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Reminds me of the SBC powered corvette with 8 tall stack injectors sticking out of the hood. It had red rubber balls poked in the stacks. Yup, stared it without removing the balls, sucked them all down to the throttle plates.
 

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Discussion Starter #83
I was pitted next to a guy that ran a 4 cylinder at a race. He couldn't get it started, put way too much fuel in it. About the 5 time he tried, it back fired, and split the fabbed manifold in half. It had a dominator on it and it landed about 2 stalls over. Now days you see burst panels in them, but he didn't have one. It was ugly.
 

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If I remember right you take the square root of 60/28 times the flow at 28" will give you the 60" numbers.
square root of (60/28) x 265 = 388 cfm if and when the port is under that depression on the bench or in a running engine and if the flow/port dose not go turbulent. Just rough numbers that the engine may or may not see.
 

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With rocker ratios at 1.9-2.0 im guessing the valve is chasing the piston away from tdc to get things rolling.
I would love to hear what that dyno pull sounded like. Thanks for sharing this stuff

Chris
 

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Reminds me of the SBC powered corvette with 8 tall stack injectors sticking out of the hood. It had red rubber balls poked in the stacks. Yup, stared it without removing the balls, sucked them all down to the throttle plates.
I guess an engine "sucks" less when it's unrestricted, lol.
 

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Discussion Starter #88
Well the 300-25 with and without the ears was an epic failure. Going back to the Victor E and then in the car to make some test runs.

A friend and I are building a legal Super Stock engine and then going to dyno the piss out of it. Only way I'm going to get it right (er)..
 

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Bummer. Now what do you do with the 300-25? Keep it on hand in case another project comes along that might like it?
 

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I guess an engine "sucks" less when it's unrestricted, lol.
I guess even though volume is not huge, the air doesn't have to change direction as much. I don't have the terminology to describe what I'm thinking. So here it goes..

If it does "suck", and with the camshaft rules or head rules or whatever, the straightened path that the epoxied port in the pics above, dont allow there to be as great of a deperession below the intake valve during intake events. The flow curve(accelerated volume?) continues to accelerate, through piston mid stroke (peak piston speed) So in a sence were trying to get the air column to accelerate at the same speed as the piston? I know its cylinder filling, im trying to wrap my head around what the air is doing. As in how does this "package" work.

Like looking at a 302 ford and visualsing that the intake valve is closer to the carb throats centerline versus a 351. I knw about the deck heights and the other differences. But we hear about short rod long rod engines and stuff, but is it really simpler than that? Offset dowels and angle milling heads were/are done for a reason.

Any other thoughts? Am I way off here?

Chris
 

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I guess even though volume is not huge, the air doesn't have to change direction as much. I don't have the terminology to describe what I'm thinking. So here it goes..

If it does "suck", and with the camshaft rules or head rules or whatever, the straightened path that the epoxied port in the pics above, dont allow there to be as great of a deperession below the intake valve during intake events. The flow curve(accelerated volume?) continues to accelerate, through piston mid stroke (peak piston speed) So in a sence were trying to get the air column to accelerate at the same speed as the piston? I know its cylinder filling, im trying to wrap my head around what the air is doing. As in how does this "package" work.

Like looking at a 302 ford and visualsing that the intake valve is closer to the carb throats centerline versus a 351. I knw about the deck heights and the other differences. But we hear about short rod long rod engines and stuff, but is it really simpler than that? Offset dowels and angle milling heads were/are done for a reason.

Any other thoughts? Am I way off here?

Chris
Offset dowels are usually to give the intake valve a little more clearance to the cly wall and the angle milling usually was to reduce the combustion chamber volume with a side benefit of a lower valve angle.

Your goal is to have at least atmosphere pressure in the cyl before the intake valve closes, so you have to look at the cyl cfm demand compared to the port cfm flow, the closer you can get the two the less the engine will "suck" and the fewer pumping loses you'll have. The valve seat throat will only flow so many cfm , so now you have to have a port that will supply at least that much cfm to the throat minus any losses you have for expansion around the valve and into the chamber/cyl.
 
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