4.0 cam upgrade

[robo512]

Hey everyone, I am in the process of rebuilding my 2002 TJ's 4.0 and would like to put a better than stock cam in that will allow me to keep the stock tune. Any recommendations? Doing a standard rebuild with a 30 over bore. And no I do not want to stroke it I don't have the money for a new crank/rods/tune/etc.

 

[Kid Mechanic]

What do you mean by better than stock? An aftermarket with the same specifications? Changing cam specs would require a different tune or it might not operate correctly. Stick with the same grind on your replacement cam as what is in it now.

 

[robo512]

What do you mean by better than stock? An aftermarket with the same specifications? Changing cam specs would require a different tune or it might not operate correctly. Stick with the same grind on your replacement cam as what is in it now.

I just meant a cam with different specifications for a bit more torque/power that the stock tune would still be able to account for safely

 

[Kid Mechanic]

I’m familiar with tuning manually, swap a cam, tune the carb, adjust the timing, etc.
With computer controlled engines, my understanding is you need to flash tune to compensate for any changes like, what you want, or it might not run right or would be not getting what you want from the changes made. Other changes to increase fuel might be needed, ie; injectors, to maximize anything you wanted from a cam swap. Then there is larger throttle bodies, better flowing heads, exhaust manifolds and it just keeps snow-balling from there.

 

[Brianj5600]

I would call Russ Pottenger at Bishop-Buehl Racing Engines about a cam. He builds a lot of 4.0 engines and could help you with compression ratio with his drop in cam. Stock 4.0s low compression and the piston to low in the cylinder. Both cost efficiency. I'm guessing you want to run 87 oct gas and he will probably ask.

Russ Pottenger
Bishop-Buehl Racing Engines
Work (626) 967-1000
Cell (626) 673-2203
Email/PayPal: [email protected]

 

[Wildman]

https://hesco.us/products/30810/val...97/6-cylinder-camshaft-h264-14b6#.YKNTLnmSmUk
You will probably need to talk to someone like Flyin Ryan Performance to tune it if you change the cam.

https://www.summitracing.com/search/part-type/camshaft-kits/make/jeep/engine-size/4-0l-242
https://www.compcams.com/products/c...199-258-c.i.-4.0l-6-cylinder-(1999-2006).html

 

[Rubicon88]

I just meant a cam with different specifications for a bit more torque/power that the stock tune would still be able to account for safely

You want this cam!!!
Simple.
No miraculous stuff needs done in addition to the cam.
Buy cam...install. I'd advise putting in new lifters though since you've gone that far. Hell even stock lifters are fine...just put fresh lifters in.

https://www.compcams.com/xtreme-4x4-205-213-450-450-hydraulic-cam-for-jeep-amc-6-cyl-1999-2006.html
This is a nice TQ/HP bump over stock but still plays nice with everything. Stock springs etc....

It's a 450/450 lift
Stock on a 2002 is
408/414

The above comp cam is about the max you can do and still retain the stock components whilst playing nice.

Good luck

 

[robo512]

You want this cam!!!
Simple.
No miraculous stuff needs done in addition to the cam.
Buy cam...install. I'd advise putting in new lifters though since you've gone that far. Hell even stock lifters are fine...just put fresh lifters in.

https://www.compcams.com/xtreme-4x4-205-213-450-450-hydraulic-cam-for-jeep-amc-6-cyl-1999-2006.html
This is a nice TQ/HP bump over stock but still plays nice with everything. Stock springs etc....

It's a 450/450 lift
Stock on a 2002 is
408/414

The above comp cam is about the max you can do and still retain the stock components whilst playing nice.

Good luck

Thank you that's exactly what I was looking for. Do you run it or know anyone who does? I read about that cam being good to go with stock tune and I just wanted to see if anyone had any experience. Definitely Replacing lifters...only parts that I am not replacing are crank, valve spring retainers/keepers, rockers, and connecting rods. Everything else will be new

 

[robo512]

I would call Russ Pottenger at Bishop-Buehl Racing Engines about a cam. He builds a lot of 4.0 engines and could help you with compression ratio with his drop in cam. Stock 4.0s low compression and the piston to low in the cylinder. Both cost efficiency. I'm guessing you want to run 87 oct gas and he will probably ask.

Russ Pottenger
Bishop-Buehl Racing Engines
Work (626) 967-1000
Cell (626) 673-2203
Email/PayPal: [email protected]

Thank you, I sent him an email

 

[Rubicon88]

Thank you that's exactly what I was looking for. Do you run it or know anyone who does? I read about that cam being good to go with stock tune and I just wanted to see if anyone had any experience. Definitely Replacing lifters...only parts that I am not replacing are crank, valve spring retainers/keepers, rockers, and connecting rods. Everything else will be new

Yes and yes.

Definitely a change you can feel.

What's odd to me is all these mfg"s making cams made either a very similar stock cam like OEM...or...they made an extreme cam for a 4.7,4.9,5.0 stoker etc.

That comp cams will serve you well.

 

[Ephry73]

How about stock cam grind and higher ratio rockers?

 

[Brianj5600]

Yes and yes.

Definitely a change you can feel.

What's odd to me is all these mfg"s making cams made either a very similar stock cam like OEM...or...they made an extreme cam for a 4.7,4.9,5.0 stoker etc.

That comp cams will serve you well.

What is the compression ratio?

 

[Rubicon88]

What is the compression ratio?

Of what?

 

[Brianj5600]

How about stock cam grind and higher ratio rockers?

It wouldn't make as much power. You would gain some lift, but almost no duration.

 

[Ephry73]

It wouldn't make as much power. You would gain some lift, but almost no duration.

For sure.

 

[robo512]

It wouldn't make as much power. You would gain some lift, but almost no duration.

That is what I thought. The compression ratio is not given by comp cams. The stock compression ratio is 8.8:1. I called Comp Cams and they said that the cam is safe to run with all stock components and stock tune.

 

[Wildman]

That is what I thought. The compression ratio is not given by comp cams. The stock compression ratio is 8.8:1. I called Comp Cams and they said that the cam is safe to run with all stock components and stock tune.

Some may not agree but if you are going thru all this while doing your rebuild I'd look into getting a tune for it also. Even on a stock engine Chris has said he noticed better performance & drivability. Just a thought.

 

[robo512]

Some may not agree but if you are going thru all this while doing your rebuild I'd look into getting a tune for it also. Even on a stock engine Chris has said he noticed better performance & drivability. Just a thought.

I'm sure some more power can definitely be squeezed out of it with a tune on 93. Some friends and I might go in on an HP tuner at some point in the future so I may try to find a downloadable tune that I can upload myself, or even learn to make my own tune. I was happy with the performance of my jeep before but I am a little weary about performance because I am in the process of upgrading from 33's with 4.10's, stock bumpers, stock fenders to 35's with 4.88's, super dana 35 with eaton e-locker, tube fenders, and heavy aftermarket bumpers so the jeep will be a decent amount heavier.

 

[Wildman]

I'm sure some more power can definitely be squeezed out of it with a tune on 93. Some friends and I might go in on an HP tuner at some point in the future so I may try to find a downloadable tune that I can upload myself, or even learn to make my own tune. I was happy with the performance of my jeep before but I am a little weary about performance because I am in the process of upgrading from 33's with 4.10's, stock bumpers, stock fenders to 35's with 4.88's, super dana 35 with eaton e-locker, tube fenders, and heavy aftermarket bumpers so the jeep will be a decent amount heavier.

Well places like Flyin Ryan Performance or HemiFever offer canned tunes plus you can get different tunes for using different octane.
It isn't always about squeezing that last 2-3 HP at wide open throttle. It's more about that range you drive in that you can get some improvements.

From some of the articles I've read the cams used in Jeep & Dodge engines are always on the lower end of performance. So replacing it is a good idea. Adding a tune on top of that is just icing on your cake. Heck no it ain't gunna outperform a Eco Boost truck or some tuner Honda but that isn't the point.

Since you are going to regear why are you only going to 4.88 gears and not 5.13 gears?

 

[L J]

I am a little weary about performance because I am in the process of upgrading from 33's with 4.10's, stock bumpers, stock fenders to 35's with 4.88's, super dana 35 with eaton e-locker, tube fenders, and heavy aftermarket bumpers so the jeep will be a decent amount heavier.

Rethink the process > 5.13s and aluminum bumpers.