How much horsepower would 25ci give ya??

Discussion in 'Tomahawk Block Buildups' started by badbuik, Dec 12, 2018.

  1. badbuik

    badbuik Well-Known Member

    My current Tomahawk motor (5 years old) is 475ci, 13.5:1 compression, pretty sure the bore is 4.380 and a stroke of 3.95, and 7 in aluminum rods, made 830 hp on motor... I'm wondering, keeping that same stroke, what bigger bore can I go to? In the "heads up" world of racing, for me to be "competitive" I'd need to pick up about 1 second... Doesn't sound like much, but it is! On one nitrous unit, I've been 5.57, and if I could ever get the 2nd one to cooperate, the best I think I could run would be in the 5.30s... In my last x275 Class race, of the 32 car field, 3/4 of them were quicker than a 4.80, and in the finals, the cars ran 4.41 to a 4.42.....I know a procharger or turbo, can get me into the 4's, but that "budget" would be like $12K....So if i'd go to a bigger bore, pistons are about $1200, possibly new rods, $1200, where would that put me?? I did some off the wall calculations, a 4.40 or 4.50 bore would only yield 502 ci, not sure if this is an "ideal / efficient / legitimate" combination.... Just wondering right now........
  2. ken betts

    ken betts Well-Known Member

    Sounds like a good question for JW. He has a billion dyno tests! With the hp per cu. in. you have now 25"s more alone won't get you there.
  3. GS Kubisch

    GS Kubisch THE "CUT-UP" BUICK


    Are you still running a plate, or do you have a two stage fogger?

    Can your car get anywhere near minimum weight?
  4. hugger

    hugger Well-Known Member

    I wouldn't fool with it, for one reason you got room at 4.38 if something happens, at 4.5 your re sleeving. 475cid is the perfect size for boost,.....ha I'd concentrate on getting the second kit to working before I chased a few more cid
    sean Buick 76 likes this.
  5. badbuik

    badbuik Well-Known Member

    I have a fogger and an older NX Gemini twin single stage plate, both have been "blueprinted and flowed" by Steve Johnson at Induction Solutions. Was thinking about pulling the motor to throw bearings in it, but may just hold off until mid 2019. I'm in the process of changing out the Edelbrock progressive controller, I think it's been causing my current issues, and rewiring stuff. Then go out and see where I'm at, and hopefully get that 2nd stage to act like its supposed to..... I just laugh at the tech guy, when I x275 race, he says "your minimum weight is 2800lbs", I'm at 3355lbs... I just can't see trying to throw a bunch of money to possibly save 100 lbs, and that would be a huge amount, just don't think it's "realistic", even maxing out both units (700ish) of nitrous, I'm still slow, FAST, but not "competitive", and I'm still "having fun", frustrating, but FUN....
    Last edited: Dec 12, 2018
  6. badbuik

    badbuik Well-Known Member

    In the past, I actually thought about throwing my Tomahawk combo into a Fox body Mustang (Oh Crap!!!! No, he didn't say that!!!) BUT then it'd just be ANOTHER Mustang.....Nothing UNIQUE about that, "going fast with class" Right?!!
  7. Bens99gtp

    Bens99gtp Well-Known Member

    I think going with more stroke would get you more gain. 4.5 stroke would get you 542 cubes, 4.4 would get you 530.

    25 cubes for sure wont get you to where you want.

    not that you can straight figure hp this way. but your 830hp/475 cubes is 1.747hp per cube. so 500 cubes could be near 873hp. 542 cubes could be near 947.

    I know this an extrapolation but could be somewhat in the ball park.

    what do you have for heads, a new set wildcat heads if permitted might be an option too.

    in this class weight is key too, if you can it down that will also help.

    what transmission do you use.........some transmission eat more power to turn than others. known a few stangs switch to a Kilgore trans instead an factory base 400 and pick up near .6 in the 1/4 mile
    Last edited: Dec 12, 2018
  8. badbuik

    badbuik Well-Known Member

    To change to more stroke, I'm guessing $3k for the crank, my Moldex was $2800 like 10 years ago.... Nothing against the new Wildcat heads, they are awesome, BUT for what they'd cost, I could turbo or procharger, and make waaayyyy more power than putting those heads on, and still have some cash left..... Regarding weight, 65 Skylark light weight pieces, other than the hood, decklid, and bumpers, would be "custom" and that equals alot of $$$$$$$ and going front to back meticulously fabricating and changing stuff to save weight just isn't worth the effort ...... Trust me, I've been playing with this Buick for MANY years...... I appreciate the comments, but some of the replies are for people who have unlimited income!!! I run a th400, a very good, heavily upgraded piece, that is able to take what I throw at it....
  9. Bens99gtp

    Bens99gtp Well-Known Member

    might be worth s read.

    I think these new are in the 3k area. I haven't looked in years, but many parts inside the 400 spin at and faster than engine speed and have stop and change direction and spin back up again.... if I recall his setup saves some 30 lbs of internal spinning weight

    there is alot of hidden gains inside the transmission, it's one of huge reason we see stk and super stk guys running th350 and even the th200. the just spin easier. they cost to make I
    live though.

    trust me I understand racing on a budget, I have 2 kids under 6, a wife going back to school, and I fix cars in a small town without unlimited customers.

    but unfortunately racing in a pay to play sport and the faster we go the more we pay for less gains, so we all well know.
    sriley531 likes this.
  10. sriley531

    sriley531 M.M.O.G.

    Yep, "speed cost money, how fast can you afford to go" is always the truth.

    For the record, you may be a little fish in a big pond with the boys you play with, but myself (and I'd venture to guess many here) have always envied your car. It's a bad*ss piece as it sits.
  11. badbuik

    badbuik Well-Known Member

    I do appreciate the "input", and the kind words. I guess i'm kinda passionate about my Buick, "our" community, and others trying to make the best with what they got.. I am a firm believer in this philosophy, "you only go as fast as your wallet", and there's been a few times where my car "sat" for a year or more, waiting for my wallet to "catch up"!!!! I know putting this thread out there, it would get me thinking, even more with others opinions, and get others thinking too....
    Gary G.
  12. TrunkMonkey

    TrunkMonkey Well-Known Member

    "The All American 2019 BuFord Pegasus!!!"
    "Iron Bird in a Velvet Pony"™
  13. hugger

    hugger Well-Known Member

    I'm not a N20 guy so I may be way off base. But from what I've seen heavy hitting N20 combos run BIG primaries like 2 3/8 + and have BIG induction systems imo the single dominator and cast intake are stifling things up. I'm pretty sure that's what your running if I'm wrong my apologies

    A nice sheetmetal with properly sized runners would could pick it up close to 100hp in conjunction with another 1100+ cfm of air flow available to it, would need an aero scoop to take full advantage tho
    300sbb_overkill likes this.
  14. GS Kubisch

    GS Kubisch THE "CUT-UP" BUICK

    The point in which the 275 classes has gotten is beyond even money.

    You have to work in the industry or own a business that makes money without you being there. The travel and testing time to be competitive is a big hurdle at the level that most heads up classes have reached.


    You got a kick ass car that still has a lot of flavor. It will be a fan favorite no matter where you go. Enjoy it for that and refine what you have there.

    I would guess with the fogger optimized along with the rest of the car you could go low 5s on one stage
    Julian likes this.
  15. Bens99gtp

    Bens99gtp Well-Known Member

    heads up classes are alot different than the bracket racing I've been doing in my buick for the last 24 years.

    I think most racers have to a year or two off from time to time to get things in order and get built what they want.

    the x classes are crazy money to get into the tops of. what I know of turbo/blowers and fuel injection in that level is basiclky nil, but I would bet to put a set of twins on with the all the custom exhaust, intake, coolers, fuel system, and electronics to make right is going to be way above the 12k guestimate.
  16. Golden Oldie 65

    Golden Oldie 65 Well-Known Member

    My neighbor runs the x275 class in a `78 Malibu with a 449" small block Chevy. I'm pretty sure he said his car weighs in at 2,650 and that he said he could do it because it was a small block car. He had been running nitrous but this year got rid of it and went with a small Procharger, or at least he called it a small one, and he has run his personal best with it now at a 4.70 at 148mph. I don't offhand know what his best time was with the nitrous but he seems pretty happy with the Procharger.
  17. Bens99gtp

    Bens99gtp Well-Known Member

    I think big block up to 550ci are all in the 2850lbs min weight. so you could go 4.4 bore with 4.5 stroke and still be in the same weight break. not sure if boosted big blocks are even allowed???
  18. sailbrd

    sailbrd Well-Known Member

    A D-1X would give you over 1k hp. Head unit is under $4k, brackets are $100 worth of aluminum plate, crank pulley, EV hat, and some plumbing. You should have all the other expensive stuff like ignition and fuel already. Hell, if a hack like me can put a Procharger system together it should be duck soup for you. Do not see $12k to get to where you want using a Procharger.
    300sbb_overkill likes this.
  19. hugger

    hugger Well-Known Member

    Gary is at 13to1500hp now to put his 3350lbs in the 4.80s he will need 1500 to the tires. 12k for a correctly done blower setup is very realistic number, new cam, new converter, new pistons, 5k for a F1x head, 2k for brackets and whatnot , update the fuel system, 2k for the dual needle carb,...etc

    The 275 radial record is 3.8xx iirc, put it into perspective

    With the Bruders with a 4.29 In X275,...lots of power needed to pick up just a tenth when you get down in the 5's
    Last edited: Dec 12, 2018
  20. Bens99gtp

    Bens99gtp Well-Known Member

    would you still want carbs or would you want the adjustability of fuel injection at the level??????

    are boosted big blocks even allowed in x275. I dont see a minimum weight listed for bb on boost

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