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Programming for boost questions

A Split Second FTC1 w/ built-in 2-bar map would fit the bill. It can measure and retard boost. You could disco the CTS(@t-stat housing) and then make your own map without pcm interference. You will have a check engine light for the cts, though. I currently have a unichip installed, but unconnected, with a similar harness(which I think is the way to go with piggybacks/controllers and obd2 vehicles).
 
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gradon said:
You could disco the CTS(@t-stat housing) and then make your own map without pcm interference. You will have a check engine light for the cts, though.
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? You should be able to modify the FTC1s maps without any issues with the factory PCM.

A good piggyback system works great as long as it's setup and installed properlly. With the AEM I can modify my fuel and ignition maps even while driving. This is because the factory ECU has no idea it's even there.
 
CanMan said:
So I picked up a Thunderbird SC and have started fabbing up some brackets, mounts, and so forth. These SC's are set for 12 lbs of boost stock. Im going to have a larger pulley made(or find one) so I can run less boost(6-8lbs). The TB will be on the inlet side of the SC.

Other mods are small(bored TB, 99+ intake, no cat, flowmaster 40 series). 1998, AW4, lift, gears, 33's ect..

Ive been reading about how the Chrysler computer is not self adapting, and by adding more fuel pressure, bigger injectors, and ignition mods wont work. True?

Im seeing Kenne Bell does an Optimizer 2 computer reflash/relearn, worth the money? They also do a Boost-A-Pump, worth it over an FMU?

What to do with the single feed fuel line? No return needed?

What components will I need to make this thing run right? Larger injectors, more fuel pressure, colder plugs gapped correctly, timing retarded, piggyback computer(Apexi, Megasquirt, ect..), FMU, 3bar MAP sensor, ect..?

Any and all help would be appreciated. Id like to get this thing done in the next few months.
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That SC makes 12 psi on a supercoupe. Even with the stock pulley, it'll make a different amount of boost on the jeep 4.0 Different motors, different induction flow, different sized crank pulley. I believe the crank pulley on the jeep is something like 7-1/4" on the grooves. If you use a stock pulley from a 94-95 supercoupe you'll make around 6-7 psi. If you use a pulley from a 89-93 SC you'll make about 8 psi.
 
Mezzer8 said:
That SC makes 12 psi on a supercoupe. Even with the stock pulley, it'll make a different amount of boost on the jeep 4.0 Different motors, different induction flow, different sized crank pulley. I believe the crank pulley on the jeep is something like 7-1/4" on the grooves. If you use a stock pulley from a 94-95 supercoupe you'll make around 6-7 psi. If you use a pulley from a 89-93 SC you'll make about 8 psi.
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I did the math(assuming its right) and it'll be right at 9lbs of boost with the 4.0 balancer pulley and the stock SC pulley. The M90 is the later version, the 94-95 model year. If I run a FMIC it'll be less due to the drop in pressure through the IC. Im not concerned about the amount of boost at this time really.

Ill do the AEM comp, as it seems easier to mess/tune with, its cheaper, and there is someone else here using the same setup.

Some progress.


Photo-0429.jpg
 
CanMan said:
Photo-0429.jpg
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I'm really enjoying the build on this but, I thougt I would add my .02. While your still in the fabrication stage you might think about adding another idler pully so that the belt has more wrap around the pully. It's really needs to be more like the wrap on the alternator. It would suck to have gone through all this trouble to design and build this project and then be dealing with belt slippage issues.
 
Cody90XJ said:
I'm really enjoying the build on this but, I thougt I would add my .02. While your still in the fabrication stage you might think about adding another idler pully so that the belt has more wrap around the pully. It's really needs to be more like the wrap on the alternator. It would suck to have gone through all this trouble to design and build this project and then be dealing with belt slippage issues.
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The idler pulley next to the SC got replaced with a smaller one, belt wrap is better than what it looks like in the picutre. I gots it covered. ;)
 
Im getting closer to purchasing the computer and electronics side of this build.

Ive found a set of 1995 Tbird Supercoupe injectors.

They are rated at 36lbs, between 30-40psi fuel pressure.

Are they going to work with the higher pressure of the late model XJ?

Someone schoole me! :roll:
 
I have reman 36# injectors that i paid $170 for. They were used for 10mins. $100 shipped and they are yours.
 
I'll throw this out there...

Syclone/Typhoon/Sunbird turbo computer.

It's a standalone, ECU only (no trans controls) that was buil for boost, and built well. The stock Sy/Ty computer is a batch fire, MAP regulated unit with an exceptional built in boost controller. Moates.net sells flashing equipment/software for around $300, called an Ostrich.
You can pick up a new computer from about any parts store for <$100 and get a 4.3 Harness (OBDI of course) from a junk yard for nothing, and all related sensors. There's no CPS, just a CMS, and it has knock control. I would like to build a turbo stroked (someday, which means it'll never happen) and that's the route I'd go. The 3rd gen F body guys run them a lot when they switch to F/I, since they can be setup for 4-6-8 cylinders.
 
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