Register now to get rid of these ads!

Technical Big block cam recommendation

Discussion in 'The Hokey Ass Message Board' started by Sporty45, Mar 1, 2020.

  1. DOCTOR SATAN
    Joined: Mar 21, 2014
    Posts: 711

    DOCTOR SATAN
    Member
    from okc

    Isky jet boat grind, endless powerband
     
  2. This is the most I can find
    2.06 1.72 Open chamber 116cc
     
    Sporty45 likes this.
  3. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    Thanks, that's more than I could find! ;)
     
  4. Neb Hillbilly
    Joined: Dec 20, 2019
    Posts: 337

    Neb Hillbilly
    Member

    I have had plenty of luck with peanuts on budget 454s. What pistons do you have? I would likely run a cam in the @ .050 duration of 224 in 235 exhaust on a 110 lsa. Though those heads lay over at 5k or so should still easily make 400hp and 500ftlbs of tq.

    Sent from my S48c using The H.A.M.B. mobile app
     
    Sporty45 likes this.
  5. Neb Hillbilly
    Joined: Dec 20, 2019
    Posts: 337

    Neb Hillbilly
    Member

    Sporty45 likes this.
  6. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    I'm using:
    Speed-Pro Hypereutectic Pistons H693CP.

    22 cc dome, should give me approx 9.2 compression ratio
     
  7. Neb Hillbilly
    Joined: Dec 20, 2019
    Posts: 337

    Neb Hillbilly
    Member

    ok good, most guys have the belief that flat tops get you to 9s. Most of these engines are 7.8-8 stock. They still have big displacement and can handle more cam than the one would think. I would go 265 AFRs if I had money or 781/049s if I was poor and port them like shown on vortecpros YouTube videos.

    Sent from my S48c using The H.A.M.B. mobile app
     
    Sporty45 likes this.
  8. Almostdone
    Joined: Dec 19, 2019
    Posts: 352

    Almostdone
    Member

    I didn’t read every reply, so sorry if this is redundant. It’s been a while since I had a BBC, but it was a real barn burner on the street with a setup similar to yours (except 3600 lbs, 3.31 gear). Lift 0.555 I, 0.565 E, duration 300 I, 310 E. Not a HAMB vehicle, a ‘70 Chevelle 402. Look for something like that in a hydraulic flat tappet and you’ll be happy.
     
    Sporty45 likes this.
  9. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    Yeah, those AFR's look awesome, but are spendy! I just don't have that kind of disposable income unfortunately :(
    I'll build with what I have for now, and I can always upgrade the heads at a later point ;)
     
  10. lippy
    Joined: Sep 27, 2006
    Posts: 5,118

    lippy
    Member
    from Ks

    Gotta be fair. Too new for the HAMB.
     
  11. Neb Hillbilly
    Joined: Dec 20, 2019
    Posts: 337

    Neb Hillbilly
    Member

    Absolutely. I have a couple of big block cars in the garage right now. One is a 427 in a 80 camaro that I took on drag week in 2011. It has Brodix heads and a solid roller with 10 to one compression and on the bottle make right around 1025 based on the RWHP. The car is 1/2 apart waiting on me to finish the front coil over conversion.

    On the complete other side of the spectrum I have a ultra budget 454 I got for free in a 1970 chevelle. I added 228/235 duration erson hyd cam when it was stock with peanut ports and used it in my 74 chevelle sedan. When I pulled it out for the 1970 I inspected the stock short block and it has a significant ring ridge that needs bored. I rubbed "never mind" on it and added small chamber early 396 heads to get the compression to 9.5 to one. Topped it with a GM version of a Performer RPM qjet and a 78 454 Qjet. It really runs good for the junk it is. I am building a dual upper air bleed qjet for it so I can lean out the cruise A/F and it may someday get overhauled but for now I am happy.

    You don't have to spend all the money to have fun and that is what this hobby is about, just get out there. Really a mild BBC make great streeters and even garbage ones make great torque and reasonable hp.

    Remember with a cam change you need to do valve springs and those peanut ports will have rotators under the exhaust springs. Guys will tell you that you need to replace them with spacers, but I have welded or brazed them solid so they become a spacer. I would get 3/8 pushrods & guide plates at the same time (the 5/16s are super small). I usually steal the guideplate off a 366 or some other bbc for free/cheap and buy/find stock 3/8 pushrods . The biggest concern I have about specing your cam is the stall speed. It should still make enough torque but I hate converters that fight you at the stoplight.
     
    Sporty45 likes this.
  12. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    Whatever cam I end up with I will either buy in a kit with lifters, timing chain and sprockets along with new springs, or I will get all that separately. Either way, I'll get new springs! The heads I have now have rotators under both the intake and exhaust. What is wrong with using rotators? I thought that would be a good thing, no?

    I'm using a stock converter with a TH400.
     
  13. 6sally6
    Joined: Feb 16, 2014
    Posts: 1,305

    6sally6
    Member

    you DO realize you can get a custom grind for about the same price as a shelf grind!?
    Take the best 'parts' of the Comp Cam and the VooDoo cam and get a perfect cam. With those tiny runners(peanut) look at a cam with A LOT of lift. Don't go nuts because rockers and springs need to be considered. I like the 110 LSA of the Comp Cam or maybe a 108 LSA if you want more bottom end. Tighter LSA gives better grunt but idle quality(a little snotty) MAY start being a concern. A well tuned carb and the large cubic inch should still allow a decent idle while in gear (in traffic) Even with the tiny heads this thang should still yield more scoot than the factory hot rods of the 60's. Hope you're going with the Quadra jet carb/750 cfm
    6sally6
     
    Last edited: Mar 5, 2020
    Sporty45 likes this.
  14. Neb Hillbilly
    Joined: Dec 20, 2019
    Posts: 337

    Neb Hillbilly
    Member

    With more spring pressure you want to eliminate the rotators.

    Sent from my S48c using The H.A.M.B. mobile app
     
    Sporty45 likes this.
  15. Neb Hillbilly
    Joined: Dec 20, 2019
    Posts: 337

    Neb Hillbilly
    Member

    I tend to favor 108s for how they come on the power but they don't like the N2O.

    Sent from my S48c using The H.A.M.B. mobile app
     
  16. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    Sorry, I didn't understand the bolded part.

    And yes, I am using a Quadrajet ;)
     
  17. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    Ah, OK got it ;)
     
  18. Firedup
    Joined: Feb 2, 2018
    Posts: 142

    Firedup
    Member
    from Oregon

    Not to hijack your thread, but I believe I am eventually in the same boat as you. What intake will you be using? Do you guys suggest the same cams with the stock intake?
     
  19. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    I don't have the intake yet, but will probably get a performer rpm.
     
    Firedup likes this.
  20. Firedup
    Joined: Feb 2, 2018
    Posts: 142

    Firedup
    Member
    from Oregon

    Have you decided on which cam to choose? Where to go for a custom grind cam?

     
  21. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    I'm leaning towards the Lunati VooDoo cam. Don't think I'll go the custom grind route. Mounted the pistons on the rods today. First time doing it and it went well. I was nervous doing it, but now I'm a pro! :p
     
    Firedup likes this.
  22. Elcohaulic
    Joined: Dec 27, 2017
    Posts: 1,418

    Elcohaulic
    Member

    I have screwed more good running engines up with long duration, short lobe separation drag cams then I care to remember. Pick something that will give you 18" or more vacuum at a smooth idle and give piles of torque right off idle. The street is so different then the drag strip.. On the street you need power now not in a couple thousand rpm..

    I have a stock 1978 truck 454 with 781 heads. All I did to it was advance the timing to 20 initial, 14 mechanical and took the vacuum advance off. It runs like a scalded cat and gets great gas mileage all on 87 octane..
     
    Sporty45 likes this.
  23. Budget36
    Joined: Nov 29, 2014
    Posts: 4,719

    Budget36
    Member

    Only thing I would add is you could rethink the rear gearing, that 454 will be fine turning 3.08's/3.23's, etc and like 65-70 MPH a bit better. My 454 is an LS5 from a '70 Vette, don't recall the cam spec, but supposed to 10.25 CR, only significant changes was adding a Edelbrock Performer 2.0 and Holley to it. Factory "rated" at 390HP. PU has 3.08's, tall tires (L60-15's) in the rear. Not posi, but could spin them or be very repeatable off the line. Stock converter, no creep and sounds like GMA's car at a stop light. Oh, TH400 as well.

    I know that doesn't help you with cam choice, but a 454 doesn't need low rear gear to get going.
     
    Elcohaulic and Sporty45 like this.
  24. Peanut port heads? Stock cam or an RV cam of some sort. The heads won't breath worth a flip and be pretty easy to over cam it.
     
  25. 6sally6
    Joined: Feb 16, 2014
    Posts: 1,305

    6sally6
    Member

    Check with Ken @ Delta Cams........in Tacoma Wash. They treated me very well. Told
    'em what I had and what I 'thought' I wanted . He made several suggestions and I am more than happy. They do A LOT of re-grinds and custom grind stuff for the PNW racers.
    Their price was in line with Howard and some others...actually less than Comp Cam shelf cams!
    Google 'em
    6sally6
     
    Firedup and Elcohaulic like this.
  26. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    Can you just open up the slots in the stock guide plates to fit the 3/8" pushrods? I have access to a milling machine and would be able to do it easily and accurately.
     
  27. Neb Hillbilly
    Joined: Dec 20, 2019
    Posts: 337

    Neb Hillbilly
    Member

    probably but 3/8th guide plates are everywhere. Where do you live?

    Sent from my S48c using The H.A.M.B. mobile app
     
  28. Sporty45
    Joined: Jun 1, 2015
    Posts: 871

    Sporty45
    Member
    from NH Boonies

    I'm in Barrington NH
     
    wheeldog57 likes this.
  29. Black_Sheep
    Joined: May 22, 2010
    Posts: 1,221

    Black_Sheep
    Member

    Sporty45 likes this.

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2020 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.