HC5A Kart build

[ausjet]

What do you guys recon of the turbo drain hose angle? It’s the best I can do without modifying the mounts to raise the turbo.

[racket]

No good :-(

Unless its in the lowest point of the combustor it'll still allow too much fuel to potentially accumulate , it only takes 50cc of fuel to cause an overspeed

[ausjet]

Oh sorry the hose I’m talking about is the turbo oil drain. It runs downhill to the tank but not sure if the angle is steep enough

[racket]

LOL......my bad :-)

Your lube drain will be OK , I had a very shallow slope on my karts drain jetandturbineowners.proboards.com/attachment/download/46 , probably no more than 100 mm fall over 500 mm , the main thing is that its a continuous downhill slope and that the oil dumps in about the oil level , though with the engine running and generally a fair bit of air/gas bypassing the seal/s theres enough "pressure" to push the lube along , most problems would be when the engine is at low power setting with plenty of oil flow but not much air/gas pressure .

Cheers
John

[ausjet]

The Marco UP10 oil pump arrived in the mail the other day. Had some time today to mount it and the fuel pump up.




The oil cooler mount I made a while ago never looked right to me and got in the way of the inlet/outlet fittings so fabbed up a new one.


Time to start plumbing up the oil and fuel systems. I would really like to control the lot with arduino but I don’t have the electronic or coding experience. So was thinking the tried and tested pwm fuel pump control. Has anyone had success in mounting the control off a kart foot throttle? Or maybe a dial mounted on the steering wheel. The latter sounds like the easier option.

I have an aeromotive bypass boost compensated reg with plans to use it to automatically control oil pressure. I saw someone on here or the yahoo diygt using one. Hopefully it works as well with oil. Ideally I would like to have a base of say 40psi on startup/low idle then ramp up on a 1:1 ratio with a P2 reference. Pump going flat out and relief at 70psi.

Stay safe- stay in the shed 😉

[ausjet]

Oil pump hosing all done, hopefully get some time on Monday to test it out.

[azwood]

I have a big fuel reg controlling my oil pressure I had to drill the port hole to 3.5mm to make it work the benefits are lower start pressure causing less wheel drag then it ramps up same as a EC does

[ausjet]

May 26, 2020 17:11:12 GMT -5 azwood said:

I have a big fuel reg controlling my oil pressure I had to drill the port hole to 3.5mm to make it work the benefits are lower start pressure causing less wheel drag then it ramps up same as a EC does

Oh nice, what reg are you using/ which port did you drill out? I havnt had one apart before, I assume it’s like a standard relief valve with a diaphragm assist on top to increase spring pressure relative to boost? I think the one I have might be too small, I bought it years ago before I knew what flow rates I would have. Good to know I could modify it to suit 👌🏻

[azwood]

Just a cheap eBay job man I drilled out the port to the bottom return line just try it before you drill it go for a big one.

[ausjet]

Gday all, I’ve been thinking about how I’m going to control the variflo nozzle fuel bypass to throttle the engine. Does anyone have any ideas/input as to how to setup a needle valve for a cable actuation from the karts throttle pedal? The problem I’m facing is any sort of needle valve needs like 3-4 full turns within it’s range. The kart foot throttle cable has about an inch of travel. I could try grinding the needle seat to a very blunt taper but before I possibly wreck a perfectly good valve, thought I’d ask first.
It seems a V ball valve would be perfect for this application as they’re a quarter turn valve that can be used for metering (unlike a standard ball valve) but I can’t seem to find any 1/4” or smaller ones.

[racket]

You'll need to find out just how much "metering" of the valve is required on the engine at the pressures being used , you might find that its less than you think .

The simpleist way is to fit the valve into the system and them manually operate it whilst running the engine and noting the position and degree of operation required to produce the full power range from the engine , then you can determine how to obtain that operating range .

The other way will require a few pressure gauges and considerable fiddling around with flow measurements vs pressures vs valve operation

Cheers
John

[ausjet]

Thanks John, I have setup a PWM foot throttle for the pump speed control aswell so I’ll test the bypass throttling like you said once I get it running. See which one produces the best results.
In the mean time, I’ve trimmed the unusually large exhaust outlet off and welded on a 5” v band flange. Was a surprisingly hefty piece of metal being 15mm thick.


And made a dash out of some aluminium offcuts

[ausjet]

Starting to take shape now, front brake kit installed, removed the now useless rear system given the cut axle.
P2, oil temp, oil pressure, egt and volt gauges fitted up, had a crack at making some hard fuel lines which turned out well once I started to consistently remember to put the flare nuts on before flaring the tube 😂 Most of the hosing is done now apart from the throttle- waiting on a needle valve for that.
Sourced a few scuba tanks and a fill whip last weekend so I can set up impingement starting. From reading some of the other posts I think I’ll fit something up in the comp scroll. Does anyone have pics of their setups to draw some inspiration from?

[pitciblackscotland]

G'day Keith,
on my GTC20 engine it has the impingement pipe in front of the comp scroll, looks to be on a sharp angle. Kart looking good sorry can not upload a photo.

Cheers,
Mark.

[racket]

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