machining a needle valve assembly

I have a lathe and other machine shop tools, having apprenticed in the trade at one time. I need c/l NVAs in quantity and wondered if anybody has a drawing of the universal c/l NVA they used to sell years ago - or maybe a diagram of a engine manufacturer's example. I made a drawing today that would probably be ok, but maybe guys have saved something that they could send me. Maybe you know a place that sells NVAs that work in any engine. Thanks, Brian P.

Our Host, Leonard Neuman has what you seek. ST Clones, Nelson/PA, etc. http://www.clstunt.com/ Good service, good prices. RSM and Brodak should also be able to provide what you need. Steve

Well the ST NV seems to be about as universal as any. I suppose you could copy any one you wanted (ST, OS, whatever).

The ST may be kinda universal, but it sucks big time when trying to get a setting to stay and then locking the needle. I prefer something like the regular OS Max type with spring ratcheting to maintain the setting. Twice at Huntersville I had the needle move to too lean on me. I hate inverted landings on a dead engine. There had got to be a better way to lock the needle and yet allow some tuning. Lots of threads like the ST is nice, but keeping it form moving can be a bit frustrating.

On the ones I have made (count on two hands!), I have gone to a compression washer system rather than the normal ST way of simply using the locking nut to squeeze the split spraybar around the needle. I just turn a thin plastic cylinder (more like a thinwall tube) piece which slips over the needle, but goes inside the locking nut. Slitting this plastic piece makes it easy to slip over the theaded part of the needle and to compress (thanks Al for the hint) when you crank on the locking nut. The plastic seems to keep the needle from moving around. Anyway this works best for my limited machining skills!

Sorry for sounding a little confused. Made this a few months ago and am trying to remember exactly what I did!

Ty, you need to try the Randy Aero/PA/Nelson NVA's. They have a plastic collar under the collet nut, so you can really tighten them down, yet still turn the needle. They are more expensive, but are really a big leap in being user friendly, IMHO.

The K&B Universal NVA is available sometimes from K&B/MECOA, but they are not a bargain, direct. Sheldon's may have them (or not), at a good price. I have settled on .156" spraybars, anyway. Rich Oliver has the Jett NVA's, but they are .185". Too bad. If you have a setup that works with that, break the NV, and can't get a replacement by 8am, what are you to do? At least, with the .156" spraybar, you have options, and can find/borrow something to get you through a contest. Steve

I never liked the ST friction needle either and quit using them.
If I was going to have just one NVA it would be the K&B universal. There's plenty of meat on the spraybar to turn it down. Mine came from Frank Bowman. I've been running these a few years without problems.

Steve, Alan, Ty and Bill,

Thanks a bunch guys, much appreciated. The old universal NVAs that I think I remember, were much like the OS Max and Enya types. I haven't seen the K&B universal but will track one down and check it out. One example I do have on hand is the Fox which they sell for their 50 / 60 c/l version engines. I think I remember seeing a Brodak NVA, probably for their .40. Hmm, wasn't it kinda like a S.T. with the friction coller. Anyway, thanks again, Brian

>Steve, Alan, Ty and Bill,
>
>Thanks a bunch guys, much appreciated. The old universal
>NVAs that I think I remember, were much like the OS Max and
>Enya types. I haven't seen the K&B universal but will track
>one down and check it out. One example I do have on hand is
>the Fox which they sell for their 50 / 60 c/l version
>engines. I think I remember seeing a Brodak NVA, probably
>for their .40. Hmm, wasn't it kinda like a S.T. with the
>friction coller. Anyway, thanks again, Brian
>
>nice n tight, but bowed a little

I Fox type needle with a finer thread would also be good. If you are going to do one, do something entirely different and improve the breed. We have Nelsons and ST needles now and the OS is still around (but probably not for long).