Michro Tech LT 10 x4
 

Guys I have an FB 12a ported bridge pin etc, it has it. Strong 12a with a 76mm turbo. This is the issue I'm having. If I tried to start the car in the morning been outside, there is not a way to get this car started. I mean I have tried everything possible. New alternator and battery. But, if I leave it alone and go to work and come back in the afternoon it fire right up when you show the key to it. I don't know what is causing this. Is it a cold start tuning issue? Not enough fuel, it has 4 1600 injectors. Now if I get it started in the afternoon and parked it in my garage were the temperature ranges around 83*f, the car tries to fire the first time but I keep trying and it fires right up. I don't get it, what's going on here. There is spark at all times. Coils are Bosch. Any help I will appreciate it.


Edgar

Are you able to look at the maps with the handset or laptop?

Yes

Check the base map thread at the top of this section and see if your screen 20 and 22 are similar or adjust mixtrim in 5% increments and see if it starts at the prob temp.
Take note of your current settings so you can reenter if you need to.

Mixtrim remember is only for troubleshooting. It effects the entire curve.

In the morning before you leave for work, plug in your handset/laptop and take a look at the t_wat table. Bump the fuel about 10% at the bin showing the current temperature (cursor should already be there) and increase surrounding bins say, 5%. Now do the same for the crank map.

Bridgeports take a LOT of fuel to start up, especially in cold weather. Sounds like the startup maps have not been tuned.

So myself and my tuner have tried everything on this car. I moved the coolant sensor from front of the thermostat to behind it so it will read the coolant temperature faster. We took fuel away on the coolant, as much as possible. Well, waited until the next morning. Coolant/water temp was as usual 31*C which is 87*F. We took fuel away on the lower map or to started it, nothing, we gave it fuel nothing,again it will not fire, it will try but then is just spinning and don't want the battery to go down on voltage. So my tuner says that due to the motor been a bit low on compression is the reason, 65 front and 75 rear. If that is the reason, why is it when I go back to it at around 3 hrs later the motor fires up just showing the key to it. If this statement is correct then it should not fire either in the mornings or afternoons. So I guess the only time I can use this car is in the afternoons, LOL. I'm lost.


Edgar

Your compression is low. Add some MMO in to the mix next time it won't start see if it helps . Have you considered using smaller injectors for primary?

Did not work. So these engine when they are low on compression they will have this problem when they are hot, no way they will fire. But when cold and a bit of oil thru the throttle body will fire. So this tells me it is not mechanical. I'm going to try a set of 850cc injectors on the primary side.

Edgar

Don't use MMO for anything. Read the datasheet. It is just wax mud and not suitable for a premix or lubricant.

If you want to use oil to raise compression, then just two stroke oil in the chambers will do the job fine.

As for the startup, why are you REMOVING fuel? Your description of the car cranking and cranking, almost firing, means that the engine is too lean. And if it has lower compression, then that calls for even more fuel.

Is this a new engine? Is this a new tune or has everything been working previously?

I agree, 4 x 1600 cc injectors are a bit ridiculous for that engine. That's about 750Hp worth of fuel capability. You will find it a much easier to tune if you go to smaller primaries like the 850CC units you mention. Even that's a bit big. The Microtech doesn't have much resolution down low due to the way it stages so with 1600CC injectors you'll have a hard time leaning it out at low throttles.

My motor is not fresh it has been a bout a year or more since built. I pre mix with the 2 cycle oil I think is call castor 927. We took fuel out nothing we gave it fuel and nothing. But I come home in the afternoon and show the key to it and fires right up!!
This is a pretty strong engine, with a 76 mm and 81 a/r on the two step launch at 8400 and just putting the gears in runs 10.92 at 128 mph. And once hot it will fire up right away, so, again I'm lost.

When you were adding fuel, how much did you add?

Cranking pulsewidth cold on a bridgeported engine with 4 x 1600CC injectors should be around 8mS. Yes, that is a LOT of fuel.

Where are your injectors positioned on the 12A? Going to be a custom manifold, so if the injectors are way up there away from the ports, it's going to take even more fuel due to wall wetting.

Injectors are under the throttle body. Is a 8 injector type but I only have a 4 firing. Is on a ported four hole racing beat. The throttle body is a Pro Jay.

Can you post up your crank and water maps.

Here are a couple of pictures from the hand sent. You guys tell me what you see.

Can you post up screen 20 and 22 from your map?
Does the car run perfectly fine above this temp?

Yes, once warm it runs ok. But if the weather is a bit cold then the car starts to fall down like is leaning out. But if the weather gets warm it runs like a champ. Don't know how to do that.

search for an online user manual as it will come in handy.
press down arrow until you hit screen 20.
then use left and right to view the different temp ranges.write all the settings down.
then down arrow to screen 22 and repeat.
I havent used the handset before but looks like there are no temp corrections for 24C so its way too lean to start.
post screen 20 and 22 settings so i can tell for sure.
MAKE SURE YOU DO NOT HIT MODE BUTTON.

here are the numbers from page 20 and 22.

Page 20
Water 18*C +10%
11*C +26%
05*C +35%
-01*C +46%
-09*C +57%
-17*C +60%
-25*C +63%
124*C +00%
99*C +00%
82*C +00%
68*C +00%
60*C +00%
46*C +00%
38*C +00%
31*C + 00%
24*C +00%




Page 22
Crank 31*C +00%
24*C +00%
18*C +00%
11*C +00%
05*C +20%
-01*C +21%
-09*C +23%
-17*C +25%
-25*C +27%
124*C +00%
99*C +00%
82*C +00%
68*C +00%
60*C +00%
46*C +00%
38*C +00%



These are the numbers from the handset. Let me know what you see here. Thanks for the help:

Edgar

Wow what a mess:icon_tdow
With numbers like that im surprised it runs at all.
Getting these maps sorted will be pretty straight forward but i suspect the rest of the map will be a mess too and worst case scenario could destroy the engine.
You need to either find a decent tuner or get a wideband,instruction download and willing to have a go.
Personally id take it to an expert but ill try and help if you are willing to take the risk.

Should be able to get it started and running no problems if everything else is ok.
Boost maps should be really done on the dyno to get the most out of it safely.

This is how this car starts. I try in the morning. Nothing happens just spin. I leave it alone. Around 4pm when I come from work I get in the car put the key and turn the key, motor fires right up. But it take a while to get it to act right. But if I drive it and get on it, at 14 psi this thing is a handful and I look at the Air fuel ratio gauge and is showing 11:1 to 11:50 at full throttle, sometime it drops to 10:1. This motor will suck a 15 gl fuel cell in no time, it burns fuel like crazy. So what do I need to do.
Edgar

OK so what water temp does it start and fail to start at?
Download the manual and set the tps.
Post up screen 1 and 3.

TPS is set up. I can see the * and full throttle 99% off throttle 0%. mornings 21*C to 31*C would not start. Afternoon 35*C - 37* fires right up.

Go to screen 30 Mixtrim and change value to +20% and try to start at prob temps.
If no start try keep adding +5%.
As aaron mentioned it changes the whole fuel map but will give you an idea of how much extra fuel will need to be added to the map for it to start with mixtrim back at 0.

So I did what you said. Went to page 30, Mixtrim. It was at 0%. I gave it 20% like you said. Lock it down. I turn the key and it was trying to fire and then suddenly it fire up 29*c. I let it warm up and A/F ratio is in the 12.50-70 and it loves it. I can tap the throttle and it is clean with no stumble. Motor responds faster. So the question is, do I have to put the Mixtrim back to 0%.

Edgar