stainless steel exhaust welding in RI?

[DanB]

Can't find anyone to weld in a stainless catalytic converter into the RX-7's all stainless/TIG-welded exhaust using SS wire.

Anybody know of a shop that will?

TIA...

[brucesallen]

Not in RI, but you should contact ex COM CEO Bill Miskoe.

[Mick]

Or DSG if you can't ind anyone in RI

[DanB]

Dunno why I forgot DSG does all kinds of welding, and not too too far away.
Thanks to Mick, Ryan C., and Pete McP for reminding me!

Here's hoping that HC comes down enough to pass RI emissions...

[breakaway500]

I'm surprised RI has emissions on a '94. Ma exempts everything older than '96. Is it an idle test?

[DanB]

It's actually a road profile test on a dyno. Goes up to a screaming 25mph... HC limit = 2.75 g/mile. RX-7 = 15.75 g/mile.

Any pointers on stuff I could do besides the cat? E85 has been suggested. Since for the profile the ECU would be closed loop on the O2 sensors, I don't see a tune helping...

CO was a smidge high as well, but close.

[breakaway500]

It's probably the old IM240 test.. 4 minutes on an acceleration/deceleration dyno/roller. Some Inspectors are better than others at doing the test with positive results.. ..$$ .
Make sure the cats get up to temp..if they are located too far back from the engine,they won't work efficiently.Most of the stuff you add to the tank doesn't really work,unless your cat is old and dirty.E85 will throw high HC's just like gasoline if the a/f is a bit on the rich side (where it usually needs to be to run crisp) Popping off a small vacuume line (after the throttle plate) helped some vehicles that were just over the limit to pass. Make sure you put it back on before you leave..

[dradernh]

Is Mass still doing dyno-based emissions testing?

[breakaway500]

^ Nope. Ma. went to the OBDII plug-in testing,which really isn't testing the emissions coming out the tailpipe... ...and they made 1995 and older cars/trucks exempt from the OBDII "emissions testing".(Safety inspections only)

[dradernh]

^ Nope. Ma. went to the OBDII plug-in testing,which really isn't testing the emissions coming out the tailpipe... ...and they made 1995 and older cars/trucks exempt from the OBDII "emissions testing".(Safety inspections only)

So are there lotsa dynos sitting around unused. And for sale cheap?

[breakaway500]

They are around..but useless as a performance dyno. (They can't be loaded) There was a bunch of them around FS a few years ago when they became obsolete..many shops had purchased them rather than leased,and got stuck owing thousands for something they didn't need.

[DanB]

It's probably the old IM240 test.. 4 minutes on an acceleration/deceleration dyno/roller. Some Inspectors are better than others at doing the test with positive results.. ..$$ .

I think they might be sympathetic to the cause, but given the amount that I failed by, plus the fact that you can smell the car, plus no cats, I think they'll be more willing to "help" with a catalytic converter installed.

Make sure the cats get up to temp..if they are located too far back from the engine,they won't work efficiently.

Unfortunately, that's where it's going. Single cat aft of the Y, closer to the diff than the engine.

Most of the stuff you add to the tank doesn't really work,unless your cat is old and dirty.E85 will throw high HC's just like gasoline if the a/f is a bit on the rich side (where it usually needs to be to run crisp)

But there's fewer C's in ethanol vs. gasoline (1 carbon for every 3 hydrogens in ethanol, closer to 1 for every 2 hydrogens in gasoline).

Popping off a small vacuume line (after the throttle plate) helped some vehicles that were just over the limit to pass. Make sure you put it back on before you leave..

But if it's running closed loop, won't it just add fuel for the additional air to achieve stoichiometric?

Thanks, and any other pointers to lower HC appreciated!

[breakaway500]

The ecu can only add so much,as the O2's are narrow band and limited in their influence on the a/f table.It's the same reason it can't deduct any more fuel to reach stoichiometric now. Pulling the vac line helps..however you are way over the limit...so,make it a BIG line...
The cat waaaay back there is gonna really hurt its ability to do much... Maybe run a tiny one..you don't care about HP during emissions testing..I do remember having "test" cats in the shop for some difficult to pass vehicles..
I had a friend who swore by adding acetone to his tank he was able to pass HC testing...and some websites attest to this: "Acetone can reduce hydrocarbon emissions up to 60 percent. In some older cars, the HC readings with acetone in a 1986 GMC went from 440 PPM to 195, as just one example. Though mileage gains taper off with too much acetone, hydrocarbon emissions are nevertheless greatly reduced. Pure acetone is an extremely clean burning fuel that burns in air with a pretty blue, smokeless flame."
You can read about it here... http://www.pureenergysystems.com/news/2 ... 9_Acetone/

[brucesallen]

I don't believe the claim that 2 oz. of acetone in 10 gallons can boost mileage 30%. In 2006 Mythbusters proved it a Myth.

Tom and Ray say "It's worse than useless — it's also harmful. Acetone is the primary ingredient in nail-polish remover. And while it will burn and is a high-octane material, it's also a very powerful solvent. So while it's in your fuel system, it'll be eagerly dissolving all of your rubber components...like gaskets and O-rings."

Snopes says it is false: http://www.snopes.com/autos/techno/acetone.asp

[breakaway500]

I don't know about mythbusters etc and all the mileage claims..but back in the days of actual emissions testing, it did work to reduce HCs substantially..as I saw work it before my very eyes. It is not that agressive a solvent when mixed with gasoline in such fractional diluted quantities.I would use it before putting E85 in my car...that stuff is Hell on fuel pumps,injectors and regulators,unless the vehicle is designed to run on it. (Flex fuel vehicles)