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TR6 TR6 EGR valve

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Rob DeScherer

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Is there any problem with removing the egr valve from my '74 TR6? Most of the emission control stuff is already missing. What effect will this have, and are there any adjustments that I should make? Thanks for the help
 
Your emissions will increase. You can remove it, however I'm not sure if it's legal in your state.
 
The egr valve's job is to control combustion temperature. When the catalytic converter was added the temp had to go up. The converter does not become effective until it reaches 600F, and in order to maintain that temp, the engine temp had to rise. Thermostats were set in the 160F range, and increased to 190F. However, the increased temp/pressure caused pre-ignition (spark knock)which greatly increases hydrocarbon levels (unburned gasoline) and carbon monoxide (partially burned gasoline). To control this, the egr was added. What it does is pipe back a controlled amount of exhaust gas into the combustion chamber. Since the total capacity of the chamber is fixed, there must, by definition, now be less combustible gas in the chamber, and so therefore when the spark ignites, the burn is less. Typically an egr recirculates 20% gas back into the combustion chamber. So, if removed, you will experience pre-ignition unless you either retard timing which will cause hard cold starts and poor combustion, or change the thermostat to drop combustion temperature. If the catalyst is still on the car, it will no longer function if temperature is lowered.
 
The early TR6's had very little "pollution" paraphenalia on them. I think the intake was changed somewhere around 74 and stuff was added as time passed. My 73 has zero pollution on it, Louisiana has no emmissions checks. Mine is running at 8 degrees BFTDC and has no problems. The pressure in the valve cover is sucked via the triple ZS carbs into an oil recirculator which drops back into the pan (Goodparts). I see no problem modifying your pollution setup if you can get it to run better and pass inspection.
We drive these babies so little in the big scheme of things that I really don't think we are adding to global warming. My son is an environmentalist, catch-and-release vegan in Oregon and he loves to drive my little hotrod when he comes home for a visit.

Bill
 
[ QUOTE ]
We drive these babies so little in the big scheme of things that I really don't think we are adding to global warming...

[/ QUOTE ]

I guess that's true of all my cars.

Probably also true if I cheat on my taxes.

Littering by me also won't make much of a difference.

That 'big scheme' thing covers a whole lot of stuff.
 
Geo, and others...
The quixotic nature of my comments should not be interpreted as a lack of character. My TR6 is indeed modified for performance but not at all costs. Because I keep it in the best of tune and have had it checked for harmful emissions (even though Louisiana offers no such service), I know for a fact that I do not exceed the levels of emission that the car came with in 73. I hope not to be "misunderestimated"; I NEVER litter and ALWAYS pay my taxes.....
Methinks we are treading on dangerous ground here....

Bill
 
On a totally different subject, Dr. Bill, how is your J type OD doing? Is it repaired yet? I was wondering how long the vendor will take to return it to you.

Thanks!
 
Thanks for the help, guys. There is no catalytic converter on my car, and I am running a ss exhaust with twin pipes. I have installed a 160 degree thermostat. If I remove the egr valve, I guess I will just plug the hose. I don't have to worry about state emissions testing, as my car does not have to go through inspection because it is registered as an historic vehicle. Hopefully I am not harming the environment, as it is something that I care about a great deal.
 
Lets get right to the point, TR6s never had cat converters, the rest of the comments are political, and we don't want to go there
 
Mark,
He said he is switching it out and shipping this week. I hope.

Bill
 
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