Octane boost

[23109VC]

I will chime in on this one - based on my own PERSONAL experience with ALL these things...

I used to have a pretty well modified Volvo S60R. the boost was increased and the octane made a HUGE difference in power. driving it on 91 CA gas vs 100 octane wa slike a different car...HUGE HUGE power gains.

I experimented with adding toluene and xylene - got at home depot and some paint shops

I also tried the over the counter stuff

I finally found a gas station near my home that sold VP 100 unleaded race fuel. that is THE way to do it if you MUST increase octane.

the over the counter stuff is crap. the ones with MMT may help...marginally..but nothing like race fuel. period. NOS brand race octane booster was the one I tried and seemed to help a little..but it was more like a band aid..it helped a small ammount, but it wasn't as good as race gas. not even close.

on my S60R...a high boost turbo car - octane was a huge factor. it helped offset detonation and allowed the car to run more advanced timing and more boost. it also offset power loss from hot ambient temps... which really sucked the life out of that car...

i can say that mixing xylene or touenewas a big fat PITA. you spill it on yourself..your hands burn...it's a mess...i hated it. fining a gas station near your home that sells VP 100 unleaded is great...i bought a couple of 5 gallon gas cans, filled them up..and then blended them in with my fillups.i woudl run 3 gallons or so with a tank of 91 and hte blend charts showed that got me to about 93 octane..enough to really feel the difference but not enough to waste money on unnecessary octane increases..

skip the over the counter octane boosters. waste of time/ money.
skip the xylene/toluene - big PITA / mess
find 100octane race fuel..put some in your tank when you're on empty and drive around and see if you notice any gain.

if you are LUCKY, you will noT notice any difference, b/c once you get hooked on race gas...it's addictive. if your car really needs it...you will hate driving w/out it. on my old car, the S60R, it WAS A HUGE difference, and driving w/out it - sucked. sucked sucked. at $6/gallon for the race fuelkk it just added to the expense of running my car..which was jus tmore $$ to spend on the car...

anyway... i'd just suggest you skip it unless you have a majorly modified car and are going to a track where tenths of a second are important to you.

to just drive your boxstera nd have fun - i doubt you need it.

has anyone here tried race gas in a stock boxster and did it do anything you could feel?

[Lobo1186]

thanks for the info. I bet that S60R was a blast.

[stephen wilson]

Sorry, I have to say it, a turbo engine reference has exactly zero relevence to a normally aspirated Boxster engine. Actually, even comparing another N/A engine is irrelevent, each and every engine design has specific octane requirements.

(Damn it, I try and stay out of "heated" threads, I'll go back to lurking now!)

[eightsandaces]

Originally Posted by stephen wilson

Sorry, I have to say it, a turbo engine reference has exactly zero relevence to a normally aspirated Boxster engine. Actually, even comparing another N/A engine is irrelevent, each and every engine design has specific octane requirements.

(Damn it, I try and stay out of "heated" threads, I'll go back to lurking now!)

It was never supposed to be a heated thread, we all have Porsches and summer is coming why would any of us be in a foul mood? I will again say toluene shows up in places you would never expect it. Next huge dump, start reading the contents of the products in your bathroom, after all the issue of Excellence gets pretty old between pressings, reading the prell might be a nice switch and it doesn't give you the itch to buy performance crap.

[Lobo1186]

it is in many places but care is still needed. for an example I spilt some on my side (I say some but It was from around my waist down to my thigh) I was using it it clean powder coating off a comercial lawn mower frame. It was early so I didnt leave work I decided it was no big deal two hours later I could not bear the pain any longer (it hurt that bad) so I told my boss and left. turns out it had burned me down my side and I had a scar there for a good year or two because of it.

that said... its really not that big of a deal I was stupid and paid the price but as I said earlier just be smart and you will be fine.

[stephen wilson]

I agree, it shouldn't be heated, but it's one with strong opinions!

On Toulene/Xylene, Just because they don't immediately kill you, doesn't mean it's not a long term hazard ( Kidneys/liver ). I washed my hands with gasoline when I was young, and poured used oil around the shed to keep down weeds, now we know these things were bad! ( I'm making myself sould very old@! ) I broke out severly using Xylene with a respirator,gloves and chem. suite. ( A related life lesson, don't take a leak shortly after handling chemicals, it's not pretty! )

I guess I don't see the point, even if it gains a few H.P., unless you're racing competitively. But, I guess I don't have to! Each to their own.

Well, it's a beautiful Friday for a top-down drive , only 5 more hours!

Steve

[eightsandaces]

Originally Posted by stephen wilson

I agree, it shouldn't be heated, but it's one with strong opinions!

On Toulene/Xylene, Just because they don't immediately kill you, doesn't mean it's not a long term hazard ( Kidneys/liver ). I washed my hands with gasoline when I was young, and poured used oil around the shed to keep down weeds, now we know these things were bad! ( I'm making myself sould very old@! ) I broke out severly using Xylene with a respirator,gloves and chem. suite. ( A related life lesson, don't take a leak shortly after handling chemicals, it's not pretty! )

I guess I don't see the point, even if it gains a few H.P., unless you're racing competitively. But, I guess I don't have to! Each to their own.

Well, it's a beautiful Friday for a top-down drive , only 5 more hours!

Steve

It's toxic as hell, I'm in total agreement just pointing out that it shows up in consumer products if you look. As far as the danger.... I inhaled more asbestos from brake pad dust that most, we used air guns to blow it all over the shop what did we know? I've irradiated thousands of people including myself, just ask Mrs Roentgen or Madam Curie if that's a goodplan for longevity!

Something will kill us all, you want an egg or candybar? I say eat up...

[jcb986]

Go withe proven people...Sunoco. I used it in the 60's...then they had 260 and 280 and 280 plus, 100 Octane.

http://www.sunocoinc.com/site/Consumer/RaceFuels/UnleadedFuels/

[Daniel R]

Since we are on the fuel debate, is there any benefits to running leaded petrol? My understanding about the shift to unleaded is that lead additives are not compatible with catalytic converters. My car no longer has cats, so does this mean I can use leaded fuel?

In Australia 98 RON unleaded is readily available, and is all I use in the boxster. I'm just wondering if the lead would somehow help the motor apart from increasing octane. Maybe it lubricates better or something??

Your thoughts are much appreciated.

[eightsandaces]

I was always told leaded gas was bad for the catalytic converter, that's why they changed the nozzle at first too, so one couldn't make a mistake in the changeover years. The Fiat has a wide open 4" filler.

[Lil bastard]

Originally Posted by Daniel R

Since we are on the fuel debate, is there any benefits to running leaded petrol? My understanding about the shift to unleaded is that lead additives are not compatible with catalytic converters. My car no longer has cats, so does this mean I can use leaded fuel?

In Australia 98 RON unleaded is readily available, and is all I use in the boxster. I'm just wondering if the lead would somehow help the motor apart from increasing octane. Maybe it lubricates better or something??

Your thoughts are much appreciated.

The lead used in leaded gasolines was a form called tetra-ethyl Lead and was initially only used in Premium or High Octane gas, which commonly became known as Ethyl - some companies even marketed it under this name.

This additive raised the octane rating of the fuel inhibiting detonation and also helped lubricate and seal the valves whose seats were made of soft mild steel for better sealing. This is why valve adjustment on earlier cars was so frequent -= the valve would get pounded further and further into the seat - the lead acted similar to RTV on a gasket.

Because engines today are not designed to use it, and are machined to much closer tolerances using different materials (esp. the valve seats), and usually with a much lower CR, using leaded gas in today's engines would not likely yield the same benefits. Aside from damamging the cats (by coating the ceramic matrix with lead, thus reducing it's useful surface area to react with the exhaust), it would also make your O² sensor inoperable after only a few miles.

And, all of this is aside from the obvious environmental issues.

Cheers!

[stateofidleness]

I've been using THIS about every 3 fills and I notice a VERY nice difference in the way my car performs (and sounds smoother)

is this just as bad as the "octane boosters" or is this stuff safe to use?

[Daniel R]

Originally Posted by Lil bastard

The lead used in leaded gasolines was a form called tetra-ethyl Lead and was initially only used in Premium or High Octane gas, which commonly became known as Ethyl - some companies even marketed it under this name.

This additive raised the octane rating of the fuel inhibiting detonation and also helped lubricate and seal the valves whose seats were made of soft mild steel for better sealing. This is why valve adjustment on earlier cars was so frequent -= the valve would get pounded further and further into the seat - the lead acted similar to RTV on a gasket.

Because engines today are not designed to use it, and are machined to much closer tolerances using different materials (esp. the valve seats), and usually with a much lower CR, using leaded gas in today's engines would not likely yield the same benefits. Aside from damamging the cats (by coating the ceramic matrix with lead, thus reducing it's useful surface area to react with the exhaust), it would also make your O² sensor inoperable after only a few miles.

And, all of this is aside from the obvious environmental issues.

Cheers!

Thanks for the reply.

My question was more from an academic perspective, not that I am going to fill my car with leaded fuel just because I have removed the cats. I didn't even think about the O2 sensors though. So I was right that lead additives had other benefits, it is just that the modern motor renders these benefits useless. I'll stick with the 98 RON BP Ultimate. Thanks again.

Daniel