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Guest Message by DevFuse
 

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XT Turbo to high bost


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8 replies to this topic

#1 Rossi86

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Posted 03 September 2012 - 10:04 AM

Looking to convert my 1986 turbo XT from an airflow meter, "the flapper" to a Mass air flow censer. Whats the best way to make it work, with out going to a stand alone system?

#2 GeneralDisorder

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Posted 03 September 2012 - 01:37 PM

You can't without changing to an entire 87+ engine harness and ECU. Your ECU doesn't understand the sensor output of a hot-wire MAF.

GD

#3 WoodsWagon

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Posted 04 September 2012 - 08:22 PM

Swapping the flapper door maf to a hot wire one won't gain you much if anything.

The flapper door MAF cars are better for cranking up the boost because fuel cut is controlled by a pressure switch. Unplug the pressure switch and it will never hit fuel cut. Later hot-wire maf cars use the measured volume of air going in to calculate an overboost situation and hit fuel cut. No easy way to get around that.
There's two pressure switches on the passenger side strut tower. One is for the "turbo" light in the dash, the other is for fuel cut.

Go over all the coolant hoses including the small ones to the turbo and the intake manifold for cracks, swelling. or soft feeling. If you spring a coolant leak the headgaskets will pop by the time you notice it. The cooling system needs to be in top-notch shape before you try getting more power out of the engine.

I would highly recommend installing an intercooler or water/meth injection system or both before turning up the boost. They will give you a much greater margin of safety before the engine blows up. Which it most likely will by the way.

These are not stout engines and they got away with not having enough power to hurt themselves. Turn the boost up to where it starts making real power and the weak points will show themselves. Heads, headgaskets, rods, pistons, ect. When you're done grenading it you can swap to an EJ series engine and start making reliable power.

Edited by WoodsWagon, 04 September 2012 - 08:25 PM.


#4 Rossi86

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Posted 09 September 2012 - 05:25 PM

Sounds like what I planed on doing before I saw an 88 with MAF. It's nice to know the AFM is not easily switched to the MAF. I will be changing all the hoses to neoprene before I modify the boost control. I was looking a inter coolers from a VW. And a water methanol kit from snow performance.

#5 john in KY

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Posted 09 September 2012 - 06:31 PM

Easiest way to increase boost is to "fool" the waste gate controller. Find its vacuum line, slice in a T-fitting and attach about of 30 inches of vacuum line to the T. The 30 inch line just dumps into the atmosphere. Got to use a boost gauge to find the optimum length. I ran 12 pounds of boost for 100K miles without a problem in a 90 turbo wagon.

#6 djellum

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Posted 09 September 2012 - 10:43 PM

the guys over at the XT forum ussually suggested installing an exhaust temp sensor. theory was that as you boost up the heat increases and having a temp sensor would tell them when they were getting into the red zone.

im guessing they installed it in the Y somewhere. I think they make actual combustion chamber temp sensors but you have to machine the heads to accept them.

also they used ford thunderbird supercoupe injectors if they didnt modify the stock ones. the stock injectors arent rated for much more than the motor puts out, so you will run lean as you start modifying if you dont pay attention to your injectors. I beleive there was a place in washington that would rebuild and spec your injectors for about $30 per injector.

I havent had a turbo XT in years, but I would see to the fuel delivery, head gaskets, intercooler, etc before messing with the boost. You want to make sure the motor is ready for it or it will just burn it out. of the mild builds I have heard of they use early legacy turbos to get an extra 2 psi or so. dont throw on a WRX turbo or something like that, its just too much. Most all of the ones that tricked them out used megasquirt to manage the engine.

#7 Rossi86

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Posted 29 September 2012 - 08:45 AM

Upgrading the ignition system with new performance MSD wires, and a MSD blaster coil. Got a surprise with a nice clicking noise that was the arking on cylinder #2, The new wires were needed why not go big... I got a K&N air filter and it's amazing the difference in responsive nice, MPG, and hp. Then the wire burnt through.

#8 Rossi86

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Posted 13 October 2012 - 09:06 AM

The ignition improved fuel economy and torque substantially. It formed an exhaust leek that needs repair. I'm going with a hole magnaflow turbo back exhaust. Any one use Magnaflow parts on there XT? Likes diss-likes?

#9 Rossi86

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Posted 28 October 2012 - 09:02 AM

What exhaust parts will inter change with the XT turbos, the newest one I can get? I don't like galvanized, and not all of it is offered by Magnaflow.




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