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TR2/3/3A running the car on reguilar gas instead of premium?
- Thread starter karls59tr
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In the uk we use the higher grade as there is no or little ethanol which is the stuff that absorbs water and rots the bottom of the tank and attacks some rubber components in fuel lines and pump seals.
You may not have that issue. The lower grade fuel is marked E10 for upto 10% ethanol.
You may not have that issue. The lower grade fuel is marked E10 for upto 10% ethanol.
charleyf
Luke Skywalker
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P
The higher octane fuel better protects your valves.
If you have added hardened valve seats to the head then the use of regular (87) gas is okay.
Charley
Also not a mechanic here.
The higher octane fuel better protects your valves.
If you have added hardened valve seats to the head then the use of regular (87) gas is okay.
Charley
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Karl - take a look:
us.etsracingfuels.com
ETS is saying higher octane produces no extra power, except in engine specifically designed for higher octane. (And UK definitions of "octane" levels is calculated very differently from US definitions.)
You’re thinking about Octane the wrong way: 5 myths about performance culture’s most misunderstood rating.
Octane is one of the most commonly discussed, highly marketed properties of performance fuels. Fuel manufacturers tout their high-octane products. Octane boosters promise added horsepower. And Hollywood promotes “high-octane” thrills for the next installment of their latest street racing...
us.etsracingfuels.com
ETS is saying higher octane produces no extra power, except in engine specifically designed for higher octane. (And UK definitions of "octane" levels is calculated very differently from US definitions.)
Karl - take a look:
You’re thinking about Octane the wrong way: 5 myths about performance culture’s most misunderstood rating.
Octane is one of the most commonly discussed, highly marketed properties of performance fuels. Fuel manufacturers tout their high-octane products. Octane boosters promise added horsepower. And Hollywood promotes “high-octane” thrills for the next installment of their latest street racing...
ETS is saying higher octane produces no extra power, except in engine specifically designed for higher octane. (And UK definitions of "octane" levels is calculated very differently from US definitions.)
charleyf
Luke Skywalker
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I run 2 TR4s and 1 TR3A. They all use regular (87). And they all have hardened valve seats. The TR4s each have 20000 to 40000 miles each.
Charley
If you are not experiencing pinging with regular, then you don’t need premium.
Running premium allows you to advance your timing, which will then increase performance.
Interestingly, going to a higher altitude has the same effect on pinging as going to a higher octane value.
If you are not experiencing pinging, then higher octane by itself (without an advance in timing) will not change performance.
Increasing your compression ratio will increase your performance, but will increase your need for higher octane to prevent pinging.
Bottom line:
Octane cures pinging.
Pinging kills engines.
Running premium allows you to advance your timing, which will then increase performance.
Interestingly, going to a higher altitude has the same effect on pinging as going to a higher octane value.
If you are not experiencing pinging, then higher octane by itself (without an advance in timing) will not change performance.
Increasing your compression ratio will increase your performance, but will increase your need for higher octane to prevent pinging.
Bottom line:
Octane cures pinging.
Pinging kills engines.
As far as valve protection goes, an increase in octane values has no effect one way or another on valve wear (other than the damage to all components caused by pinging). Lead was introduced many years ago to gasoline to prevent pinging damage to the then “modern” high compression engines. One claimed benefit of this added lead was increased protection of valves. The science of this is way above my pay grade, and still generates lots of discussions and confusion.
During the unleaded transition period, most refiners found other ways to boost octane without the use of lead (and now all have). Some though, like Union Oil, offered unleaded in low octane regular for new cars, and premium leaded for older ones. This confused the issue of what older cars truly needed, lead or high octane, which is really an apples and oranges discussion for most cars.
To further confuse the issue, the formula to compute octane values was changed at the same time, leading everyone to conclude that removing lead had resulted in only lower octane gas being available.
Confusing, heck yeah…which is why those of us with an old car addiction are still debating all this 50 years later!
During the unleaded transition period, most refiners found other ways to boost octane without the use of lead (and now all have). Some though, like Union Oil, offered unleaded in low octane regular for new cars, and premium leaded for older ones. This confused the issue of what older cars truly needed, lead or high octane, which is really an apples and oranges discussion for most cars.
To further confuse the issue, the formula to compute octane values was changed at the same time, leading everyone to conclude that removing lead had resulted in only lower octane gas being available.
Confusing, heck yeah…which is why those of us with an old car addiction are still debating all this 50 years later!
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TR - it is SO good to see the "octane" discussions again. Most young guys I know have no clue (1) how an engine works, and (2) what regular, midgrade, premium, supertest, etc. even mean these day. One of my favorites is "I always fill the tank with 1/2 regular and 1/2 premium, just to give my classic a treat.
oy.
All cars need oil, right?
Anyway, thanks for bringing this up.
TomM
oy.
All cars need oil, right?
Anyway, thanks for bringing this up.
TomM
charleyf
Luke Skywalker
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I got to thinking more about my answer. And it is incorrect. The hardened valve seats were needed when we switched from regular to unleaded gas.
Charley
Thanks for jumping back into the discussion Charley. I’ve been reading your posts on the various TR forums for several years now. I always considered you to be one of the smartest guys in the room, so was a little concerned when one of my posts appeared to contradict yours…thanks for clearing up the confusion. I’ve learned a lot from reading your many posts. I figure anyone that can keep these old cars happy through a Redding summer must know a thing or two (I’ve had the pleasure of talking to you and seeing your beautiful cars a few times at the Dixon show).
I’m constantly amazed at how much of what we would consider automotive common sense has been lost over the last few decades
charleyf
Luke Skywalker
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Tom,
I thank you for your post, which required me to think about this again.
I also thank you for the undeserved compliment. I am not the smartest guy. It is more like I have experienced more bone headed errors over the years and have learned from them.
Charley