The Jalopy Journal
Discussion in 'Traditional Hot Rods' started by Royalshifter, Dec 12, 2007.
Goose found out Barracudas don't fly well.
Well.......that one did fly, just didn't do so well on the the landing
The return to earth may hurt a little bit I'd think.
Another creation from the fertile mind of cam grinder Chet Herbert. Originally running twin Olds F-85 injected 215 inch aluminum blocks he later went with 4-71 blowers. Chet came up with the unique drive spinning both blowers.
Pretty sure the Jack's Auto Parts Twin had blower drive deal before Chet.
Well there ya go, it shows there’s nothing new under the sun.
The Freight Train way.
now that is slick!!
One of the greatest bait and switches in DRAG RACING. Mr Floyd Lippencot!!!
I kinda wonder if they made those 2 sing like a 16 cylinder engine or had 2 cylinders firing at the same time....
Two at a time for the Train - Chet Herbert tried the V 16 method.
One thing about using a dual-timing chain to connect the front engine to the rear engine is that's very easy to change the firing sequence between engines. You can make the #1 cylinder on both engines to fire at the same time, or any firing order in between. On Chet's dyno, we ran both engines from the "Pulsator" AA/FD together many times, and tried several different firing orders. There was no HP difference.
The dynamics of in-line dual engine dragsters can really give you a headache. Take the crankshaft, for instance, of a V8 engine. The load on the crankshaft in the front of the engine (the front two cylinders) is much less than the load at the rear of the crank, (where the torque load on the crank is from all the cylinders). The torque increases from the front of the crank to the rear, assuming that the engine is under a load (as on an engine dyno or on a dragster going down the track). You might have to let that sink in for a minute.
When you attach two cranks together in-line, (techincally a V16) the load on the crank in the rear engine is both the torque loaded on it from the front engine, plus the torque load on the crank at the rear from the rear engine. Let me say it this way, you had better have a VERY stout crankshaft on the rear engine, because the rear engine is going to have to absorb double the torque on it than the crank of the front engine.
The inline engines that we were using on the Pulsator were bored and stroked 327 Chevys (364 cubic inches each). We were running straight nitro out of the can. If we had been using the newer 350 Small Block Chevy engines, we would most likely not had the issues we had, but the 350's were not available yet. The 350 cranks had larger journals than the 327's. What was happening was that the amount of torque was rattling the rear crank to hell and gone.
Now, scroll up and look at the photo of the Freight Train above. Both the Train and the Pulsator were just about twins of each other (and Muravez drove both cars), except the Train was supercharged on gaoline, and the Pulsator was injected on fuel. Note that on the Train (at that time), the front engine drove both superchargers. We figured that a 6-71 blower with a lot of boost would take about 175 to 200 HP to drive. A blown SB Chevy on gasoline could make about 500 to 550 HP, and it took about 200 HP to drive the blower. Now, if the front engine had to drive both blowers, that meant it took 400 HP, and since the front engine could only make 550 HP, it was only putting 150 HP into the crank on the rear engine, PLUS, that big rubber timing belt spinning the blowers was a beautiful "harmonic dampner". Of course, what the front engine lost in HP driving both blowers, the rear engine made up for by getting the boost from a blower it did not have to drive, so things equaled out.
I feel a headache coming on...
Yes, but these are the things most people never think about...
My good friend and mentor ran a triple engine pulling tractor, he built a out of the hole engine a mid rage engine and a top end engine, said the engines work in there RPM but never pulled down the other.
I see where your headache comes from.
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Some years back I know of a guy (Mike Sullivan & Steve Haight of "Fuel Altered fame) that put two NITRO powered Buick V-6 engines together in a dragster.
As above, no matter how they were connected, what crankshaft phasing or who built the crankshaft connector, they ALWAYS broke them. They tried the big tractor builder guys, didn't work. They even had other chassis builders check the alignment, they stiffened the chassis around the engines, nothing worked.
Yeah, they finally gave up.
Good info. Never considered the loads as you described. Thanks for the detailed information.
Great picture. Looks like Indy, maybe "64" ?
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