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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 6:35 pm 
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Posts: 63
Quote:
Personally I'd just put one of them on (M1 or modern eq)and concentrate on other things like how to build the engine with good seal and strong bores and experiment with the cams to find what works best etc.


Ive got an M1 and 7 other manifolds to try. Also bought my own torque plate because my machinist didnt have 1.

Quote:
Personally I would spend the money first on getting a port job that has the right velocity profiles everywhere in the port, with no turbulence or chokes upstream from the valve and no fuel separation issues. The motor starts at the heads.


Im building a PTS flow bench to achieve this.

Quote:
Ok so you chase the ultimate plenum then what carby do you put on it, how do you line up the barrels for optimum feeding into the plenum huh?


Ive got numerous holleys and Carters i want to try as well as webers.Im hoping you might be able to shed some light on the topic of how these different aspect relate.

Hysteric


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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 7:53 pm 
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Well it sounds like your a determined experimenter.
As to the subject of carby to plenum interaction, make sure the flow from the carby is even velocity across the plenum opening as velocity differences effects the entry to the runners.
Use a pitot probe. Get yourself a gas bench to help tuning the cylinder with. Sample each cylinder individually.


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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 8:31 pm 
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Get yourself a gas bench to help tuning the cylinder with


Yeh thats on the list too but they're not cheap!

Hysteric


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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 8:37 pm 
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If your serious about experimenting and tuning to perfection you cannot do it without a gas bench. I wouldnt spend money on a Wide band setup as a first purchase. You may need one later but nothing, absolutely nothing, replaces a 5 gas bench. They take a lot of smarts to understand the connotations and combinations that can cause whatever your seeing on it but they are amazing tools to have.


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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 10:49 pm 
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I also have a DL-32 with 2 x O2's and 2 EGT's to start with.

Whats the cheapest 5 gas bench on the market at the moment?

Hysteric


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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 11:11 pm 
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I dont know whats cheapest but what I do know is either buy a bench with modern ANDROS internals or get a bench from Bridge Analyzers. Bridge make their own stuff, Bob Schrader is a very smart man, good to talk to, it would be worth your while emailing him.
The Andros option is Andros make the gas bench stuff for just about every other manufacturer around. Becnhes like the old SUN machines are Andros. The old stuff is large circuit boards and many computer boards etc that you add to a CPU box, it works excellently but its very expensive to fix. I have a new style its a compact unit that data logs to a laptop, the old ones dont do that. The new ones NEVER need calibrating, the old ones you have to run calibration gas through them every few months and the gas is mega expensive like $1200 a bottle. The modern ones are the way to go. And they warm up in 20 seconds, the old ones take 20 minutes.

There is a manufacturer in Australia, called CODA. check them out too I think they use a version of Andros internals but not sure. . Mate of mine has one of their machines, its good but its more complex with operation than the Andros. The coda bench has RPM logging and some scope functions too so its a pretty good deal.
My bench is a Lucas, its simple and reliable. portable, and uses common filters. Some of the portable ones use too small a filter and there a pain.

Dont get a hand held one, there toys. Filter too small, pump inadequate, water traps too small. A proper machine can run all day all week.


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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 11:27 pm 
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You mean this one:

http://www.autotestsys.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=ATS&Product_Code=BRI9005&Category_Code=EAAA

Not as dear as i first expected.

Hysteric


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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 11:34 pm 
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Yeah that would do the job but check if it outputs to a PC for logging and recording of the driving around in the car etc.


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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 11:44 pm 
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So i can run this thing in the car while im at the strip or circuit?

Hysteric


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 Post subject: Re: Webers on a......
 Post Posted: Fri Jun 01, 2012 11:57 pm 
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yep drive the car with it recording is the way to go. free dyno =; Make sure it does that to a laptop or some other means. My bench gets driven around a lot.


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 Post subject: Re: Webers on a......
 Post Posted: Sat Jun 02, 2012 12:30 am 
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Wow......Seems like the ultimate data logger+tuning tool in one............s**t wish i new this earlier I would of just sprung for this first.

Hysteric.


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 Post subject: Re: Webers on a......
 Post Posted: Sat Jun 02, 2012 12:41 am 
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If your going to chase combustion efficiency you need a gas bench. A wideband does not show efficiency it only shows AFR. Gas benches display the gas species and percentages etc. Far more useful than just AFR. If you going to run hot cams you must see the unused O2 concentration and the balance of carbon gases. WB's are hopeless when the engine is inefficient and pumping out O2 and lots of CO. To do proper tuning you have to see how much fuel energy is being used inefficiently and correlate it to power output etc. Many engines make lots of power but they are actually poorly performing. There is only one perfect engine we just havent got it yet.


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 Post subject: Re: Webers on a......
 Post Posted: Sat Jun 02, 2012 1:29 am 
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Quote:
WB's are hopeless when the engine is inefficient and pumping out O2 and lots of CO.


OK......What if the initial set up "IS" to a certain extent efficient. One of my main reasons for being here is the realization that an engine isnt just an "Air Pump" but as you say:
Quote:
The way to view engines is this, they are not just an air pump, they are a machine to raise the energy level of liquid fuel to the state of combustion. What that sentence means is the primary function of an engine is to burn fuel. To do that the fuel has to be turned into a gas, to so that the fuel has to have its energy level raised to boiling point


If i can from the start build an engine that is the most(with in reason) efficient to begin with then is it possible to use a WB to fine tune and get that extra improvement or is a gas bench still a requirement. In other words if the Integrated machine concept is applied to every aspect of the build ie carb-intake-heads-compression-cam and has been designed and built with true "integration" as the ultimate goal am i still leaving alot more on the table performance wise?

man i need another coffee

Hysteric


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 Post subject: Re: Webers on a......
 Post Posted: Sat Jun 02, 2012 5:53 am 
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The physics factors that makes an efficient engine is homogenization and vaporization. Some of the things that occur in hotrod engines go against you achieving that. The first thing to talk about is the actual time period of compressing the mixture is critical to the vaporization level. Its important to have the time combined with the rate and level of compression optimized for the fuel. Nothing more complex than that.
The homogenization problem is controlled by the porting and the carburetion and the squish.
Both these physics problems can be seen only on a gas bench and to another extent on a scope.
The way to start working out this stuff is to put together an engine thats not radical. Something like a 200 degree intake duration is plenty to pep an engine up and allow learning to occur. Now your probably going to think thats a stupidly small nearly stock camshaft, but I tell you it will make impressive power for what it is once you understand combustion gas control.
If you just jump in to a 245 or bigger cam straight away you not going to learn the right things. If you want to learn what efficiency is crawl before you walk.
Hotrod engines are not efficient. period.
A Wideband like Innovates stuff will be accurate information on AFR but AFR by itself is useless to an engine efficiency developer, it doesnt matter at what power level your building the engine the WB is useless for combustion efficiency research. Ive worked with other brands of WB's and Ive had them tell me absolutely stupid information. The others are all junk when your presented with an engine that has wierd problems.
If you want to become a combustion expert get a gas bench for a starter.


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 Post subject: Re: Webers on a......
 Post Posted: Sat Jun 02, 2012 7:27 pm 
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Man i just wrote a whole page then submitted it and was asked to re-login...

Ok for the second time.

Quote:
The first thing to talk about is the actual time period of compressing the mixture is critical to the vaporization level. Its important to have the time combined with the rate and level of compression optimized for the fuel. Nothing more complex than that

Let me brake this down:

Is time AND ENOUGH COMPRESSION critical?
Is this not RPM dependant as rpm rises so fill time diminishes and does not carb function become critical in this process as the carb transits from 1 circuit to the next?

Quote:
The homogenization problem is controlled by the porting and the carburetion and the squish


Simplified...
Porting: Controlling air speed and preventing air/fuel seperation
Carb: correctly sized and set up with good atomization and distribution.
Squish: Creating an efficient enviroment for the mixture to burn. Im sure compression plays a part here too.(Heat/Vapourization)

I was looking to start with a cam with 228 @ .50 for my build.

Hysteric


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