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Turbo Cherokee?

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Old Oct 25, 2013 | 12:49 PM
  #1  
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Default Turbo Cherokee?

I know, I know, another turbo thread. I was walking back from class today and started thinking about how much stuff would actually go into it for an engineering project. The biggest thing I'm looking at is cost, I need to know if I can afford it or not.

Here's what I know goes into it, please fill in the blanks.

Turbo (T4?)
Manifold
Ducting
Wastegate
Oil Lines
Electronics

What happens to all of the vacuum controlled stuff? Will the HVAC still work?

Thanks in advance
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Old Oct 25, 2013 | 01:09 PM
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This would all be on a renix
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Old Oct 25, 2013 | 02:22 PM
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From: PA KOTUFU!
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All the vacuum stuff must still see vacuum and no boost (HVAC, brake booster, fuel tank purge, CCV). Except the MAP sensor, the IAT sensor, vac/boost gauge, and FIC or FTC for fuel and timing control, they can all see boost. That is a problem with turbo and 'blow thru' the TB, where do you find vacuum only with no boost.

If you allow boost/positive pressure to go to HVAC- you lose controls when under boost like defrost, brake booster- lose function when under boost, fuel tank purge- pressurize your fuel tank when under boost, CCV- pressurize engine when under boost.
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Old Oct 25, 2013 | 04:57 PM
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See inside for a turbocharged 4.0 build thread: http://www.naxja.org/forum/showthread.php?t=1031285
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Old Oct 25, 2013 | 06:48 PM
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Originally Posted by CobraMarty
All the vacuum stuff must still see vacuum and no boost (HVAC, brake booster, fuel tank purge, CCV). Except the MAP sensor, the IAT sensor, vac/boost gauge, and FIC or FTC for fuel and timing control, they can all see boost. That is a problem with turbo and 'blow thru' the TB, where do you find vacuum only with no boost.

If you allow boost/positive pressure to go to HVAC- you lose controls when under boost like defrost, brake booster- lose function when under boost, fuel tank purge- pressurize your fuel tank when under boost, CCV- pressurize engine when under boost.
What did you guys do for the two S/Ced jeeps?

And how necessary is an intercooler for a system running at 4psi? I suppose the same question for the stock tune also.
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Old Oct 25, 2013 | 07:05 PM
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I looked up some of the bigger parts and it's looking like this would cost around $1000 if I were to go with a godspeed t3/t4 off of fleabay. I know you get what you pay for but for wanting to run only 4psi how big of a deal could it be?
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Old Oct 25, 2013 | 08:11 PM
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We are able to plumb them under the TB but before the SC.

No intercooler needed at 4 pounds boost, as long as your IATs stay under 200 degrees.
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Old Oct 25, 2013 | 09:12 PM
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Originally Posted by CobraMarty
We are able to plumb them under the TB but before the SC.
Ok, so I could do the same with a turbo, right? Plumb them in the intake ducting before the turbo?

If I don't end up doing this for a project, I may still do it when I get out of school. It seems simple enough
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Old Oct 26, 2013 | 05:29 AM
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There won't be sufficient vacuum there to work the accessories. The vacuum is created after the TB. Maybe an electric vacuum pump would work?
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Old Oct 26, 2013 | 05:59 AM
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If you have to ask if you can afford it you probably can't.
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Old Oct 26, 2013 | 10:08 AM
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Originally Posted by CobraMarty
There won't be sufficient vacuum there to work the accessories. The vacuum is created after the TB. Maybe an electric vacuum pump would work?
I had that thought too. As a school project it would definitely have it's challenges.


Originally Posted by RubberSideUp
If you have to ask if you can afford it you probably can't.
Or I like to know every little detail about any project Before I jump into it
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Old Oct 29, 2013 | 01:41 PM
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Normally for vacuum stuff like the brake booster and vacuum canisters there are check valves inline. There is low manifold vacuum at WOT on an N/A engine anyway so usually there is already something in place.
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Old Oct 29, 2013 | 04:08 PM
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Originally Posted by PseudoSport
Normally for vacuum stuff like the brake booster and vacuum canisters there are check valves inline. There is low manifold vacuum at WOT on an N/A engine anyway so usually there is already something in place.
XJs just have a reservoir hiding in the front bumper. No check valves.

For some reason I thought that vacuum system and CCV stuff was just plumbed to right before the turbo
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Old Oct 30, 2013 | 07:30 AM
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"Or I like to know every little detail about any project Before I jump into it" It'll still throw you a surprise here and there. Which is half the fun.
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Old Oct 30, 2013 | 08:45 AM
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Originally Posted by RubberSideUp
"Or I like to know every little detail about any project Before I jump into it" It'll still throw you a surprise here and there. Which is half the fun.
Thanks for the incredibly enlightening posts.
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