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Home built engine dyno,

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Here is a few photos of my how built engine dyno, used a Ebby current retarder off a truck and the majority of the controls I am getting from a company here in Australia, web site like attached. The idea is that it will take over 1,000 hp engine and also be able to test a engine running at above 10,000. Because I am a Subaru NA nut the only way to get power is to rev the hell out of the engine. My personal feeling is that there is heaps of experienced people capable of building hi power turbo Subaru engine but very few people that can built a high HP NA one. So in my attempt to sort through what works and what doesn't I need a dyno. My biggest bug bear is that you hear a guy say they are changing the rods and putting stronger pistons in and expect more power, or even change the cam. Most of that won't get more power, most NA engines can't develop more then 120nm of torque per litre no matter what you do so. NA is all about hold torque and up the revs, air in more fuel, lower duty cycle and exhaust out which give HP at higher revs.

I also have a build thread on this web site as well as the race car, etc

http://www.ozclubbies.com.au/index.php?/topic/7924-building-and-programing-an-engine-dyno/page-6

Link to the dyno parts supplier,

http://www.dtec.net.au/

Here are a couple of photos plus link to a test run last weekend,

https://www.youtube.com/watch?v=oLd9bMRMk18

Attached Files

That is pretty cool.

What's your theories on what will and won't work on the svx engine?

Hi Chris,

I am a nut case on measuring things, so the I used a pressure transducer in the inlet manifold of one of the cylinders logged the vacuum at 1,mhz. SO got the detail of the air pulses as the valve closed etc also did it from 1,000 rpm to 6,000. Showed clearly that everything before was causing the vacuum to go through the roof into serious negative territory. I have attach a image of the wave pattern.

Okay my goal is 450 engine hp from a 3.3l engine, need,

Injectors of 1,000 cc so I can stay sequential at high rev's,

Twin exhaust pipes 2.5 inch each,

12:1 compression on 98 octane fuel,

Change inlet tract to engine so as I can best use the pressure pulses I can now measure.

Being a Subaru, large bore short stroke the vales are pretty big I also have increased the lift by 1.5mm already and extended the opening times.

Attached Files

I'll be keeping an eye on this, it's going to be good to see it develop and dis/prove your theories

Hi Chris,

I run and posting about the dyno, the Subaru open wheeler engine development, my race car and a few other project on this web site. You need to register

http://www.ozclubbies.com.au/index.php?/topic/7924-building-and-programing-an-engine-dyno/page-9#entry251327

What kind of data are you expecting to get from the pressure transducer. At 6000 rpm you wonder if the sampling rate is fast enough to capture anything useful in relation to valve events.

Nevermind I see 1Mhz sampling

Kelly you would be surprised even at lower rate if you hold the engine speed constant then you can get a range of pressure reading which you can get a understanding of what is happening in the intake.

Biggest issue is were you log.