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TR6 '74 TR6. Let's talk about disconnecting smog stuf

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Re: '74 TR6. Let's talk about disconnecting smog

This is how I see these add-ons to an otherwise very good engine. I am certain that many will not agree.

A PVC is a good thing. Before engines had a PVC valve they had a simple open vent sometimes with a hose hanging down to allow the engine to equalize pressure inside and outside mainly to keep the gaskets from being pushed out and leaking because of pressure building. The PVC valve simply draws the fumes into the intake manifold so they are burned in the cylinders and stops the reverse as when the engine might backfire.

If the EGR valve is such a great thing how come it is only on one cylinder? I have long felt the EGR is good at recycling exhaust gas with unburnt carbon particles. This would seem to lead to premature engine wear particularly the rings.

If the air pump is working all it does is inject air under the exhaust valves. It is supposed to add air to the exhaust so unburnt fuel can burn in the exhaust system. I wonder how such small tubes can make much difference considering the volume of exhaust gas that is produced. I am sure this and the EGR are only marginal efforts to insure meeting the then EPA standards.

The carbon canister and anti-run-on valve are only there to capture fumes from the fuel tank. The valve is only of value if it is used with the canister. I do not have them on my car. I have no discernible fuel oder and my car certainly runs fine.

If I was interested in concours I would have them all. As it is I only have the PVC valve and I am sure my car pollutes far less than the average politician.
 
Re: '74 TR6. Let's talk about disconnecting smog

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
No more inspections in CA....for now, anyway. [/QUOTE]

I've been reading about the woes of testing older vehicles under California's new standards in a Corvette forum. Apparently they are getting really strict regarding the evaporation canister/system. I guess the pressurize it with nitrogen(or something) and check for leaks. A guy was complaining he couldn't find anyone who would do the test on his car because they didn't want the liability of damaging his elderly system. Sounds like a real hassle. I'm so glad they did away with e-testing outside of the RTD-NFZ(no fun zone) here in Colorado!
 
Re: '74 TR6. Let's talk about disconnecting smog

I have a 71 TR6 and in NC you dont even have to get it inspected anymore, I also dont have any smog equipment so I really cant help you, but I would say take it all off and plug all the holes, besides a good engine in decent mechanical condition, you only need carburators, fuel and spark, distributor with vacuum or mechanical advance, dont need vacuum retard, for an engine to run, someone else with more experience can chime in.
 
Re: '74 TR6. Let's talk about disconnecting smog

frankenstang57 said:
A guy was complaining he couldn't find anyone who would do the test on his car because they didn't want the liability of damaging his elderly system.
Click to expand...
With respect, sounds bogus to me. The pressure used is very low (like 3 or 4 psi) and the system had to be designed to take the pressure originally (gas vapor can hit 15 psi or more). Saying a tester is afraid to test it is no different than them being afraid to run your car on the dyno for the tailpipe sniffer.

If either one fails during the test, "So sorry, you fail" and it's the owner's responsibility to fix the problem (or scrap the car).

BTW, the smog machine makes a noise very like an aquarium pump while doing the pressure test, so I'd guess that's exactly what it is. My Buick flunked last time, but all it needed was a new gas cap to fix it.

I don't like smog tests any better than the next guy (which is why all my Triumphs are too old to require them). But I do appreciate being able to breathe the air, and I've seen LA get a whole lot cleaner in the last 30 years. Kinda seems like a shame to be disabling smog controls that don't hurt anything and might actually help some things (like the evaporative stuff).
 
Re: '74 TR6. Let's talk about disconnecting smog

tomshobby said:
A PVC is a good thing.
Click to expand...
I agree (assuming you meant Positive Crankcase Ventilation instead of Poly Vinyl Chloride /bcforum/images/%%GRAEMLIN_URL%%/grin.gif ).

BUT, I don't feel Triumph ever got it quite right. To really have 'positive' ventilation, there must be a fresh air intake (which at least most of the Triumph systems don't have). And to really do it right, the intake must be clean, filtered air and a relatively large diameter. At sustained WOT operation, there is no intake manifold vacuum but blowby past the rings is at a maximum, so the large diameter intake allows backwards flow under those conditions (instead of building up pressure in the crankcase and causing leaks). Because of that, the intake also needs an oil vapor separator and provisions so it doesn't soak the main air filter with oil.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I have long felt the EGR is good at recycling exhaust gas with unburnt carbon particles. [/QUOTE]OTOH, if your engine is running so bad that it's putting out unburned carbon particles, maybe it should be off the road anyway !
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I wonder how such small tubes can make much difference considering the volume of exhaust gas that is produced.[/QUOTE]The issue is not the volume of exhaust gas, but how much there is left to be burned, which is hopefully no more than 1 or 2 percent. Remember this is wasted fuel going down the tailpipe, so we want to keep it low as possible.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] I am sure my car pollutes far less than the average politician[/QUOTE]No doubt it pollutes less than Mt St Helens too. But that's hardly reassuring :^)
 
Re: '74 TR6. Let's talk about disconnecting smog

1975 & older cars are exempt from emissions
testing (at least for the time being).

- Doug
 
Re: '74 TR6. Let's talk about disconnecting smog

<div class="ubbcode-block"><div class="ubbcode-header">Quote:] The pressure used is very low (like 3 or 4 psi) and the system had to be designed to take the pressure originally (gas vapor can hit 15 psi or more). [/QUOTE]

Eh... I realize that. Just regurgitating what I read elsewhere. You be the judge.

https://forums.corvetteforum.com/showthread.php?t=1904723

I'm just glad I don't have to deal with it.
 
Re: '74 TR6. Let's talk about disconnecting smog

frankenstang57 said:
Eh... I realize that. Just regurgitating what I read elsewhere. You be the judge.

https://forums.corvetteforum.com/showthread.php?t=1904723
Click to expand...
Ah ... reading between the lines, I think perhaps the technician was worried that crimping the lines might damage them, and perhaps on that year Vette it's difficult to disconnect and plug them. The owner notes later that the lines in question are already cracking. That seems more reasonable.

Unlike all this crying in one's beer instead of just fixing it. IMO 10 years is about the limit for soft smog lines, so might as well change them all and be done with it.
 
Re: '74 TR6. Let's talk about disconnecting smog

AngliaGT said:
1975 & older cars are exempt from emissions
testing (at least for the time being).
Click to expand...

Maybe where you are but not where I live. 1968 and newer must pass emissions tests here.

Bryan
 
Re: '74 TR6. Let's talk about disconnecting smog

Sorry - I meant that for California vehicles.

- Doug
 
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