ok so my friends and i were sitting around and bsing like a normal sunday night and we got talking about seals and what not. i asked them if there would be a difference in apex seal life if leaded gas was run in a vehicle from day one. reason being (imo) back in the days of non hardened valves lead was used as a lubricant to help prolong valve life . i was wondering if anyone has , in the past, ran rotary engine with just leaded fuel and now in the presant run w unleaded and seen a noticable difference in rebuild time and longevity.

 

I know that in our race car, we run leaded gas, AND premix oil. The reasoning for this is the lubrication value of the fuel. Our oil metering pump was removed due to it having leaked and blown one engine, so as a point of failure, it was eliminated and replaced with the fuel lubrication method.

The downside to leaded gas is that is stinks, it's environmentally unfriendly, expensive, and it's hard on stuff that would be on a street car like catalytic converter. However, on a race car where the exhaust is fairly straight through without things like that, it works great. At $12/gallon for us to run it, it's not very feasable for a car being driven daily.

 

What is the benefit of running leaded gas?

So far you have informed us taht you do in fact run it, and the drawbacks of running it... but not the benefits. Please inform.

Thank You.

 

Lead is a relatively easy/cheap way to bring octane rating way up as well.

If you look at fuel prices, to get the same octane rating its more expensive in an unleaded version.

 

12 bucks a gallon is hardly what I would consider cheap

 

In my post, I explained we use it for the advantage of additional lubrication for the seals.

Also, it is a cleaner, purer burning fuel (when you buy race fuel), without impurities. And yes, it does boost octane.

I wouldn't run it in a street car though. Too expensive.

 

I just talked to a guy from mazdatrix at the san jose grand prix, and he said NOT to run leaded gass because of the buildup occurs on spark plugs and rotor face/apex seals. He even said that he has seen "***** of lead" inside of engines disassembled after running leaded gas for a while.

 

I wouldn't run leaded in my race car (12A NA).
In fact the Mazda Le Man car ran 86 octane.

The lubrication value to seals is marginal since the organic lead complex 'lubrication' I believe was designed to cushion the impact and rotational friction loads on the valves. When you build a race motor (reciprocator) today one uses hardened surfaces, DLC and phosphor bronze guides instead.

Use low octane, high calorific value fuel, with a top quality 2-stroke mix.

Y

 

High octane is not good for an N/A car.

 

double post.. fail

 

thats one of the stupider things i've ever heard. every single engine benefits from running a higher octane fuel.

it is safer for the engine, allows more timing and therefore more power (some newer engines even advance the timing automatically if i higher octane fuel is used)

 

And that is a very ignorant thing to say.

An octane rating beyond what is required to safely run the engine is not required at all. If an NA engine can be run at MBT on 87 octane there is no advantage at all to running more octane in and of itself.