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Silly question... but what size tires does the truck have on it? With 33s I had similar results, failing the low speed and passing the high speed on a rebuilt carb and perfect tune up.
I slapped a set of used 4runner spare wheels and whatever matching size, roughly 29" (stock 60 size), tires the used tire shop in town had on and passed the low speed test and high speed test with flying colors.
View attachment 2872377
Everybody overlooks gearing when it comes to passing the roller test. With bigger than stock tires, the engine is under more load to maintain the 15mph, often meaning that your emmissions will skyrocket.
California makes you test at 15 and 25mph, but doesnt care what gearing or tires you have.
I see that you are in the bay area, you can have the old rollers if you want to come down to San Jose to pick them up. I moved out of California this summer so I dont need them anymore.
I'm here in So Cal and in the process of restoring my '87 FJ60 I'm looking at replacing the orig. Cat and downside exhaust pipe and orig. Muffler.
FYI...
Magnaflow CARB/FED approved direct replace Cat...Part # 3391894 (flanged) from their Website...$1445.
New downside exhaust pipe, Muffler, and Labor...~$650.
Total + Calif. Sales Tax... ~ $ 2252.
Ouch!!!
What guide do these techs use to know what the visual should look like on all these different cars?
jumping on the bandwagon. just failed CA today (barely) carb rebuilt two years ago and passed easily. CAT is (aftermarket) 4-6 years old. time for another CAT? I understand the aftermarkets do not last for more than about four years or so. any ideas?
View attachment 2883334
Great point. I am running 33s and my previous smog pass was on 31s I believe. So you ran 31s in the back and 33s in the front for the test? I may need to run the 31s. Thanks for the tip.Silly question... but what size tires does the truck have on it? With 33s I had similar results, failing the low speed and passing the high speed on a rebuilt carb and perfect tune up.
I slapped a set of used 4runner spare wheels and whatever matching size, roughly 29" (stock 60 size), tires the used tire shop in town had on and passed the low speed test and high speed test with flying colors.
View attachment 2872377
Everybody overlooks gearing when it comes to passing the roller test. With bigger than stock tires, the engine is under more load to maintain the 15mph, often meaning that your emmissions will skyrocket.
California makes you test at 15 and 25mph, but doesnt care what gearing or tires you have.
I see that you are in the bay area, you can have the old rollers if you want to come down to San Jose to pick them up. I moved out of California this summer so I dont need them anymore.
Yep. I ony did the mismatched sizes for the morning that I took it in for the smog test, and since they only test in 2wd I only bought 2 old rims and used tires. The smog tech probably thought it looked strange, but it definitely works.Great point. I am running 33s and my previous smog pass was on 31s I believe. So you ran 31s in the back and 33s in the front for the test? I may need to run the 31s. Thanks for the tip.
I am running 31s and still didn't make the cut. i am wondering if my engine simply wasn't hot enoughGreat point. I am running 33s and my previous smog pass was on 31s I believe. So you ran 31s in the back and 33s in the front for the test? I may need to run the 31s. Thanks for the tip.
At first I looked at this pic and thought, WTF? but realized in 2WD you can have the different sized tires and just run to the test then remove.
Great f'kin idea! I'm gonna try that next year!
Yup. Prices of new CATs have skyrocketed (up from ~ $350 a year ago due to all the CAT theft and precious metal shortages). But notice how non-smog States the prices are only slightly up? Keep voting for you-know-who if you're ok with this shizzle.
A Diagram or Schematic of the vehicle being tested pops up on the Tech's screen, with location of various required smog control pieces .
Maybe lean drop mix adjust and try some E85 gas and the smaller rear tires (see above) and retest. You're very close except for the low speed running rich.
yeah, fingers crossed. can you run E85 all the time instead of normal gas?E85 is 15% Ethanol. The closer you can get to running straight E85 the better. And if you can wait until the switch over to summer blend gasoline, that's even better, too.
Just fill up with straight gas after you pass (hopefully).
The temperature probe poking into the original cat is a safety feature, not an emissions requirement.
The thing that really heats up the cat (maybe to the point of too hot) is long duration fast idling on a really hot day with the car not moving at all. While driving, the airflow created by the movement of the vehicle will cool down the cat
yeah, fingers crossed. can you run E85 all the time instead of normal gas?
two years ago i had zero CO on my test so I hope it is just a mater of getting it hot before the test. I had to wait about 30 minutes this last time. should have idled. wish I could wait for summer gas but smog is due this month.
@Spike Strip I Installed the Autometer A:F gauge with Bosch O2 sensor and would love to chat about the numbers I'm seeing. I have to pass Denver emissions in March, so I want to make sure I'm using my data from the A:F to tune the carb correctly before rolling into the testing center. I'll have a freshly rebuilt head by then so hopefully that will help, but I want to do everything I can to get it done on the first shot. My cat (oh wait, I don't have a cat right now - but I will by test day) has never had a temperature sensor for controlling the AI system. I really need to find one of those. Maybe a generic would work but I don't know if it would be calibrated the same as an OEM one was.
For anybody looking to rebuild a carb that needs an extra for rebuilding off the truck (maybe because you daily drive your 60 like I do) I have one. PM me and we can work out a deal. I had Jim C do mine a little over a year ago and it's still good. Yes the Slow Cut valve leaks on this one. It leaked on my old one and it leaks on my rebuilt one too. No problem passing smog two years ago and no drivability issues.
@Spike Strip Thanks for the input! The A:F gauge is a digital stepper motor controlled needle. I can see the accelerator pump hit the exhaust stream in less than a second. That being said, when I adjust the carb I give it some time before adjusting again. When I sent my carb to Mr. Chenoweth I was clear on being fully smogged and he said he would rebuild accordingly. I'm finding that at part-throttle cruise, maybe 70% throttle, I run VERY lean - around 16 or 17:1. This is typically on the highway going up a slight incline that requires a good amount of throttle input but NOT going wide open. I'm wondering if my secondary jet needs to go bigger. Right now I idle at ~12.5, cruise under light load at ~14.5-15, cruise under heavy load around ~16.5 (as mentioned above), and WOT gets me to ~14.5. I'm certainly not a carb expert but I'm thinking both the heavy load cruise and WOT being as lean as they are both points to the secondary jet. I'm going to adjust idle leaner for a while this week and see what happens. Maybe it's the balance between the mixture screw and the idle speed (air leak) screw as well.
Also, I thought stoich was 14.7 ... did you typo that one? By the way, my emissions test is a full driving test on rollers - not just a two speed or idle test.
@Spike Strip I'm considering getting 5-year classic plates, that way I'm smog testing every 5 years instead of every 2. I'm even considering desmogging between tests if I do the 5-year deal. The only problem is Colorado limits you to 4000 miles per year with classic plates, under penalty of perjury (a felony). I really, really doubt the state is spending a single cent going after people with classic car plates ... but, on the outside chance they were to "come after" me there goes my job and ability to provide for my kids. Oops. So the jury's still out on that.
As far as altitude goes, the theory is that slightly leaner is better because there's not as much O2 in the same volume of air being pumped by the engine as at sea level? I thought the A:F sensor was an O2 sensor, so wouldn't that already be compensating for the difference? My worry about the lean condition is that I've had two people tell me now that running so lean can cause localized extremely hot temps that can damage pistons and valves ... but what do I know?
ok! ran her in hot with some premium gas and got the winning ticket. stoked. two more years of care free wheelin.Don't run the E85 - Not good for vehicles that aren't designed for it. Bad for Carburetors! Bad for rubber. Dilute as much as possible after testing.
You can pay your fees online and then wait for the test - NO penalty that way, but you will have expired tags for a couple months. They usually give a couple of months grace. Also, FYI - New law in Kalif as of 1/1/22 The SMOG station can issue you registration Tags ON THE SPOT.
Theoretical perfect stoichiometry for Air/Fuel is 14.7:1 (fixed) You'll find the analog meter you have is slow to react, taking about 30 sec or so for the needle to move as you adjust the carb, so you'll need to make small adjustments, wait, more adj, etc ...
For testing try to get the mix around 15:1 or so (slightly lean). When I add E85 for the test, it goes way lean, up around 17.
After testing, I richen mix to around 13.5 or so for best performance, but I'm at approx 700 ft above sea level. Since you're at high elevation, you're probably going to want to keep a lean-ish mix. It's going to require a bit of experimentation to find where it runs best, usually around 14.7:1 Also, you said you're running a Jim C. carburetor? He's probably tweaked the jetting for best performance, so again, it's gonna take a bit of fiddling to get the carb tuned (I believe Jim does this for performance at his shop) for smog test.