Emissions retest another failure

[GOLDCYLON]

Ok fellas WTF is going on


1st Failed test with a bad drivers side factory Cat and DRM chip

Standards are 1.00 for HC
12.00 for CO
2.50 for NOX

Results

HC: 1.51 Fail
CO 8.38 Pass
NOX 2.71 Fail

2nd test with Jeal headers with Magnaflow cats and DRM chip


HC: 2.34 Fail even worse now
CO 8.86 Pass
NOX 2.54 Fail


Is it because of DRMs chip and mods? I still have the factory prom. What does the group think? Help

[tomtom72]

These metallic substrate cats do not get hot enough, long enough to do the proper job. That is the rub with these low restriction hi-perf cats.

Ron Kreigh, uses alcohol and gets the car to 230* on the water temp and he passes.

I would try the stock PROM, just for the emission test. Get the water temp waaaaay up there so you know the cats are hot. Maybe even do a temp header wrap on the cats to hold the heat in?

I had asked Mr. Haibeck about having the cats coated also to keep the heat in them, but he said that he didn't think that was a good idea. S/S disperses heat too quickly, that's one of the reasons professional chief's do not like to cook with it.

:cheers:
Tom

p.s.: thanks for not being sore at me for posting the corvette recycling thing!:mrgreen:

[GOLDCYLON]

What kind of alcohol? Should I unplug the fans to get the water temp up a never see above 60% of band since I replaced the radiator.

[jonszr1]

i agree with putting the stk prom in and getting her hot just before you go there . another thing you might consider is doing the seafoam thru the brake booster line . i did this to my white car and couldnt believe the junk that came out of the exhaust. also i have heard that changing the oil just before going helps .wish i had more ideas but where i am at we only have to smog cars when we buy or sell them

[jonszr1]

also if its needed i could send you the extra set of stk manifolds and cats for you to pass. i would send them for free just to help out . just let me know if its a need .another idea is maybe we could cut off my cats from the manifolds and adapt them to your exhaust .

[tomtom72]

I never asked him, but I would figure it would have to be the same as the stuff they put in the gas, ethanol, right? or is it methanol? Chit I can't even remember what's on the friggin gas pump.

Maybe just throw in a big bottle of Techron fuel treatment?

Fans, hummmm that is a problem. My first thought would be to block off some of the air flow using a small piece of cardboard slipped up in front of the A/C condensor...like the over the road truckers use those leather covers on the front of the radiator grill? Turning off the fans plural maybe dicey, maybe unplug the secondary fan might be a way to get the temps up towards the last 1/4" of the gauge where it's supposed to be 230* + ???

Clean plugs w/tight gap 0.35", clean air filter, clean PCV's, stock PROM, and hot water...then try & sniff it to see how close ya get. If no good, I'd try the header wrap on the cats & collectors and some of the piping leaving the cats.

Sorry Daryl, I'm not much help....go ask Jeff, he will know! You do have the A.I.R. system connected, right? Not sure if it makes a difference.:dontknow:

[tomtom72]

Okay, taking a deep breath and thinking out loud.....the stock PROM's fueling is rich. I get that from Mr. Haibeck's web site, if I understand what I was reading....

His Hi-performance chip pulls fuel out, I thought, but for headers he puts more fuel back in....I think again if I get this stuff which is doubtful.

The bottom line is a ceramic grid cat gets waaaaay hotter than a s/s metallic web type cat. If the cats don't get hot, then they can't do their job. Also, the grid or honeycomb cat presents a longer route for the exhaust gas to take to get out, therefore it gets treated more. The s/s cats let the stuff out too fast, so it's dirty. The reaction relys on the temp of the catalyst, which is a function of how long the exhaust gas stays in the cat. A higher water temp may translate into richer fueling?, to prevent detonation?, the richer fueling may provide enough heat for the cats to work at idle??? I really think that it comes down to how much heat can be kept in the cats, JMHO after all this out loud thinking.:o

[GOLDCYLON]

AIR system is disconnected as I was told its only function was to preheat the cats for about 5 mins before start up which is why we all hear that pump motor noise before startup. Im putting the stock 91 PROM back in which I think might resolve the NOX issue but im not so sure on the HC as its more than 50% worse than the stock cat. Wrapping may be a solution as well as denatured alcohol according to Jeff. I really dont want to hang the old cats backinto the system as the only option you have is used cats. Thanks for the ideas guys keep them coming.

[GOLDCYLON]

i agree with putting the stk prom in and getting her hot just before you go there . another thing you might consider is doing the seafoam thru the brake booster line . i did this to my white car and couldnt believe the junk that came out of the exhaust. also i have heard that changing the oil just before going helps .wish i had more ideas but where i am at we only have to smog cars when we buy or sell them


I changed the oil this week as well.

[jonszr1]

i do think the stk prom might help. summit sells that heat wrap. for 50 bucks i think you could wrap them both .

[Jeffvette]

Just to add some more info.

New plugs
New coils
New plug wires
Cats are new

Theoretically, this car should have no issues passing emissions. A couple of things in talking to Darryl.

AZ still uses the IM240 testing, which Oregon had and recently got rid of. Having a stock ZR-1 pass on them was getting tougher as the car was never designed to pass that kind of test, and they have also been lowering the passing limits here.

Second, if you have a jack rabbit operating the car on the dyno, it will fail.

Darryl is going to try the stock PROM and see where we wind up and go from there.

[XfireZ51]

GC,

I doubt it's the DRM calibration. Tuners don't typically touch the Spark and Fuel maps in the area that involves part throttle cruise. I'll bet it's happening on decel.

[GOLDCYLON]

I really dont know at this point, Im trying to do the right thing with new cats and even a new o2 sensor. At this point im trying to determine a work around. Daryll

[GOLDCYLON]

You do have the A.I.R. system connected, right? Not sure if it makes a difference.:dontknow:


No I dont I was told the A.I.R. tubes was only there to preheat the cats upon startup does anybody know different for sure? Jeff Flint states thats the case, are there any other opinions?

I dont remember seeing a smog pump or an air pump on our cars beyond the electric air pump and the air dirverter valve on the drivers side right?

[jonszr1]

jeff is right they are only for startup and shouldnt effect the test if the car is allready warm

[GOLDCYLON]

Well heres my course of action for tomorrow... Put the stock chip back in. Drive the snot out of it for about ten miles at 3000rpm before the test to get the cats nice and hot. Pull over and put in a gallon of denatured alcohol to about 1/3 -1/4 tank of gas, keep it at 2000 rpm while its is the test lane and then test it! Sound about right? GC

[FU]

Also turn the A/C on during the above and while being tested.

Good Luck

[GOLDCYLON]

Ahhh to strain the car even further ok Frank thanks for that idea I will. And turn it off before entering the booth. I will try to take a video of this run through the booth. Jeffvette is intriqued I think he just like to see punishing compliance in action. A few guys on the Grand National forum say they do this all the time to stick it to the man that the car is sputtering, surging and complaining so much that it freaks out the compliance nazis when they pass. I guess RONK was onto something here. Thanks for the help folks as always.

BTW
I just enjoy running the snot out of it too, especially with the Jeals as it barks like big dog now. I cant imagine what your sounds like Frank with that big motor. lol ;)

[PhillipsLT5]

Collector Ins in AZ= no test req
or
After failing x times and x $ in receipts you can get a waiver
You must be close to that
or contact Marc

[1990 415]

the alcohol to use is methyl alcohol. when i bought my first ZR-1 from Frank Urbanati it had a Jeal 368 with no cats. i got that car to pass emissions with no cats on methyl alcohol. you have to basically get all the gasoline out of the tank and then put in a gallon of methyl alcohol for the emission test. once you pass the test fill her up with premium asap. the methyl alcohol is clean but the LT5 doesn't like it for too long. i was elated when i got the 368 to pass without any cats. good luck.

[XfireZ51]

Maybe put in a next step hotter plug.

[Sgreg]

Ok fellas WTF is going on


1st Failed test with a bad drivers side factory Cat and DRM chip

Standards are 1.00 for HC
12.00 for CO
2.50 for NOX

Results

HC: 1.51 Fail
CO 8.38 Pass
NOX 2.71 Fail

2nd test with Jeal headers with Magnaflow cats and DRM chip


HC: 2.34 Fail even worse now
CO 8.86 Pass
NOX 2.54 Fail


Is it because of DRMs chip and mods? I still have the factory prom. What does the group think? Help

D, I've got the same set-up. You cannot pass with a mod chip. Put the stock chip back in for the retest and you will pass with flying colors.

[Aurora40]

Okay, taking a deep breath and thinking out loud.....the stock PROM's fueling is rich. I get that from Mr. Haibeck's web site, if I understand what I was reading....
He's talking wide-open throttle though. No matter whos chip you have, closed loop part-throttle on an emissions test should be the same.

I have also wondered about these metallic cats and how well they work. I have to take the VA test soon, hopefully they work well enough, but I have my doubts.

I wonder if swapping bullet ceramic cats in for the test would help enough to be worth it?

[GOLDCYLON]

Ok update.... Went to see my friends house Fred (A forum member) heres what we looked at Fuel rail pressure about 42 Lbs Constant and holds after car shut off, Ruled out fuel pressure, surging and Injectors. Put in the stock 91 Prom. Pulled plugs on Driver side two a little loose but nice even burn on the set (Light brown). Pulled plugs passenger side two loose plugs hand tight and suspect oil fouled. Two completly oil fouled #2 and #6 exceedingly saturated, could not even see the electrode on the end of the NGK irdiums they had about 25K on them. Put in a fresh set on non Tappered flat ACs as they were all I could get my hands on. What would cause one side to oil foul before the other. Fred suspects two week cylinders or seals under camcover?

The car with the stock prom idles about 650-700 with Rippies Prom it idled about 850-900. Would the Prom and the plugs as stated be enough to hose the test? From my view it should help but would it be enough?

[flyin ryan]

He's talking wide-open throttle though. No matter whos chip you have, closed loop part-throttle on an emissions test should be the same.

Allowing the fans to come on later will help get the engine a little bit hotter, at least on the way to the test. A hot day wouldn't hurt the cause either.

[flyin ryan]

What would cause one side to oil foul before the other. Fred suspects two week cylinders or seals under camcover?

How many miles do you have on, could just be the valve seals being tired.

[GOLDCYLON]

How many miles do you have on, could just be the valve seals being tired.


102K Its my daily driver Ryan. Jeffvette suspects the PCVs are part of this problem but without a doubt the valve seals are tired as well. GC

[jonszr1]

i think jeff has hit on the problem , we too often dont pull the pvc valves and the rubber connector at the back of the motor and clean it out . i would definatly pull that and the valves and clean them just before you go . GOOD luck hope ya pass . i hate having that junk over my head :thumbsup:

[Nick]

GC, where are the cats mounted? On my '94, the Random Tech metallic substrate cats are mounted directly to the Jeal header collectors. I can't believe they don't get hot enough in that location. Also, I'm running a Haibeck chip. Car has passed emissions in WA better the last two times run than it did when stock. :dontknow:

[flyin ryan]

pull the pvc valves and the rubber connector at the back of the motor and clean it out . Could be, for sure. my thinking regarding valve seals were you said some plugs were good, some were o.k., some were bad...with PCV valve(s) my thought is it shouldn't be so hit & miss on the plugs :confused:

[GOLDCYLON]

Ok fellas WTF is going on


1st Failed test with a bad drivers side factory Cat and DRM chip

Standards are 1.00 for HC
12.00 for CO
2.50 for NOX

Results

HC: 1.51 Fail
CO 8.38 Pass
NOX 2.71 Fail

2nd test with Jeal headers with Magnaflow cats and DRM chip


HC: 2.34 Fail even worse now
CO 8.86 Pass
NOX 2.54 Fail


Is it because of DRMs chip and mods? I still have the factory prom. What does the group think? Help

3rd Test today. New Plugs, Stock Prom, Car Temp was at least 230 you could see the thermals in the shadows under my car. I also threw in a bottle of Heet (Alcohol) in the last 5 gallons of gas I had in the car


HC 1.30 FAIL But better
CO 6.71 Pass but was not an issue
NOX 4.30 FAIL but worse I suspect the additive


Im convinced these CATS wont make it through any IM147 test. So I using another option.

[jonszr1]

i think ryan is right about the pvc system in connection with the plugs .daryll do you have a couple of leaking spark plug tubes ,leaking oil , i had this on my white car and found that when i used the tapered plugs those plugs in the leaking cylinders were darker .they also seemed to, not be tight when i went back and cked them . i went to the standard gasketed plug and this stopped some what. till i just bit the bullet and fixed the problem . my thoughts were that oil got into the combustion chamber everytime i pulled the plugs making them darker . now with the problem fixed they all look the same .hope this in some small way helps .

[jonszr1]

3rd Test today. New Plugs, Stock Prom, Car Temp was at least 230 you could see the thermals in the shadows under my car. I also threw in a bottle of Heet (Alcohol) in the last 5 gallons of gas I had in the car


HC 1.30 FAIL But better
CO 6.71 Pass but was not an issue
NOX 4.30 FAIL but worse I suspect the additive


Im convinced these CATS wont make it through any IM147 test. So I using another option.darn i was hoping youd pass :mad:

[flyin ryan]

darn i was hoping youd pass :mad:Ya me too, wow? i must say i'm not expert at all in this area...we don't have that testing up here. do you have to pay every time you try/go for a test?

[GOLDCYLON]

Ya me too, wow? i must say i'm not expert at all in this area...we don't have that testing up here. do you have to pay every time you try/go for a test?


1st test $36.00
2nd re-test Free
3rd test $36.00

My advise to anyone else considering long tubes is to stay away from the metal substrate bullet cats and go with the bullet ceramic cats. I think they are too free flowing and will never meet a 1.00 HC standard. My factory cats when not damaged would pass without a problem. GC

[jonszr1]

good advise , guess i am thankfull that i dont have to test except if i sell the car .

[GOLDCYLON]

GC, where are the cats mounted? On my '94, the Random Tech metallic substrate cats are mounted directly to the Jeal header collectors. I can't believe they don't get hot enough in that location. Also, I'm running a Haibeck chip. Car has passed emissions in WA better the last two times run than it did when stock. :dontknow:


Nick, right behind the collectors, I know heat was not an issue this time as the car was about at 80% band about 230. I held the car at 2000 RPMs with the AC on like FU said. I could see the heat thermals in the shadow my car was casting on the ground. Every states different I just dont think they can meet the 1.00 HC standard or the 2.5 NOX standard. Its possible its just too much motor for the cats. If I was to do it again I would go the ceramic route. I would not reccomend these to anyone, Jeffvette swears these are 100% identical to the RTs but who really knows. Its a non issue now. But I am leaving the cats in place as its the right thing to do.

Thanks for all the ideas folks, at least you know these did not work for me so buy accordingly.


Side note: The DRM Proms is back in and the car is happy so I am happy. I have never seen a car POWER through two exceedlingly fouled plugs and 2 suspect plugs that were loose. Its a testiment to the engine. This car is a beast that likes to be beat on. Try this with the girly cars. This is why I believe when its tuned right, it will run very very well.

[-=Jeff=-]

1st test $36.00
2nd re-test Free
3rd test $36.00

My advise to anyone else considering long tubes is to stay away from the metal substrate bullet cats and go with the bullet ceramic cats. I think they are too free flowing and will never meet a 1.00 HC standard. My factory cats when not damaged would pass without a problem. GC

Damn that sucks.. even Crooked IL never charged for Emissions testing unless you did not want it to 'count' then it was $20

[flyin ryan]

Has anyone ever tried or thought to try tying in to the PCV lines with an external electric vacuum pump? could tie in to help out the PCV system or eliminate the PCV set-up all together & just run the vacuum pump directly to the engine, would be a closed system. i'm talking about, rig it up for the test, PASS, then take it off again. i dropped off an engine at the dyno i use this evening & i took an electric vacuum pump i own to use on this enigne. not sure what the customer wants to do for sure regarding elec. or mech. vac. pump, so for now i'll just use the one i have around strickly for dynoing & he can make up his mind later. when i was dropping everything off i started thinking about this problem being discussed on here the last couple days. as i've stated, emission stuff is not my deal at all, but i use vacuum pumps, electric & mechanical, on 70% of the engines i do. it makes more power when done right, proper rings, ring lands cut accordingly etc., but it also helps clean things up a lot. i've never been a fan of the PCV deal, i understand why they did, just don't like it...

[Nick]

GC, here are my results from January of 2008 (last time the car was tested). Car has:

Jeal headers
RT metallic substrate cats
Haibeck chip
Stock injectors (at that time)

http://i8.photobucket.com/albums/a1/skedadl/scan-2.jpg

The numbers don't seem to correspond to those you are posting, unless you remove the decimals from your numbers (or add them to mine). I do not think the metallic substrate cats are the problem with your car.

Best of luck!

[GOLDCYLON]

My test is on a dyno is yours Nick? I think your state uses just and idle and cruise test. Ours runs up and down under load in a 1-6 shift point program X2 for about 10 minutes. I also think our state expresses mathmatically 150 HC as 1.5 which is your states standard and mine is 100 HC or a 1.0 standard. I believe our standards are tougher in AZ. :dontknow:

Also im running magnaflows vs Random Techs, they look the same but maybe a little different also DRMs tune might be different from MHs

[Nick]

Yes, this test was run on a dyno. The "cruise" emissions are measured while in 4th gear.

[GOLDCYLON]

hmm then the standards are different plus our equipment is a little different

[Pete]

You guys still have emissions,that sucks.

No more emissions for OBD I cars in IL

I'm CAT free and loving it. :dancing

Pete

[GOLDCYLON]

Pete in AZ there are emissions requirements for cars from 1967 to present. Only 1966 and older and collector cars are exempt.

[jonszr1]

geez yours are tougher than ca. they dont start testing till 75 when cats were introduced

[rhipsher]

Well D. I guess its time for you to move back to Texas. Haha!:mrgreen: The last time I got my inspection sticker on the Z it passed emissions with flying colors and I was almost out the door when the inspector tried to honk my horn and it didn't work. And he says well I can pass it if your horns don't work! I said well they don't get used very much. So he tried it again and they worked luckily. It passed every god forsaken test with every piece of electronic equipment they had while having a wond stuck up its butt. But by god they were gonna fail it over the stupid horn not honking and I'd be out $39. What a racket.:cool:

[GOLDCYLON]

Yeah the guy I bought it from told me ;) how the Texas Ahem inspection stamps work.... If you have cash you pass......

[PhillipsLT5]

Sounds like Chicago
No Emission @ Firebird Fri nite, just test&tune
You comin?
I will be there At 6

[rkreigh]

VA lowered HC to 48 ain't no way.

the alchy doesn't work too well with a "closed loop" chip as the ECM compensates seeing a lean condition.

I'm going to try open loop, rich as hell pure alchy

I don't have secondaries which doesn't help either. graham told me that was one of the big reasons they went with that design was to get more velocity up under part throttle. I have another method, use your wallet. less hassle and there are many "helpful" folks that will take you that route

what I don't understand is changing the emissions laws to be tighter than the car was designed to pass in the first place. that's just wrong.:mad:

[Aurora40]

what I don't understand is changing the emissions laws to be tighter than the car was designed to pass in the first place. that's just wrong.:mad:
I'm with you! VA seems to get stricter every time I take my car in... The other kicker is that newer cars don't even need to do the sniffer test at all. And of course the biggest kicker is that the jerks in Richmond who pass these laws don't even have to abide by them, it only applies to Northern VA!

[GOLDCYLON]

I hear you Ron thats why I gave up and went another route. Its hard to stay in complaince when the standards are a moving target.

The new cars are a joke to test, all they do here is plug the car into the OBD II scan port. No code no issue right. Well I know those codes can be removed at the PROM level.

[jonszr1]

cant one apply for a varience in va .plea your case with the supporting data from when our cars were built . one would think that,even they would have to alter the figs to match when the cars were built . either that or file suit to get a historical designation . i know its a pain in the keister but would think they either have to do that or buy your car . moving the laws to obsolite cars should be a crime .

[Sgreg]

Ok update.... Went to see my friends house Fred (A forum member) heres what we looked at Fuel rail pressure about 42 Lbs Constant and holds after car shut off, Ruled out fuel pressure, surging and Injectors. Put in the stock 91 Prom. Pulled plugs on Driver side two a little loose but nice even burn on the set (Light brown). Pulled plugs passenger side two loose plugs hand tight and suspect oil fouled. Two completly oil fouled #2 and #6 exceedingly saturated, could not even see the electrode on the end of the NGK irdiums they had about 25K on them. Put in a fresh set on non Tappered flat ACs as they were all I could get my hands on. What would cause one side to oil foul before the other. Fred suspects two week cylinders or seals under camcover?

The car with the stock prom idles about 650-700 with Rippies Prom it idled about 850-900. Would the Prom and the plugs as stated be enough to hose the test? From my view it should help but would it be enough?

You betcha. Ram two new plugs in and the stock chip and go for it . ;)

[Sgreg]

3rd Test today. New Plugs, Stock Prom, Car Temp was at least 230 you could see the thermals in the shadows under my car. I also threw in a bottle of Heet (Alcohol) in the last 5 gallons of gas I had in the car


HC 1.30 FAIL But better
CO 6.71 Pass but was not an issue
NOX 4.30 FAIL but worse I suspect the additive


Im convinced these CATS wont make it through any IM147 test. So I using another option.

Hot is not the answer. In Texas they run fans into the engine compartment.

[Sgreg]

1st test $36.00
2nd re-test Free
3rd test $36.00

My advise to anyone else considering long tubes is to stay away from the metal substrate bullet cats and go with the bullet ceramic cats. I think they are too free flowing and will never meet a 1.00 HC standard. My factory cats when not damaged would pass without a problem. GC

D, it is not the cats.

[Sgreg]

Yeah the guy I bought it from told me ;) how the Texas Ahem inspection stamps work.... If you have cash you pass......

A little exaggerated I think about the Texas emissions test. The results are totally computer generated. They have to be passing it as an antique.

[npritchard777]

I had issues getting mine to pass here in CA. I did two things, went back to original Delco plugs (had Bosh in there when it failed) and I did a top end clean to get rid of the carbon build up. It passed just fine after.

-Nate

[flyin ryan]

I had issues getting mine to pass here in CA. I did two things, went back to original Delco plugs (had Bosh in there when it failed) and I did a top end clean to get rid of the carbon build up. It passed just fine after.

-NateFunny you say that, i've 'Always' found Bosch to be absolute junk in the engines i build. They can't be 'that' bad, but i've had no luck with then what-so-ever.

[jonszr1]

i agree with ryan on the bosch fusion plug .being a plug nut (i try them all)car ran like junk. put in some E-3s and the idle was smoother than its been in along time,.ive also done the seafoam clean and couldnt believe the junk that came out of the pipes .

[GOLDCYLON]

A little exaggerated I think about the Texas emissions test. The results are totally computer generated. They have to be passing it as an antique.

Our tests are computer generated as well and they also run fans. I am only relating what the seller in Houston told me when I bought the car. He told me he PAID for the tag and gave me a wink becuase I asked him about emissions. At that time the passenger side cat was bad and he let me know it. I agree its not just the cats I suspect timing and other issues.

[kirkstingray]

Time to find the right person at emissions and pay them off. not much else you can do. Sorry to here you are having such a hard way to go. My time is coming also, my right side cat is gone just like yours. Good Luck GC. Kirk

[rhipsher]

Well D. If the guy that sold you the Z was up front about the bad cat then I would suspect that is gonna play a part in causing it to fail emissions. Has your Z passed the emissions test before where you live? When my cats were going bad there was a funny smell and eventually they broke apart and chunks as big as golf balls were being spit out the exhaust. It was a revolting development. Luckily Corey had a pair of manifolds with cats off a low mile 90 Z he sold me for $500. Passes every time. P.S my cats failed at 65,000 miles.

[GOLDCYLON]

Well D. If the guy that sold you the Z was up front about the bad cat then I would suspect that is gonna play a part in causing it to fail emissions. Has your Z passed the emissions test before where you live? When my cats were going bad there was a funny smell and eventually they broke apart and chunks as big as golf balls were being spit out the exhaust. It was a revolting development. Luckily Corey had a pair of manifolds with cats off a low mile 90 Z he sold me for $500. Passes every time. P.S my cats failed at 65,000 miles.


I bought the car three years ago. I replaced the passenger side cat also three years ago in order to get it through emissions. Yes the car passed test 2 years ago. I was discussing what I was told when I bought the car. My issue started with the drivers side cat three weeks ago. I have since moved on to headers and the new cats. When mine went this time it looked like a softball bouncing around inside the manifold.

[jonszr1]

we need to start a lobby in dc outlawing cats as being dangerous to pedestrians , when they break .hence no problem passing the smog boys :mrgreen:

[93RubyZ]

As it's already been suggested, what about collector car insurance? I think I've heard there are some insurance companies that have no annual mileage limit, and others that you can select your own annual mileage limit (the higher you select the more expensive it is). This may end up being the easiest way out for you at this point.

[LGAFF]

My receipts show when my 90 would not pass they put racing fuel in it and it passed with flying colors.....

[tomtom72]

My receipts show when my 90 would not pass they put racing fuel in it and it passed with flying colors.....

I know that this is proly a stupid Q about the gas, but if the higher octane gave cleaner emissions then would it be worth checking the knock sensor?


I just got my copy of Corvette from the Inside and I just finished the chapter on emissions compliance vs performance. I know I should not think that I understand all of the theory. But the knock sensor does play an important role even in controlling emissions, or at least that's what I thought Mr. McLellen was explaining....:redface:

:cheers:

[xlr8nflorida]

Damn that sucks, sorry for the rat race.

I'm glad I don't have emissions. What a waste of time, meanwhile China is pumping tons of pollution into the air everyday.

[rhipsher]

I bought the car three years ago. I replaced the passenger side cat also three years ago in order to get it through emissions. Yes the car passed test 2 years ago. I was discussing what I was told when I bought the car. My issue started with the drivers side cat three weeks ago. I have since moved on to headers and the new cats. When mine went this time it looked like a softball bouncing around inside the manifold.
Man that would stress me out to not passing. And yes! When that ceramic honey comb breaks apart it sounds like a bag of rocks banging around in there. I'm getting ready to have Corey make me a set of ceramic coated Jeal headers. I hope I don't run into the same problem your having. Because the guy that does the inspection goes strickly by the book here and does not deviate. If I tried to bribe him he would probably turn me in.

[flyin ryan]

I know that this is proly a stupid Q about the gas, but if the higher octane gave cleaner emissions then would it be worth checking the knock sensor?


Has nothing to due with octane rating...race fuel is a pure/dedicated blend. doesn't have all the junk in it. When i take apart a street engine compared to a race-fuel engine, the race-fuel engine is wwaayyy cleaner compared to the street engine. guys will pop by & see this & say, wow that race engine is happy, i'll tell them it's not really any more 'happy' than the street engine just looks that way because the street engine's pump gas fuel is so full of garbage (additives) the fuel it self isn't allowed to do it's job were the race fuel can, race fuel only has 'one' job. i'm sure lots of you guys have walked by a car running race fuel & know the smell, well think about that compared to a pump gas vehicle, they smell brutal, makes a guy wanna puke. what your smelling is all the extra pollution emission crap in that pump gas fuel. i'm short on time but that's a quickie expanation.

[Jeffvette]

i'm sure lots of you guys have walked by a car running race fuel & know the smell.


That is the best smell in the world.

[xlr8nflorida]

That is the best smell in the world.

Don't you mean the 2nd best smell in the world?!

[Jeffvette]

Don't you mean the 2nd best smell in the world?!


Well, I've come across some skanks in my life. But race gas always has the sweet smell.

[Pete]

Real gearheads use C16 for aftershave.:)

Pete