Topic: Hesco Hi - Po camshaft info

[Beachbum]

I haven't installed the cam yet, the last time I was home on my days off it didn't sit still longer enough!!! I was also trying to decide whether to have the head freshened up and valve springs installed. I finally decided to go for it and got another head, it is currently in the machine shop being redone, valve springs, milled and valve job. I intend to get eveything installed when I go on my days off next time, the parts are piling up fast and my wife isn't going to let me get anymore until I get what I have installed. So far I have the following to be installed, cam, head, e fan, Bestop soft top with doors, all new seats, light bar. I did install a 4.0 TBS, hi output alternator and Accel coil last time I was off.

[sharpxmen]

I am interested to hear the result - currently my lifters are extremely noisy (which i understand is a common issue with the AMC 2.5) and i'd be interested to buy the cam & lifters as it seems to be priced fairly. I'll wait for your feedback before i do (i have a other things in the works in the meantime anyway). Thanks for the update and good luck with your setup. Keep us posted...

[Guardian7]

Sounds like Beachbum is doing it right! and I dont see why .03 more compression on the lifter matters since we have self adjusting hydraulic lifters which pump up with oil to adjust up or bleed down to adjust down, there is about a half inch of adjustment within most lifters so as your valve train get worn they keep taking up the slack, this is in fact the only rocker adjustment if the engine does not have adjutible rocker arms! The main thing is to replace cam and lifters with good matched high quality stuff so you dont end up doing the job twice. I also hear there is a special tool for removing the Jeep lifters without having to pull the head.

[Guardian7]

I have built plenty of engines and the hesco guy is right, it's good to change to a stronger timing chain and gear set if the cam has more lift it is going to compress the springs further which creates more resistance to the cam rotation. Changing the springs will allow a higher red line before the valves start to float but Jeep engines are better suited for lower RPM and more torque. Just install the new cam, lifters and timing set using a good prelube and stick with the 0 setting on your lower gear, trust me I have tried the + and - settings and you end up with a dead spot at the top or bottom of the power band that really sucks.

[Beachbum]

Guardian7, I really appreciate your comments and input, although you've got me thinking now (I'm dangerous when I think, ha) Hesco recommended installing the cam in the advanced position, I realize that by advacing and retarding the cam all you are doing is moving the powerband either up or down on the RPM scale. They said in the advanced position I'll have a good smooth idle with strong vacuum. They also said it will pull strong from off idle to 5000 RPM. If you have experience with this particular cam installed in all three positions, I would appreciate all the info you can provide.

[Guardian7]

I have more experience building V8 engines, performance timing sets usually come with 4 degree + or _ on the lower gear. I have built some some fast Datsun/Nissan Z engines also but did not mess with valve timings. With DOHC you can run 2 different cams and really have fun! My tests with the advanced settings usually put the powerband center someplace around 2000 Rpm and by 4000 there was nothing left. This is good for off-road rock climbing stuff but on the road really blows. Try the advanced position but remember its a lot of work to change back if your not happy. Its also good to first find out what the cam will do for your power in the zero position for comparison before trying the other positions. More lift and more duation will give you power throughout the powerband because you get more fuel and air into each cylinder. I think a 1 or 2 degree advance would be nice if you could find it, do you know what the hesco timing set offers?

[Beachbum]

Hey I really appreciate your input. I'm going to go ahead and follow Hesco's advice and install the cam in the advanced position, they are the manufacturer and very reputable. They are  also the comp. that is preparing my head. My Jeep still has 4:10 gears with 33" tires so I can definetly use extra low end power provided by the milled head ( 57cc's) and advanced cam. 4:88 gears are difintely on the horizon but probably won't happen until winter. Most of my wheeling is playing in the sand on the beach and going back and forth to my favorite fishing spots,  I really need lowend power more than top end, it never sees hiway use and very little city use. After I get the 4:88's installed if I need a little more power towards the top end I can always change it back to the 0 position. I will post the results of this install when I get it done, it will be sometime in late June.

Beachbum says: Keep your wheels a spinnin and your girlfriends grinin!!!!

[BK2LIFE]

i ordered the 274 cam, also with the timing set.  i have the closed combustion chamber head.  milled head and block .010 each for a total of .020 thousands( looking for close to 10:1 compression).  replaced valve springs, and shimmed the rockers for a back to stock "preload" on the lifters.  the head has been pocket and bowl ported, and port matched to the intake manifold.  the intake manifold runners have been ported, and on the throttle body side the hole has been opened up to the spacer and the new "bored" out 4.0 throttle body.  looks like i have found out that early full roller rockers from a v8 dodge will work, but have not tested it yet. ( will let you know)
i will post the link to my pics as soon as the parts come from the machine shop.  this motor should make good power, im using the stock injectors as they flow more than enough for a "small" motor. 4.0 injectors will work, but their wide open flow rates are way to much for a 2.5 "4x4 torque) motor.
lastly, to asnwer the above question, when under WOT the computer is pre set and uses the temp sensor and map sensor, for fuel delivery
-james

[BK2LIFE]

oh yeah thats my jeep behind jack here in honolulu
http://www.4bangerjp.com/forums/index.php?sid=ebd204b809b7c4e9b6d3447c4a11a5d7

[Beachbum]

Sounds like your building it right, I'm really pumped up about getting mine put together. I've got a lot of parts to install, it's just hard to park the jeep long enough to work on it and the wife is  bitc - er complaing about parts piled up in the living room, so I'll get it all done when I get home. Good luck with your installation and hope it's a screamer !!!!!!

[supryj4]

I have have not got mine installed yet I am going to order the ajustable roller rockers but I need an extra 1/2" of clerance in my valve cover so I would need a spacer or find two of the aluminum valve covers and cut them in half but leave one a 1/2" longer and reweld it together and I just have not found the time to get this issue worked out yet.

[supryj4]

finaly got everything installed over the long weekend I will post my opinon after I get a few miles on it.

[Oilsmoke]

supryj4
You drive it Yet?
Updates boys, Lets hear some reviews. :D

[sharpxmen]

yeah, how is it - are you smoking the tires  :D ?

[supryj4]

Ok I do not have alot of miles on it yet.Its not my daily driver and I have not had a lot of time to play.Let me start with a little info I already had 62 mm tb,spacer,rock-it intake,borla hedder and cat back,random tech cat,MSD ignition,flex a lite electric fan and with all of that from 4000 RPM to rev limt on computer was basicly my tourqe curve.The motor ran strong and sounded completly differant once I hit that 4k RPM.Now with the head work,cam,roller rockers,dobble roller timing set,and fuel pressure regulator it brought the tourqe cuve down to mid to low 2k RPM range all the way up untill the computer cuts it out.It did make a noticable differance but as always I was hoping for more.It did make a differance in the overall sound and smothness of the motor and how it revs up.It is alot more fun to drive around town. I got It up to 55MPH or so but have not hit the highway yet to see if it helps hold the higher speeds or not.I will keep you informed as I learn more.It does have a nice littel lope to it at idel it sounds good.I did notice that the other night when I was out and it was cooler out it semmed to run better could this be from my rock-it intake being mounted just above the valve cover and sucking in to much heat from the motor.Would that make a noticeable differance?Any input would be appriciated.And no I am still not smoken the tires yet I think it will take a supercharger or a 4.7L stroker to get there But my squerls are just a littel bit more angrer now  :D
http://i71.photobucket.com/albums/i160/supryj4/100_2883.jpg
P.S. stock was many years ago so I cant realy compare it to what the differance betwen stock was and it was tbi then not mpi.