Need to choose cam for my 360 now (xe256h)?

[Creepycj5]

Hey Im new here, great forum you guys have built.

I have a 79 360 I am putting in my cj5 for both offroad and street. I have low enough gears to pull through anything (t18a and 4.88s).

I need to choose a cam this week to get moving with this project. However I have searched and read every post on cams and still haven't gotten a cam picked.

Is this really worth all the time I am putting into picking out the perfect one, or should I pick a manufacturer I like and a rpm range that I think will work and be done with it??

I really like the comp xtreme energy 256, which starts power at 1200rpm. However I read jeeps4ever say he does not reccomend this cam at all, that was for a 401, I am wondering if for a 360 the opinion changes?

Would like it to pull hard low and mid, topend would be nice but I would sacrafice it for low and mid. Im not racing this or anything, just a toy for the w/e's.

I would go with some of the bigger cams I read about on here, I just dont want to have a dog on the lowend.

Any advice at all will be appreciated!!

[fuzz401]

look at the 268 cam

[Creepycj5]

Forgot to mention, I am going to be running a factory 4350 4barrel and manifold, tfi ign., factory exh manifolds.

[Creepycj5]

Looking around more, I found another option which sounds great. Erson TQ-20H, 214 in and ex at 0.050" 0.478" in and ex. 111deg. Also says 4deg advance Im taking a guese they want you to adv the cam 4deg?

Good price and the desc. matches what I want.

Any experience with this or other erson cams?

Thanks

[82Waggy]

Check out the 401 build by donwag in the general chat section of this forum. The second page shows a dyno sheet using the XE256H - made over 400ftlbs from 2000 - 4500rpm. Granted that's a 401 but this cam should produce a good torque curve in a 360 as well. Not sure why jeeps4ever would not recommend this cam but I think Comp may actually be discontinuing it.

Another option worth looking seriously at is the Engle 5054H - this is a 260dur with .501lift. This high lift for the duration is possible in an AMC due to the large diameter AMC lifters and should also yield great low end torque with an extended RPM range.

Comp XE256H10, Engle 5054H
Rocker Ratio 1.6, 1.6
ILCA 106, 108
ELCA 114, 116
LSA 110, 112
Intake Duration 256, 260
Exhaust Duration 268, 260
Intake Lift 477, 501
Exhaust Lift 484, 501
Intake Open, ATDC -22, -22
Intake Close, ABDC 54, 58
Exhaust Open, BBDC 68, 66
Exhaust Close, BTDC -20, -14
Overlap 42, 36

[82Waggy]

By the way, what compression are you running?

[Creepycj5]

stock 79 heads and pistons. Im guesing that is 8 or 9:1.

I will take a look at the engle cam.

Not looking to spend to much, just a mild upgrade from stock, dont want it to wild either.

[82Waggy]

In that case look at the Engle 35018H.

This one is intended to help build cylinder pressure in stock compression engines.

[82Waggy]

BTW,

Stock 360 compression is 8.5:1.

[Creepycj5]

Thanks for the replys.

Just like the Engle cam, the Erson also is claiming in build high pressure for lowwer compression engines. Also claiming faster intake ramps. So far this is the cam I am considering most. For what I will be doing with the jeep I can't see myself needing everything I can get out of it (a stock cam would do the job), so I figure something alittle bigger and that works in the rpm range I will be using most will be what I am after. I also dont want major gas consumption, I will be in the woods on trails all day at times.

The cams that look to suit me well, erson hq20, engle 35018, comp xe256, comp 268. Also summit 8600 but I am not risking their quality, I need this to be reliable. Couldn't find anything I liked to much by crane.

I have the comp 268 in a sbc 327, very good cam and well rounded power, decent amount of chop to the idle, I would give it a shot in the 360 but I like to change things up.

Lastly, I hear a lot about running the stock springs and being ok with cams on the milder end like what I will have. However on erson's website they want you to run new springs. I dont want to cheapen out here and drop the ball, but I am trying to keep this within a tight budget, do you feel the springs are honestly needed?

[AMX69PHATTY]

I would say definitely yes, new valve springs are needed.
At least new stock replacement valve springs.

I would say if the cam specs say 4 degrees advanced,
then advance is ground into the cam and the timing chain can be installed strait up.
Although advancing the cam further would increase effective compression, & low end torque.
RollMaster offers a very nice "Red Label" Timing set with 9 Keyways.
The Cloyes True Roller Timing Set has 3 keyways, Strait Up, 4 Adv, & 4 Ret.

[82Waggy]

The Erson TQ20H has 292 degress duration - that is way too much for a stock low compression engine.

Wide/strong torque curve comes from short duration with high lift, such as with the Engle 5052H with 254,489 or the 35018.

Increasing duration without increasing compression simply moves the peak torque point up the RPM curve(approximatley 500RPM per 10 degrees of duration), does not increase peak torque much if at all, shortens the power band, and results in a significant drop in low end output resulting in rather lackluster performance.

If you want strong power from off idle to the maximum practicle RPM for a stock 360 engine then you need to stay below 260 degrees of duration with as much lift as you can get, without exceeding the lifter limitations.

And yes, you will need new valvesprings.

[Creepycj5]

Thankyou again. Its nice not learning the hardway like so many other times!

I have it narrowed down to the Engle 5054 and Comp XE256.

I sent Engle a tech support question for their thoughts about the 5054, and their reccomendation for a cam (and lifters & springs).

I now see how out of spec the Erson is, compared to the Engle and Comp for lowend torque.

I also asked Engle how the idle would be. I like the cammed idle sound, but I don't want it to interfer with offroading. I would like to keep the idle near factory spec RPM so I can do the slow-go trails and also have compression braking.

I will post an update when Engle responds. Thanks

[82Waggy]

That "choppy" idle sound is the result of "overlap", the number of degrees of which both the intake and exhaust valve are open at the top of the exhust stroke, and late closing of the intake valve during the compression stroke that backfeeds the intake charge - both of these things are characteristics of large duration cams with narrow LSA that is typical of a high compression, narrow torque curve, high rpm setup.

A short duration high lift cam will help a low compression engine achieve a strong and wide torque curve - don't rule out the 5052 either.

[Creepycj5]

Engle already got back to me, here is their response:

"Excellent choice! One step larger than stock with lots more lift for power. Idle is good, we will grind it on 112’ You will need #993 single springs which are 1.430 OD and set up at 1.800” spring height, maybe retainers to get the height and new 862H lifters too."

[KJMac]

The Erson TQ20H has 292 degress duration - that is way too much for a stock low compression engine.

Wide/strong torque curve comes from short duration with high lift, such as with the Engle 5052H with 254,489 or the 35018.

Increasing duration without increasing compression simply moves the peak torque point up the RPM curve(approximatley 500RPM per 10 degrees of duration), does not increase peak torque much if at all, shortens the power band, and results in a significant drop in low end output resulting in rather lackluster performance.

If you want strong power from off idle to the maximum practicle RPM for a stock 360 engine then you need to stay below 260 degrees of duration with as much lift as you can get, without exceeding the lifter limitations.

And yes, you will need new valvesprings.\

The erson is only 214 @ .050.

[82Waggy]

The Engle5054H is 214@.050 - 260@.006

The Engle 5052H is 209 @.050. - 254@.006

The Engle 35018H split duration 207,216 @.050 - 248,260@.006

If I was building an 8.5:1 compression 360 today I would choose the 35018H for a tall and wide torque curve.

[fifesjeep]

Another cheap/easy way to increase low end grunt is to change the Rockers and go from the 1.6:1 (Stock) to 1.7:1.... Like I said It's the cheap/easy way and you should have noticable gains... Especially with a stock cam..

This is the 268 cam specs/unless you go the rocker route which I'd say is ideal for what you are looking for..

COMP CAMS 268
Camshaft Specification Table
Part Number 10-202-4
Engine 1966-1979 American Motors Co.
290ci-401ci
8cyl.
Grind Number A 268H-10
Description

--------------------------------------------------------------------------------

Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.456 0.456
Duration At 0.006 Tappet Lift 268 268

--------------------------------------------------------------------------------

Valve Timing At 0.006
Open Close
Intake 28 60
Exhaust 68 20

--------------------------------------------------------------------------------

These Specs Are For The Cam Installed At 106 Intake CL
Intake Exhaust
Duration At 0.05 218 218
Lobe Lift 0.2853 0.2853
Lobe Separation 110

Recommended Valve Springs 940-16
--------------------------------------------------------------------------------

With the 268 cam and If you changed the Rockers to the 1.7:1 (which there are a few companies that have bolt-ons)... You'll have a Gross valve lift of .485 (A gain of .029")... which will help the low end.

A stock AMC cam with stock 1.6:1 rockers has a gross valve lift of .425"... with a lobe lift of .266..... If you were to get a set of bolt on 1.7:1 rockers you can make a stock cam act like a mild cam.. W/1.7:1 rockers and a stock cam the gross valve lift jumps up to .452" Almost that of the 268 cam with 1.6:1 Rockers.. Plus by doing the Rocker mod you save yourself the hassels of taking the engine apart etc.. all you gotta do is pull the valve covers remove some bolts rotate the engine tighten down bolt the covers on etc....

[fifesjeep]

Ouch, i just priced the bolt-ons!!!! And I don't think it's any cheaper... then again I only checked out Harland Sharp... I purchased a set of 1.7:1 Roller Rockers for $150 with the relief cut on the bottom side.. which required machining (I still lucked out, the money saved on the rockers went to the machining part)... I'm sure summit,crane,Scorpion etc should have some.. Just look for Pedestal mount Rockers 1.7:1.. But the Comp Cam 268 Cam and Lifter set is $264.21 (And if you call there CAM HELP @ 1-800-999-0853 you'll get 10% off)... Even then you will have to buy the gaskets etc etc and after all said and done total amount of money spent for the new cam/lifters springs... etc will be that or less of the money spent on rockers... Plus doing the Rocker up-grade you'll save on down time....

[Creepycj5]

Thanks for the info.

But I got a cam and lifters last week. I went with a crane truck power cam, idle to 4800rpm. I spent $180 shipped. I also got a cloyes roller timing chain and gears, and a hi-flow waterpump. Also a full engine gasket kit, I had some bad valve stem seals etc. I don't expect too much out of the cam, I mainly want a reliable and good running engine.

I was under the impression stock cams had 0.456 lift, I read this somewhere on here.

Also according to crane's valve spring info, they said I need atleast 0.060" more spring travel then the cam's lift. I measured the installed height and fully compressed height, and I'm over double the 0.060" requirement for my exhuast lift of 0.484". So I am going to give them a try, I still have to measure all of them to make sure they are within spec of each other, but this engine has relatively low miles and everything looks good.

[fifesjeep]

Stock AMC 304/360 Lobe lift is .266.. multiply that by the rocker ratio... 1.6:1 (Stock) .266 x 1.6 = A Stock Gross valve lift of .4256".
Stock lobe lift multiply 1.7 (After market) = a gross valve lift of .4522".

[Creepycj5]

Ok cool, I just found the cam specs for a 304 in my clifton book as well. The cam I picked should add alittle more then I had originally imagined.

at 0.050" 204in 216ex
advertised 260in 272ex
0.456"in 0.484"ex
112deg.

Im curious, do they make 1.65 rockers?? I only see 1.6s and 1.7s.