Improving low valve lift flow

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You’ll have to send in the converter to be done for you.
Anything off the shelf is just dicey IMO, or more specifically, for me. I’ve been a manual trans guy for decades. When it came time for a converter, I had my first two custom made.

You know the drill! Give them every last tie but if information and what you want out of the car and they’ll set you up.
 
rumblefish360 said:
You’ll have to send in the converter to be done for you.
Anything off the shelf is just dicey IMO, or more specifically, for me. I’ve been a manual trans guy for decades. When it came time for a converter, I had my first two custom made.

You know the drill! Give them every last tie but if information and what you want out of the car and they’ll set you up.
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Well when I first pulled it off the 360, and then decided to do the 340, I sent it to Tampa torque Converter/ American Racing converter (just to cut it open for inspection)the shop foreman said he felt bad to even charge me, because all he did was replace one slightly worn thrust washer, but, you got to get the owner paid... you know speaking of, I never got any paperwork on that, I wonder if he paid himself on that one? In retrospect it almost sounds like it!
 
Low lift flow means different things in different applications but for about 70% of us, maybe more, it's .100-.400" valve lift.
With a 2.02
We really want to see like high 60's-to 70'scfm @.100. , mid 130's-140's at .200 high 190's to [email protected] and so on..240's @.400 lift. In the realm of a 178-180's cc intake port.
 
fishmens67 said:
A bigger intake valve will increase low lift flows, with minimal porting peak flow will occur at a lower lift.
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What's the direction of flow with a large valve curtain area and very little piston demand all the while the exhaust gasses are looking for somewhere to go?

Put another way what's the piston speed around the overlap period to create the demand for it to flow in the first place?
 
Hysteric said:
What's the direction of flow with a large valve curtain area and very little piston demand all the while the exhaust gasses are looking for somewhere to go?

Put another way what's the piston speed around the overlap period to create the demand for it to flow in the first place?
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DAMMIT! You are on a ROLL. Damn good questions. All important stuff.
 
Dan the man said:
What the formula for calculating this?
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Valve diameter times .25 gives you the L/D ratio at THAT particular ratio.

There are other ratios I use to determine lift. For SFT I use .31 L/D ratio. I can’t always get that much lift due to valve train limitations and what you can actually get on the lobe.

For example, I have a 2.055 valve so multiply that by .31 and that’s .637. The closest I could get was .620 lift and have a reasonable lobe.
 
Hysteric said:
What's the direction of flow with a large valve curtain area and very little piston demand all the while the exhaust gasses are looking for somewhere to go?

Put another way what's the piston speed around the overlap period to create the demand for it to flow in the first place?
Click to expand...
The op asked a generic question I gave a generic answer.
When talking reversion there are many things to consider valve timing , exhaust, intake type, on and on.
Is reversion a problem with a stock engine? stock cylinder head?
 
fishmens67 said:
The op asked a generic question I gave a generic answer.
When talking reversion there are many things to consider valve timing , exhaust, intake type, on and on.
Is reversion a problem with a stock engine? stock cylinder head?
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The generic question was asked from the perspective of low lift flow from what a flow bench tells you you would have not from what actually happens in a running engine. Agreed there are many variables that contribute to reversion but viewing flow from the perspective of a flow bench as a opposed to what actually happens in a running engine is flawed.

Concerning a stock engine and reversion why do they sell throttle body cleaner? Ever pull the air cleaner lid of your engine and wonder how that black stuff got deposited on the underside? That's how far reversion goes all the way past the carb. People think flow is only one way its not and the bigger you make everything in regards to valve, port, intake and carb the worse it is at low running speeds.
 
a cylinder head is like a women lol, the first inch of the bowl is the most important, that and the valve job.
 
Throttle body cleaner?
How many engines have an oil breather to the intake. All. Yeah we're Factory designing reversion into our engines, that's what we're doing, no.
 
MOPAROFFICIAL said:
Throttle body cleaner?
How many engines have an oil breather to the intake. All. Yeah we're Factory designing reversion into our engines, that's what we're doing, no.
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That's funny my oil breather is connected to the underside of the throttle plate. So where's all that carbon deposited on the underside of the air cleaner coming from.........You know DIRECTLY ABOVE THE CARB?
 
Jon Kaase Uses Finger to Test Airflow

Notice the flow goes both ways........LOL wonder when that happens.

Here's something else you didn't figure on, looking at the pressure pulse at the top of the runner it was weaker also that large plenum dampens the pulse because the air/fuel mixture has weight and the exhaust gasses have to get past it. Notice all that fuel on the walls of the manifold build up at WOT, well what's putting it there? Notice how it pulses?

Now go place injectors just before the intake valve or in the port and ask yourself what happens when the injector isn't cycling what is there to dampen the exhaust pulse heading back up the runner during the overlap period?

A flow bench will tell you nothing about what actually happens in a running engine.
 
Hysteric said:
That's funny my oil breather is connected to the underside of the throttle plate. So where's all that carbon deposited on the underside of the air cleaner coming from.........You know DIRECTLY ABOVE THE CARB?
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Must be the dust you eat when the kangaroos outrun ya , mate. lol
 
Hysteric said:
Jon Kaase Uses Finger to Test Airflow

Notice the flow goes both ways........LOL wonder when that happens.

Here's something else you didn't figure on, looking at the pressure pulse at the top of the runner it was weaker also that large plenum dampens the pulse because the air/fuel mixture has weight and the exhaust gasses have to get past it. Notice all that fuel on the walls of the manifold build up at WOT, well what's putting it there? Notice how it pulses?

Now go place injectors just before the intake valve or in the port and ask yourself what happens when the injector isn't cycling what is there to dampen the exhaust pulse heading back up the runner during the overlap period?

A flow bench will tell you nothing about what actually happens in a running engine.
Click to expand...
Lol @ hysterics insecurity!
No ****!Not the complete picture!
That's why we dont build engines entirely with flow benches! Show us what you do or take your rope and piss up it somewhere else!
 
MOPAROFFICIAL said:
Lol @ hysterics insecurity!
No ****!Not the complete picture!
That's why we dont build engines entirely with flow benches! Show us what you do or take your rope and piss up it somewhere else!
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And.......
 
Dan the man said:
Are bigger intake valve's better for low lift flow? 3 angel, or 5 angel valve job? Just asking, trying to learn
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Oh, You'll definitely need the 5 angels, with their help You may actually buy an A-body Mopar yet!!!
 
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