TR2/3/3A running the car on reguilar gas instead of premium?

[karls59tr]

I've never done this and probably wont but how much of a loss in power is there to run on regular gas instead of 92 octane? It's costing about $100 CAD to fill the tank up here in Winnipeg! What negative effects besides power loss?

 

[NutmegCT]

Certainly no expert! But the higher octane fuel prevents knock/ping depending on cylinder compression. I don't think 92/87 makes a serious dent in power, as long as knock and detonation don't occur.

Just my two cents!

Tom M.

 

[Hamish Racing]

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.

 

[charleyf]

P

I've never done this and probably wont but how much of a loss in power is there to run on regular gas instead of 92 octane? It's costing about $100 CAD to fill the tank up here in Winnipeg! What negative effects besides power loss?

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

 

[NutmegCT]

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...

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.)

 

[karls59tr]

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...

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.)

 

[karls59tr]

Have you tried regular in the tank? Noticed any difference?

 

[NutmegCT]

I always used 87 (regular) in my TR3a and had no problems. Didn't even need to adjust timing from spec.

 

[charleyf]

Have you tried regular in the tank? Noticed any difference?

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

 

[CJD]

These engines have low compression, so there is little to no performance gain running higher octane. Hamish Racer may be an exception! I bet he is running considerably more compression ratio.

 

[TR Tom]

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.