Catalytic converter's! Do you have them installed, what kind, photos....

[Trevor Y]

I will be putting Cats on my 1972 Kuda with 383 auto.
I was wondering if you folks that have done this would tell me your story, what you purchased and maybe some photos.
Thanks so much
Please understand that I have to do this because of my sensitive nose.
I am running supercharged Acura NSX with high flow cats and that is what I need on my Kuda.
Thanks
Trev

[brads70]

I had magnaflow stainless cats on my 86 big block 455 buick . They lasted about 30 minutes before they melted the guts in them and I had to take them apart and remove what remained so it didn't block the exhaust flow. It was a pretty stout engine, no were near stock.
Hope that helps?
But really I'd suggest a wide band air fuel ratio gauge and tune the carb and getting running right. Cats throw off quite a bit of heat ( they need heat to work right) and our cars were not designed with heat shields.

[Cooter]

Sorry, but unless you wanna be buying those things every 200 miles or so, you better rethink Cats on a Carb'd engine, or even aftermarket Fuel injected set ups. Cats DO NOT CLEAN UP A RICH ENGINE. This will burn up a cat. This is why you CAN NOT run LEADED Racing fuel in a car with cats. The lead attacks the cat and clogs it up the same as a rich running engine. Bad idea. If the "Kuda" has a foul smell, tune it, or stick with the Acura.

[Jesus H Chrysler]

  A cat won't help your sensitive nose.  I'm assuming you don't like the smell of a rich engine.  I second Brad's suggestion and get a wideband O2 sensor and have the carb tuned properly.  If that doesn't fix the problem you may want to de-cam the engine so it runs a little smoother and cleaner.  I know that's counter intuitive to a muscle car but so are cats.  I had to put cats on my old Ramcharger back in the dark days of tailpipe sniffers.  They lasted less than a year and had to be replaced again.  My Ramcharger only had a 360 out of a cop car with a moderate cam, nothing too wild.  Rich mixture will kill the cat, not the cat killing the mixture smell.

[Trevor Y]

Thanks for your input gentlemen!
I will get the carb tuned the best it can be here in Edmonton by a well know carb tuning guy.
It is a Holley 80670-2 Street Avenger Model 4150 with vacuum secondarys
670 cfm  - electric choke - ready to go out of the box.
I did advance the timing a little bit on Sunday to smooth this thing out .
I also attached my Snap on timing light with digital tach and brought the idle screws out about 1/2 turn each to raise the idle up.
I didn't have a vacuum gauge so I used the highest rpm method instead of the highest vacuum method
That took a low end bog out of the system that was there before.
This last sunday was my second drive in the car since I got it.
Its this nice help and suggestions from you guys that will make this new purchase a joy and not a headache.
Regards
Trev

[brads70]

 With a carb that small, I'd say you should have no problem tuning it so it runs leaner. Maybe hotter plugs
( higher heat range) might help too. Have you pulled them and inspected them after a full throttle run? I'd suggest a MSD 6AL as well. I've found they really help in running cleaner. Start with the basics first , new plugs wires cap and rotor if they look questionable? I'm not sure that torker intake is helping things out either? Not really a low RPM/cruising type intake?

[MEK-Dangerfield]

That carb is small for a big-block.

I'm afraid the stinky gas smell is part of the hobby. The good news is when you get it on the hiway, you won't smell anything.   

[Trevor Y]

Thanks guys!
I talked to a great guy at Holley who owns a 68 GTX all matching and all correct down to the last hose.
He said to check my vacuum at idle in drive with the ole auto.
He said the Holley is set up for 13" with a 6.5 valve in it on the primaries.
He said with a non stock cam, I might be pulling less vacuum and dumping fuel into the engine.
I'll check that out and see what I have.
I have to find a big tree to put the nose of the car up against to do it though....lol.

I did some research on the manifold and up against 7 or 9 others, this manifold was good way down low.
I think this is it,
http://www.moparmusclemagazine.com/techarticles/engine/mopp_0207_intake_manifold_engine_and_rpm_range_test/index.html
So, I'll work through it all and see what comes of it.
I do have the MSD-6 with MSD coil.
I'll check through the rest as well boyz.
Thanks
Trev

[Trevor Y]

I guess I posted the wrong link for the manifold test comparison.
The proper one is below for the 383.
Regardless of this, what manifold do you guys recommend I hunt for?
A stock one maybe?
Let me know
Trev
http://www.hotrod.com/techarticles/hrdp_0712_mopar_intake_manifold_comparo/viewall.html

[brads70]

I guess I posted the wrong link for the manifold test comparison.
The proper one is below for the 383.
Regardless of this, what manifold do you guys recommend I hunt for?
A stock one maybe?
Let me know
Trev
http://www.hotrod.com/techarticles/hrdp_0712_mopar_intake_manifold_comparo/viewall.html

Hummm interesting, by that write up looks like the Torker works pretty good.

[Cooter]

THAT'S the intake comparison i was referring to in another thread. The tunnel ram on a 440 was king-o-the hill.


Most torque AND HP. I couldn't believe it. Ran really well. Nothing in the world wrong with a Torker. they work.

[msbaugh]

Smelly gas and burning eye balls! Part of owning a muscle car 

[HP2]

I've got that article plotted out in a whole bunch of xcel graphs. The results are very interesting as some popular combos actually suck in comparison to some not so well know set ups. Yeah, the tunnel ram really disproved a lot of theory in that test.

I wouldn't worry about the test being on a 383 and you running a 440. The configurations are similar enough the data is still reasonably accurate. Your absolute numbers may change, but the percentage of change between combos would be similar.

[Trevor Y]

Thanks guys, the car is running much cleaner with the replaced MSD-6A digital replacing the 2009 unit.
Also new fuel pump, mag pickup in the mopar dist, coil and so on.
going to the carb guy tonight hopefully for full tune if it don't rain.
I am happier.
Thanks
Trev