Comp Cams offering Nailhead Thumpr

Discussion in ''Da Nailhead' started by CameoInvicta, Nov 30, 2009.

  1. CameoInvicta

    CameoInvicta Well-Known Member

    Just browsing around for cams, came across Comps' website. They now offer their awesome Thumpr grinds for the Nailhead. I personally feel as if these cams would work GREAT in 'Nail since they have so much extra extra exhaust duration. Plus they sound pretty bad ass.

    The Thumpr specs out at 227/241 @ .050, 107* lobe seperation, and .478in/.465in lift.

    The Mutha Thumpr specs out at 235/249 @ .050, 107* lobe seperation, and .490in/.475in lift.

    The Big Mutha Thumpr specs out at 243/257 @.050, 107* lobe seperation, and .501in/.486in lift.

    I'm not sure that ANY of these cams will work in a stock motor w/o valve-piston clearence issues, in fact I'm pretty sure they won't. However, I'm going to call Comp sometime this week and ask. Just thought I'd pass it along.
     
  2. wkillgs

    wkillgs Gold Level Contributor

    Geeze, they're pretty radical cams for a street car. Forget about having power brakes that work in a parking lot!
    They do offer other Nailhead grinds, but they don't have them listed on their website.:rant:
     
  3. CameoInvicta

    CameoInvicta Well-Known Member

    Yeah, I'll give you that, they are kinda radical, however I think the Thumpr would work great (my dyno programs agree) in a 'Nail providing it would fit without clearence issues.

    In any case, it's still good to see that they are at least publishing cams available for the Nailhead.
     
  4. CameoInvicta

    CameoInvicta Well-Known Member

    During my layover in Atlanta, I gave Comp's cam tech line a call. The guy I spoke to, whose name I now forget, was a really nice and knowledgeable dude. He said that unfortunately they haven't actually tested a Thumpr in a 'Nail, and like with any build there is a chance for clearence issues. However, he did go on to add that in the future the Nailhead will be listed in their catalogs, along with the other Buick engines. I guess adding the 'Nail to their Thumpr catalog was just the first step.
     
  5. ahhh65riv

    ahhh65riv Well-Known Member

    I've posted this before, but I'm going to post my Comp cam specs here again as it seems appropriate. I'm surprised they dont have this one published as well...

    (formatting is off when this displays but there should be columns here)
    Comp Cams Part # 91-000-5.
    Grind#: B364 5201/5203 H 112+2
    Gross Valve lift: Intake .485, Exhaust.496
    Duration @.006 Tappet Lift: 275 intake 280 exhaust
    Valve Timing Open Closed
    @.050 INT 2 BTDC 42 ABDC
    EXH 49 BBDC 1 ATDC
    These Specs are for Cam installed
    @110.0 Intake centerline
    Intake Exhaust
    Duration @.050 224 231
    Lobe Lift .3130 .3200
    Lobe Seperation 112.0


    I definately don't like the 107* lobe seperation of the thumpers.:puzzled:

    Andy- Do you have the Desktop Dyno or what are you using? How does it like this cam?

    Erik
     
  6. CameoInvicta

    CameoInvicta Well-Known Member

    Erik, I do have two dyno programs, I will check and post when I get home. Right now I'm somewhere over Iowa.
     
  7. CameoInvicta

    CameoInvicta Well-Known Member

    Well, I did a comparison between the Thumpr and Erik's cam, the winner; Erik's cam.

    Is was close. In a stock motor the Thumpr made more average horsepower from 3500-5500rpms (~5hp), but less torque from 2000-4000rpms (~15ft lbs). Erik's cam and the Thumpr was both as efficient as each other through the entire RPM range.

    In a motor with mildly ported heads and headers, Erik's cam did even better. It had ~6hp more on average, and ~13ft lbs tq more on average. The Thumpr was more efficient though, the VE was 84% vs 83%.

    The Thumpr ground on a 112* lobe seperation angle was the best performer. Same average horsepower, only 7ft lbs tq less on average, and MUCH more efficient (87% vs 83%) through the entire RPM range.

    From screwing around with my dyno programs today, and in the past, the 'Nail REALLY likes a big split in the intake vs exhaust duration. Since the heads suck, it needs that extra exhaust duration/lift to really perform. I think something along the lines of 222/236 @ .050 on 110 or 112* lobe seperation angle installed 2 degrees advanced would almost be ideal.

    So in conclusion, the Thumpr is a good cam that sounds MEAN, but it won't fit in Nailhead w/o clearence issues, and there are better options out there. I guess if anything this thread can spark more cam discussion, lol :TU: .
     
  8. wkillgs

    wkillgs Gold Level Contributor

    Oh man, I could spend hours with a program like that! What's it called?
    Schneider has some grinds that look good:
    http://schneidercams.com/364401425hydraulicliftercamshafts.aspx

    Eriks Comp cam is very close the the Schneider 284-94H. I've been eying it to replace the old thumper Isky cam I have in my blue GS. I want some good ole street TORQUE!:laugh:
     
  9. CameoInvicta

    CameoInvicta Well-Known Member

    One of the programs is Dyno2000. I got it free online probably 5 years ago. It's surprisingly accurate. I put a 493 Mopar stroker combo my Uncle's friend dynoed in and it was almost dead on. In fact, it's even more accurate than the other set of dyno programs I actually paid for. Walt, PM me your email address...

    That Schneider cam would be a good off the shelf grind. Like I said, the 'Nail LOVES a split profile cam.
     
  10. funkyriv

    funkyriv Well-Known Member

    What profile would you grind on the TA roller cam for good low-end torque and top-end HP with modest head porting? Erik's, Schneider 284-94H, or?

    lots of old links to that software that are now dead after 5+ years. :(
     
  11. CameoInvicta

    CameoInvicta Well-Known Member

    I'll check it out and get back to you.
     
  12. CameoInvicta

    CameoInvicta Well-Known Member

    Well, I'd do something similar to both grinds, but split the duration even more. Something like 222/238 @.050 or even 220/240 @.050 on 110* lobe seperation angle, installed straight up. That should yield approximately 400hp and 500ft lbs tq.

    This numbers are assuming a 401 with mildly ported heads, stock 9.9:1 compression ratio, 850cfm carb on a dual plane manifold, with headers and a hydraulic roller cam.
     
  13. funkyriv

    funkyriv Well-Known Member

    Interesting. Does the model provide tq vs. RPM? If so, what RPM yields max tq, and what RPM is assumed for max HP? Whose DP intake do you have in mind for that engine? Thanks for the information!
     
  14. CameoInvicta

    CameoInvicta Well-Known Member

    With that combo, peak HP was at 5000rpms, and began falling off after that. With the 'Nails restrictive heads, it's difficult to get it breathe up top.

    Peak tq was at 2500rpms, but held within a few ft lbs of peak from 2000-3000rpms. It began falling off slightly at 3500rpms, and went down from there.

    As far as the intake - Marty is supposed to be coming out with a dual plane design sometime this spring. Otherwise, a Doc dual plane ought to perform really well, especially with a spacer.

    Does anybody have some flow numbers for a set of fully ported heads? I've seen the thread with Carmen's, Gessler's, and Steve Magnotti's. I guess I was wondering if anybody has gotten REALLY aggresvile and gotten some good flow out of a set of heads.
     
  15. CameoInvicta

    CameoInvicta Well-Known Member

    Oh, and in case anybody is wondering, this is the kind of potiential a ported, turboed, and roller cammed 'Nail has... :3gears:

    By the way, who is Ed Mosler? I finally found a set of flow numbers from him, and by the looks of it, he does pretty good work :TU: .
     

    Attached Files:

  16. funkyriv

    funkyriv Well-Known Member

    you might checkout Roger's (Riv1964) #'s

    http://www.v8buick.com/showpost.php?p=1349902&postcount=23
     
  17. roostriz

    roostriz Well-Known Member

    I have the DD2000 buried in a box somewhere. As I remember more about it I would think that even a ported NH cylinder head would flow about equvilent to a stock head on that program. Could you run the cam under those conditions to see what it makes?

    I might just have to dig mine out to play too. I kinda remember that you can enter your own flow data too right?
     
  18. CameoInvicta

    CameoInvicta Well-Known Member

    Yes, you can input your own flow data which is I don't rely on their "standard" numbers. I input flow numbers that others have posted/provided me with.

    Once you play around with the program you get pretty familiar with it and a few of its quirks. It might not ALWAYS be dead on with the HP/TQ figures, however it's a great comparision when testing different combo's.
     
  19. gsgtx

    gsgtx Silver Level contributor

    could you please plug my cam in. the car runs real strong think it might be a very good cam. 504-490 lift
    218-230 at .050 110 lsa 108 centerline intake opens at 1 close at 37
    ex opens at 47 close at 3 262-280 duration at .006 thanks
     
  20. doc

    doc Well-Known Member

    Ed Mosler is an old familiar name to us old fossils,,, old hot rodder/street rat/guru....used to hang out at the drag strips back in the 50's and 60's.... dont know if he is still alive.....:Do No: :Do No:
    BTW,,,,, be carefull when dealing with comp cams,,,, I used their cams for years and when I had 2 that went bad ,,, they gave me a hard way to go both times and both times it turned out to be the metalergy that was the problem.... the last time , I finally got fed up with the guys condescending attitude and told him that I was putting cams in cars when he was do do ing in his pants and to shut up and get me another cam.... they did.... :rant: :Brow: :Brow:
     

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