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  1. #16
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    If you use the right break in procedure , buy top notch lifters and use the comp cams additive every time you change oil - you wont wipe a lobe.
    Break in is vital , lube everything with the red lube gloop they supply you when assmebling. Make sure the engine fires at the first try or so and rev up immediately to 2500 and vary the rpm from 2-4000 rpm over the next 15 minutes . I use diesel engine oil (rotella) in my motors these days. I have never lost a cam when I have used the comp cams additve and this break in routine.
    As an aside , one day at drags I saw a real shadetree mechanic doing a trackside cam change , he was grinding the convex tops of his lifters flat by rubbing em on concrete as he was exclaiming "these damn yanks , cant they make a proper lifter" , needless to say , the car spluttered and farted down the track which just went to reinforce his idea that the "yank" cam was rubbish.

  2. #17
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    Quote Originally Posted by Rodney Gold View Post
    If you use the right break in procedure , buy top notch lifters and use the comp cams additive every time you change oil - you wont wipe a lobe.
    Break in is vital , lube everything with the red lube gloop they supply you when assmebling. Make sure the engine fires at the first try or so and rev up immediately to 2500 and vary the rpm from 2-4000 rpm over the next 15 minutes . I use diesel engine oil (rotella) in my motors these days. I have never lost a cam when I have used the comp cams additve and this break in routine.
    As an aside , one day at drags I saw a real shadetree mechanic doing a trackside cam change , he was grinding the convex tops of his lifters flat by rubbing em on concrete as he was exclaiming "these damn yanks , cant they make a proper lifter" , needless to say , the car spluttered and farted down the track which just went to reinforce his idea that the "yank" cam was rubbish.
    to be fair, i installed an XE256H in my old mustang, used rotella with comp cams break in lube. i installed the spring and lfiter kit that came with the cam, fired to 2500 for 20 mins (open headers good times)

    and it is running great 3 years later. if i wouldnt have read here about the xe lines wiping lobes i would have never even thought about it.

  3. #18
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    I would go with a hydraulic roller, that way u don't ever have to worry about breaking it. The lifters get a little expensive, but sometimes there are good deals to be had on ebay. I have seen hydraulic roller kits go for around $500 at times. The lifters u need have the link bar connecting them together. You will also need a strong timing cover which will hold a cam button. The cam button prevents the cam from moving in and out of the block. It has to be set just right, comp cams makes a cover designed for this, but it ain't cheap. If u do decide to go with a roller, make sure to change your valve springs out too. It's a chore with the heads already on the engine.

  4. #19
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    ok gonna bring this thread back since id really want to hear from actual users of any of these cams in a BB


    of the three i am looking at
    the xe268h
    the high energy 268h
    and the magnum 270h

    does anyone have one of these cams in there basically stock 454.
    my main goal is low end improvement.
    the only real mods are headers and 2500 stall

  5. #20
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    I use the 268h in a 454 , its in an El Camino - not the USA one , the aussie one , basically a Holden ute - it weighs in at about 1560kgs
    I had a much more radical cam in it , a 280+.
    Heres the rub - I took the rear end from a 3.75 :1 to a 3:1 , Took off the airgap manifold and the 800cfm Edelbrock and used the stock manifold and a 750holley and installed the milder cam , stock rect port heads and stock comp ratio .. I went from a 12.7 to a 12.75 with the detuning and found the car a lot better to drive on the street.
    The cam swap , with a stock th400 , did NOT give me the bottom end huge boost in grunt that I expected , it was better at low rpm but not a night and day difference. The vehicle has very little traction as is , i use 295/50/15's out back but it has a leaf spring suspension (I use a ford 9") and this "worsened" to the point the vehicle cannot be used when the roads are wet and turning a sharp corner in 1st or 2nd doesnt need much to provoke a 360 or "unassisted" turning.
    You have a high stall and high rear gears - the extra torque of the lesser cam will make your stall higher...but the high gearing and limited revving of the milder cam will limit your top end.
    Assuming you using a 235/50/15 out back , your gearing will be 32 k/per 1000 (20m/per 1000) and your top end would be 186 k's or round 115mph at lets say 5700
    You might want , with this setup , a cam that can rev to 6500 or so and to limit your bottom end , cos the stall will "take up slack" so to speak ?

    Any cam you listed will "work" with what you got , even something more radical will , unless you match up a more radical cam with a low comp engine , and you arent sure of what your comp ratio is , so assume its under 10:1....
    So my advice right now is to select a cam that works with a 9.5:1 comp engine , I cant see any of your listed cams being hugely superior to each other....
    My take on your situation would be to up comp ratio to 10:1 and then use a radical cam as you seem to have the rest of the equipment to utilise it.......I'm not quite sure why you want bottom end with those rear gears and the stall...?

  6. #21
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    i just dont want it to be a dog off the line.

    i was originally looking at the xe274h which requires the 2500 stall and the headers but it was suggested that i might lose so much bottom that i wont like the take off.

    the CR is definitely under 10
    its more like 8.8

  7. #22
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    As I said , any of those cams would work well , a 454 produces a lot of torque and I cant see any of em reducing bottom end , with repect to any other , but more than 10lb/ft or so and I cant see any of em having some wierd and wonderful peaky torque curve. Im not sure if the Xe274 requires a high Cr to work properly , but it will most likely allow higher rpm which would increase your "embarrasingly" low top end. (my 1.5l VTEC Jazz/fit with a cvt can beat you on top end , but would take about 10x longer to get there)
    Losing bottom end in a 454 , especially with your setup , is not really a bad thing , I cannot imagine that you can get traction if you flash the motor to 2500 on the line? If you arent violently spinning the tyres when doing that , especially with a 3.5 rear end , then there is something drastically wrong with the motor...........
    PS don't launch by trying to hold the motor at its stall against the brakes , you will wind up the suspension etc..the way to use a 2500 stall to launch , if you dont have a transbrake , is to mash the pedal from idle....

  8. #23
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    from a dead when i stomp the pedal now, the wheels start spinning and the entire car shifts left until it catches second and then will straighten up
    i just want to make sure i dont lose that by shifting the power band too high.

    using camquest it says that the #1 cam for my engine is the xe256h

    346hp at 4000hp and 511ft/lbs at 2500rpms
    thats right at my stall speed

    the xe268h rates at
    370hp at 4500 and 491ft/lbs at 2500

    the xe274 projects
    375hp at 4500
    and 477ft/lbs at 2500

    no one has ever suggested the xe256h for a 454.
    so would it be better to sacrifice 20 or so ft/lbs of torque on the low end to gain 20 or so hp on the upper end.

    in my uneducated perspective i think that the torque to get the car moving would be more needed than the high end getting close to redline increase in hp.

  9. #24
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    The stall is there to bring the car to the powerband more quickly than stock, You need RPM to get a decent top end , a cam that ends at 5000 rpm is wasting the other stuff you got on the car...the 20lbs loss will actually be beneficial as you might spin a little less and get way more traction and thus get a far quicker pullaway.
    Go for the 268...you wont be sorry.

  10. #25
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    Quote Originally Posted by Rodney Gold View Post
    Go for the 268...you wont be sorry.
    the xtreme energy 268 or the high energy 268

  11. #26
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    Keep in mind that DC is more important than CR. CR is a good impression on what you have but if your CR is only 8.8 and you get a to big cam then the real compression DR will drop to (just an example) 6:1 or less. I don't know what is a minimum DR for a engine to operate the right way but I think its usefull to find out. Good luck

    Groeten Peter

  12. #27
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    thats my only worry. i dont want to go too big. id rather get a cam that might be one size too small than be too big.

    comp ratio is the main thing i am worried about. stock 72 454 comp ratio is 8.5:1 with 113cc chambers

    i have heads from a 66 L36 427 which supposedly are 98.4cc. i found specs that said that the L36 was 11:1

    so if nothing else changes and you drop the combustion chamber 15cc per cylinder how does that affect ratio? i would guess it would go up but by how much is the question

  13. #28
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    Go for the High energy 268h...its a fine choice - as I said , I use one in my 454.........

  14. #29
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    Quote Originally Posted by Rodney Gold View Post
    Go for the High energy 268h...its a fine choice - as I said , I use one in my 454.........
    the comp cams simulator puts them really close in performance plus the added benefit of an easier break in.

    what else has been done to your motor to go along with the 268

  15. #30
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    Nothing much really , a set of headers , a decent msd Distibutor and a MSD6al....it has got slightly stiffer double valve springs in from the more radical cam , but stock rect port heads and stock intake...
    I had an airgap and a Edlebrock 800 on prior to cam swap...but as I said before , after fairly radical de tuning to a more driveable condition...it lost all of 0.05 secs on the 1/4 mile
    Heres an ad featuring the car and some pics of the motor (prior to detune with 800cfm carb but stock intake , the wide angle one is after the detune - burnouts on strip pre and in parking lot prior...)
    Chev beast - 454 el Camino - Cape Town used car for sale - Gumtree Cape Town Free Classifieds

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