Just for shits and giggles, I ran the peak piston acceleration numbers on a 3.75 stroke x 6" rod 400 at 11,000 rpm. They exceed 8000 G's.
LOL I used to "prove" to the sbc brainwashed that my stock shortblock 351W would spin 8K with ease that way- that little switch on the back of the tach
The expolding part has to do with how it is put together. I know for a fact that an SBC will spin eleven so twelve really isn't that big a stretch.
Ran a 350 sbc in my '56 with a 5spd Nash behind it, launched the car at 8700 shifted at 8500. Short-block was basically stock parts, just well prepped and balanced, all the money was in the heads!. Went 11.0's what a great ride!
Friend of mine ran a SBC in C/MP back in the '60's. Wound it so tight the "experts" just shook their heads. Big problem he had was getting valve springs that would prevent float. Don't remember exactly how long they lasted but he got good at changing them between rounds!
I don't know about the origional question but since then there have been some absolutely UNBELIEVABLE posts. Aparently the posters have no idea of what takes place in the valvetrain at this RPM and the cost of the components if they were even available. If by chance you've got the parts to do this I know where you can make a fortune by just stopping by any competitve NASCAR shop, you won't need a gun, just a big truck to haul away the gold. I'm refraining from calling bullshit because no self respecting bull or his pile would get caught near some of this. Frank
Well, you got one thing right anyway, you sure as hell wont find the valvetrain parts in a NASCAR shop, and I really dont know why in the hell anyone would even think to look there! The springs in question sure as hell wont last 500 miles! As far as the availability of the parts, they arent hard to find, any shop that builds motors for comp elim. will have them, and they have been around for decades. As far as having any idea about the parts, I have seen them, handled them, and assembled them. My mentor built MP and Comp motors for a living in the '70s and '80s, and was the local Booth-Arons distributor. Yea, the shits pretty deep alright.
I never saw a 11K 406 either. Some of the last SBC comp eliminator engines I built & ran (mid-late 1980's - in the 280 cube range) would go to around 11,600 at launch and I shifted around 11,200 on gear changes. To do that & stay together, it took alum rods, messaged/gas ported pistons, completely worked aluminum heads, ti valves, roller cam @ .800+" lift, roller rockers with a stud bar & and the biggest, baddest valve springs I could get my hands on from Bob Kamp at K-motion at the time. Ran them like that for years and they did run close to the national record at the time. Everyone else was running theirs about the same rpm's as I was, so mine wasn't special. But, valvesprings these days are WAY better. Since you mentioned cranks; Yes there have been rifle drilled rod throws on cranks for many years - AND rifled drilled mains as well. The oil passages Obviously are drilled differently than what you are thinking or have seen. I have a friend with a 5.675" Pro Mod crank that you can look straight the crankshaft (from the snout, clear thru the flywheel end on the mains) which is simply capped at the back with a freeze plug and a stud for the balancer on the front plugs it there.. There's still more than 1 way to skin a cat.
Watch the tach. Pretty sure its not set on 6 cyl. http://www.streetfire.net/video/bruce-perkin-gsm-comp-firebird_144609.htm
Yes rifle drilled oh 180* too with dry sump titanium valves oh and I should have been more specific about the rods they're forged aluminum H beam. Dry sump and rerouted oiling that's how it works. I was also talkin less than 3" stroke. You should perhaps read up on MP & comp eliminator classes of drag racing. Oh ya less than 300 cubes. Ive seen one go 15000 on the dyno right before the valve train came apart.
Actually frank most of the time I agree with you. But the fact is that I do know what it takes to make one spin. I also know that building one to go 1320 and building one to go 500 miles is an entirely different game. The only things the two have in common is that they are internal combustion engines. I used to tune a pro-comp car that the valve springs were so stout that you had to unload them between rounds, not likely that the engine would have gone four or five hundred miles without a catastrophic failure but it would go real fast for a short distance more than once. I'm not sure where the cheap part came into the equation on this thread. You can build a stout small block cheap or relatively cheap in the whole scheme of things but race motors are not and have never been cheap. Speed costs money . . . I don't know for a fact that the car in the utube was spinning 12K. All I saw was a car launching and from where I am sitting it isn't even possible to see what it had under the hood. But I am pretty sure that if you throw enough money at one you can make it wind pretty tight and I really don't believe that 12K is unobtainable.
I took a look at the video twice. Looked to me like he was shifting around 10k. I couldn't see the numbers but guess it is a 12K Autometer unit.
10,000 11,000 12,000 all big revs. I have watched valve spring checking (and replacements) between rounds on Bruce Perkins car many times. If the Nova story is true it would have to be the same valvespring process. No one is driving these on the street unless they have more moey than sense. I had a lot of fun driving an 8,000 rpm 331 small journal sbc on the street, but that was enough work to keep together. Falcongeorge it is such a small world that I live across the river from you!
Probably right across, I am in North Surrey. Note how high the tach goes just before launch. Launch rpm is usually quite a bit (like around 1000 rpm) higher than shift rpm. Yes, valvetrain maintenance is a constant chore at this rpm level, checking the seat pressure between rounds to spot a spring that is on the way out. Titanium springs have made things last a little longer, as the spring mass is less, so the seat pressure can come down a little. Some of the spring pressure goes into controlling the mass of the spring itself. Driving these motors on the street is out of the question, and I have experience with some pretty hairy stuff on the street. For one thing, the gas ports would carbon up fairly quickly and then the rings wont seal.
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