, buy the cat from the wreakers that is already connected to the extractors, $60.
Get my cat shortened by an exhaust centre, $70 approx.

High flow cats I think are a bit out of my price range ATM. There a few hundred aren't they?

Another option is if someone here has a cat to suit they can sell me cheap please PM me!

My main question here is it wise to get a cat from the wreakers? Or am I better off keeping mine and having it shortened?

Thanks
Braden

**Polyal** · 06-03-2007, 04:44 PM

High flow cats are not needed, about $70 for a modded cat and installation of extractors seems about right.

DEVL-XR · 06-03-2007, 04:46 PM

So you wouldnt recomend using the cat from the wreakers? Thats $70 just to mod the cat.

needaXYGT · 06-03-2007, 04:49 PM

nah id keep your cat mate!

Allen · 06-03-2007, 04:50 PM

Unless your cat is already stuffed, there isn't any gain from getting a hi flow cat...

IMO just have you existing cat modified to suit the extractors...

A high flow cat on a mild 4.0 is pointless... if it was heavily worked, that'd be a different story...

Oh, and good find on the pacemakers at the wreckers!

DEVL-XR · 06-03-2007, 04:59 PM

Yeah hi flows are out!

I'm not quite sure about the cat from the wreakers, it could be stuffed, bot sure how to tell.

As far as I know my cat is fine so I'm thinking thats my best option.

Thanks Allan, I was walking past and I seen them but I didnt register straight away, I was about 15 metres past it and I'm like, WOAH! Ran back and there they were!!

And finally if anyone has a shortened cat to suit cheaper than $70, preferably in Victoria than PM me!!

Psycho Chicken · 06-03-2007, 06:38 PM

A good cat will look like this inside.

A bad one won't.

DEVL-XR · 06-03-2007, 06:58 PM

Oooh very good Psycho Chicken! That helps heaps! I've tried looking in mine last time I had the exhaust disconnected but it was too dark under there! LOL!
If all goes to plan I'll get the extractors tomorrow so I might be able to check out the cat and judge it there.
Thanks.

XR_Lightning · 06-03-2007, 08:57 PM

just get the exhaust joint to modify your existing cat, and to be honest high-flow cats are a load of crap, believe it or not your cat is already high-flow (or has the potential to be), the element inside is exactly the same as it would be in a high-flow cat, the only difference being on a stock cat the pipe diameter goes from 2.5" to 2 1/4", but as soon as the cat is modified to fit extractors it will be high-flow because the 2 1/4 section wont be there anymore, and there is your high-flow cat for a quarter of the price

Also Braden the model of your extractors should be punched into the extractors and the date when they were made, just have a look between cylinder 1 & 2 outlets not on the pipe itself but on the flat piece that joint the pipes together

niko · 06-03-2007, 09:35 PM

have you looked at a standard replacement 2.5" cat to suit the performance setup?

Rollin · 06-03-2007, 10:53 PM

Save the cash up and do it right, it will only cost you an extra $60 or so.

Get the extractors, and if your cat is OK, use that. Get them to lop the ends off it so it is 2.5". If you cat is cactus, get the one from the wreckers.

You want the exhaust shop to fit the extractors, then run the longest piece of straight pipe possible between them and the cat - have the cat moved back as far as is practical to fit, then join it up to the rest of the exhaust.

By putting the cat as far back as possible, you preserve the high gas speed coming out of the extractors and into the exhaust, increasing their effectiveness, therefore (hopefully) increasing hp...

private9 · 06-03-2007, 11:37 PM

Quote:

Originally Posted by Rollin

Save the cash up and do it right, it will only cost you an extra $60 or so.

Get the extractors, and if your cat is OK, use that. Get them to lop the ends off it so it is 2.5". If you cat is cactus, get the one from the wreckers.

You want the exhaust shop to fit the extractors, then run the longest piece of straight pipe possible between them and the cat - have the cat moved back as far as is practical to fit, then join it up to the rest of the exhaust.

By putting the cat as far back as possible, you preserve the high gas speed coming out of the extractors and into the exhaust, increasing their effectiveness, therefore (hopefully) increasing hp...

The previous owner had done exactly this in my EL, the cat is just before the diff from memory. I had been wondering why this was done, thanks for clearing it up!

From what I understand though, moving the cat back means it doesn't get up to operating up to temp as quickly and therefore puts out more emissions as its warming and is therefore illegal. In theory exhausts are illegal too though, so doubt it really matters...

DEVL-XR · 07-03-2007, 02:27 AM

Quote:

Originally Posted by EB_Lightning

just get the exhaust joint to modify your existing cat, and to be honest high-flow cats are a load of crap, believe it or not your cat is already high-flow (or has the potential to be), the element inside is exactly the same as it would be in a high-flow cat, the only difference being on a stock cat the pipe diameter goes from 2.5" to 2 1/4", but as soon as the cat is modified to fit extractors it will be high-flow because the 2 1/4 section wont be there anymore, and there is your high-flow cat for a quarter of the price

Also Braden the model of your extractors should be punched into the extractors and the date when they were made, just have a look between cylinder 1 & 2 outlets not on the pipe itself but on the flat piece that joint the pipes together

Thanks for the info, I'll check the model number when I get them!

Quote:

Originally Posted by niko

have you looked at a standard replacement 2.5" cat to suit the performance setup?

To tell you the truth, No.

Quote:

Originally Posted by Rollin

Save the cash up and do it right, it will only cost you an extra $60 or so.

Get the extractors, and if your cat is OK, use that. Get them to lop the ends off it so it is 2.5". If you cat is cactus, get the one from the wreckers.

You want the exhaust shop to fit the extractors, then run the longest piece of straight pipe possible between them and the cat - have the cat moved back as far as is practical to fit, then join it up to the rest of the exhaust.

By putting the cat as far back as possible, you preserve the high gas speed coming out of the extractors and into the exhaust, increasing their effectiveness, therefore (hopefully) increasing hp...

Once I get the extractors I'll go and talk to the exhaust shop guy. I'll mention what you said, to me it sounds the best way to go.

Mickus · 07-03-2007, 02:38 AM

who you getting to go in and get them? lol. I'll come too. I want to see about those kick panels see if I can find them.

DEVL-XR · 07-03-2007, 08:20 AM

Quote:

Originally Posted by Mickus

who you getting to go in and get them? lol. I'll come too. I want to see about those kick panels see if I can find them.

;) Not here man!

mark_TD · 07-03-2007, 08:32 AM

I'm getting my full 21/2 sports exhaust on the EB today and I am using the same stock cat aswell and modifying it to suit the extractors. Use your cat as like you said the cat at the wreckers could be stuffed and you know the history of yours.
I will let you know how mine goes later today

eb91xr6 · 07-03-2007, 02:57 PM

who needs a cat just use pipe does the same job

crannersEL · 07-03-2007, 03:34 PM

I got my exhaust system and extractors fitted about 18 months ago, using the stock cat. It lasted me about 12 months until it started rattling which was the sign to get a new one, so i got a hi-flow cat fitted then.....

Your extractors will have a number on them, that will tell you if they are Std or Comps

Allen · 07-03-2007, 04:45 PM

Quote:

Originally Posted by eb91xr6

who needs a cat just use pipe does the same job

Got $10k?? :P

Quote:

Originally Posted by crannersEL

...It lasted me about 12 months until it started rattling which was the sign to get a new one.

Is it a kind of metallic rattling? I think that my cats (or at least the drivers side one) are stuffed, and they start rattling at around 2500rpm or when the engine is under heavy load...

niko · 07-03-2007, 05:42 PM

Quote:

Originally Posted by eb91xr6

who needs a cat just use pipe does the same job

ring the epa and tell them that you disagree with there rules...

gthofan · 07-03-2007, 06:29 PM

Quote:

Originally Posted by eb91xr6

who needs a cat just use pipe does the same job

my eyes hurt when i ran withought a cat for a while

:

nos_james · 07-03-2007, 06:57 PM

y would your eyes hurt i mean my xd doesnt have a cat. but you do need one if ya car came with one or look out for a big fine that and its better for the enviroment to have it

Allen · 07-03-2007, 07:02 PM

Perhaps it was being constantly on the lookout for the EPA...:P

Some people are more sensitive to carbon monoxide than others... When I go to the speedway races, the people I'm with whinge about methanol stinging their eyes, but it never effects me...

nos_james · 07-03-2007, 07:09 PM

mmmmmmmmmmmm i love the smell of nitro methanol does hurt ur eyes when there running rich tho lol

DEVL-XR · 07-03-2007, 07:28 PM

Picked up the extractors tonight, there Pacemaker 4499's. I wouldnt have a clue if that means there good ones or just average but they have to be better than the manifold!
I'll get them sandblasted and paint them matt black with hi temp.
I'll post pictures of them fitted, but for now heres a photo of them in my boot:

Allen · 07-03-2007, 07:33 PM

They look pretty damn good for a wrecker find!

Did the car they came off have anything else of intrest? If the former owner went to the trouble of have extractors fitted, who knows what else may be in it...

DEVL-XR · 07-03-2007, 07:37 PM

I think it's got the full 2.5" exhaust. I didnt bother taking the rocker cover off as the wreakers were closing just as I finished taking the extractors off. I wouldnt mind checking to see if its got a bigger cam tho.
How can I tell if its got a bigger cam?

crannersEL · 07-03-2007, 07:37 PM

Quote:

Originally Posted by fairlane_ghia

Got $10k?? :P

Is it a kind of metallic rattling? I think that my cats (or at least the drivers side one) are stuffed, and they start rattling at around 2500rpm or when the engine is under heavy load...

I heard the noice when i put the car into reverse and as the car slowly moved backwards, and it sounds like a ball bearing in a tin.

Allen · 07-03-2007, 07:43 PM

Quote:

Originally Posted by BradensEBxr6

How can I tell if its got a bigger cam?

Got a dial indicator and a lot of patience?? Measuring lobe lifts is easy, its the lobe angle seperation that is difficult to work out...
If its a reground cam, then the lobe lifts will be smaller than stock.

GTHOFAN may be able to give more information about it:P

Quote:

Originally Posted by crannersEL

I heard the noice when i put the car into reverse and as the car slowly moved backwards, and it sounds like a ball bearing in a tin.

Yep... ball bearing in a tin is a pretty acuarate description of what I've got... Funnily enough, my old NC made that noise on idle after I put the exhaust on it... I kicked the cat a few times and it went away :P

XR_Lightning · 07-03-2007, 08:25 PM

Quote:

Originally Posted by BradensEBxr6

I think it's got the full 2.5" exhaust. I didnt bother taking the rocker cover off as the wreakers were closing just as I finished taking the extractors off. I wouldnt mind checking to see if its got a bigger cam tho.
How can I tell if its got a bigger cam?

easiest way to check is to just pull out the cam and see if any id number/words are on the end of the cam, but its not always on there, and I dont think anything is imprinted onto regrinds