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2,329 Posts
Discussion Starter #1
Got a used MSD boost timing master #5462 at a good price.

MSD Boost timing masters pull 0-15 degrees timing, have a start point from 1-5psi and pull timing from 1-15psi at a controllable rate of any amount between 0-3 degrees per psi (so 0.5* or 1.2*...).
This all seems useless with a factory F2T ECU.

But the MSD Boost timing masters run simple board mounted pressure sensors and these can be change and mapped out.

The unit I got runs a 2bar map sensor part number MPX2200AP which is 0-200 Kpa (0-2bar, 0-29psi) absolute pressure sensor (reads below and above atmospheric pressure) unfortunately this sensor puts out a rarely used signal for a map sensor, most put out between 0-5vdc but this sensor puts out 0-40milliVolts (mV) which is 0.04 volts.
So the BTM only starts to operate at above 50% of the Sensors signal output. (can be set from 21.3333mV to 26.6666mV).
Because of the 0-40mV output signal there aren't many replacement options for this sensor, I didn't have to mount it to the board it could float in the box or sit outside and be wired to the board but the only option I found is part number MPX2200GP which is a 0-200 Kpa (0-2bar, 0-29psi) gauge pressure sensor (reads only above atmosphere pressure/boost), this moves the BTM set start point from 1-5 to 16-20psi, personally I only needed to pull timing above 21psi and beyond 30psi but because there is no boost lag I only need to set the degrees (between 0 and 3) to pull the total amount of timing I need above 30psi.

While I was swapping the map sensor to gauge I unsoldered the start point potentiometers wires from the board because I want to run the potentiometer in the dash and not from the box, also I plan to measure the resistance of the potentiometer and see if I can swap it for one that raises the start point otherwise I will just use a solenoid valve to cut off boost pressure to the BTM until I engage stage 3 boost/water meth injection .

For the T3 60trim I am running this will suit my needs but for anyone running a larger turbo flowing more air at less boost this would be perfect.

This 626 is also running an extra injector controller that once ranged bellow atmosphere to 21psi but now has control from 0-36psi boost pressure. It has full fuel control and timing control on a stock ecu with boost cut removal chip.

2,867 Posts
Mazda Carnage, I've noticed over the years you use all kind of different ways to manage your engine but I've never seen you use megasquirt or haltech or anyother engine management system. Why is that? wouldn't that be easier?

2,329 Posts
Discussion Starter #3
Mazda Carnage, I've noticed over the years you use all kind of different ways to manage your engine but I've never seen you use megasquirt or haltech or anyother engine management system. Why is that? wouldn't that be easier?
Lets just say my total engine/fuel management (3 255pumps, 3 adjustable FPR's, 2 MSD 6al's, 3 Extra injector controllers (SDS, Haltech, Split second), 4 bungs, 2 450cc injectors(rc), 2 650cc injectors (rc), the MSD BTM, 2 water meth kits, Gauge pressure sensors, potentiometers... has cost me a total of 1000$ Canadian (760$ US), How much is a good haltech standalone?

My only real reason for standalone is to increase redline RPM and to set up a 5th gear cruising air fuel ratio that goes above 3000rpm without going pig rich like the factory set-up, making highway driving costly. I often hit redline cut in 2nd spinning and 3rd, the car accelerates faster than it can be shifted.
Both these problems could be solved with A) a lager final drive gear in the transmission B) a Getrag 6speed transmission with the same gear ratio's, a larger final drive gear and a 6th gear.
The factory H-type transmission has taller gears than many other front wheel drives, The F2T has a much shorter rpm range. Add an H-Type transmission gear ratio To a civic type R style peak RPM 8000+rpm and red line speed in every gear would be insane.

How far will the F2T rev? I have a 626 lx auto I drove years ago (parts car now) one of the transmission cables was loose and everything was rust treated so I didn't like to touch it (can't stand working in grease), it wouldn't shift at times to above 7000rpm and would hit 7100rpm using the hold button and forgetting to release it. It was gutless at those rpms and you had to kick the gas pedal to get it to shift, also it would bog in the rain, after a year I had to change the intake rubber pipe and realized their was no air filter in the box, throttle body was full of muddy sand, and I'm sure it's ran through the engine for a year, there was a quarry on the way to my shop so the road was always covered in sand. Free complete porting and engine cleaning.

So the top end (head,cam, valves) can handle constant 7000rpm but what happens under much faster acceleration, is the head like the transmission? If an F2 auto head can cruise along at 7000rpm so can an F2T head but does the rate at which it reaches 7000rpm affect it.

The F2 doesn't breath well at 7000rpm but turbo size and turbine A/R will dictate rpm performance in high rpm.

The 626gt no budget car on a 60trim t3, 2600cc's of 94 octane and 400cc's of water meth, a chip, a bunch of heavy porting work, internal modified wasted gate... At 26psi outruns a buddy's bmw m3 with precision 6262 turbo, computer tune, water meth, upgrated exhaust and intercooler running 20 psi and 10.626 quarter miles with massive wheel spin at 131mph the 626 in 3rd 4th and 5th on a role was faster, I got it running consistently and safely just above 30psi after that. Until the wategate hose popped off.

The 626 was so fast that despite the much larger list of higher performance parts on the other cars and in my shop, this car is faster than I expected the non budget builds to ever be and I felt I had unrealistic expectations.
But pull out to pass and floor it 20 feet from a car at 55mph and hold the pedal in 4th you clear their front bumper at 110mph while your passenger screams like a bitch.

The new 626 will be 200 lbs lighter, I have made 0 power modifications, all suspension, brakes, lighting, engine control (less power), extra wire harness connection plugs and harnesses (easier install and servicing), air horn, some audio upgrades.
The only thing this car needs is fuel efficiency, for cruise this car ran a potentiometer, resistors, a diode and AA battery allows me to control the ecu voltage received from the narrow band O2 sensor (0-1v).
So i have dial control over A/F ratios to 3000rpm. I am planing on doing the same with the rpm signal to the ecu using a pwm pulse width modulator allowing me to pull 0-300 rpm from actual rpm above 3000rpm.

So all ecu's are just voltage or ohm inputs and outputs, you can run stand alone and program the outputs or piggy back and control the inputs and tune around the factory outputs.

For now learning, figuring out and manipulating factory signals, making plug and play harnesses and wiring is enough work and crap in my head.

Eventually I will spend a lot of time looking into standalone kits, the main thing to figure out is crank timing signal, I thought of running a sensor below the starter that picks up magnets on the flywheel but that would be the same horrible unreliable set up Subaru's run (sensors always fail) and I hate Subaru's.
I don't want to add a ring gear to the utility pulley (no offense) but it is also a crappy set-up more on FWD than RWD, even Mazda uses this type of RPM signal on their cars. With my 89 mx6 GT I have had so much snow packed in around the utility pulley it chaffed the alternator belt up and cracked the lower timing cover, I had chisel the compacted snow/ice out with a big bar and hammer, no little exposed sensor will survive that. I loath individual coils and will stick with the stock distributor and coil (never seen either fail on any F2 engine in 20 years). I also don't want to grind a tooth of, I can vary the distributor supply voltage to anything needed (which changes the output signal voltage) or change the sensors in the distributor or double the signal output if needed but good standalone should have the option to run cam or crank pulse.

I want to run the 89 MX6gt on standalone but here no standalone controlled car starts at -30* celcius, Heck with 20W50 oil and 80W90 Gear oil the cars barely start on factory management.
The Megasquirt shop guys give up trying to start them at -7degrees Celsius.

But if I can exceed the maximum power potential of the factory F2T pistons on 94octane and water/meth injection (or pure meth) and stock ecu and piggy back management than there is no reason for me to run standalone.
If I can't than it's time for standalone.
And any tuning and maps I work out will be shared with the few still modifying these cars.

2,329 Posts
Discussion Starter #5
What about dynoing your car I’m sure It would make some good numbers.

Have you ever dynoed any of your cars?

No I have never Dynoed any of my cars, I have never had a car to the point there was nothing left to do on it or to add to it.

The 1989 mx6 GT was close to complete, I was going to the garage to assemble a painted trailing axle with new trailing arms to put on the car before having the car painted and it being complete when it was hit.

And of course with the new body I had to make 101 changes, bigger turbo, water meth, upgraded suspension, larger intercooler......

I don't think the cars will make any good numbers, I doubt the 626gt produces much more than 350hp and 450 ft-lb torque. Which on paper would make the car pretty slow compared to many cars today.
And if I actually had the wheel torque and hpr numbers it would sort of suck, people would be so unimpressed they wouldn't want to race and those that race without asking would think I'm lying.
I would rather just tell them: -The total cost including the car is under 5000$ and much of it is built with leftover parts and discarded junk, why how much have you spent?

I really don't know if a dyno does a car justice, maybe when comparing weight and dyno chart curves with equal traction and gearing, on two cars racing from a stop a dyno chart can paint a proper picture
of the outcome, what a dyno chart curve, vehicle weight and gearing doesn't explain is some cars ability to accelerate on a role. The graph shows RPM and power, rpm can represent engine rpm or actual wheel rpm (vehicle speed), it is better to chart engine rpm when tuning and better to chart wheel rpm when gauging a cars acceleration. Dyno's are inaccurate in the fact different shops running the same or different model dyno's all yield different numbers based on the type or how they are up and calibrated.

The way to write a dynamometer graph that would have meaning and purpose would be:
.......0- 0.35- 0.57-1- 1.32-1.5- 1.78 - 2 - 2.30- 2.47- 2.75- 3.05- 3.67 Time in seconds
---- 60...65...70...75...80....85....90....95....100...105...110...115...120 (speed MPH) Gear 4TH
--1700,2084,2469,2853,3238,3623,4007,4392,4776,5161,5546,5930,6515, Engine rpm.

This chart would have 5 points of measurement:
Engine Torque in ft-lb
Engine power in WHP
*Elapsed time in seconds with 2 decimals
*Vehicle speed in MPH or KPH
Engine RPM

The joke here is that you can stare at the torque curve and numbers, the horsepower curve and numbers and the engine rpm points all day long, heck you can have vehicle weight, gear ratios and aerodynamic drag numbers and still know less than *speed in MPH and *elapsed time in seconds and vehicle weight will tell you about how fast a car accelerates. Kinda funny isn't it because you can get acceleration speeds to time charts on the road while driving for free or at the quarter mile track using time from 1/8th to 1/4mile and speed from 1/8th to 1/4mile for 20$.
Dyno pulls around here are 150$.

Maybe some day I will have an extra 150$

99% of the time dynos are used to tune or validate aftermarket parts performance gains.
Personally I have a very strong sense of intuition when it comes to cars (and everything else) and I learned to use it, after intuition comes conscious reasoning. Intuition is impartial, conscious reasoning is not. Your (You represents anyone well anyone with a clue) driving and feel something is wrong with your car, you're brain knows but hasn't told you yet, you think through what doesn't feel right about the car and evaluate why, wishful optimism often leads to dismissing intuition but like in life if you think something is wrong it usually is, it could just be a small amount of fuel burning in the exhaust that you felt or a rough patch of road that vibrated though the pedal or a rod bearing spinning. The same applies to modifications, you know instantly whether performance is better or worse after a modification but again wishful optimism corrupts many peoples judgement and due to the cost and effort try to justify the modification. I know right away, get a sinking feeling in my stomach and ask myself if I can live with the outcome or change things back to the way they where and move on. I change it back or make it better, I don't need cup holders, abs, heated seats or mirrors, oscillating vents, blue tooth, back up cameras, air bags, a/c... , heck I don't want any of it on the car, distractions for fairy's that ride in their car instead of drive them. I do need performance, handling, braking and a set-up/drivers seat that allows me to use them, I quickly get used to any improvements and anything that reduces them must go.

Add a modification,accelerate in 3rd from 60mph for 3 seconds, is the car at a faster speed than it was? does braking need to be started sooner and takes longer? Yes= performance gain, no= 0gains, worse= power loss.
Some people call this a butt dyno, but that shows what those people think with and I wonder why those people are modifying cars to begin with. My guess is their friends are into it or they like attention or think everyone else is doing it. Maybe they are where the term ass hat comes from?

Have you ever experienced tunnel vision under acceleration?
It happens when your brain has trouble judging the distance at which to focus your eyes because it has no experience/data/information to process based on the rate of acceleration it is going through, you should adapt in a few seconds if not stop driving fast cars. If you make a modification and experience a touch of tunnel vision it's a good modification.

And in my examples, monitoring gauges under full acceleration is something anyone who drives fast should be able to do, you don't look down at speed, boost, a/f and rpm to know where they are they are already in your field of vision but they are out of focus, you learn to read them that way, needle dials are better than digital read outs for this, you learn needle positions instead of reading numbers but anyone who knows how to drive should be able to learn engine rpm by sound and feel and know where they are without looking at the gauge pretty quickly, if you you need a giant dash mounted rpm gauge and blinding shift light in your face to get this down you probably shouldn't drive anything, ever, not even a lawn tractor.
Yes we should all only do the things we are better than the average other at doing, we all know our learning curves and know whether or not we will pick something up quickly or end up mediocre. If there is nothing you can do better than the average individual can do, go home and kick your dad in the nuts and kick yourself in the ass and try harder.
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