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-   -   can muffler shops make this??? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/can-muffler-shops-make-206629/)

Castrol86GXL 07-18-03 01:02 PM

can muffler shops make this???
 
on another forum a LONG time ago a guy said if a muffler shop wont make you a straight piece of pipe to remove the cats that tell them the size of the pipe you want and the flange size and they'll make you one??? now im just curious because theres someone i want to do this for me but its a private owned shop and hes kinda iffy. how much should something like this cost so i dont get ripped?

Cosmo Donk 07-18-03 01:12 PM

Don't tell them anything:) Meausre it yourself and then go there and tell them to stick on two flanges and then mushroom the ends so the flanges stay on. Easier thatnwelding the flanges. Only goofy part might be that the FC cat has an angled flange.

If they ask, it's for you everglades swamp boat:)

Also, it should only be $50 max unless they use titanuim:)

Castrol86GXL 07-18-03 01:13 PM

usually ice is the first to reply to my threads and not even the modification master cake??? hmmm i guess my threads are lame

Cosmo Donk 07-18-03 01:14 PM

I beat them all to it! I am the MASTER! *insert He-man music*

Castrol86GXL 07-18-03 01:16 PM

dould post

Castrol86GXL 07-18-03 01:17 PM

wont that mushrooming create an exhaust leak at all??? and muffler shops can bend pipe cant they??? also how would you meause that??? with the bend in it? will the exhaust hangers give enough leway if i dont measure perfect???

Cosmo Donk 07-18-03 01:18 PM

Ehh.. If the flange is strong and you put a gasket in there it should work fine. As long as it lines up nice. If the straight pipe is the same size you can just chop off the ends of the cat, if you don't need them, and just tell them to weld it on to some pipe:)

Yes, most can crush bend but not mandrel bend. Small crush bends will not hurt flow that much.

Cosmo Donk 07-18-03 01:20 PM

Ok, wait a sec here. Are you also talking about a downpipe to replace the pre-cat?? Also I see you have an NA:) heh. Ok, so you want a single piece of pipe going from the header all the way to the y-pipe?

If so it will be a tough thing to do without having the car in the shop.

Castrol86GXL 07-18-03 01:21 PM

its just more of my stuff was original and ive had some problems getting under my 2 inch high rx7 with only a small jack and trying to get those stupid bolts off. and i cant wait for soaking the bolts either i dont have an airpump right now, took it off yesterday and i need to remove my cats, but i dont wat to do the ghetto gutting

Castrol86GXL 07-18-03 01:24 PM


Originally posted by Cosmo Donk
Ok, so you want a single piece of pipe going from the header all the way to the y-pipe?

well i want it from the begginging of the first precat to the end of the main cat, i was just thinking of hacksawing off the flanges from the ends of both sides and telling them to make a piece from the middle (of course with the correct size) it that a really hard thing for them to do???

Castrol86GXL 07-18-03 01:35 PM

also no one ever told me how much something like this might cost.

Cosmo Donk 07-18-03 01:45 PM

So if I am understanding this right.

You want something that looks like this??
GRRRR. POS new server!

Try this:
http://216.67.243.52/~rx7turbo/arturo/downpipe1.jpg

ilike2eatricers 07-18-03 01:47 PM

link doesnt seem to work for me

Castrol86GXL 07-18-03 02:10 PM

yes thats what i want, can i just get one made?

Cosmo Donk 07-18-03 02:18 PM

Yes but they need to be bent to the right shape. It is a trial and error thing. If you don't mind, or can, drive back and forth just have them bend it close to what you think you need and then try, then bend, then try.

Castrol86GXL 07-18-03 02:21 PM

well he'll work with incentive ($20) or so, i was just wondering how much something like would cost too

Cosmo Donk 07-18-03 02:23 PM

Pipe = $30
Bending = $Whatever he feels like charging
Flange = $8
"Incentive" = $20;)

Icemark 07-18-03 10:14 PM


Originally posted by Castrol86GXL
usually ice is the first to reply to my threads and not even the modification master cake??? hmmm i guess my threads are lame
I have been out of town most of the week, and I am against any removal of the stock emissions system, so that the car will not pass emissions testing.

Black13B 07-18-03 10:16 PM


Originally posted by Icemark
I am against any removal of the stock emissions system, so that the car will not pass emissions testing.
Why is this? :scratch: (aside from the obvious..)

Just have a strong feeling on the issue, or?

Bruce 07-18-03 10:40 PM

racing beat already makes that pipe your looking for. I would try there first but if you insist, when you go to the muffler shop ask them to make you a test pipe, just tell them its for when you race at the track/

Black13B 07-18-03 10:44 PM

castrol, are you getting this pipe for your GXL? this picture Cosmo Donk showed you is one for a turbo model.. :)

Icemark 07-18-03 10:55 PM


Originally posted by Black13B
Why is this? :scratch: (aside from the obvious..)

Just have a strong feeling on the issue, or?

Okay, the world as per Mark:

I personally believe that you can have healthy decent power on a street driven, street legal car without removing the emissions.

Take my 13BT swap into my 'vert. I swappped so that the engine (technically an option as far as CARB is concerned) retained all the emissions equippment and still had in the easy neighborhood of 200-220 HP. Everything works perfect and the car is as clean as it should be.

But the lame in-experienced owner, what is the first thing he wants to do??? rip out the cat, throw away the air pump, etc. What is up with that??? All to get a few extra HP??? I have seen how the stringent air quality controls on factories and cars has done a major job cleaning the air in California. I have seen the air quality go from, " hell no way I am driving in LA today" 100 times a year done to less than 20. Emission controls work and frankly there are few things worse than crusing down the nice twisty road withthe roof open (or down in the case of 'vert owners) following some numb nuts who pulled his cat and gagging on his exhaust fumes so that he can have an extra 10 HP.

But the biggest idea left over from the 70's was that removing all the federal mandated emissons restrictions will give you a ton of power.

Lets look at a S4 N/A car, for example: You start in the neighborhood of 140-150 FWHP. Cat back and high flow air filter, and you are typically up another 10 to 20 HP. Upgrade to a mild polished S5 upper and middle intake, and other minor tweeks, and you are up another 10-15 HP.

That puts you at stock S4 T2 power and still emissions legal.

Maybe you say, that's not enough. I must have more HP... well why didn't you buy a car with the HP you must have in the first place??? If you want 200 HP, why didn't you buy a Turbo??? I mean come on, is your decision process that flawed, that you couldn't buy what you really wanted in the first place?

Okay, so you wanted the HP after the fact. Then do the swap... It'll get you that same HP range for less than $1000 (much less on average) if you do the work yourself and sell your old parts. But bolt on the factory emissions and keep the car and the air/world around you clean.

Ian Wilkshire also had a great thing to say about cats in his treaty on exhausts:

After this it is slowed by a device so despicable I can barely frame my mouth to speak its name.cat. catalytter. You know that THING.

I despise it and the dreadful environmental damage it wreaks.

What it does and how it does it is (chemically) one of the most beautiful of natures tricks.

Catalysis is stunning, we have seen it and used it for over 100 years but until Richard Feynman (him again) described what really happened in the process in the 50's we were at a loss to explain it. His theoretical hypothesis was only proved true in the late 80's by the use of an exceptionally powerful 'live' Electron Microscope. What we saw that great day was so perfect that the images will remain with me for life.

This is not the place to go into great detail, but I have to explain what happens, in brief.

There are 3 main constituents of exhaust gas that have toxicity,

CO, Carbon monoxide.
NOx, Nitrogen oxides.
HC, Hydrocarbons.


They are all 'simple' molecularly.

Look now at the cat, dispersed throughout its substrate and this is used as a carrier for 3 Noble metals, they are Platinum, Palladium and Rhodium.

Over the entire surface there is about 4 Grams spread evenly.

They are called Noble because they are non-reactive and can resist chemical attack, but they are full of 'holes'!

It is these 'holes' that allow the Catalysis to occur.

When the cat is heated within the range of 300 to 800 deg.C the simple elements are 'drawn' to the 'holes' and they settle in them or 'poke' through them, the Noble metals then chop them into bits! How they do this is by the atoms within the Noble metals changing their Quantum state and the change in orbit crosses the 'hole' severing the ties (valences) of the simple elements. Some of these severed atoms 'dance' across the surface of the Noble metal and are re-combined with others that have 'hovered' over the Noble metal as if in the grip of an unseen hand moving in a rhythmic intricate dance of their own to form a different element! The re-combining looks like a type of fusion but is really just valence attraction and this releases sufficient energy to 'clean' the surface of the Noble metals ready for the next molecule. My descriptive powers are not up-to the job of conveying the beauty of this piece of magic, the atoms really do dance, meet, combine and fly off together, it is stunning!

Once outside the specified temperatures the effect starts to disappear, and if the Temperature gets above 1050deg.C the substrate 'swamps' the Noble metals by 'luxating' and the Noble metals slowly 'sink' into the substrate.

So, if I am in awe of this process why do I despise its inclusion in car technology?

Noble metals are rare, very rare, and to get the 4 grams of them we must excavate about 2000 M³ of hard mineral, crush it, use dreadful acids and alkalis to release them from the minerals grip and then get them across the Planet, this actually causes in environmental terms more than 5 times the amount pollution that the damn thing will save when fitted to a motor car! That's just getting it and carting it away!

Then you have to make the device, which adds a little more pollution!

Look, it was a great way of shifting the pollution problem away from where it all started; LA. They had a problem with photochemical smog, and Ralph Nader decided to smear America's problem right across the World by exporting the pollution to Africa, Russia anywhere that the Noble metals could be found!

It is an environmental catastrophe!

Soon it will be used in evidence against the Motorcar and their Drivers. The worst thing you can do is add insult to injury by removing the blasted things.

So much damage has been done to get them on your car; you have a 'moral' duty to do the best you can to minimise damage caused.

jasonw3579 07-18-03 11:56 PM

i was about to say that.... thanks for saving me the time! ;)

n4ji 07-19-03 12:30 AM

Yeah, all the cat does is speed up the process at which the exhaust breaks down (AP chemistry nerd!)

BLUE TII 07-19-03 12:52 AM

You are graced w/ a reply from a venerable forum veteran like Cosmo Donk and this is your reply?

usually ice is the first to reply to my threads and not even the modification master cake??? hmmm i guess my threads are lame

Check out his website listed in his sig. and RESPECT him, or better yet treat all forum members w/ respect!

And Icemark, do you understand the Ian Wilkshire quote you posted?

Read it a couple more times, he is saying that politcians force consumers to buy cars w/ emmisions to placate niave neophyte environmentalists who don't think of the miles of strip mining that go into each catylitic, to stimulate economy by producing ever more complicated cars and even clean up after the diesel overland transportation, public transportation and commercial factories that spew out emmissions (modern cars IMPROVE the quality of air in large urban areas- so, hmm, where is all that pollution comming from.

Did you take his tongue and cheek plea for you to leave the catylitic on your car as evidence to be used against industry, politicians and niave environmentalists incase anyone sues them on behalf of the environment and to clean up after commercial industries pollution as a serious request?


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