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tmdog
11-28-2002, 03:24 PM
NASCAR -- I assume they run small block. How in the world do they wring out massive H.P from those engines. I don't think a trip to the local auto part store for some engine additive would do the trick. Anyone know? JIM

GEOO
11-28-2002, 04:16 PM
$$$,RPM's & don't last long.
My humble SBC makes over 700hp!! Took me three years to get it this way and still working on her. wink

CDMA
11-28-2002, 05:16 PM
And you thought you were getting the "humble" engine back with the boat...hahahaha wink

Chris

Call me dusty....

HyperDonzi
11-28-2002, 07:02 PM
All it takes is $. Notice you dont see many people running that much hp from small blocks because it gets costly. They tear the whole car INCLUDING the entire engine and re do everything so they can go run it wide open for 4 hours all to do it again.

DS88
11-30-2002, 07:26 PM
Even though the NASCAR rule book seems to change on a weekly basis, I think there are a few common denominators that prevail: High compresion, I believe there're up around 12:1 compresion these days burning race gas of course. Big cams: they run flat tappet (solid lifter cams) but their .050 duration numbers are in the 270 -280 degree zone with over .600+ inches of lift. Big intake manifold and heads: They use an extremely tall independent runner intake that has enormous ports that match the equally enormous intake ports on the heads, I'd venture to say the intake on the head is in the 230+cc range with a 2.20+ inch valve. Then to top it off, with the big cam, big heads and race gas they have tuned headers that helps them to scavenge the cylinders. All of this of course leads them to turn upwards of 8500 RPM. I wonder where they'd be if they took the top off the compression ratio limit and allowed them to run roller cams? I think the Busch series cars run roller cams but only have 9:1 compression.

Dave

DS88
11-30-2002, 07:32 PM
And yes, they are normally aspirated small blocks, 358 cu. in. limit. And everyone is correct, they cost large amounts of $$$cash$$$.

Bryan Tuvell 33ZX
11-30-2002, 09:27 PM
Plus they run 2 hours and start fresh, we run a 150 hours and hope for the best! Big difference.
I would have liked to watch more races this season but boating got in the way.
Thanks for the technical data too, interesting.
Bryan

(R RUDD, our neighborhood "boy" from Chesapeake!)

Rootsy
12-01-2002, 01:52 PM
those motors are works of art... precision... and tricks that few of us even know of...

on a different twist, something that truly amazes me sometimes... how do you get an original 255 hp 350 chevy to produce 625 hp???? with STOCK cylinder head castings... although the ports are recontoured but retain original volumes (untouched combustion chambers and valve angles)... stock compression ratio and Original quadrajet carb (blueprinted and balanced, opened up for fuel flow... stock venturis)... yep... 625 hp running the NHRA legal ERC fuel... and when she is warmed up... the pistons DO touch the cylinder heads... wink

BigGrizzly
12-02-2002, 12:23 AM
Let me throw something in here. Compression was 14.7:1 max and they are running rocker ratio of 2.25:1 and run anove 9,000 on short courses and Mark 625 won.t even qualify in NASCAR