4.6L Modified "Low buck" stroker

[gradon]

And another stroker is born!

[lafrad]

I would think that the Voodoo can would be a bit on the noisy side as it has the more aggressive ramp rates like the CompCam Xtreme cams do. Its interesting that it isn't though.

I have to make a correction... The VooDoo was substituted with a Crower cam. The reason for that was purely a financial one.

[lafrad]

Just got back from a 1200 mile round trip from one end of the great lakes, to the other... happy to say the jeep did well on cruise on the hiway, anywhere between 65 and 75 mph... 19.5 mpg average

It is still stock tires and stock gears (2200 rpm @ 68 mph... )

used about 1/4 quart of oil, which is WAY less than on the stock 4.0L... expecting that to go down as the rings finish settling in... idle has settled into a rock solid 650 rpm (-ish... looks about 100 lower than 750 on the gauge). Valvetrain is still SILENT. Still have a slight header gasket leak. Idle oil pressure is ~25psi, 2200 rpm is 45-ish psi, (high volume pump with main bearing modifications for flow)

2500 miles total on it and I'm HAPPY!

[lafrad]

Still on stock injectors, but feeling a bit more comfortable screwing around...

Standing start (from a stop sign) gives me 2 gears of rubber... about 50' of travel... with... limited traction... no brake assist. Through first gear, well into second before hooking up.

Open Diff so sometimes its a peg-leg... that will get resolved this summer

[lafrad]

Still running strong. I'll have to check the miles next time I'm in the car. Just pulled a trailer for a quick 50 mile trip, engine had no problem and things REALLY drove well compared to before.

[lafrad]

Another update.


31's and a 4.5" long arm lift install make the XJ a very nice machine to drive. It got BETTER on the freeway, and somehow the big tires really adjusted the MPGs in the POSITIVE direction (in a SERIOUS way). Around town its just a touch doggy, but I'm getting used to it.... maybe I'll go to 3.73's or 4.11's instead of the 4.56's that I was thinking about when the funds arrive for proper gearing...

The valvetrain is settling in. its not quite a "silent" on higher milage oil (3000+ miles) as it is on fresh oil. I guess that will be my indicator of when to change it from now on.

I'm very happy with the motor! everything is running just as it should!

[SilverXJ]

You went from stock to a 4.5" lift and 31s and got better highway mileage? Did you correct the speedo gear for the increased tire size?

[lafrad]

I did not correct the speedo. The results when using the miles per gallon using the trip counter (divide at the gas station) came out to be 19.5xxxxx mpg. I did travel with family, and the trip counter in my parents new vehicle (and google maps measurements) all showed it to be getting about 21-ish mpg. This is supported by the fact that the new tires are 10% bigger in diameter than stock... so the trip meter showed 10% too few miles...

[Busey]

I am thinking about using the same Crower cam and was wondering if you were still having good luck with it.
were you able to use stock valve springs & rockers ?
Thanks

[lafrad]

Jeep is running great! Driving it daily and it has no complaints. No stalls, smooth idle, nice torque. I never hit redline really, I have a Hemi for that so this cam works GREAT for my needs.

Still on stock injectors and have not installed any MAP sensor tricks or anything.

I Installed aftermarket valvesprings. I started a thread on that \... showed what i did. I don't think there is enough room on the stock stuff for the crower cam.

[SilverXJ]

Easy on the WOT if you are running stock injectors. Just because it doesn't ping doesn't mean its not lean. Unless you can watch the AFR with a wide band or at least a narrow band.

[lafrad]

Oh I know. I tune the hemi's I drive, widebands, etc etc etc. WOT in the Jeep is not really even in my thoughts yet.


I'm REALLY Hoping to get an SCT tuner here and be able to fully tune it. we'll see

[Busey]

did use an off the shelf cam in your 99' ?
I emailed Crower yesterday and this is their reply
"1964-1997 4.0- regrind only for you 98'. it has a flange on the nose"
I thought only 2000' and later were different

[lafrad]

Yep, I used their off the shelf cam, and had to get the cam bolt with pin to put in the front... (no more cam retainer plate).

If you are able to do a Factory regrind, however, I would REALLY consider it. if you have a cam that hasn't worn the tops off the lobes (the WIDE lobe variety), Crower is VERY good at regrinding and re-prepping cams for use in the vehicle. You could easily get a "good condition" stock cam ground to whatever custom specs you want, and have all the benefits of wide lobes and a retainer plate.

the '99 XJ is a weird year. it has the "new" intake from the factory, but still a distributor and plug wires. It has the new cam retaining plate, but the timing cover has the button cast into it for the Cam retaining pin.

[Busey]

my engine has the bolt with spring & plunger pin. It is out of a 1998 Cherokee but has a late 1997 casting date on the block.