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4.0 Turbo Dyno results

Is that a wheel dyno?The curve is just about as stock,but the numbers are pretty nice though.Ive personally have never understood this kind of mod on a 4x4 rig.The XJ performs perfectly for what it was designed for.On top of this would there be any "actual" perfomance issues(turbo lag) when used on the trail.

Some of us don't really use it for "what it was designed for."

A honda civic was never designed to go 8's, but people do it.

And turbo lag on the trail would be a good thing. 4low + boost = bad.
 
the turbo is sized really well for the 4.0. it spools VERY quickly. in 4low there is more of a load on the motor, so it will build boost quickly. the type of driving i do and more crawling too im easy on the gas pedal.


Actually, there is less load, so less boost.

As for the people saying 8psi max, that isn't really how engines work. As long as the tune doesn't allow any detonation, the failures will happen after a certain amount of torque is being made, or a certain cylinder pressure is exceeded. I doubt that at 8psi, enough pressure is created to pop a head gasket.

Above 8psi I would be thinking about a standalone EFI setup like megasquirt.
 
Anything above 8psi non innercooled with stock cast pistons is scary though, there is very little room for error before you make a few nice ash trays.

Nice job on the YJ, and "because I can" is always good enough of a reason.
 
less lost with the stick than in the AW4 but, for sure, its a powerhouse.
I've read on jeepstrokers.com that the head gasket doesn't become an issue until 16 PSI... for what its worth.
What's the deal with fuel management on this? Ignition? Did I miss these details somewhere?
If you run stock gears in the Rocky Mountains, you know why you'd want a turbo... Try spinning 3000 RPM in third gear and losing speed... it gets old if you like to go fast.
 
And turbo lag on the trail would be a good thing. 4low + boost = bad.


This is what I was thinking, I want to see it in action though....


I was thinking Megasquirt would be an awesome setup for this thing, its not my jeep though so not my decision... I have seen megasquirt used on different vehicles with awesome results though.
 
How many Tangs has he eaten for breakfast?

My '06 Mustang GT puts down 284HP to the ground with just a CAI and a tune. I doubt he'd be eating my "Tang" anytime soon.

To the OP: Nice build though. Good work on the plumbing as it nearly looks like it's meant to be there.
 
My '06 Mustang GT puts down 284HP to the ground with just a CAI and a tune. I doubt he'd be eating my "Tang" anytime soon.

First of all the jeep weighs at least a couple hundred less than a mustang. And assuming a 20% drivetrain loss the jeep's puttin out 240hp and 318 ft/lbs compared to a 2003 mustang gt's 260hp and 302ft/lbs. Sounds like a pretty good race to me.

My camaro puts over 480whp on a heads/baby cam. Heads aren't even ported. (=

Congratulations.
 
First of all the jeep weighs at least a couple hundred less than a mustang. And assuming a 20% drivetrain loss the jeep's puttin out 240hp and 318 ft/lbs compared to a 2003 mustang gt's 260hp and 302ft/lbs. Sounds like a pretty good race to me.



Congratulations.

In the infamous words of Ed Curtis "Talk is cheap. Take it to the track and PROVE your point".

Stock 03 Mustangs run healthy 13's in the 1/4. If the Jeep can run anywhere close to that, then it's a valid claim, otherwise eating stangs is pure bench racing.
 
First of all the jeep weighs at least a couple hundred less than a mustang. And assuming a 20% drivetrain loss the jeep's puttin out 240hp and 318 ft/lbs compared to a 2003 mustang gt's 260hp and 302ft/lbs. Sounds like a pretty good race to me.

Um, If you'll actually read my post you'll see that I'm putting 284hp to the ground, so no drive train loss involved. My '06 is rated at 300hp stock and with the CAI and 93 octane tune closer to 335hp. Let's also take into account that his tranny isn't really meant for any kind of spirited runs and is geared accordingly. My tranny was made with much shorter throws and geared for healthy 0-60 and 1/4 mile times for magazine bragging rights. But if it makes the fanboi in you think that Jeep can beat me, more power to you.
 
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Um, If you'll actually read my post you'll see that I'm putting 284hp to the ground, so no drive train loss involved. My '06 is rated at 300hp stock and with the CAI and 93 octane tune closer to 335hp. Let's also take into account that his tranny isn't really meant for any kind of spirited runs and is geared accordingly. My tranny was made with much shorter throws and geared for healthy 0-60 and 1/4 mile times for magazine bragging rights. But if it makes the fanboi in you think that Jeep can beat me, more power to you.

If by "AMC slush-o-matic" you're referring to the AW4 then you need to go learn. The AW4 isn't an AMC transmission nor is it being used on this YJ. It clearly says, if you could actually read, AX-15, which is a FIVE SPEED MANUAL. Also, where did I say that I thought this jeep would beat you??? "Um", if you'll actually read my post you'll see that I wasn't even talking about your mustang. I mentioned a 2003 just as an example because not everyone drives the newer, more powerful mustang especially with CAI and a tune. Most do not. My exact words were "good race".
 
oh for chrissakes a guy starts out with valid tech discussion and now its a pissing match to see who will have to say "My bad, nevermind" first?
Goddamnit, what about the fuel management and ignition on this thing! Where did you source the turbo? How did the pipes get routed?
Tech, people! Measure your net-dicks elsewhere!
 
--Thank You turboYJ for sharing.--

I Agree with Yossarian19.

Also could you let us know about the fuel, ignition, etc.?

Thanks.
 
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