2x4 intake flow & performance data

Discussion in ''Da Nailhead' started by ahhh65riv, Nov 15, 2006.

  1. doc

    doc Well-Known Member

    like I always say, speed equipment doesnt make much more hp, it just makes the engine get what it gets quicker.
     
  2. 56familykar

    56familykar knuckle banger

    Not bad for the first pull.
    Looks like you could use some timing. I've found it actually likes a little more lead.
    BSFC is kind of all over the place. I'd like to see a little smoother but not bad!
    What determined pulling at 3500? I think if you look at the curve, the beginning of the pull is very close to peak.

    Mike
    my .02
     
  3. ahhh65riv

    ahhh65riv Well-Known Member

    Here I plotted my breakin in run XL. You can see that the curve shape itself is pretty close to the others you have recently posted. (I just plan on moving them up the chart from here!) and promise I won't skew my chart numbers like Buick did that Walt found that he posted. When I get time I'd like to take those data points and put them on a normal graph like this rather than put torque and horspower on the same graph with two different scales on each side of the page.:puzzled:

    Yac- I can only hope for those numbers! Keep your fingers crossed! Honestly I dont give a RIP about HP. I want to see bigger TORQUE numbers! Isnt that what they say?- Horsepower sells cars and part, Torque wins races!

    I got a(reman) water pump, Gary got the jet/rods, so we will get a chance at some more runs again Thursday night. We will make many adjustments- timing carbs, cam degrees, plug gaps etc.I hope you all understand, but I am going to hold off posting any more pulls untill after we are satisfied enough with our tune, then we can start swapping parts:TU:

    BTW- Did I mention that I have IN MY HANDS an Edelbrock B262 and a Weiand 2x4 intake?

    Doc- If you had your way... A ported single 4 intake (Spreadbore probably) or modified with the dividers cut out at least with a HUGE 850-1100 Holy, would be your quest. Right?

    Later
    Erik
     

    Attached Files:

  4. doc

    doc Well-Known Member

    Yup, You got me peggd.
    What I am really intrested in is The power difference between the 2x4s and a big single [950 cfm or bigger] on a hogged out single intake. I would bet that the single will do almost as good as the duals.
     
  5. 56familykar

    56familykar knuckle banger

    Hey all~
    I have flowed an Eelco 2x4 intake now, thanks to Bob for that! I have also flowed the Kring Intake for the 48 IDA webers.

    the Eelco 2x4 flows about 15-20 cFm MORE than the stock 4 intake.
    Naturally, The Kring LOG intake flowed the best thus far.
    I'm working on porting the stock 4bbl intake. (Hope Doc is listening) to see if there is any air flow based on the flow bench. Interesting fact, cutting out the divider didnt show any signifigant gains on the flow bench but I believed it wouldn't. I think that is a more accurate test for the dyno and real world driveability due to fuel distribution.

    Mike
     
  6. funkyriv

    funkyriv Well-Known Member

    The Buick literature curves match the advertized power and torque very well. However, in Ted's "Nailhead Dyno'd" thread multiple comments are made that Buick overstated the performance values.

    If Buick overstated the torque/hp specs, how was the Buick data generated? Generous dynamometer calibration? Were the Buick curves from a circa 1960's engine performance model or estimation, so not measured data? :Do No:
     
  7. gsgtx

    gsgtx Silver Level contributor

    does 15-20 cfm more, make alot of difference in performance?. thanks
     
  8. flynbuick

    flynbuick Guest



    They used old dynos with dial gauges and nothing digital. There will always be some variation from dyno to dyno unless they are calibrated relative to some common denominator. The rpms used to take a measurement can vary the numbers.

    Buick for sure fudged engine output numbers. A 70 RIV engine rated at 370 hp was the same as a GS 455 nonstage engine rated at 350 hp. Frorm D. Manner's factory dyno tape we know it was really about 360 hp. A 70 stage 1 was rated at 360 hp but was 376 in fact.
     
  9. 56familykar

    56familykar knuckle banger

    Yes, 15-20 CFM will make a difference in an engine that is naturally suffocating to support itself!.

    As for dyno numbers. There IS a standard calibration out there. And you cant compare '70 model stuff with the earlier due to changes in engine ratings.
    I can MAKE an engine show 15 or more HP on the dyno by changing the RATE I allow it to accelerate.


    Mike
     
  10. doc

    doc Well-Known Member

    As I remember, there was a change in the way the factories rated hp along in the late 70's or so.
    I noticed that in my 1965 factory shop manual the hp is listed as 325 for the 401 engine [brake hp] and 56.11 Taxable hp. [taxable hp was the hp available at the rear wheel after going thru the drive line.] Taxable hp is what really moves a car.
     
  11. doc

    doc Well-Known Member

    A lot of mods dont neccessarily give more horsepower, they just allow the engine to accellerate quicker, giving a ''seat of the pants'' feeling of gaining power.
     
  12. 66gsconv

    66gsconv nailhead apprentice

    Erik- I hope no news is good news. I agree with you. A heavy riv. is looking for all the torque you can find. Thanks for the sacrifice ($$$$$$$) so everyone can find out what really works.

    Doc- after talking with Tom T about this 1x4 mod. I went ahead and did it. It is basically what you are talking about. I have it on the car now with a 950 and drove it last sunday like this. It might be a hard to beat combo on the nailhead. I also am getting my eelco and edelbrock carbs ready. In a few weeks I am trying to drive over to the dyno and compare the two set ups.
    We will see how that works out

    Mike- Thanks for flowing the eelco. I think there is a lot to be said about the way your testing these intakes. THanks.
     
  13. 56familykar

    56familykar knuckle banger

    Thanks Bob! And to everyone, I started a thread with Flow numbers. Here is a copy/paste of that in case you miss the thread:

    Greetings All~
    Many have wanted some good quantative data on intakes and etc. I have had the opportunity to do some of that with the assistance of our fellow Nailheader's.

    Here is a basic run down. I have more detailed stuff for those interested.
    Port by itself on the flow bench followed by the Stock 4bbl, The Eelco 2x4 and then the Kring Log intake.
    .100 65.5 63.4 64.0 63.8
    .200 124.0 117.3 121.3 122.8
    .300 166.9 148.8 158.4 159.8
    .400 196.7 169.2 183.7 189.5
    .500 219.8 182.5 201.2 212.0

    I have flowed these all higher than this. I have also flowed both upper and lower plenums all in .050 increments.
    Overall, the 2x4 has a 15-20 cfm increase over a stock 4bbl.

    Mike
    More to come later

    Eelco-Portland OR 503-651-3352
    Don Kring, Nailhead Specialists Indiana 260-493-6078

    Both have websites
     
  14. 56familykar

    56familykar knuckle banger


    I'm not that far yet doc but I'm working now on getting a stock 4bbl to perform. As of yet I've only done 1 modification and seen 1.5 cfm in gains.
     
  15. ahhh65riv

    ahhh65riv Well-Known Member

    I have learned a lot over the last few days about how an engine dyno works.
    It was an RPM selected that was higher in the RPM range to pull from. As the computer part of the dyno appllies the load, the engine "bogs" down. This setting determines the lower range in the RPM you start applying the pull (load) from. The lower it is, the harder it is for the engine to recover and pull out of the load. Basicaly it was kinder for the engine for the first reference pull, as it is barely broke in!

    The funny thing is... since then, we have pulled from lower than 3000, but most pulls are made from 3000. Craig Schuck (the operator/owner) said out of all the many race engines he has dyno'd, and thousands of pulls, he had never seen any engine ever recover out of a 2500 dyno pull before! :laugh:
    That says a lot about torque!!! The ol' nail had no problem!

    Thanks Mike for the Eelco flow bench numbers! Someone will have to help by teaching me how to understand those numbers though.:Smarty:

    Changing intakes this weekend.:Brow:

    Erik
     
  16. ahhh65riv

    ahhh65riv Well-Known Member

    We switched to the Weiand intake. I have to say she is a beaut!

    :idea2: We have come to the conclusion that the included calibration and metering chart for these carbs is for a single four application only. We were using the given chart for the 1805 & 1806 carbs that we have. We have to go to a different chart and metering rod/jet kit (Edelbrock calibration kit#1486) as the Dual quad arrangment is different. We are seeing differences (lean/rich) for the 3 stages of tuning: Idle circuit, primary, and secondary that means more jets and metering rods needed! We wont have the kits until the middle of next week.:Dou: We will consult with Edelbrock on Monday to confirm.

    Erik
     

    Attached Files:

  17. tyoneal

    tyoneal Active Member

    ===========================================
    "Here is a basic run down. I have more detailed stuff for those interested."

    Yes, Yes, Yes, always interested. Please post or email.

    Have any ported heads been flowed?
    ============================================
    Question for everyone!!

    Even though the heads characteristically don't flow that great, would you still expect the same % increase on a Nailhead if it was Blown (Turbo, Supercharger) as you would any other engine that was Blown??

    This should fundamentally be correct, right?

    Thanks,

    Ty O'Neal
     
  18. tyoneal

    tyoneal Active Member

    ==========================================
    I think the peak Torque on the Nailheads (at least the 425 was at 2800 rpm) so they might even handle a pull from 2000 rpm. It would be cool to see how low they can go before they can't pull out of it.

    Almost all race engines I've had didn't start making good power till at least 3000 rpm's, but these are a totally different animal. They pull more like a Diesel than a Gasoline Engine. In fact I think "Banks Performance has a Diesel that will out Rev a Nailhead, and still be making power!)

    The Nailheads would probably really raise Hell on the 1/8th mile.

    Ty
     
  19. 56familykar

    56familykar knuckle banger

    We pulled our 401 out from 2900. It does take a lot of servo on the dyno to pull that low anyway but peak torque was 3600ish. I dont think pulling a nail down at 2000 would be a good idea. That's pretty low for FULL LOAD, something it will never see. It is also really rough on the dyno itself.
    Ty, send me an email and I'll be glad to send the .050 increment flow data.
    It should be noted that the flow numbers are on a PORTED intake port. They are a little down from a couple tests previous but I've still got work to do and when you go too far, that happens.
    Keep up the good work Erik!
    I want to thank again the people who have sent me an intake to test.

    Mike
     
  20. 56familykar

    56familykar knuckle banger

    Even though the heads characteristically don't flow that great, would you still expect the same % increase on a Nailhead if it was Blown (Turbo, Supercharger) as you would any other engine that was Blown??



    any engine will see an increase in power with forced induction. It should also be understood that Nitrous does not care what it is put in. A '50' shot will add 50 HP to a 1000 cubic inch tank, OR a 5hp Briggs!

    Mike
     

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