Racers often want to drain their pump gas and replace it with race gas beforehand. According to Steve Wells, the easiest way to do this is:
Steve credits Norm Schilling for this method. He has also connected a switch in the engine bay for turning the fuel pump
Never leave the car unattended while draining fuel.
Strictly speaking, DSMs do not require premium fuel. However, the car was designed to accept higher-octane gasoline for a reason.
Octane is not a measure of the amount of energy in gasoline - rather, it is a measure of how well the fuel resists preignition, also known as detonation or 'knock'. Detonation is very hard on the engine, and must be avoided. The DSM cars incorporate a knock sensor specifically for the purpose of detecting knock. Higher-octane gasoline resists knock better than lower octane gasoline.
During normal operation, the engine control unit (ECU) adjusts the engine timing as far forward as it will go. This provides maximum power, but also increases the possibility of knock. This is especially true for turbocharged or supercharged engines, such as the 2.0L turbo 4-cylinder found in the upper model DSMs. Note that the ECU hears knock all the time - the problem has to be persistent to generate a reaction from the computer.
If the ECU detects excessive, continuous knock via the knock sensor, the engine timing is retarded until the knock goes away. This results in a power loss, but saves the engine from damage. So, if you fill up with 87 octane gas, your ECU will be forced to retard the timing quite a bit, and you will not get the rated power from the engine. Not only that, but the ECU may also be forced to limit turbo boost levels to accommodate the lesser quality gasoline, which again means a significant power loss. And yes, the ECU does have the power to do that - see [["My boost is not strong enough. Is there a fix?]]".
Once you switch back to premium, the ECU will eventually advance the timing back to original levels - after a while.
For full details on this and the role of the boost control solenoid (BCS) refer to the September 22nd edition of The Diagnostic Port, byTechnomotive.
The true way to answer this question is as follows: analyze gasoline samples from all the prospective gas stations in your area for a period of three to twelve months, then pick the consistently best gas.
In other words, this is an imposible question to answer. Gasoline quality and formulation vary enormously over the continent. Leaving aside race gas (100+ octane) there is no real way of telling which gas is the 'best' in your specific area. Just pick a high-octane brand and stick to it unless you have a problem.
For those unsatisfied with this answer, read the Gasoline FAQ (alternate link here), and seek out information from other local DSMers. Don't ask the Digest - somebody in California isn't going to be able to help you if you live in New York.
DSMs will realize some performance benefits from ultra-high octane gasoline. The extra octane will allow the ECU to advance the engine timing more. Some people report significant gains with race gas, while others describe only minor improvement. The prohibitive cost of these fuels generally restrict their use to drag racing applications only.
Note that this applies only to true racing gasoline, and not pump gas plus octane boosters. For more information, read the very detailed Gasoline FAQ (alternate link here), and this essay on high-performance gasolines.
For those who can't afford "straight" race gas, try using the gasoline blending chart provided by Osborn's Auto. Be certain to read thearticle that accompanies it.
You can use leaded fuel, with the following caveats:
- leaded fuel will quickly destroy the catalytic converter.
- leaded fuel will damage and eventually destroy the oxygen sensor.
Leaded gasoline also leave white deposits on the O2 sensor and housing; some mechanics may recognize this as being from leaded gas, and deny your warranty for a new oxygen sensor.
Some people also believe that aviation gas is dirtier than normal pump gas. Opinion on this is divided, with some people saying it is and others saying it isn't. Max Burke reports that aviation gas has none of the detergents usually present in automotive gas. This could be called a 'purer' fuel, but since it can't clean the engine as well, the engine might get dirtier inside as a result.
The most popular AVgas is 100LL (100 octane low-lead mix), which nevertheless still contains at least as much, and possibly more, lead as normal leaded automotive gasoline. The "low-lead" rating is in comparison to other aviation fuels; this amount of lead WILL wreck the above mentioned auto components. One Digest member suggested adding the Alcor TCP additive to the avgas to help prevent lead buildup in the engine. Consistent use of leaded gas or AVgas will probably lead to significant clogging of spark plugs and oxygen sensors.
Except for the above details, it appears that for practical purposes AVgas can be considered the same as normal leaded automotive gasoline. According to the Gasoline FAQ (alternate link here), even 100LL has more octane than most auto gasolines, so you will get the same performance benefits as with unleaded race gas, as described above. Also, some people can get aviation gasoline much cheaper than typical race gas prices, making the prospect more attractive. For more information, read the very detailed Gasoline FAQ (alternate link here), and this essay on high-performance gasolines.
For those who can't afford "straight" race gas, try using the gasoline blending chart provided by Osborn's Auto. Be certain to read thearticle that accompanies it.
Many people use them. No concrete drawbacks or benefits have surfaced despite the heated debate that surrounds these products, making them appear similar to highly publicized 'magic products' (some of which are listed here). As with 'magic' products, virtually no experimental data is available to either confirm or deny the claims. For more information, read the very detailed Gasoline FAQ.
The only legitimate exception to the above paragraph may be gasoline additives that incorporate the tetraethyl lead additive, or TEL. TEL was the original 'lead' in leaded gasoline, and has since been banned from pump gas in North America. TEL was used because of its anti-knock properties, which have been well documented. TEL additives can still be purchased from Kemco Oil & Chemical; their effect on DSM engines is unknown, but presumeably TEL additives will have the same problems as leaded race gas.
Formulas for do-it-yourself octane boosters have been circulating various automotive lists for a while now, including the DSM list. Read all about them in this post from 1996 - there are some interesting 'facts' on commercially produced octane boosters as well. GS-Xtra claims original publication of the formulas, which are also listed on in the maintenance section of the Vintage Triumph Register home page and the Team.net Scions of Lucas (SOL) Technical section on fuel and octane boost formulae - they got it from Vettenet. Mario "Porsche Killer" has added his day-glo version of the homebrew formulae here, and there used to be a link in the (now amalgamated) F-Body organization page.
Although this information obviously gets around, there are no known records of anybody actually mixing and using their own octane boosters.
Don't bother - they are just more 'magic products'.
Don't believe me? Read what the FTC has to say on the subject.
Factory specifications call for DOT-3 fluid in DSMs. Many DSMers use Ford Heavy Duty brake fluid - it reportedly has a high temperature limit. Canadians will be happy to note that Canadian Tire sells this fluid as well, listed as "For Fords".
Brake fluids are rated according to DOT (Department of Transportation) ratings, which were established in 1972 to provide standardization. Note that DOT-3 and DOT-4 fluids are NOT compatible and may not be mixed in the same system. Silicone brake fluids are DOT-5. They are not recommended for use because they have strange temperature characteristics, and allow water to accumulate in the brake system.
All brake fluids are hydrophilic ('liking water') meaning they tend to absorb water. This decreases their effectiveness, and is a reason why brake performance decreases over time. Replacing the fluid with new, unopened fluid is the only remedy.
They should not be tight. They should have rotational play. (but not in and out).
When changing injectors, use new o-rings and lube with a little motor oil.
When bolting in the fuel rail, just snug is fine. Otherwise you you risk cracking the plastic spacers and breaking the fuel rail. It's only aluminum, so you need to be careful.
Here is Dacowgod's post from the DSMLink nitrous controls + meth injection thread from on DSMTuners
By far the best way to engage Methanol with ECMLink is to first upgrade to V3 Full if you do not have it...
1. Dial your car in WITHOUT methanol first. Get the tune right w/ Low boost.
2. Wire up your Methanol pump's relay to engage with the FPS or EGR solenoid wire. (Remember the ECU switches this wire to Ground so you will want to wire this to the ground side of the Relay)
3. I have found it is best to engage based on Load.. Engagement point will be determined by what kind of turbo you have how efficient your intercooler/fuel is, etc. You need to figure out at which Loadfactor you normally start seeing knock and engage it a few points earlier. Sometimes its a little simpler for people to do it by RPM but Full boost really depends on load, so RPM will change. Its also good to point out that LoadFactor tracks Boost pretty well.
4. I usually set MPH range from 5-315 ... This makes the Methanol not engage while on Launch control.
5. Make sure Knock is set from 0 - 20 ... You do not want this to EVER turn off because of too much knock.
6. I usually deactivate with clutch switch and Rev limit.... to try to prevent backfires.. State change limit of 100ms works fine.
Now that your Controls are configured you need to go do a pull... You will notice your AFR's are Much richer (if its working properly) than they were before.... This is where V3 full comes in... Go in to the AuxMaps tab and enable secondary fuel adjustments.
7. Enable Secondary Fuel Adjustments and subtract a % of global fuel to bring your AFR's back down to where they are supposed to be (remember you are adding fuel with meth, so this is basically telling the ECU about it) so it will still run your target AF/R ...Test and Repeat until you are running your expected AF/R
8. Dont forget to tick the box To tell it when to apply the Secondary Fuel Adjustment (i.e. When Custom FPS is active if you have Meth wired to the FPS)
That is it if you are engaging with ECMLink. But what if you are not engaging with ECMLink?
I've found it best for your Tunes sake to still inform the ECU that you are adding a secondary fuel source. So what you need to do here is wire up a relay to switch to ground when your Fuel pump turns on... Then wire that "switched ground" To your Idle Switch wire. You can then apply the secondary fuel adjustment for the Meth via IdleSw input... so your tune will still line up accordingly with Meth enabled and spraying.... Progressive controllers will cause a lean dip here though so you should watch the tune and maybe play with the delay a little bit as ramp rate is usually pretty quick with progressive controllers for it to matter much.
If you're still using DSMLink V2 for FPS control... Then you do not get the AuxMaps and Secondary Fuel Adjustment feature... You will be forced to lean it out manually by RPM with the sliders... which will work..I did it for a long time...but it will throw your AFRatioEst right out the window and can cause some odd issues because your engagement point will change based on load.
Short answer: Yes.
For more details on this, Magnus has created a great document 1Gina2G (PDF)
If that link does not work, we have archived the document 1Gina2G Archive (PDF)
If you are reading this, chances are you are either having a problem with your cooling system, or would like to make it more efficient. Below is a list, both 1G and 2G specific, that can help when making your decision and troubleshooting a failed cooling system. This FAQ focuses on stock-style cooling systems.
Your cooling system consists of 5 major components. They are your Radiator, Thermostat, Radiator Cap, Water Pump and Cooling Fans. We will discuss these in detail throughout this FAQ.
To sum it up, there are only 3 reasons why your cooling system will fail.
1: Lack of flow
Typically this is caused by a failed water pump, a stuck thermostat, a blocked or clogged radiator. A failed water pump will have the tell tale sign of coolant seeping out of the weep hole. You will typically notice a large pool ofcoolant below your timing belt cover area. Barring any broken hoses from your Oil Cooler, this is usually a sign of a failed water pump.
A stuck thermostat will reveal itself when your car is at operating temperature, your coolant is full, however your upper radiator hose is cold. Eventually the pressure inside the system will exceed the radiator cap's spring and you will start pushing coolant into your overflow. Change your thermostat.
A clogged radiator will reveal itself when all others fail. Usually, you can visually see debris in between the fins of your radiator. If there is enough of it, it will impede airflow past your radiator, and the efficiency of your radiator will not be sufficient enough to cool your engine. Flushing your radiator is as simple as removing it, pressure washing or hitting it with compressed air to blow the fins clean, then flushing the internals with water. Introducing aftermarket equipment in front of the radiator such as an FMIC or oil cooler without proper ducting will also impede airflow.
2: Lack of Coolant/Incorrect mixture
Typically this is due to a leak of some form. Find it and repair it. Your cooling system travels through a number of areas including your water pipe, turbo (if applicable), Oil cooler, water pump, throttle body, heater core and overflow container.
The ideal mixture is 50/50. That's 50% Coolant (Ethyl Glycol) and 50% distilled water. This mixture works for most driving habits under most conditions, however, most of us do not fall under this "Average" driving habit, and increase of water into your cooling system will allow it to perform better. Water does a fantastic job of removing heat, so the more of it you have, the better. Do not run straight water, your cooling system requires coolant to lubricate and increase the boil temperature of water. A great additive for your cooling system is a product called "Water Wetter", and is found at your local Canadian Tire, Autozone, Part Source, Napa etc.
3: Pressure.
As your cooling system heats up, the water in your system expands and your radiator cap keeps this expansion pressure in your system, raising the boil point of the water. As you drive your car, coolant will be pushed out into your overflow as the system creates pressure. Albeit a small amount, this amount returns to your cooling system once the car shuts off. As the engine cools, it creates a vacuum and barring all the funky Fluid and Thermo Dynamics, replenishes the cooling system by sucking it in back through the overflow via syphon.
There are mainly 2 reason why your coolant will not be sucked back into the system:
1. Radiator Cap: A poorly functioning radiator cap will allow for too much coolant to be pushed out and/or not enough seal to allow for the syphoning of coolant back into the system.
2. Overflow bottle/hoses: The overflow bottle should be below or at level with your theromostat housing, and a line inside the overflow bottle that goes down past the normal cold level for your coolant. Cracks or tears in the hose between the overflow bottle and thermostat housing will also impede a suction of coolant, and will pull in air.
Pressure can also come from the combustion chamber. A failed headgasket will either allow for coolant to enter the combustion chamber and be burned, or push air into the cooling system. Typically, the signs of a failed headgasket would be one or more of the following:
1. Foaming of coolant
2. Burning of coolant (White smoke)
3. Oil in Coolant/Coolant in Oil
4. Overheating condition within 10 or so minutes of driving
5. Overflow bottle filling up/overflowing at operating temperature
6. Coolant being pushed out of the rad cap under boost
7. Lack of return from overflow bottle to cooling system
8. Increase of pressure in cooling system/pushing coolant to overflow. (This can also be attributed to a failed radiator cap)
Lets discuss the 5 components, what they do, how they do it and how to maintain/increase their efficiency.
Radiator
Arguably the most important part of the system, the radiator is a heat transfer device and allows for flowing air through the fins to transfer heat from the engine to the air and dissipate. There are three things you need to remember about your radiator.
1. Airflow
2. Coolant flow
3. Airflow
In order for coolant to pass through your radiator, it must not be clogged. Ensuring your radiator is free from contaminants will ultimately keep it working as efficiently as possible. Your radiator hoses are also a must-maintain part of this important system. Cracked, worn, or soft radiator hoses are just a few heat cycles away from failing. I have personally seen a car cooling after a run down the track and the upper rad hose splitting open before my eyes!
Airflow is also THE key to a properly working radiator. We add FMIC's, Oil Coolers, Transmission Coolers, Power Steering coolers all in front of the engine cooler and then wonder why our coolant temperatures start to skyrocket. If you look at a stock DSM, you'll notice there are many plastic shrouds all around the radiator. These are there to direct air directly to the radiator, and not let it bleed off from around the car. When adding upgraded components to your car, it is crucial that you imitate these factory shrouds by building your own ductwork to direct air to the radiator. Without airflow, the radiator cannot do it's job. A great test for this is to turn on your fans with the hood closed and see if it will suck a piece of paper to your FMIC. If it can, chances are your airflow is pretty good.
Thermostat and Radiator Cap
These two critical parts of the cooling system can be the difference between overheating and overcooling. The thermostat keeps the pressure in the system, upping the boil point and keeping all that nice expensive coolant in the car.
Quote:
There are three seals in the rad cap. One on the outside that seals the water neck housing. Second seal is on the inside that is spring loaded and seals inside the water neck housing. This one maintains the pressure in the cooling system. Once pressure builds past 11 lbs with a stock rad cap from the coolant heating and expanding, its pushes past this seal into the over flow until pressure falls back below the rad cap specs.
How does it come back in when it cools ? There is a third seal or valve which works in the opposite direction. Its the round metal thing in the middle of the second seal. When coolant contracts, this valve opens and allows coolant from the overflow to flow back into the coolant system. Under pressure and expansion, this metal valve is sealed shut against the second seal. The cooling system constantly goes through this cycle of expansion and contraction which your driving, the rad cap needs to be functioning properly on order for it to do so.
A 16lb rad cap will cause all your lines to be a little more pressurized than a stock rad cap, but will increase boiling point. You'll notice your overflow coolant level fluctuate more with a 11 lb rad cap than a 16 lb rad cap. I like to keep my cooling system a little more "loose" with the stock rad cap.
-- Credits to Reza Mirza
The thermostat is what regulates your temperature, and oddly enough, the pressure in the system as well. Pressure is defined as a resistance to flow, and the thermostat creates just that. Without a thermostat, you will eventually overheat due to lack of pressure, so keep it in there. Your thermostat can fail both open and closed, and it's pretty easy to figure out what will happen in either circumstance. Installing too low of a temperature thermostat will cause an overcooling condition, which can be just as harmful as overheating. Your ECU depends on the engine getting to a certain temperature for normal operation, and if the car does not get to that temperature, the ECU will always think it's simply still warming up, keeping it in openloop mode. In openloop, the ECU depends on it's internal tables to tell how much fuel to introduce, and typically, this is a rich mixture. Also, the ECU depends on thecoolant temperature to begin learning fuel trims. This temperature is around 180 degrees for a 2G, and 190 for a 1G. Also, using a colder "racing" thermostat to try and combat an overheating problem is rarely the solution. A car that overheats will overheat no matter at what temperature the thermostat opens, it will just take longer for it to happen.
Water Pump
A variable displacement pump, the water pump's job is simple; Keep the coolant moving through the system. The water pump rides on a sealed bearing and is spun by the crankshaft via the alternator/water pump belt. The "weep hole" is a small hole at the top of the water pump and in a failed bearing/pump circumstance, coolant will drip out of this hole. Typically it is best to replace the water pump every time you do a timing belt job, as you need to remove the timing belt in order to do it. Ensuring a good seal between the pump and block as well as between the water pipe and pump will prevent you from having to do the job more than once. Take your time!!
Cooling Fans
Properly installed, shrouded and working cooling fans are critical to not overheating in stop and go traffic. A 1G has a thermoswitch at the bottom passenger side of the radiator that controls the fans on/off, whereas the 2G has an ECU controlled setup. Different combinations of setups can both do the job equally (2 pullers, 2 pushers or one of each). The OEM fans work great, and if you can keep them, do so, however most of our upgrades prohibit such an idea, so they came out with slim fans. In this scenario, bigger IS better. If you can cram a 14" slim fan in there, do it. The more airflow you can provide to your radiator, the better.
Hoses
Last but not least are all the coolant lines and hoses. As your car ages, so do the parts, and with the expansion/contraction of your coolant lines, the eventually will begin to deteriorate. Check your lines every so often to ensure there are no soft spots, cracks or tears as these are signs of impending failure. The smallest soft spot will eventually lead to a leak or split in the line.
Coolant Mixture
Lets take a look at the coolant mixture. What is the best mixture? Some will say 80/20 water/coolant, some say 70/30, some will say 50/50, but it's all in what works for you and your area/driving style. If you live in a hot area, a 75/25 mix might work, but colder areas require more coolant than water, so a 50/50 is best. Ensuring your coolant mixture is correct, and that the system is full at all times will ensure your car cools itself properly. Air is the enemy to your cooling system, and it ALWAYS comes from somewhere. Be it a cracked line, failed rad cap or improperly burped system, air will cause all sorts of heating/cooling conundrums that can drive a person mad. If everything above is in good working order, you will never get air in the system, period.
So, there you have it, a basic writeup about a typical DSM Cooling System configuration, how it works and where to start when that temperature gauge starts creeping up on you in 30*C weather in stop&go traffic. I hope this thread has been helpful for you.
Typically, the stock fuel rail on the 4G63T engine is designed to handle the fuel demands of the factory power output. In its original configuration, with stock fuel injectors and fuel pressure, the stock fuel rail can typically support horsepower levels in the range of 250 to 300 horsepower.
If you are planning to modify the engine and increase its power output significantly, it is generally recommended to upgrade the fuel system components, including the fuel rail, to ensure adequate fuel supply. Aftermarket fuel rails with larger internal diameters, improved flow characteristics, and higher fuel capacity are available for the 4G63T engine. These aftermarket options can better support increased horsepower levels, especially when combined with larger fuel injectors and a higher-capacity fuel pump.
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