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Thread: LSA Camshafts

  1. #71
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    Quote Originally Posted by GTS2017 View Post
    “The more you know, the more you know you don't know.”
    Ain't that the truth.

    There are some good articles on trials that superchevy did a few years back using both NA & FI spec cams in FI applications. I'm sure they can be easily found on the net. In summary the all "work" it just depends on what you want.
    I think badass or someone like that also did the same & guess what, same results.

    The cam in my VF GTS is more of a NA cam (I wanted street not race car) and I'm happy with it & how the car drives & performs. Can't tell you any more about the cam. My tuner did a fair bit of development with this (and other) cams in FI.

    If big numbers are your thing, go more of a FI spec cam as big as you can / want, allowing for other mods and how it will drive.
    If numbers aren't your priority then you have heaps to choose from and from my experience anyway, it can get confusing. Go with what your tuner is familiar with and as others have correctly stated, what he can tune "properly".

  2. #72
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    biggest factor is engine/exhaust/intake combo that will vastly change any cam u purchase, dont worry too much about lower overlap for boosted just stay 114 or above and it will work u dont suddenly loose boost from overlap i have 57 deg overlap and with my old exhaust peak torque was at 3800rpm and my cam is ment for 3000-6800+ boost changes everything, if u want better manners down low then less overlap (more vacuum) can help but thats also up to the tuner and if they bother to tune below 2500rpm.
    i can admit i picked the wrong cam as my first ever choice but after getting use to it and tuning the bottom end load areas properly its good now but if or when i do change cam it will be very different to what i have now, i even get around 8L/100 with petrol on highway with current cam so tuning is everything, only thing i can recommend is try to pic a cam for what u want to do if u want daylie use, or weekender or track, or if u want a track but also daylie then there has to be a compromise and a good tuner can allow a bigger cam to still behave down low, its been said alot but a tuner can make a cam the best thing ever or your worst nightmare

  3. #73
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    Quote Originally Posted by alterego78 View Post
    The list of mods in Genf gts's stage 3 that run 10's is sort of a hint. Cam plus pushrods, lifters, dual valve springs, retainers, rocker upgrade, valve stem seals, collets. Is that similar to the cams you are comparing?

    Sent from my SM-G900I using Tapatalk
    A must when doin mods , Oil pump

  4. #74
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    Quote Originally Posted by 07GTS View Post
    biggest factor is engine/exhaust/intake combo that will vastly change any cam u purchase, dont worry too much about lower overlap for boosted just stay 114 or above and it will work u dont suddenly loose boost from overlap i have 57 deg overlap and with my old exhaust peak torque was at 3800rpm and my cam is ment for 3000-6800+ boost changes everything, if u want better manners down low then less overlap (more vacuum) can help but thats also up to the tuner and if they bother to tune below 2500rpm.
    i can admit i picked the wrong cam as my first ever choice but after getting use to it and tuning the bottom end load areas properly its good now but if or when i do change cam it will be very different to what i have now, i even get around 8L/100 with petrol on highway with current cam so tuning is everything, only thing i can recommend is try to pic a cam for what u want to do if u want daylie use, or weekender or track, or if u want a track but also daylie then there has to be a compromise and a good tuner can allow a bigger cam to still behave down low, its been said alot but a tuner can make a cam the best thing ever or your worst nightmare
    Hooray .... I knew in the end 07GTS or LSTuner would make a considered post on this thread that can be real use to the OP ... well done 07GTS ... as per most of your posts, you are the one to make "common sense" of things!

    The OP has choices based on what his driving objectives are ... Street or Track .... sure a SC combo can make good torque and excellent power ... but what do you really want? .... there are plenty of guys on this forum that will NEVER run their car down the quarter but they want other preferences .... good street presence with an aggressive amount of cylinder pressure to create a sharp idle and massive torque from 2300 to 5000RPM ... and then there is the smaller group that want angriness and power all the way to 7000 that will give that low 10sec quarter ....

    I feel you have enough data from this thread to make your next round of decisions....read 07GTS's post carefully .... he passes on good advice based on real world experience .

    Make sure your selection leaves you with the right amount of Vacuum ...
    When you choose your shop to complete your combo make sure you understand Cam timing .... and what it can do to improve your combo when it's correct ... and ask the Tuner if he can check and dial the cam into where you want it ... if he gives you a blank or dumb look ... run ...

  5. #75
    Quote Originally Posted by 1QIKLSA View Post
    That's just what you need to run a large-ish cam. You would want to change all those things but it doesn't say anything about the specification of the camshaft
    Your original post queried why walky and harrop cams dont run the times the FII cam does.

    I dont think either come close to that list. The harrop stage 5 and Walky 557 from memory each left some off? Im no cam guru, but if thats the case its not a coincidence.

    Maybe the FFI cam opens faster and further. More stress, but more power?. The cam specs dont really matter, the other 2 are just cost cutting.

    Sent from my SM-G900I using Tapatalk

  6. #76
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    Quote Originally Posted by alterego78 View Post
    Your original post queried why walky and harrop cams dont run the times the FII cam does.

    I dont think either come close to that list. The harrop stage 5 and Walky 557 from memory each left some off? Im no cam guru, but if thats the case its not a coincidence.

    Maybe the FFI cam opens faster and further. More stress, but more power?. The cam specs dont really matter, the other 2 are just cost cutting.

    Sent from my SM-G900I using Tapatalk
    While you're correct in saying the others are "cost cutting", my understanding is you can still get away with standard lifters and rockers but it's good insurance to change them to handle the harsher load. Same with the oil pump as mentioned.
    I would beg to argue that the cam specs don't matter as I think they are a bigger factor than the supporting parts.


    Found this video to be pretty informative


  7. #77
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    Quote Originally Posted by 1QIKLSA View Post
    Found this video to be pretty informative
    These vids are always a good thing for basics but your after better data ... they failed to give AFR's or Exhaust temps etc which would affect tuning and possibly create data to help tuning ... so in respospect that was a water vid opportunity

    The only good info was the size of the pipes ..... in a validation sense as in many cases I believe far too many guys fit pipes that are too large and hamper air speed due to turbulence which creates heat as well as poor flow .. and that just another whole topic you need to consider when you finally choose your combo .... again ... I think that Smokey has the best info to help everyone get a good basic level of thinking started!

  8. #78
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    Quote Originally Posted by 1QIKLSA View Post
    While you're correct in saying the others are "cost cutting", my understanding is you can still get away with standard lifters and rockers but it's good insurance to change them to handle the harsher load. Same with the oil pump as mentioned.
    I would beg to argue that the cam specs don't matter as I think they are a bigger factor than the supporting parts.


    Found this video to be pretty informative

    The Oem oil pump is a good bit of gear . The question is why wouldn't replace a used oil pump when you can buy a new on for $150 and have peace of mind. It's the same with the timing chain. At a minimum replace chain with a c5r. There's no labour costs
    To replace
    If you do top end mods and you can't afford to replace those 2 items you shouldn't be doing mods at all

  9. #79
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    Quote Originally Posted by Sniper View Post
    These vids are always a good thing for basics but your after better data ... they failed to give AFR's or Exhaust temps etc which would affect tuning and possibly create data to help tuning ... so in respospect that was a water vid opportunity

    The only good info was the size of the pipes ..... in a validation sense as in many cases I believe far too many guys fit pipes that are too large and hamper air speed due to turbulence which creates heat as well as poor flow .. and that just another whole topic you need to consider when you finally choose your combo .... again ... I think that Smokey has the best info to help everyone get a good basic level of thinking started!
    It was more an understanding of what the cam specs mean. What they do and how to interpret them, not about how to tune it.

    Is this the book you mean? Nothing against Smokey but the humble air pump has come a long way over time and I'm pretty confident Smokey wasn't forcing 12-18PSI of air down its neck via a modern age supercharger back in the day eithercid_135.jpg

  10. #80
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    Yep .... that's the book ... it will help you understand valve train harmonics which is critical to a cam installation of any sort ... sure he was in another era but those good engine builders and tuners will all have to applied many of Smokeys tips to achieve perfection

    From my very first post on this thread I was suggesting you understand your entire valvetrain and my thoughts have not changed ... "there is no substitute to a good smooth valvetrain " ... whether it's N/A or Charged ... your valvetrain still has to pump the air in and out ... boost of any persuasion won't substitute that ... which is why I encourage you to read Smokey ... sure it's old ... but it's relevant ....

    if your running a "Hydraulic" valvetrain - which 99% of ppl on here are ... you have so many things to get right ... Cam, lifters, pushrods (both in length and thickness) , rocker geometry, valve springs, rocker stud movement (which is why there were "Stud Girdles" on that engine in your vid this morning) .. and that's all before we get to valves .... so you can take a cheap swipe at me about my "air pump" description but it's relevant ...

    Again, I say ... all the guidance you need is on this thread .... and after you've got your head around that you will be better informed to how you choose your Cam ...







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