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    #16
    From a suggestion from MR ltd, i chose the XE258 over the XE264 due to its tq charecteristics. I have done exstensive research on this particular cam. THis cam pulls like a freighttrain from 1500-6000 rpm, everyone i know who has used this cam loves it,mainly they put it in a truck or some sort of 4 wheel drive.
    i found one for 180 bucks new,however in order to run one it is reccomende to change the springs, (I chose beehives) hardened rods,and 1.6 RR.
    It is indeed an HO on steroids! the specs are very much like a HO cam except is has .455 and .544 lift. the intake closes early though,and favors the exhuast side. with E7 heads it will be done around 4500 or so.,hold on got some info. This was sent to me on a EECtuning board when i posted about the XE258.

    I know user name Adam McLaughlin has used it in the past on his V8 Ranger. It was used on a set of ported E7 heads, but the bottom end was a 351w. He seemed to really like it. He couldn't remember what cam was in his engine and he thought he was upgrading by replacing it with a Crane Powermax 2020 (pn 444211), but when he pulled the cam, he found it was that XE258, which is Comp's version of the Crane 2020 with VERY minor differences in lift, duration, and events. So it turned out to not really be an upgrade. He later replaced his E7 heads with AFR185s, which obviously were noticeable upgrades. The high lift of either of those cams somewhat goes lost on stock heads. The biggest benefit to having a high lift cam on stock heads is it holds the valve at a max-flow position for a sustained amount of time. The AFRs really appreciated the lift though since they continue to gain in flow capacity right up to the lifts these cams give. He probably would've done better with AFR165s with a stock F-150 intake and this type cam, but he got talked into the AFR185s purely because the bottom end is 351w and people just default to saying AFR185s work best on 351w bottoms.

    I also know that Ken Collins of BadShoe Productions (www.badshoeproductions.com) uses the Crane 2020 in one of his cars and was VERY impressed with the output.

    I'd recommend either of these cams to anybody looking for extremely high torque in the typical street RPM range (idle-4500 RPM range). They compliment stock or stock ported intakes perfectly and work equally as well with aftermarket street heads like AFR165s, TFS TW 170s, etc. Both peak around 4500 and start to fall off after ~5000RPMs and you pretty much need to be shifting at or before 5500 RPMs which works out GREAT if you are running a stock ported Cobra/Explorer intake since that's about where they fall off as well.

    The downside to either of these cams is that they have such high lift, you WILL need to replace the stock springs, retainers, AND rockers. So figure that into your budget when considering this cam. When upgrading the rockers, do NOT go with 1.7 RRs. These cams both have very fast ramp rates and very high lifts. Going to 1.7RRs will just cause you complications especially with the XE258. If you want a cam that doesn't REQUIRE replacement of stock springs and rockers, then I would point you to RM Competition (www.rmcompetition.com) where Randy Malik sells custom grind cams. He has a series of cams he's developed for a few different applications. The lift is right at the limits of stock springs and rockers. He highly recommends replacing both to reduce the very high likeliness of valve float, but it is not absolutely required. Of his selection of custom grinds, I would recommend his HR256/263. The catch with this cam is to get the most out of it, you need to advance it 4-6°. He designed this cam to work in a Speed Density controlled F-150s with no computer tweaks required. But to get everything this cam can offer in a MAF-based system, you can advance it and get another 3-8hp across the RPM range. When advanced 4°, this cam is VERY similar to the XE258 and 2020 with the exception of the lift which allows it to be more suited for stock components and be, quite literally, a drop-in replacement for any stock cam. You will need to get a timing chain kit that allows you to advance the cam, but the difference in price between a standard chain kit, which you should be buying with a new cam anyway, and one that will allow you to advance the cam is minimal. If you want to look at the specs of this cam, I believe Clint has gotten all of Randy's cams into EEC Analyzer for you to review and compare. If not, respond back and I'll post all the specs into this thread.

    And as for fuel economy, that will have more to do with your ability to stay out of the accelerator pedal. Given you can do that, there should be no loss in fuel economy going with this cam. I don't know for sure if they'll gain you fuel economy over a stock cam since the people that I know that have used these cams also did other mods at the same time and thus comparing fuel economy to their stock fuel economy wasn't comparing just the cam, but I don't believe either if these cams will cost you. I wouldn't be surprised if it improved fuel economy slightly. According to Randy's website, his cams do have a fuel economy improvement which would lead me to believe the other two could as well.

    Moving on...if you are upgrading the stock intake, upgrade to an Explorer upper & lower and if there's room in the budget, send the bottom end off to Tom Moss to have him port it out for you. Or if you are not afraid to port an intake, port it yourself. There are documents in the Tech Docs section written by Tom Moss that talk about how to do this...and how NOT to. Porting only the lower (the weak link in the pair) should gain you a few HP across the RPM range, not just at the top end.

    For others that read this and already have an aftermarket intake, aftermarket heads, and/or a stroker kit and are thinking these cams are just a little too conservative for them, and thus need a cam that can be a good street cam, but extend up into the 6000 RPM range, the higher performance version of the Crane 2020 is the Crane 2030. I don't know that it has a Comp counterpart that is as close as the XE258 and 2020 are to each other, but if I had to guess, I'd say the XE264-HR14 would be your next step up from the XE258. The XE264-HR14 and 2030 are not quite as torquey off-idle, but they are still good street cams and sustain torque higher into the RPM range...but only if the other components can support you that high also. Putting a bigger cam on an engine where the heads and intake can't keep up is more detrimental to the total engine performance than picking a milder cam.

    _________________
    89 townie, mild exhuast up grades, soon to have loud ass stereo....

    Comment


      #17
      so after you deck the block, how far are the pistons in the hole?
      after you resurface the heads, what cc are the chambers?

      you have alot of compromises here, as much as you are sensitive about it, it is what it is; you may not have as much success as someone else if they have other parameters that differ from your combo as a whole

      Comment


        #18
        Originally posted by jayh View Post
        so after you deck the block, how far are the pistons in the hole?
        after you resurface the heads, what cc are the chambers?

        you have alot of compromises here, as much as you are sensitive about it, it is what it is; you may not have as much success as someone else if they have other parameters that differ from your combo as a whole

        That's fine, I just wanted to get some suggestions from the guys here. If it proves to be too much trouble, I'll stick with the stock 'sploder cam.

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