Stock Eliminator secrets?

General engine tech -- Drag Racing to Circle Track

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tenxal
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Re: Stock Eliminator secrets?

Post by tenxal »

1972ho wrote: Wed Oct 14, 2020 10:41 amWOW close to 15000.00 in headers...
Now that's some creative ciphering..... :roll:
1972ho wrote: Wed Oct 14, 2020 10:41 am....that is more than I have spent on my whole car and it runs over a second under the index and that’s with a standard set of 2 inch hooker headers with a merge collector.WOW ain’t that something.
Looking forward to you posting pics and further documenting this car and your achievements.
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Re: Stock Eliminator secrets?

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[/quote]

THE lowest I’ve ever heard on a SBC (8 cylinder of course) was 7 lbs/ft of rotating torque... 1 lbs/ft difference could be error.

THE lowest I’ve ever witnessed was 11-12ish rotating and I’ve been fortunate enough to have been around a lot of very sharp and competent builders/racers.
[/quote]

Just finished up a SBC NHRA Super Stock short block today - 4 lbs. breakaway and rotating, 15/50 break in oil on everything
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Re: Stock Eliminator secrets?

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This is the car
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Jeff Lee
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Re: Stock Eliminator secrets?

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1972ho wrote: Wed Oct 14, 2020 1:42 pm I’m not really trying to be a smart azz are anything but that is a chuck of doe for a class that only pays 1200.00 to win if that and hardly any contingency.If I spent that kind of scratch I would be 2 seconds plus under if not more.
Really??? Is the H/SA Mustang picture down the tread your car? I’d like to see one of those Cleveland's go -2.00! =D>
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Re: Stock Eliminator secrets?

Post by smeg »

This is a really good thread, keep it going please. How hard are you guys turning these things at the stripe?
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Re: Stock Eliminator secrets?

Post by jed »

LSP wrote: Wed Oct 14, 2020 10:43 pm
THE lowest I’ve ever heard on a SBC (8 cylinder of course) was 7 lbs/ft of rotating torque... 1 lbs/ft difference could be error.

THE lowest I’ve ever witnessed was 11-12ish rotating and I’ve been fortunate enough to have been around a lot of very sharp and competent builders/racers.
[/quote]

Just finished up a SBC NHRA Super Stock short block today - 4 lbs. breakaway and rotating, 15/50 break in oil on everything
[/quote]

Thats an amazing low number to rotate a short block. Thats a crankshaft, rods and Pistons with rings. That's only 6 in/lb
per cylinder.
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Re: Stock Eliminator secrets?

Post by LSP »

jed wrote: Sat Oct 17, 2020 11:22 am
LSP wrote: Wed Oct 14, 2020 10:43 pm
THE lowest I’ve ever heard on a SBC (8 cylinder of course) was 7 lbs/ft of rotating torque... 1 lbs/ft difference could be error.

THE lowest I’ve ever witnessed was 11-12ish rotating and I’ve been fortunate enough to have been around a lot of very sharp and competent builders/racers.
Just finished up a SBC NHRA Super Stock short block today - 4 lbs. breakaway and rotating, 15/50 break in oil on everything
[/quote]

Thats an amazing low number to rotate a short block. Thats a crankshaft, rods and Pistons with rings. That's only 6 in/lb
per cylinder.
[/quote]

Yes, rotating crank, rods, pistons with rings, cam/belt drive
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Re: Stock Eliminator secrets?

Post by tenxal »

smeg wrote: Fri Oct 16, 2020 7:06 pmThis is a really good thread, keep it going please. How hard are you guys turning these things at the stripe?
My 327-275 (.390/.410 camshaft) will be about 7,400 at the finish line in decent air.
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Re: Stock Eliminator secrets?

Post by Jeff Lee »

My D/S ’70 AMX would go about the same 7400 at the stripe. Best it ran with the Autolite carb was 10.55 @ 125 “back in the day” (like in 2004 or so?).
Car still at chassis shop...tubs finally going in this week. Bad habits die hard!
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Re: Stock Eliminator secrets?

Post by shoedoos »

Tenxal....couple of questions....

1 - why the plastic spacer under the cap screw/bolts in the water pump/front cover photograph a page or two back?

2 - What's the trick to getting a rotating assembly/short block to spin at 8lbs?
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Re: Stock Eliminator secrets?

Post by shoedoos »

smeg
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Re: Stock Eliminator secrets?

Post by smeg »

Thanks, I thought you guys would be geared to turn higher than 7400 sounds like more anyway.
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Re: Stock Eliminator secrets?

Post by 1972ho »

Some turn more rpm a lot of times it depends on the situation heads are bracket racing I shift mine at 7500 and thru the lights at 8100
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Re: Stock Eliminator secrets?

Post by tenxal »

shoedoos wrote: Tue Oct 20, 2020 7:19 pm Tenxal....couple of questions....

1 - why the plastic spacer under the cap screw/bolts in the water pump/front cover photograph a page or two back?

2 - What's the trick to getting a rotating assembly/short block to spin at 8lbs?
1- The plastic spacers are a Steeley-Eyed-Stocker-Secret. :wink: The cap screws were too long, we were headed to the dyno and since there were all these plastic oil pump drive shaft sleeves laying around..... :lol:

2- Honestly, it's not that much of a 'trick', at all. While most of the drag comes from ring tension, piston-to-wall clearance is a big part of it also. Comparing the actual cylinder contact area of a barrel-faced 5/64" (.078) ring to a .9mm (.035) flat faced ring, for example, can be pretty revealing. The oil rings are a big part of the total drag picture. My opinion on oil ring packages runs counter to the mainstream of what most do today. To avoid opening a can of worms, I'll leave it at that. :) Paying attention to perfect alignment of the cam/crank gears/timing chain is another area that very few consider or investigate.

My good pal that builds killer good BBC Stock Eliminator engines routinely sees rotational numbers less than mine and does it with adequate oil control.

And well done Super Stock SBC's are on a whole different planet re: rotational numbers, as LSP has noted. =D>
Last edited by tenxal on Wed Oct 21, 2020 1:44 pm, edited 2 times in total.
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Re: Stock Eliminator secrets?

Post by tenxal »

smeg wrote: Wed Oct 21, 2020 1:09 amThanks, I thought you guys would be geared to turn higher than 7400 sounds like more anyway.
Each engine has it's limiting factor and on mine, it's the intake manifold. While the cam profiles and spring pressures are certainly capable of more rpm, there's no upside to running it past where the limiting factor loses you more than the increased number of power pulses gains you. The trick is to get it to hang on after it peaks without nosing over. :wink:

Other combos with better intakes buzz 'em much harder.
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