What brand catalytic converter is best for testing?

[SuperTTA]

Hi,
I just barely passed emission testing here in Houston. The cat converter on my car is a Catco cat I bought from Summit racing last year.
I was wondering if a Carsound (Magnaflow) cat or Random technology converter would be a better choice to help me lower the HC's on my car.

Here are my results
25 MPH
HC Std =152, result 145 Pass
CO% Std=.97 result .46 Pass
Nox Std=1082, result 872 Pass
Dilution Std >6.0, 14.3 Pass

15 MPH
HC Std =157, result 157 Pass
CO% Std=.88 result .47 Pass
Nox Std=1184, result 859 Pass
Dilution Std >6.0, 14.2 Pass

This is on a stock TTA with 868 injectors, a TT emissions chip with fuel pressure at 42 psi. He recommends 38 to 40 psi, but my car ran like crap until I went to 42 psi. My block learn and integrator were excellent in the 124-128 range.
My coil pack/module have maybe 10K miles on them, the wires ohmed good(Magnacores), plugs were put in last year at emissions testing and I put a big 200 miles on my car this year.

Any recommendations for a CAT (2.5") that will help me lower the HC's?
Thanks in advance.
James

 

[gofstbuick]

Are you using a factory stock EGR valve and PCV valve?

 

[SuperTTA]

Hi,

I was using the stock AC PCV valve, but an aftermarket EGR valve. The EGR was on the car when I got it. The PCV valve is relatively new (less then 2K miles on it)
I burned a chip using the TTA image with the injector constant adjusted for my injectors the first test and failed NOX. Also the car was in drive for the first test.
The data you see is using the BBJK (GN emissions binary, with the same injector constant.) I looked at the EGR tables and the GN chip seemed to have EGR at all loads and rpms. The TTA chip had none down low.
The other difference is the 15 mph data was taken in first gear instead of second.


Will the EGR effect HC levels much? I thought they were more for NOX? I can find the AC delco EGR valve(I think it is part# 214-5346), is that equivalent to the stock one? I was looking for someone to buy a used stock one from last year, but no luck.
Any help is appreciated.
Thanks,
James

 

[gofstbuick]

Aftermarket EGR valves were never put through the rigors of a FTP test (federal test procedures), therefore the flow characteristics may not match the factory EGR valve. Too much flow from an aftermarket EGR valve could cause a HC problem, whereas too little flow will cause nox to rise. Get a Delco EGR valve and retest.

 

[SuperTTA]

Hi,
Do you have a source for the Delco EGR?
I have struck out at O'reilly's and XL parts. Discontinued.
Let me know.
James

 

[gofstbuick]

Even the GN EGR valve is still available from GM. Did you try your local GM dealer?

 

[Terry_H]

My EGR is Borg-Warner and it seems to get me by the smog nazi's.

 

[gofstbuick]

My EGR is Borg-Warner and it seems to get me by the smog nazi's.

Hey now, I resemble that remark :biggrin:

 

[Terry_H]

Hey now, I resemble that remark :biggrin:

.... and no offense intended to anyone, of course, especially admins!

 

[SuperTTA]

Hi,
I will try the dealer tomorrow.
Thanks,
James

 

[SuperTTA]

I have an update for you guys on the GM EGR valves. My local dealer did a search and found 3 in the country at dealers. I called a dealer in Illinois that was supposed to have one, but they already sold it.
I called another dealer in Florida that supposedly had 2, but they really only had one in stock.
I bought that one. It might be the last GM EGR valve seen by their system.

Delco discontinued them, so there will be no more produced.

Hopefully the borg warner is just as good for the future. According to Terry it works. Terry can you remember what level your car tested for Nox?
Later,
James

 

[Terry_H]

hmmmm.. it was a number of years ago and I can't remember what I had for breakfast this morning. ha!

I had failed NoX really bad, so bad I qualified as a gross polluter during a pre-test. I then installed the new EGR valve, but the problem ended up being the previous owner had epoxied the EGR port shut. I had to remove the intake to clean the port to get things working correctly. I also invested in a new turbo/downpipe around the same time and they furnished a smog chip. So there were a lot of variables sort of mixed together. The car originally came from Ohio, so I had to invest in a new charcoal cannister among other tidbits.

The car has passed CA emissions without issue that last 6 years. YMMV

 

[SuperTTA]

Hi all,
I received the new EGR valve today and it was in a AC delco box with the correct # on it. 17111570, #214-5346. Box didn't look as if it was ever opened.
But, the number stamped in the top of the valve is
17086016
139 91

Is that the number you see on the new ones? On the original ones?
Let me know in case I have to return it.
Thanks,
James

 

[tom h]

Hi all,
I received the new EGR valve today and it was in a AC delco box with the correct # on it. 17111570, #214-5346. Box didn't look as if it was ever opened.
But, the number stamped in the top of the valve is 17086016...

When I look up the 86-87 TR's EGR on http://www.acdelco.com, it comes up with

Delco 214-5346 (like you said),
GM # 17086016.​

Also, both 17111570 and 17086016 cross-ref back to Delco 214-5346.

Finally, a "vehicle list" for Delco 214-5346, http://198.208.187.182/internet/VehiclePartFits.jsp?autosel=A&part=214-5346 , shows this EGR is exclusively used on the Turbo 3.8L engines.

It seems the new 17086016 has superceded the original 17111570. GM does do that periodically, usually the new # is a legitimate replacement.

 

[tom h]

James, I see you drive a 1989 TTA, not a TR (oops!). The part#s and cross refs also refer to the TTA (not surprisingly). So everything I wrote above, shoudl still be accurate (caveat: I don't know the TTA cars very well).

 

[SuperTTA]

Tom,
Thanks for the response. That helps.
I also looked it up on rockauto.com, but I feel better coming from AC Delco.
I wish they would continue making it for us.
Later,
James

 

[JSAautomotive]

I don't think any one brand of cat is better than the other. But as a smog tech myself, what I've seen to be the case is........

The cat companies rate their cats based on the liters in size your motor is. They basically have 3 different sizes. My experience has been that the cat they recommend usually does not have the cross sectional area that matches the factory cats. So I guess what I'm saying is the factory cats seem to get the best ok. But as far as aftermarket goes, we always install the largest cats with the most cross sectional area of substrate possible. The cost isn't that much different, but the emissions make a HUGE difference.