Increasing power from my TJ
- Thread starter Franz
- Start date
Popcorn for breakfast it is.
To answer your question, not really without serious mods.
To answer your question, not really without serious mods.
Would be helpful if year and emgine were listed. Colojeep pointed out OP has a 2.4L. Ammended recommendation. Sell 2.4L TJ and buy 4.0L TJ.
Yes you can make more power from a 4.0L. It won't be a huge amount unless you go stroker, supercharger or turbo, but you can find 20-30hp without tearing the motor apart. The 4.0L isn't all that powerful and driveline losses are around 30%.
If you are on larger than factory tire sizes, regearing is the first thing you need to do. Mainly to bring the final drive ratio back into alignment with the narrow powerband of the 4.0L.
There is a bolt on dyno series thread here. It was with an earlier TJ. There are differences between years but the core concepts remain the same.
A TJ 4.0L does benefit from a cold air intake.
A TJ 4.0L will benefit from a catback exhaust.
A TJ 4.0L will benefit from a set of 1.7 roller rockers but can have pushrod interference.
A fuel return system adds some power as well.
Headers don't do much with the early models, but the later ones with precats can pick up some nice gains in the 2000-3500rpm range from short headers while retaining the precats. Only 5hp or so at peak at 4500 with these though.
HP Tuners is the way to go for modifying the programming. Advancing the timing on WOT 3°-6° is an easy mod. You need a wideband O2 to adjust fuel without flying blind.
Some mods don't do much or anything unless the original part requires replacement. 4 hole fuel injectors for instance.
Yes you can make more power from a 4.0L. It won't be a huge amount unless you go stroker, supercharger or turbo, but you can find 20-30hp without tearing the motor apart. The 4.0L isn't all that powerful and driveline losses are around 30%.
If you are on larger than factory tire sizes, regearing is the first thing you need to do. Mainly to bring the final drive ratio back into alignment with the narrow powerband of the 4.0L.
There is a bolt on dyno series thread here. It was with an earlier TJ. There are differences between years but the core concepts remain the same.
A TJ 4.0L does benefit from a cold air intake.
A TJ 4.0L will benefit from a catback exhaust.
A TJ 4.0L will benefit from a set of 1.7 roller rockers but can have pushrod interference.
A fuel return system adds some power as well.
Headers don't do much with the early models, but the later ones with precats can pick up some nice gains in the 2000-3500rpm range from short headers while retaining the precats. Only 5hp or so at peak at 4500 with these though.
HP Tuners is the way to go for modifying the programming. Advancing the timing on WOT 3°-6° is an easy mod. You need a wideband O2 to adjust fuel without flying blind.
Some mods don't do much or anything unless the original part requires replacement. 4 hole fuel injectors for instance.
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Oh... in that case the bright side is that he's aleady making 30hp more than a 2.5L?
I don't think much can be done for that motor.
WTF ! he could put in a 20 HP honda lawnmower engine and have more power
I don't even think a FRAM filter can help him
There is one way to give it more power...
WTF ! he could put in a 20 HP honda lawnmower engine and have more power
yes, I could put a Honda engine and replace the engine oil with olive oil
I was going to post a link to @Jezza ’s really good dyno series for 4.0 bolt mods OP (mostly the stuff @GoldenGorilla mentioned above), but I see you have the 2.4L. Gearing down (numerically higher gears) like where @macleanflood was probably going) may help but I would V8 swap a 4 cylinder TJ. I wonder what the rules are about that sort of thing in Italy?
Olive oil only works in FIAT motors. You'll want sesame oil.
In Italy it's not possible to change the engine... I would no longer have the homologation to drive it.
So gearing yes.
The Dodge Neon SRT 4 2.4 shares the internals with your engine block. Has a turbo. Does many hundreds of horsepowers.
Technically it would be the same engine...
-Mac
yes at this point to really make a difference I could put a turbo kit or recover one from a neon
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