Skip to main content ↑ ↓
Topic: Where to put cats? (Read 1306 times) previous topic - next topic

Where to put cats?

I'm running Mac LT's (for an AOD Fox) on my Bird, with a catless Mac off road H pipe.  I came across a good deal on a pair of bullet-style cats like the one I attached a picture of.  Looking at my H pipe, I don't see any good place where a ler shop could weld the cats into the H-pipe.  Would it be a bad idea for the shop to weld the cats into my flowpipes?
William

Where to put cats?

Reply #1 –
I really dont see much of a problem with it. Idealy they should be close to the engine. Maybe somebody else can shed more light on this.
85 Tbird 5.0
78 F150 351w
13 F150 4x4 3.5 Ecoboost

Where to put cats?

Reply #2 –
The closer you can get the cats to the engine, the easier it will be to pass the start-up emissions test. They will still work in flowtubes, but it will take more time before they get up to temp and start working.  It all depends what emission tests OH runs.  In MI we don't have emission testing...
1988 Thunderbird
306 HO w/ A9P processor
AOD w/ Transgo Reprogrammer
Full Digital Dash w/ twin Cyberdyne A-pillar gauges 
245/50/16 Tires on Snowflakes
Engine swap - CA smog compliant

Where to put cats?

Reply #3 –
Quote from: 88BlueBird;246662
The closer you can get the cats to the engine, the easier it will be to pass the start-up emissions test. They will still work in flowtubes, but it will take more time before they get up to temp and start working.  It all depends what emission tests OH runs.  In MI we don't have emission testing...


We don't have emission tests here, but I'll bet we will before long.  Reading what you had to say about the efficacy of the cats being affected by their distance from the engine, makes me really hope the ler shop can fit them into my H somehow.
William

Where to put cats?

Reply #4 –
Up here in Summit County we dont have a startup test. All you do is pull in, they put a sniffer in the tailpipe and run it on the rollers at 25mph until they get a good enough reading and then they check the gas cap. If they add emissions down there I'm sure it will be the same as all the other counties.
85 Tbird 5.0
78 F150 351w
13 F150 4x4 3.5 Ecoboost

Where to put cats?

Reply #5 –
They should be able to cut out a section of the H-pipe and weld them in. It shouldn't be that hard for them.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Where to put cats?

Reply #6 –
Quote from: thunderjet302;246772
They should be able to cut out a section of the H-pipe and weld them in. It shouldn't be that hard for them.


That would be great.  Just what I was hoping to hear.  Thanks as always for the input guys.  :)
William