What mods should i do to my 2001 tj

A

amagedson

New Member
Joined
Aug 30, 2017
Messages
16
Location
US
I have a completely stock wrangler tj and I'm in the process of replacing all the deteriorating gaskets and adding some mod to help it run and drive better. The first thing i wanted was a cold air intake, but researching i read that it was a waste of $$$. So I'm asking what mods are actully going to get me better profomance ie. Hp, mpg????

Sent from my SAMSUNG-SM-G930A using Tapatalk
 
Cold air intakes are a huge waste of money on our TJs, you'll gain nothing at all from them.

A decent exhaust might give you a few more horsepower, but short of superchargers or turbos, there isn't many things you can do to the 4.0 to gain horsepower. There are no "performance ECUs" on the market that work with our TJs, the headers don't give you any gains as none of them are actually full headers, and there really isn't anything you can do to gain any usable horsepower unless you're ready to go forced induction or do internal engine work.

The best mod you could do to gain a better power band (especially with bigger tires) would be to re-gear it. That wouldn't give you more horsepower, but it would make for a much more usable power band, which would definitely make it feel as if you've gained more power.

You could also stroke it, port and polish the head, etc., but those are all very expensive, and you may as well just supercharge or turbocharge it at that point (which is about $2500 or so for a kit).
 
  • Like
Reactions: StG58, amagedson and JP98
HEMI.jpg


Other than that, make sure it is running at it's peak performance; new air filter, spark plugs, wires, coils (if needed) cap and rotor (if you have them).
If you are, or planning on larger tires, a gear swap is a must do. A Jeep engine is what it is, made to putt along the hwy and crawl off road.
 
  • Like
Reactions: StG58 and amagedson
The 4.0 is a very good motor. Bullet proof. It provides plenty of power, can cruise at 75 without a problem and is a great off-road power plant. All you really need to do is make sure the Jeep is geared properly and you'll be happy.
 
  • Like
Reactions: StG58, amagedson and Chris
x4 on what Chris said too...There are plenty of write ups about gaining extra HP or better gas mileage.(most aren't worth even trying)...Better gas is more a case of how you drive (heavy right foot lol) I gave mine a good solid service including engine oil flush and re-fill, plus oil and air filter change, sparkys and distributor cap with new HT leads.....I gained heaps after the POV hadn't serviced it in years.
 
  • Like
Reactions: StG58 and amagedson
Most of the time I would fully agree with our previous posters... in this case I agree slightly but disagree as a whole.

Yes, doing a CAI alone is minor. Header alone is minor, yet recommended. And a cat back alone is minor. BUT, the combination of all 3 actually makes for a very noticeable improvement! Doing them individually you will notice minor changes in sound, response, and efficiency but one without the other two will bottle neck the performance upgrades. But when coupled together the improvement is undeniable.

Due to the manufacturing flaw of the TJ exhaust manifold almost everyone experiences a failure at some point. It will sound like a minor tick or low end knock. Replacing it with a higher gauge steel header is a worth while investment.

I can't speak to all variations of these products but I fully stand behind Banks products and know several others who only buy Banks and have noticed significant upgrades!

x5 on the regearing. Nothing quite returns your jeep to its ideal performance better than running the appropriate gearing for your set up.

Edit: Post regear I was happy to see a decent return in power and throttle response but I was still unhappy with my fuel economy. 10-11mpg. A few months later I finished off my Banks system with the Banks headers to replace my cracked manifold. I immediately noticed the most significant improvement in response and my economy jumped to 15.5-16mpg as my DD. Highways @ 65-70mph and back roads around 55mph.

Sent from my iPhone using Tapatalk
 
Last edited:
  • Like
Reactions: amagedson
amagedson said:
I have a completely stock wrangler tj and I'm in the process of replacing all the deteriorating gaskets and adding some mod to help it run and drive better. The first thing i wanted was a cold air intake, but researching i read that it was a waste of $$$. So I'm asking what mods are actully going to get me better profomance ie. Hp, mpg????

Sent from my SAMSUNG-SM-G930A using Tapatalk
Click to expand...

You have a stock TJ so there is no need to re-gear unless you increase your tire size, which wasn't one of the things that you mentioned.

What are you *not* getting out of your TJ that is making you look for performance upgrades?
 
  • Like
Reactions: jeepXcore and JMT
Don_L said:
Most of the time I would fully agree with our previous posters... in this case I agree slightly but disagree as a whole.

Yes, doing a CAI alone is minor. Header alone is minor, yet recommended. And a cat back alone is minor. BUT, the combination of all 3 actually makes for a very noticeable improvement! Doing them individually you will notice minor changes in sound, response, and efficiency but one without the other two will bottle neck the performance upgrades. But when coupled together the improvement is undeniable.

Due to the manufacturing flaw of the TJ exhaust manifold almost everyone experiences a failure at some point. It will sound like a minor tick or low end knock. Replacing it with a higher gauge steel header is a worth while investment.

I can't speak to all variations of these products but I fully stand behind Banks products and know several others who only buy Banks and have noticed significant upgrades!

x5 on the regearing. Nothing quite returns your jeep to its ideal performance better than running the appropriate gearing for your set up.

Edit: Post regear I was happy to see a decent return in power and throttle response but I was still unhappy with my fuel economy. 10-11mpg. A few months later I finished off my Banks system with the Banks headers to replace my cracked manifold. I immediately noticed the most significant improvement in response and my economy jumped to 15.5-16mpg as my DD. Highways @ 65-70mph and back roads around 55mph.

Sent from my iPhone using Tapatalk
Click to expand...
I can support just about everything you are saying but one thing. You can't truly accredit the banks header providing you that addition 4.5-5mpg better. If the header was cracked, that in itself will affect the gas mileage. Had you replaced it with a stock manifold it would have yielded the same results. Mine is currently cracked, and I will be installing a header. For the purposes you listed above, every little bit helps. I know if I replaced my cracked manifold with a new manifold it would yield similiar if not the same results. The main benefit of replacing the manifold with a header is the fact it won't crack on you 30k miles from bow ;).
 
JamesAndTheSahara said:
I can support just about everything you are saying but one thing. You can't truly accredit the banks header providing you that addition 4.5-5mpg better. If the header was cracked, that in itself will affect the gas mileage. Had you replaced it with a stock manifold it would have yielded the same results. Mine is currently cracked, and I will be installing a header. For the purposes you listed above, every little bit helps. I know if I replaced my cracked manifold with a new manifold it would yield similiar if not the same results. The main benefit of replacing the manifold with a header is the fact it won't crack on you 30k miles from bow ;).
Click to expand...

Completely agree, I worded it wrong. I do believe that replacing the header, regardless of the brand, is what brought my fuel economy back to the normal range. But in terms of power and throttle response I felt a noticeable change from when we got the jeep in 2003 and when I began driving it in 2010. The headers cracked in 2015-2016 as that is when I noticed a significant decrease in fuel economy.


Sent from my iPhone using Tapatalk
 
  • Like
Reactions: JamesAndTheSahara
Don_L said:
Completely agree, I worded it wrong. I do believe that replacing the header, regardless of the brand, is what brought my fuel economy back to the normal range. But in terms of power and throttle response I felt a noticeable change from when we got the jeep in 2003 and when I began driving it in 2010. The headers cracked in 2015-2016 as that is when I noticed a significant decrease in fuel economy.


Sent from my iPhone using Tapatalk
Click to expand...
Gotcha! My exhaust manifold has always been cracked. I am going to be putting in a header very soon. Also pretty tired of the clicking noise ;).
 
  • Like
Reactions: Don_L
JamesAndTheSahara said:
Gotcha! My exhaust manifold has always been cracked. I am going to be putting in a header very soon. Also pretty tired of the clicking noise ;).
Click to expand...
My question was going to be how did you know it was cracked, but with your clicking comment I'm assuming it's making some noise? And it's ok to drive with a cracked manifold? My jeep just starting a ticking/ knocking noise. Trying to figure out why.
 
Kathy said:
My question was going to be how did you know it was cracked, but with your clicking comment I'm assuming it's making some noise? And it's ok to drive with a cracked manifold? My jeep just starting a ticking/ knocking noise. Trying to figure out why.
Click to expand...
Its something I need to fix that causes a poor fuel economy & performance. I know its mine for two reasons: 1. Its acceleration dependent & 2. I've located several cracks in it. The 97-99 TJ's were known for their exhaust manifolds cracking.
 
  • Like
Reactions: Kathy
I wouldn't trust anything that came out of Fourwheeler magazine. Those guys have paid product placement by numerous vendors (that's how they stay in business).

But hey... It's your money, if you believe that throwing the money into a CAI and a new exhaust manifold (not headers, since they aren't full headers) will make a difference, I'd love to see the back-to-back (same exact day) dyno charts that proves you gained any real power.

The Jeep engineers themselves have stated on the forums that when they designed the 4.0, getting enough air was not an issue with the stock airbox. This may be the case on some vehicles, but on the 4.0 engine, it is not the case whatsoever. The stock airbox flows more air than your engine is even capable of using. So unless you plan on adding larger valves, a larger intake manifold, and a larger throttle body, all that perceived extra air you're getting from a CAI, can't even be used!
 
By the way, it's worth mentioning that the 2000+ exhaust manifolds don't crack like the earlier ones (well, not as easily at least). The came can't be said for Banks manifolds (or similar). My Banks manifold (that I had years ago) cracked after 1 year! Those things are pieces of garbage to say the least.
 
  • Like
Reactions: Tj04 and Kathy
Chris said:
By the way, it's worth mentioning that the 2000+ exhaust manifolds don't crack like the earlier ones (well, not as easily at least). The came can't be said for Banks manifolds (or similar). My Banks manifold (that I had years ago) cracked after 1 year! Those things are pieces of garbage to say the least.
Click to expand...

Banks manifolds have had a bad reputation for cracking in the past decade. It wasn't until the last 2 or 3 years that they changed up their design and overcome previous design flaws.


Sent from my iPhone using Tapatalk
 
@ Kathy "And it's ok to drive with a cracked manifold?"

Well yes and no. While it is usually ok to drive with it cracked you have a great risk to yourself from the exhaust gas getting into the passenger compartment. Also if it is leaking at the gasket and not cracked, it will damage the head over time. If it were me I would replace it as soon as possible.
 
  • Like
Reactions: JamesAndTheSahara and Kathy
Top Bottom
Back