I just got my G-Tech Pro the other day.

I was out playing with it last night and I got to 60 in 7.05 seconds. The car is supposed to get there in 6.5 seconds but of course it was 80 degrees too. I can definately tell I'm losing most of that time in the launch. The engine tends to bog down if you don't get it just right. Once I find a nice straight backroad and practice the launches a little more I'll try it again.

 

make sure the traction control is off. at what rpm are you dropping the clutch? road and track determined 4200 rpm to be the ideal launch for their 6.4s times. for comparison, their test conditions were 93F and 30%RH.

 

With my auto-stick, I hold the brake and bring the Rs up to about 2,400 (traction control off).... The rear tires try to break loose then off the brake and mat the throttle. You need to do it in both directions on the same place in the road and avaerage it. My average G-Tech time is 5.6 seconds 0 - 60. But that's chipped w/ K&N and I also had 104 Octane Plus in 93 Octane fuel.

 

Oi... so little point to higher octane. higher octane does not add power! It makes it more difficult for the engine to detonate the fuel in the chamber, that's what it does.

 

?????

maybe not jet fuel in a standard engine... but the difference between 83 -> 94 is a huge difference in HP boost...

 

Somewhat correct -

Higher octane fuel takes longer to burn, which means the car can lean out and advance timing to gain more power. The ECU will do this to some extent. Which is also why you can run lower octane fuel in the car, but it will run rich and less efficent. Along with having less power.

The ecu has fuel maps and can sense how fast or slow the fuel is burning. It is mainly controlled off of the o2 sensors located closer to the motor. The 2nd further back is for emissions.

Now if you had an AFC and a data logger (software / cable for obdII port) you could lean it out a lot more on race fuel, which would also bump up timing. Not sure how it would react on this car, but I was able to get my friends integra type r into the low 13's with this. I wonder if it will adapt to the slk / crossfire. I'm sure it would.

 

Alright, next time i'm out i'll bounce it off the rev limiter and dump the clutch... we'll see how that goes.

And yes I did turn the traction control off. :lol:

 

Get the rev's up, but do not just "dump" the clutch. Slip it just pending wheel spin. Dumping the clutch will just cause it to spin and you will go nowhere fast.

When I launch the bike on the track I get the rev's up past 10k (on the 600cc) and slip the clutch. If I just dumped the clutch, the bike would be dumping me off next.

 

Hi DFWSBR,

thanks for clarifying the octane myth... I always laugh at the ricers that show up at my local GA airport and pay $3.15 for a couple of gallons of 100LL Avgas.
Since the ECU is not "expecting" 100LL or higher the map would indeed not be factory prepared for such a fuel so the money is basically wasted. If you go in like you did with your friends Acura and re-map this is a different story. But that would probably also affect the normal running conditions unless the aiport pump is the only one you're going to get fuel from ;-)

 

James you have no clue what you are talking about. My car has been chipped and does very well with a little octane boost. You seem to have something to say on every topic whether you know what you're talking about or not. I bet you talk even when no one is around, just to hear your own voice.

If you don't know what you're talking about keep it to your self. You demonstrate your ignorance constantly. I still try very hard to ignore you, but this is another case where I just can't let your ignorance be passed off as knowledge! You don't seem like a bad guy. Just stick to things you actually know about.

 

Higher octane means the fuel is less volatile, which means that there is less of a chance of detonation. The only benefit higher octane provides is when you advance your timing, buy hotter spark plugs, and increase compression. This is because higher octane only provides the benefit of a flash point safety margin to prevent the valves from being blasted. There is no point in using a 100 octane fuel in a street car. It will only do harm if you use it regularly because it will coat the cylinder head and walls and the valves with deposites from the extra additives and detergents in the higher octane fuel. It will also clog up your catalytic converter, causing a decreased exhaust flow and increased back pressure. That will lower the horsepower and damage the exhaust manifold if you routinely use high octane fuel.

Plus it voids your warranty.

Stick to the 91-95, even if you've chipped the car. The chipping optimizes the car for that range of gasoline. The stock ECU provides retarded safety timings just in case someone puts in poor quality gasoline.

 

Fuel doesn't increase your compression is does increase combustion (ie, longer burn = more power)!!! Higher octane fuel has a slower burn... not less volatile. It produces better power by powering the piston longer instead of just making a big bang and giving the piston a quick shot energy. Learn your Physics before you come explaining to me how fuel works. I've been an engineer for 35 years. And have been playing with race/street cars longer than that.

BTW... I've told you this before but you must have a very short memory... 10.0:1 compression is not low!!! It's not 12.0:1 but 10.0:1 is a very nice streetable compression for a normally aspirated engine.

Now, go back to school and pay attention this time! "D

 

:roll: :sigh:

Typically 100 octane fuel is unleaded, would not have any detergents because it is not designed for "cleaner air". Avation fuel might be different but race fuel is pure.

I used to run 116 BP supplied from a race shop locally here in town. One thing you left out was turbo charged vehicles and sport bikes. I could run up to 28psi on 116 and gain over 60hp with some tuning. Typically I could only run an average of 19psi on pump gas 93 octane.

Now, I will say it again. The stock ecu will compensate a little bit for higher octane gas, however much higher than 93, say 100, will only cause it to lean rich as ther are no programmed fuel maps for it. Having an aftermarket chip or controller might have the maps you need or the ability to lean out where you need it.

As far as coating the walls of the motor, do you mean carbon from running rich? Maybe so, but I think you are confusing this slightly with leaded fuel when you refer to the exhaust system. The carbon could also clog a cat, but leaded fuel is worse.

I had 3" from the turbo back no cat. It wasn't an issue in my car. Leaded 116 fuel however would kill an o2 sensor fast. Especially integra o2's :lol: my friend learned that the hard way. I could get 15k out of an o2 sensor with 116 being the only fuel it ran on.

As far as voiding the warranty? I don't think I've ever seen a case of this. Not even with running lower than oem specified gas. Typicaly cars that are designed to run on 93 can and will operate on a lower grade of fuel. Just because the gas you are getting isn't always 93. Gas goes bad over time, especially when not used. The ecu will compensate for it, and in result you will have loss of power.

I have seen some cars throw codes on a cold startup using higher than suggested octane. The obdII system would detect it, have a slight missfire, and throw the check engine light on.

Simple solution, stick to Premium. Everything else you are just throwing your money away on, unless you have some way to compensate for it.

 

Where did I say higher octane increases compression? I said higher octane only benefits a car with either advanced timing, high compression, among other things (such as forced induction as Adam mentioned). These are the things that bring about a need for high octane.

High octane means it contains more detergents, generally speaking. Unless you find some real quality race fuel. These detergents and additives that increase the octane also cause an increase in exhaust vapors that the cat has to filter.

But high octane does not in and of itself add power. You have the cause and effect chain backwards.

 

One last time...... Higher octane DOES NOT mean more Detergents!!! I don't know where you got that idea, but it's totally wrong!!! The only high octane fuel that I know of that's loaded with additives is 115/145 avgas and those additive are mostly for anti-icing.

 

It does not necessarily mean that it contains more detergents, but that is the most common and the most cost effective for petrol plants.

 

Where's the Forum Administrator? It is topics like this that will kill a forum audience quickly. These need to be nipped in the bud before they go this far. There is something called forum etiquette which a few around here might want to start practicing!

 

Or we could just make a new category called James VS WMichaels and limit their posts to that area. :lol:

 

Very interesting conversation going on here. I would say one of the biggest misconceptions is that "premium" gas is a better fuel that makes more power when used, and I am sure it is why the petrolium companies package it that way. I wish I had a dollar for every time I heard some one say, "I only run the good stuff." The higher the octane rating the harder it is to detonate, period. High octane gas needs to be used to prevent pre-detonation or "ping." If you are running 93 octane premium in a honda civic chances are you are pissing your money away and potentially harming your engine. Race cars use high octane fuel because they need to, it keeps the engine from pre-detonating. Pre-detonation will burn plugs and pistons and put undue stress on rods, pistons, cranks and associated bearings. A high compression, normally aspirated engine or one with a turbo, blower or nitrous will require the use of high octane gas, however there is the law of diminishing returns. I have a 12 to 1 motor in my Duster drag car that requires(and these requirements vary not soley based on comp ratio but other things like domed or dished pistons,shape and size of combustion chamber, quench, aluminum or cast iron heads, ignition timing, cam grind etc.) generally around 100 octane, if I run 116 octane fuel, power will drop off because this fuel has a higher resistance to combustion. This higher resistance will keep it from making the big bang and detonating thoroughly, which will lead to fouled plugs and possibly washing down the cylinder walls with unburned gas, which leads to lubricating issues, which leads to wear issues and LESS POWER! Too much of anything is not good, and most people will not know what is the optimum octane for there application with out experimentation on a dyno with various octane level fuels. If you "chipped" your car or bumped the boost up etc.. you switched to the higher octane to save your engine, not to "reap the benefits" of a more powerful high octane fuel. if you want a more powerful fuel consider using alcohol or nitro-methane. :wink:

 

I dont know you from any other posts pageoneresults... but Wes is well respected around here and a veteran with the Crossfire... I think many of us stand by him when he makes comments and I doubt that he would post anything that he didnt know about...