double_ot_xj

Im thinking of putting a nw cam in my 4.0 to give it more torque. i had a buddy with a 82 rabbit and dropped 1.5 seconds on the strip after a cam change. has anyone done this mod? are there any writeups on this? whats your opinion, do you think its worth it. your info, feedback , and opinions are apprecited.

double_ot_xj

ok, i did some research and i found this at Crane Cams. I think its what im looking for. http://www.cranecams.com/pdf/Page159.pdf
i found it online at http://www.partsamerica.com/productd...tNumber=753905 for $135

98 JeepJeep

I think a cam swap in a 4.0 would be awesome because the highest RPM'S mine goes at WOT is 3.5K. Remeber to change the lifter too.

SeriousOffroad

A few thoughts from a guy that’s built a stroker and had a cam failure after 20k miles.

Even though I followed all of the written instructions, performed the break-procedure perfectly, used the right oil, my Crane Cam still lost a lobe.

Do your homework and read everything you can find on proper lubricants, cam and lifter installation, and lifter preload. I’ll add some links for ya at the bottom of this post.

Replacing a cam is never as easy as just stuffing a new bump stick into the block. If you’ve got a high mileage motor, the right way to do it is to install new cam bearings in the block. For most of us this means pulling the motor and taking it to a machine shop. If you’re going to go that route you might as well install new rod and main bearings too.

The gains advertised by cam manufacturers should be taken with a grain of salt…a very large one at that. While dramatic on paper, most of us will never see those kind of gains at the rear wheel. Why? Good question. A stock XJ weighs in at around 3000 lbs., but who is going to leave it stock? Start adding armor, bigger tires/wheels, winch, lift kits, etc, etc, etc…and all of a sudden your once lean and mean heep is a porker. A 15% gain in torque at the rear wheels is hardly noticeable.

Am I trying to talk anyone out of a new cam? Well yes and no.

Yes if you are of the mindset that a new cam will allow you send white smoke billowing from the wheel wells as you take off from a red light in search of Corvettes to race.

No if you honestly weigh the amount of work involved and realize that a bigger cam may only help to get a little more power to the rear wheels to compensate for the add-on’s you already have.

So now that I've rained on everyone's parade, a few links for you read through. Bookmark 'em and refer back to them often.

Flat-Tappet Cam Tech

Lifter Preload

Cam Failure

My Cam Failure

Jsny1010

If your just swapping the cam its not worth it... since your under there might as well as do an overhaul all the seals etc....the 4.0 already has enough power.. are you trying to race it??

76ANTHONY

i take it before the cam swap you already did a header and exhaust, correct? this adds a little hp and tq if done correct. at least thats what i hear

TrekkerJmm

Does any company make roller cams and roller rockers for the 4.0? I did a search but came up blank...Tj

SeriousOffroad

Yes, but but be prepared to spend $600-800 for a custom ground cam from a cam blank.
There's a thread on it over at www.jeepstrokers.com

TrekkerJmm

EEE OUCH thats alot. Thanks Frank...Tj

double_ot_xj

like i said i was thinking of...not leaning tword. the thing is that i have no real experience in this area and was taping the wealth of knowlage i call this forum. i appreciate your past histories. i figure if you dont learn from history your doomed to repeat it. looking at the pro's and con's list i dont think it is a viable option at this juncture, but again, i do greatly appreciate everyones input.

double_ot_xj

speaking of intake and exhaust mods. i have settled on an ARB Safari Snorkel and a flowmaster 40 muffler wit either 2.5" or 3.0" tubes. i just cant find heads to save my life. i have found a $h!t ton that will fit the 4.0 i have but there all for the Wrangler. will they fit my rig or am i going to have something custom built? please dont tell me the custom build(crossing fingers).