dyno numbers 425 stroked nailhead

Discussion in ''Da Nailhead' started by gsgtx, Jun 2, 2013.

  1. 66gsconv

    66gsconv nailhead apprentice

    Joe, how does it run now compared to last summer with the smaller tires? Can you feel the TQ loss down low? How about from a low rpm punch rolling along? The head work I did was to try and even up the intake runners to as close to the best one you had. I tested all the runners and the best was 225 at .500 and 230 at .600. The worst was 212 at .500 and 216 at .600. Now they are all 220 to 225 at .500. Would of took a longer time to get them all even. I bet any heads you have someone work on would be all over the place unless they took the time to test every runner at least a few times and they are going to really hit you in the wallet for that :Do No:
    At least we are seeing what kind of power can be made with the nailhead and cfm #
     
  2. CameoInvicta

    CameoInvicta Well-Known Member

    The taller tires definitely didn't help, but by how much is anyone's guess. What diameter are the new tires, and what diameter were the old tires? You could try bumping up the timing a little, with the retarded cam it might need a little additional advance.
     
  3. 66gsconv

    66gsconv nailhead apprentice

    Thanks for posting this info Andy. But I do want to say thanks to Joe for taking the time and money to do the testing again. I personally am getting some info out of this. One of these days I guess we will just be happy to go out and start our nailheads and have a nice peaceful ride to the dounut shop :sleep:.....NOT:laugh:
     
  4. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    I could see how the taller tires might hurt the low end torque some due to additional rotating mass plus in effect lowering the gear ratio. However, on the track if the car was previously starting to fall on its face towards the end of the run, the taller tires will help eleviate that. So, while the numbers may look a little out of place, how it performs may be an improvement. It should grip better off the line plus gain MPH at the other end.

    Those are some nice numbers and good job to Bob for port matching all the runners. I think you will see more improvement than you might think. Now you just need to get to the track, make some passes, and then calculate your true effective HP/TQ numbers. In the end its what's on the time slip that counts. :TU:
     
  5. gsgtx

    gsgtx Silver Level contributor

    they are only 3/4 inch taller might be just worth 2-3 HP,TQ. one size smaller jets maybe 3-5 HP,TQ. synthetic oil 5-6 HP,TQ. 2* more timing 2-3 more TQ down low. these numbers are all a guess, but it would of been nice to get the peak TQ back to 550 TQ and get 15 extra HP to make 440 peak HP. Oh well maybe next time. I would keep the cam retarded with this small of a camshaft, it moved my peak HP up 80 rpms from the last dyno test.
     
  6. CameoInvicta

    CameoInvicta Well-Known Member

    Joe, the taller tires would be like reducing the gear ratio by about 2.8%. Looking at it purely based on the gear ratio and lost mechanical advantage, that would essentially make up all your lost low end.
     
  7. 66gsconv

    66gsconv nailhead apprentice

    I am still wondering if this many cubes might like the 2x4. Good power for such little air :TU: Just wondering how you feel the traction might be for a 60 time? Does it seem to " fall on its face " up top? I would play with the carb. Might be a little left in it there:TU:

    Also I just wanted to say that of all the dyno test and threads in the past this is the only one I remember knowing what the heads and intake flow. It is a little more info that we can use
     
  8. gsgtx

    gsgtx Silver Level contributor

    . even the big street tires cant handle the low end TQ. At 45 mph on a 45-50 degree day{cold roads} when I kick my 2-speed in passing gear the car will go side ways, with only 323 posi. I will try to get some track time. i have some new M&H slicks to bring.
     
  9. 66BulldogGS

    66BulldogGS Platinum Level Contributor

    Yeah, I wouldn't imagine the streets to hang on real well while on the road. But the track is a little different. I don't know much when it comes to actually going down the strip, as I have never done it myself. Just what I have picked up from talking to others. That set of slicks should cure that problem.
     
  10. 66gsconv

    66gsconv nailhead apprentice

    That's awesome. If that don't get you into the 12s. Even with the 2 speed and 323 gears :TU:
     
  11. gsgtx

    gsgtx Silver Level contributor

    Bob, after the track time I will try the 2x4. it pulls to 5500 it does drop off after 5700, I shift at about 5300 rpms and it does not dog down going into high gear it just keeps pulling. hoping to get a 1.80 or lower 60ft time.
     
  12. gsgtx

    gsgtx Silver Level contributor

    never made it to the track. but I do have the 2x4s with the mild ported eelco intake back on. should be back to the dyno this Monday. seems to run good. Andy, I will email u the results if would still post them. thanks, Joe.
     
  13. 66gsconv

    66gsconv nailhead apprentice

    Hi joe, i havent been around much, i am still working in Tulsa. Seen this so i thought i would reply. Last time we talked you said you thought the 2x4 might run a little fsster. I always wondered if 446 cubes might like the eelco. What size carbs you running? Also mabey later in the summer i will send you my 950 quick fuel holley style carb to see if it picks up any on that 1x4.:idea2: just wanted to add. Thanks this is very good info for the few of us that are into building there nailhead to run stronger than stock. We can see what a small stroke, decent cam and some head work and intake swaps can do. Sure tells me what direction i am heading with mine
     
  14. Bigpig455

    Bigpig455 Fastest of the slow....

    And I apologize, I haven't been around much either.....Bob, I know your dying to know what the hogged out Q-Jet intake will do on the track and I haven't been able to make it yet either...

    my hybrid 800 CFM Q-Jet ran great, but the o2 meter said super rich so I put my trusty 750 back on and the car runs fantastic on the street. A little loss or torque but a beautiful "ripping" sound as the revs come up and it transitions into the secondaries and you get pressed back into the seat. from 30-60 mph the car just JUMPS through the top of first gear.

    It never made that sound before, and I cant describe it any other way...it's almost the same sound an an old 6 cyl BMW M3 makes, only deeper and V-8er. It's awesome.
     
  15. 66gsconv

    66gsconv nailhead apprentice

    So rhett you are saying the intake made a seat of the pants defferance? Thought it would really rsond to a engine with slightly hotter cam and heads. I think joes. Ported intake worked out ok also. 2 by 4 might still be better on bigger cubes. Although you cant beat the q jet plenum. Good luck....sorry joe, back to topic
     
  16. Bigpig455

    Bigpig455 Fastest of the slow....

    Yep - my bad for the hijack. yeah, midrange feels great and I just haven't spent enough time at redline to know.
     
  17. gsgtx

    gsgtx Silver Level contributor

    no problem any nail head talk is good. Bob the intake you did really helped a lot. but the stock intake is not a high rise and has small runners, you can only do so much with it. maybe this dyno run will answer the age old question what is better a single 4 or 2x4 on a built nail head. 2x4 is higher rise and bigger runners.
     
  18. CameoInvicta

    CameoInvicta Well-Known Member

    Sounds good Joe!
     
  19. 66gsconv

    66gsconv nailhead apprentice

    Joe, if you make it to dyno good luck. Hope you get your goal :TU:
     
  20. gsgtx

    gsgtx Silver Level contributor

    have the dyno sheets in front of me. he has not sent me the email yet. here are some numbers. engine hp went up 6 hp at peak. stayed up all the way. at 5600 rpms it was up 10 hp. so average hp was up at least 6 hp. peak tq was the same. after 4400 rpms tq was up about 8 lbs and stayed up all the way to 5800 rpms. average tq up at least 8 lbs.
     

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