MaxBoost!
Advice for fellow TR owners from Tom Shea Racing
Home phone until 9 pm 952-892-5669
Cell phone anytime (612)-209-9090.
Email ttshea@charter.net
"TSR" Switch Fuel System, save money, drive on pump gas!
TSR MaxBoost #2
For those of you that race your T.R., here are some tips. Traction is HUGE! Spinnin ain't winnin!
Good fuel is good, Better fuel is better. The performance level will be limited by the ability of the fuel to be stable at high cylinder pressure and heat. This will be affected by the boost level and spark lead.
Detonation is the enemy. It will not only cause damage to your engine, but it will also cause the computer to pull back the timing and boost. This results in a serious power reduction.
Get a knock detector. It will help you monitor this condition. The unit is not really the actual detector, but a monitor of the existing hardware already in your car. These units go for around $100.00 and are available from aftermarket suppliers.
The condition of detonation is a serious concern. I have been told by some, who have just installed a knock detector, that they thought it was malfunctioning because it was going off more often than they thought it should. I am telling you right now, don't ignore that indication! The detectors that I have checked out after hearing this concern proved to be functioning correctly. This just goes to show you how much detonation is present on a regular basis. If you go merrily on your way, and ignore this, you will wish you hadn't!
T.R.s with increased performance should have, at the very minimum, the following items.
1) Knock
Detector.
2) 30
PSI. Boost Gauge.
3) Adjustable
Fuel Pressure Regulator.
4)
Liquid Dampened Fuel Rail Pressure Gauge.
5)
Adequate fuel delivery, starting with a fused and relayed "hot"
wire to the pump, also see additional information below**.
6)
Ability to adjust the boost level. This can be accomplished with ECM chips,
after market High performance chips are (in my opinion) expensive and unnecessary,
until you go to larger injectors. An alternative is to take the boost control
away from the chip by disconnecting the boost line to the stock
electronically controlled solenoid bleeder on the passenger side, valve cover.
This line can then, be connected to a manual bleeder valve. You can
use a threaded waste-gate rod and or an additional spring if necessary.
7)
Engine tie down strap; 8) If you use leaded fuel you will have to replace your
catalytic converter with an "Off Road" test pipe. This pipe can have
a dump
for relief of downstream backpressure. A dump will allow the turbo to make more
boost, so be careful to set the boost down prior to running it
open.
You can then set it up when you determine the level of increased boost. Keep in mind that boost can creep up during a run, check it at the top of the run.
You may have to limit the amount of boost at lower load and earlier in the run, in order to keep it safe at the "Big End". If you have boost creep, it can be addressed by increasing your waste gate capacity. Sometimes a simple porting can do it.
Boost. The boost level of your 86 or 87 T.R. should be determined by the fuel quality. The maximum level, even with racing fuel should not exceed 21 to 22 P.S.I. to be safe.
Those of you that are already there, with the above-mentioned basics, and are looking for more, there are logical progressions that should occur if you want to get the most bang for the buck. The proper sequence of upgrades will provide a positive gain from each. The downside of not going by this logical progression can be an expensive modification that may not bring much, if anything, for the effort. These cars are expensive toys, and there should be careful planning involved when progressing through your evolution.
This process will include lots of Q&A with others who have been there and done that.
"Bench Racing". Some say it's half the fun. Others live for it. We all enjoy it to some extent. Let's make the most of the greatest resource we have, our club. We have some of the best talent in the country right here.
**FUEL DELIVERY: Fuel Pump Hot Wired, and possibly a "Helper" or higher capacity fuel pump. The fuel pump's ability to supply adequate fuel in stock form is limited, and in most cases is not enough. There are tests that can be performed to determine the output of your current system.
The standard accepted formula for determining the capacity of the fuel supply is 1/2 pound in weight of fuel for every horsepower produced. This is referred to as ".5".
Some opinions favor a richer ratio. The richer ratio of .55, .6, .65 are safe starting points but will have the effects of limiting power output and fuel fouling of plugs and engine oil. Each of these ratios is progressively 10% richer in steps than the previous. It is OK to start out a little rich and then tune lean as you go. Don't think that a rich ratio is the way to go as a standard. The proper A/F ratio for your motor will probably be closer to .5, or just slightly richer.
The stock engine was rated at 245 net HP. This is approximately 360 gross HP. Use the gross HP figure. 360HP x .5 lb. = 180 lb. of fuel required to support output. Fuel weighs approximately 6 lb. a gallon. 180 lb. divided by 6 lb. = 30 gallons.
These figures are for 1 hour. Therefore the stock pump is required to deliver 30 gallons an hour to support the stock engine output. Increases in engine output from various modifications will require a corresponding increase in fuel supplied.
A simple test is to disconnect the return line at just above the right rear axle. This will allow a measurement of the actual flow at the set fuel rail pressure. Because this is downstream of the regulator, the flow is not at the high pressure of the rail.
Make sure to set the fuel rail pressure to the "Delta" pressure. This is the equalized pressure that your pump would have to supply fuel against. This is the initial setting of the rail pressure at idle with the vacuum line disconnected, plus the additional pressure of 1 P.S.I. of fuel pressure for every P.S.I. of boost. This is typically around 40 to 50 P.S.I. of fuel pressure at idle and 20 to 25 P.S.I. of boost. Therefore your setting should be 60 to 75 P.S.I. for this test.
Just jump the fuel pump test lead to the back of the alternator. Run the fuel pump with the engine off. Set the pressure with your adjustable fuel pressure regulator.
When you have done this, disconnect the return line at the above the rear axle location. Use a length of rubber low-pressure fuel line to convey the flow to a gallon container. Time how long it takes to fill the container.
30 gallons for 1 hour = 2 minutes for a stock car. Remember that this is the minimum amount of fuel delivery that you can get by with for a stock performance engine. Inadequate fuel supply will cause your engine to run leaner and hotter and contribute to detonation and worse. Proper fuel supply is essential for our cars. Take this matter seriously.
If you have questions or concerns, call MAX BOOST!
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