new member introduction, also can i get opinion on ignition

[kevin lee]

I had a go at making a Larry

spec stinger.





The head could be a restriction in the intake, its quite large M5

Also the gap may need tightening as its set at .5mm, ill make one with a .3mm gap tonight.

https://www.youtube.com/watch?v=Nk4K0ug ... ata_player

I made small changes too my little rat. I cut 40mm out of cc length. 20mm would have been oin the middle of the old spark plug and I wanted to replace it with a cm6.

I moved the intake too see the effect and lengthened it so it is now 2.7 calibers in length.



https://www.youtube.com/watch?v=AmFmXEE ... ata_player

https://www.youtube.com/watch?v=yb5lyOR ... ata_player

Tonight it'll run fo sho

[kevin lee]

Oh and I came up with a decent plan for throttle, I need to spend time researching because Iam not sure what to buy. But I think that if i only open the bottle tap enough to supply enough fuel for full throttle. Instead of 100% open. I should gain marginally finer control at the ball valve.

I want a new ignition source also, because the battery drill is annoying

[kevin lee]

Last night i made another larry spec stinger using 2 x M5 countersunk screws welded head to head with a .2mm gap instead of the .5mm gap (.5mm gap un tested on an engine). i setup the fuel line and stinger in an adjustable fashion and commenced start up attempts once more.

so as i intended, i only slightly opened the bottle tap too allow enough flow for this small rat jet. I attempted about 3 times to get any kind of buzz out of it but not really getting any where. I could get pops bangs and growls but something was missing. I dont know why but i decided it wasnt getting enough compressed air to get it to lock in. I altered my air gun and then it literally jumped into action and ran like a champ extremely happy!!

I have a 10min video of the entire start up attempts from this evening but i edited it down to the few moments where it jumps into life and warms up. In the video i opened the ball valve right out and then sowly eased in more gas from the bottle tap. it started to get rough at the topend and for some reason i just shut it right off. I should have tried the low range of the throttle and also turned the damn lights out

http://www.youtube.com/watch?v=rFDKkfZA_uw

sounds extremely loud and this was my first experience of the pulses against my body. its kinda weird haha

huge thanks to Joe for the tips and enthusiasm and also thanks to larry (is Larry still about?) for the stinger design it appears to work very well and is a better solution for me than the rosscojector.

[kevin lee]

Pyrojoe i found this needle valve available in the uk for £30 (about $50) is this more suitable than my ball valves?



http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... ink:top:en

Thanks in advance
Kevin

[PyroJoe]

Thats running nicely, The ball valves are great for emergency shut-offs. Maybe if the handle was very long, 12 to 18 inches it would have better control. I find multiple needle valves in parallel give reasonable results. They can be the less expensive type, just need to make sure they have the fine thread on the needle stem and can handle the pressure. My apologies for the late response, was off line this weekend.

[kevin lee]

Thats running nicely, The ball valves are great for emergency shut-offs. Maybe if the handle was very long, 12 to 18 inches it would have better control. I find multiple needle valves in parallel give reasonable results. They can be the less expensive type, just need to make sure they have the fine thread on the needle stem and can handle the pressure. My apologies for the late response, was off line this weekend.

No worries and thanks mate, I was happy when it fired up. I ran it again for longer and more gas, it was a bit funny starting though. Had to get it running with compressed air until it was glowing then it sustained.

I will look more into fine control of the gas flow.

However the noise of this latest engine is a problem. I need to find a test zone that is away from my house and other peoples houses. Its a shame the UK is so over crowded