4.0 build help

4.0 01 TJ

New Member
Original poster
Oct 21, 2021
Looking to build the piss out of a 2001 4.0 for my TJ. 4.6 stroker kit planned, and turbo. What is available for tuning?

I just rebuilt an engine for it but the block was too far gone (scored cylinders) so I am getting a junkyard one (2000 year) and going to bore and stroke it for sure. 0331 non tupy head unfortunately.

Thinking about aftermarket efi, like a holley sniper, and msd coil packs possibly. Will be a custom turbo kit looking to push around 15psi. Any part recommendations are greatly appreciated
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Why bother with an aftermarket stand alone ECU if you are sticking with the stock form factor motor? You'll have to go all custom gauges amongst other things with the ones you've mentioned Flyin Ryan has tuned a bunch of turbo builds with HP tuners and stock PCMs. @Jezza is tuning his own build using an AEM Infinity that I believe keeps the stock ecu to run the gauges and stuff.

I would ditch the non-TUPPY 0331 head if I were you. Is your old head 0331? Be aware there was a year break where TJ motors weren't bolt in compatible. Different mounting brackets or something like that. Not sure the year break off the top of my head but it's somewhere around your year.

What turbo are you planning on? PSI numbers are useless without saying what the compressor is making said boost. Are you fabbing your own install?