First Test- KBR Super Wildcat Billet heads

Discussion in 'Race 400/430/455' started by Jim Weise, Dec 14, 2018.

  1. GS Kubisch

    GS Kubisch THE "CUT-UP" BUICK

    I've been thinking the same thing. It's impossible to make an apples to apples comparison considering all the other parts needed to support the heads.
    badbuik likes this.
  2. Jim Weise

    Jim Weise EFI/DIS 482

    Just have to do the math.. An air pump's potential is directly related to it's flow capabilities.

    A fully optimized race motor combo, rule of thumb, makes 2.5 HP per cfm of max head flow. Comp eliminator motors and Pro
    Stock are typically 2.6-2.7.

    Cast heads tend to peak around 400.. so 400 x 2.5= 1000 HP..we have seen this in 8000 rpm cast head tomahawk builds give or take 50 HP..

    Ken's heads are about 500 cfm at .900.. so we should realistically use maybe 490 as a flow rate.. the math says the max combo should be capable of 1225 HP. I think that number is well within reach, in a 15-1 combo, with a refined intake and camshaft combo.

    If you see numbers that are way out of wack with that formula, you have to wonder.. at that point in time the wise racer just notes the discrepancy and then compares that number to the quarter mile speed the car it goes into produces, of course taking into account the specs of that particular car. If it's not within 10% of what he math says it should run with that crank HP, then you can draw a conclusion if you wish to. If it runs what the math says it should, then you conclude that the build is exceptional.

    I expect that Ken's heads will be 200-250 HP better than you can do with the current cast head all else being equal.

    Julian likes this.
  3. GS Kubisch

    GS Kubisch THE "CUT-UP" BUICK

    Regardless, it's a new engine from the camshaft out.

    I think 1225 is conservative.
    Julian likes this.
  4. ken betts

    ken betts Well-Known Member

    Thank you to all who have input. I can only say that is a lot of horse power for a "bracket motor". I was teaching kids tennis when I got the numbers. I can only say you should have seen the smile on my face.
  5. Bens99gtp

    Bens99gtp Well-Known Member

    I'm sure in time we get a direct s2,s3,s4,in head shoot out. for now they just need to get all the testing in to get the info they need to feel good about releasing and moving forward.

    I think the mid 1000hp is a great number, with only a few baseline pulls I'm sure with timing, carb work, cam timing these numbers would be closer towards 1100, for a motor ment to 200-300 passes b4 refresh that crazy good numbers, at 7000 rpms this motor should live very happily for the expected service duration...... great work and look forward to seeing more.
    ken and your team thank you for pushing the technology and parts available to us to the next level
    Julian likes this.
  6. BuickGSrules

    BuickGSrules Gold Level Contributor

    I could live with at 1000 hp bracket motor that just goes rounds and rounds and rounds and...…..
    slimfromnz, Briz and sriley531 like this.
  7. Jim Weise

    Jim Weise EFI/DIS 482

    Just need more time and testing... and possibly a bigger air pump under them.. a 605 would be ideal, but swinging that 4.750 crank would be a challenge in our crankcase.. a 572 might be a more practical build.

    A better solution is actually still staying undersquare at 4.750 stroke, and then widening the pan rails and the bore centers and bring the bore up to around 4.800..

    a 688 would tug nice and hard on those heads and get the airspeed up to where we need it, yet keep the rpm out of the stratosphere..

    Luckily I know a guy that wants to do a 5.3 bore center block.. :eek::D

    all kinds of fun possibilities with a 500 cfm head.

    All that is in the future, but for night now, we are going to concentrate on this combo, we need to pull this one down, insure that everything is happy together at this level, and then take the next step with cam and intake.


  8. hugger

    hugger Well-Known Member

    That bullet is a BAD BIAOTCH,...that the average guys just cant replicate,...not because of money but because of the engineering and execution if they could they would've already. Not dissing anyone but that thing is an ACCOMPLISHMENT in many ways
    ozarkian, PGSS and GS Kubisch like this.
  9. Julian

    Julian Well-Known Member

    This is going to go off topic but please expound.
  10. badbuik

    badbuik Well-Known Member

    Julian, "GS Kubisch" Gary K, has an awesome Tomahawk powered BBB, NA makes big power, and has several custom engineered go fast goodies! All stuffed into a very nice, light GS/Skylark. His hard work, gives many of us in this community Motivation & Inspiration, and tons of respect...
    John Stevens and ozarkian like this.
  11. Bens99gtp

    Bens99gtp Well-Known Member

    if you get a chance to see Gary's car. if he has time just stand and look, garys build took several years of planning and fact if I understand he almost dropped the idea......
    his motor I'd truely a work of are, many well thought out, 1 off custom parts. I think his motor is turn upwards towards or above 8800 rpms. his head are far from your average bolt on s2 heads or you average port job........they are stretched to the very edge of what can squeezed from them.........and I know when we talked they are not 500cfm.

    garys stuff is truely a major accomplishment, an awsome motor and car. I'm glad he worked through and got the results he was looking for.

    Gary is a great guy and if he has the time he will talk to about he stuff and yours, he has helped me for years with some thing going on with my car from time to time.

    but his stuff is not something most of us can build, and I dont think he will get 200-300 passes between refresh.

    his motor would be a great candidate for a head to head competition.

    we all are crazy excited about what Kobe has going on, we all just need to them the time they need to make a great product for us all get the chance to enjoy.

    cant wait to see what some of these 570+ motors can belt out. I wont be able to touch these parts on my budget, but am happy they are coming out
  12. Julian

    Julian Well-Known Member

    Hopefully Gary will bring it next year's Nats!
  13. Bens99gtp

    Bens99gtp Well-Known Member

    I dont want this thread to get off track, this is about the awsome results of these new heads. it's clear to see how much time, effect, money and pride has gone into these and cant wait to see them in the real world, pushing buicks faster and faster.:D
  14. Jim Rodgers

    Jim Rodgers Well-Known Member

    Nice work!
  15. BQUICK

    BQUICK Gold Level Contributor

    Is there any concern regarding the oil pressure going from over 100 to 53 at the end of the pull?
  16. Jim Weise

    Jim Weise EFI/DIS 482

    Too early to say for sure James, would like to think there will be serious KBR stuff under the hood, but heck, this is the first year for this car, I have not even seen it yet... I will be racing it in a deal with Mike Erickson, who owns this billet head motor. I probably won't see the car till spring..

    Funny you should mention it, I was actually putzing around with the block for this new car last night.. It's a really nice 76 block that happens to be one of the thick ones, that I have had around for a while now.. I am going to build a 476ci combo for this one, with a set of 300 cfm Iron heads that I bought off George Sweesy years ago.. That will be the everyday bracket motor, around 600 HP on E-85.. Then I always plan on having something wilder to put in it, to go to the Buick events, but most likely that motor won't be available this year.. but who knows?

    Certainly in the future, this car, and the 70 GS tube car on the drawing board now, will be used to test many of these new KBR combos and products.

    Here is a picture of the new car on the bottom and the home for this new motor, Mike Erickson's Tube chassis Regal, on the top..


    And ya.. we will be putting the wheelie bars back on Mike's car... LOL..

    BuickGSrules, Julian and 1972 Stage 1 like this.
  17. Jim Weise

    Jim Weise EFI/DIS 482

    You bet there was Bruce.. this is the only pull that went to 7500, and that stationary engine oil pressure phenomenon has to be cured before we can test any higher.. We tried a bunch of different things that day, I have had moderate success in the past with this engine, by just adding more oil on the dyno, but no such luck that day.. These Tomahawks, with a wet or dry sump, seem to be more affected by a lack of g force on the dyno than any other Buicks, I suspect that it's because the crankcase is physically smaller, because of the thicker block and design. I have tried every windage tray out there for one of these things, seems to have little to no effect on this particular issue. This motor has a full length custom Moroso Diamond stripper unidirectional louvered screen in the pan, front to rear. Same setup I use in several Block girdle Iron motors, with big stroke cranks, and we had no issue at all with those engines.. they would maintain 70+ psi in a slight upward slope, or a flat line, all the way to 7000 rpm, which was the rpm limit for those builds. No reason to think oil pressure would have been a problem to 8k. But the same setup on this block, does not work the same way..

    I am working on a full length solid windage tray, similar to what you would see on the bottom of an LS motor, as the ultimate answer as to if we have windage frothing the oil, or blowing it away from the pickup.. I will be testing that in Jim Byer's engine here soon, as his supercharged motor has to be able to be tested at 7500+ and that motor should make several hundred more HP than this one.. so it is even more critical for him.

    In the car, I have seen a couple of data recorder equipped cars with Tomahawks, and various oil systems, and they seem to not be a problem.. and all my customers have reported to me that on the track, there is no oil pressure concern. And the proof is in the pudding, so to speak, this motor has 700 plus passes on it, and there have been no oiling related issues.

    Oil pressure was maintained at 60psi or above during every other pull that day.. it's typical that it dropped from around 100 psi, to mid 60's during the pull, and there was little we could do to alter that.

    I did check oil pressure at two spots, at the front and rear of the block up on top.. that was a surprising result.. the rear reading was 10psi higher than the front.. and the oil is being fed into the block at the traditional oil pressure switch location, which in a Tomahawk is a 1/2 NPT hole. It's fed via a -10 line, thru the Oberg, which is capable of flowing 31 gpm, or about twice what he motor requires.

    A couple of these high profile Tomahawks have not lived long after the dyno, and odds are they were hurt on the dyno, nobody knew it until it blew up in the car, in the first few passes. Not too much of a leap to imagine low oil pressure at high rpm during testing was a factor in these failures.

    Trust me, I was watching the Oberg like a hawk.. and we were careful with it.

  18. BQUICK

    BQUICK Gold Level Contributor

    Due to priority oiling I was told that the 10lbs per 1000rpm rules is out the window? I'd still like to see 75 at 7500....even if it costs a few ponies.....

    JESUPERCAT No Slow Boat

    Jim are you thinking of using an external oil pump. I will be ordering my new Daily engineering pump this week for the dragster. You can use it for the next testing if you want.
    90 -100 psi work load at all rpms.
    Let me know
    Staged70Lark likes this.
  20. Jim Weise

    Jim Weise EFI/DIS 482

    I agree with you Bruce... I got nothing for 40 psi at 8000... no way I could let a motor do that on the dyno, and not have the pan off it to eyeball the rod bearings, before it went out the door. I don't care about priority oiling, you have to have the pressure to force the oil thru the crank to the rods.

    I would like to see 60-70 Psi at a minimum, and expect for the extra 500 rpm in this pull that was the case during out test session here, and has been true for every Tomahawk I have had on the dyno.

    And, knock on wood, we have not hurt one yet..


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