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Performance, Brainstorming & Tuning Talk about modifications, or anything else associated with performance enhancements. Have a new idea for performance/reliability? Post it here. No idea is stupid! (please use Detailing and Appearance for cosmetic ideas)

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Old 03-01-2006, 02:31 AM   #41
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Hence my request in the want ads for a bunch of manifolds, I too have access to flowbench facilites. There will also be performance folks on the other side of the world doing precisely the same thing on manifolds I am sending on their behalf.

We also see what you see, but do not necessarily agree that internal volume changes and/or rework will result in significantly greater flow-rates at the meters/sec of airflow (overall) that this engine is capable of while being supercharged (NA is a different story). With a few manifolds, heads, and superchargers we will be able to go past the point of reasonable returns, then back up.

However we may not even bother (and suspend any real work on a flowbench) if what we have seen continues; after observing the pressure gradients across the entire intake tract by turning the SC with intake and heads mounted (off the engine - on the bench) with a 3phase electric motor on 220VAC (we drilled various access points along the intake tract top and bottom to insert probes). The lower pressure areas, which mean higher rate of localized flow (which means higher restrictive force in that area) are being mapped at various valve openings. So far incrementaly larger valve openings has resulted in the greatest rate of flow increase....with negligeable changes in pressure gradients over the rest of the intake tract.

In other words, physical gains to be had in a "pressurized" intake tract may make finding them pale in comparison to simply freeing up breathing with either rockers or a camshaft change. And given the preliminary results showing lack of gradient changes infers that temperature increases due to local obstructions within the intake tract are minor enough that proper application of water injection to enhance the adiabatic rate might be the final piece that keeps the KR monster at bay.

We thought about attempting to restrict flow to raise atmospheric, then introduce atomization to determine the best nozzle I.D. and head pressure, but have ruled out the accuracy. We will have to use the real thing unfortunately...

Time will definitely tell, I suggest we continue to compare notes

p.*. another we are measuring (indirectly) is the amount of HP required to drive the SC by measuring motor flux. This could also generate more aggregate HP if we can reduce the power required to create that pressure gradient in the first place...
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Old 03-01-2006, 09:30 AM   #42
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There'* not alot you can do to decrease the amount of power it takes to turn the SC for a given amount of output power. You CAN keep it running cooler, though, so the same amount of compression gives you greater power.

As far as manifolds go, the Aussies have quite a different setup. And you need to remember that my GOAL this time around is to improve flow and performance as much as possible WITHOUT removing the heads or valvetrain, and in a sense, I've already proven it can be done far beyond anything we've seen before.

Some of what is going on out West here that you don't understand (or agree with) with regards to the LIM is very hard to understand without us releasing key details. Let'* just leave it at the fact that someone figured out how to increase port velocity in our intakes while slightly restricting volume. The method used prevents pressure build in dead areas of the manifold.

When you get into boost, it takes time to build boost in the manifold to the point where the air will efficiently run to the valves at the proper velocity. Decrease that time and increase the velocity and you have a winner.
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Old 03-01-2006, 03:38 PM   #43
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Quote:
We also see what you see, but do not necessarily agree that internal volume changes and/or rework will result in significantly greater flow-rates at the meters/sec of airflow (overall) that this engine is capable of while being supercharged (NA is a different story).
Why not? The behavior of the internal volume of the plenum has a lot to do with the filling of the cylinder. To give you something to think about, in a NA race Buick V-6 engine, the booster signal is stronger with a Holley 1050 CFM Dominator than in a Chevy V-8 race engine. The V-6 intake has less volume than the V-8 intake. The same applies to boosted engines.

Quote:
The lower pressure areas, which mean higher rate of localized flow (which means higher restrictive force in that area) are being mapped at various valve openings. So far incrementaly larger valve openings has resulted in the greatest rate of flow increase....with negligeable changes in pressure gradients over the rest of the intake tract.
Sorry to crash your party...the boost is not constant all the time and yes, the more you open the valve, the more flow you will show; just like opening a water faucet. However, have you taken into consideration the velocity? I could care less about big flow numbers; my main concern is velocity versus distribution and at the end, how well you utilize and burn the mixture. In a nutshell, is not the amount of the air you flow, but the quality that makes the power.

A close friend of mine used to race a 1980 Pontiac TA with the Turbo 301 engine. The rules require OEM parts, including heads, intake, carburetor, valve size (1.72" intake, 1.50" exhaust), stock cam lift (0.344"). The intake on these engines is completely flat. Just by doing allowed modifications for the class, specifically on the cylinder heads, exhaust and intake, he held the record in it'* class at 12.39 @ 103.67 MPH in the 1/4 mile. The car weght was 3800 lbs with a stall of 3,200 rpms and 4.10 gears.
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Old 03-01-2006, 06:28 PM   #44
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Quote:
Originally Posted by ssei1995
Quote:
We also see what you see, but do not necessarily agree that internal volume changes and/or rework will result in significantly greater flow-rates at the meters/sec of airflow (overall) that this engine is capable of while being supercharged (NA is a different story).
Why not? The behavior of the internal volume of the plenum has a lot to do with the filling of the cylinder. To give you something to think about, in a NA race Buick V-6 engine, the booster signal is stronger with a Holley 1050 CFM Dominator than in a Chevy V-8 race engine. The V-6 intake has less volume than the V-8 intake. The same applies to boosted engines.

I'm not sure how you can adequately compare the two. There are significant differences between pushing and pulling air to the combustion chamber, therefore comparisons to NA work are barely valid. All I'm hearing is that the velocity of the air going through the carb is greater than on the V8, creating higher fdility at the carb...so what? Are you saying that decreasing intake tract I.D. is a good thing?

Quote:
The lower pressure areas, which mean higher rate of localized flow (which means higher restrictive force in that area) are being mapped at various valve openings. So far incrementaly larger valve openings has resulted in the greatest rate of flow increase....with negligeable changes in pressure gradients over the rest of the intake tract.
Sorry to crash your party...the boost is not constant all the time and yes, the more you open the valve, the more flow you will show; just like opening a water faucet. However, have you taken into consideration the velocity? I could care less about big flow numbers; my main concern is velocity versus distribution and at the end, how well you utilize and burn the mixture. In a nutshell, is not the amount of the air you flow, but the quality that makes the power.

A close friend of mine used to race a 1980 Pontiac TA with the Turbo 301 engine. The rules require OEM parts, including heads, intake, carburetor, valve size (1.72" intake, 1.50" exhaust), stock cam lift (0.344"). The intake on these engines is completely flat. Just by doing allowed modifications for the class, specifically on the cylinder heads, exhaust and intake, he held the record in it'* class at 12.39 @ 103.67 MPH in the 1/4 mile. The car weght was 3800 lbs with a stall of 3,200 rpms and 4.10 gears.
Where did I reference boost pressure? If anything I would like to see lower boost pressure. Velocity means nothing, especially if it can be shown that the length of tract in question experiences relatively few pressure difference from start to finish. In fact I would like to see a pressure drop the closer it gets to the valve (not based on minor tract length either).

You need to go back re-read what I wrote;

"because" we see little variation in pressure at various measuring points while pushing air through the ENTIRE intake tract (no matter what valve opening position, this means (directly) that the velocity is fairly constant. This is relevant up to a point where the SC can not safely spin higher. At this point in time we feel comfortable that the intake path is does not possess areas that need rework to reduce/rework physical obstructions up to engine redline. utilizing smaller pulleys.

The act of measuring this flow in actua assembedl S1 parts makes it clear that volumetric gains through reworking the tract configuration are minor compared to just opening up the valve more. The amount of work to get to this conclusion has taken close to 20 hours, I suggest quite a bit less time than attempting the finds gains by reworking the tract itself.

I admire Wilwren for sticking to a path that only looks at modifying the OEM parts.

However if opening the valve allows the same level of performance increase and I have not had to spend x number of hours reworking the internals of those OEM parts to realize the same gains, I sugges that is just as relevant.

For me, my path usually leads to significant gains, and more importantly repeatablility. The added bonus...there is no "ambiguity" about what has occured to achieve the measured results. A dyno IS your friend in this case....
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Old 03-01-2006, 09:17 PM   #45
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Well, we can go pages on the subject and disagree in many of the findings. Like you, I have the same setup with a supercharger, LIM and cylinder head, also driven by an electrical motor. I am using a SuperFlow SF-600 flow bench. The flow bench has the Audie Technology ProFlow software/data acquisition and also using the Audie Technology Swirl Meter that allows me to map the behavior of the LIM. I am not done with the testing since I am digesting the data and consulting with some friends. The data is based on before and after the changes done to the LIM.
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Old 03-01-2006, 10:46 PM   #46
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Any disbelievers in the idea of higher port velocity should take a good hard look at how an engine works and what the benfits of that velocity are with regards to in-cylinder combustion effects. Power and efficiency will both benefit. Funny how so many cars over the years have worked to improve port velocity and the result is more power and efficiency, while being able to lean carb jets or reduce injector DC.

If you don't care to take the time to understand what'* being discussed here, go your way and see what you can come up with. You'll improve what you started with, but it may not reach it'* fullest potential.
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Old 03-02-2006, 01:08 AM   #47
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Just so I'm clear on this higher port velocity thing, as it relates "directly" to forced induction, what gains have you seen?

More to the point, where precisely have you measured an increase in fuel/air velocity?
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Old 03-02-2006, 01:35 AM   #48
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Quote:
Originally Posted by Sukhoi
Just so I'm clear on this higher port velocity thing, as it relates "directly" to forced induction, what gains have you seen?

More to the point, where precisely have you measured an increase in fuel/air velocity?
As already stated earlier in this topic, I don't have the liberty to discuss the numbers, as the data doesn't belong to me. When the owner of that data feels he'd like to share it, he will.

Most people that come up with a solution to a problem like to make sure it'* the RIGHT and BEST solution before saying 'hey, loook what I found, you should try this".
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Old 03-02-2006, 02:25 PM   #49
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IWhich throttle body do you use when you swapped in the 94/95 supercharger?
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Old 03-02-2006, 02:29 PM   #50
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The only one that fits and works properly with the flow. The 94/95 TB.
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