I'd like to up the pressure in my fuel system and keep hoping to find a set of 16AS Hilborn nozzles , but so far no luck. I do have a set of 7AS nozzles that theoretically I could drill/ream out and experiment with - so I gotta wonder - has anyone ever done this - what were your results? I won't do this totaly blind - my thinking was to at least leak them all down to make sure they are acceptable in terms of being the same leakage rate. I haven't looked real close at my "donor" nozzles yet, but it seems like I could unsolder the ends - make the mods and solder them back together fairly easily. So what say you?
You cant buy new ones from Hilborn? I dont know if you can drill them, it might make them spray funny. I know you shouldnt drill a pill and hope for consitancy in flow.
I don't know if they are tapered - I will have to look at that. And YES I can buy them from Hilborn (pretty sure) but last I knew they were like 3 bills for a set of 8. Yikes!!! I also thought about possibly modifying them to take motorycycle jets - they are pretty accurate and cheap! Might be doable fairly easily - not sure.
Along with Good Vibrations, you could also try: Cavlieri Racing, Holbrook Performance, or Dale Wilch for used ones. Brian
Once you figure out what size or diameter you will want, call Jim over at Enderle and get a set of nozzles and bodies. They are flowed and have to fall within their flow parameters. And they ain't three bills!! Wanting to go smaller to up your system pressure may show up any weak spots in the system and you will need to make sure you have a filter coming out of the pump. Having used units and components from all of the major players in the FI game, some of the stuff they want you to think is super critical just is not and you can spend a bunch of $$$ you may not have to. K
I drilled all my nozzles the only critical I encountered was the radius on the entry and square on exit (deburred). This was on a sprint car.
I also made my own metering valve body out of br*** to get away from the curse of alcohol / aluminum corrosion.
Have you tried Mike Chilando in Nashville? He's an ebay seller but sometimes has some good deals on used Hilborn stuff.--- WWW.Alkydigger.com
I sold him a BBC set up ..good guy to deal with ... Rick ==============================================
I never have but I'm sure that someone has, I mean how did the hole get there in the first place. I have a set of jet drills in the Ol' Man's tool box. I think that things that we consider majic were way more common in the days prior to bolt together hot rods. Hell do your research and give it a whirl, the worst that could happen is it won't work.
When Stu made his first nozzles he found that he could drill a bunch of them and they would flow totally different. Then he found that the lead-in radius was absolutely critical in the flow rates, and then got them dialed in pretty good. Nozzles being used for flow-control is a pretty crude way of doing it, as all constant flow injectors do, but when they are all matched well, it works okay. Hilborn is damn proud of their stuff, and it shows in the prices. I wouldn't buy new nozzles from them, and instead would use the Enderle type, as has been suggested. Running a leak down test on the reworked nozzles might seem like a good way to measure them, but it is not. Two big sources of error: 1. Air is compressible, fuels are not. 2. The flow is highly dependent on the density of the fluid, and air at 100 psi is about 100 times less dense than fuel, meaning that slight differences in readings on the leakdown gauge for air would be multiplied by about 10 for fuel. If you want to run a flow test with water, do that. Viscosity is negligable in this case, and the density is close enough. I built a device to do this with an old R-22 tank, an air pressure regulator, a few valves and plumbing and two good pressure gauges. I never bothered to figure out the actual flow rate, instead only comparing the nozzles to themselves.
You have the 7s and don't want them. What have you got to lose? I am not sure how running bigger nozzles will up your pressure.
There was an article a while back about the Surfers and how they dealt with injectors. Completely different than the standard setup of the time, but they built a test stand to flow their injectors. If you want to mess with them, that would be the place to start. Build a tool to measure what you are doing. They also ran high presures and small orifices, increasing the atomization.
The Hilborn screen nozzles are 3 parts soldered together....heat them up take apart drill and sliver solider back.......not as easy as it sounds but trust me it works.....
7 AS is a gas nozzle which are hard to find,I know looked for a long time,16 should not be hard to fine its a alky nozzle. I have a set of nozzles but think they are 14 I will check.
Thanks for the advice fellas! I thought about testing them with water, but figured I'd start with a leakdown first - if it don't p*** that I figured there isn't much point to go to the water. I have leakdown numbers on my current nozzles and I compare them to EGT's just as a sanity check. I like to leak them down every so often just as a feel good type thing. I know it'd b eway better to check them wet - I just haven't taken the time to build one yet. I figured it would be pretty easy to set up a hilbilly test stand - manifold - hose adapter - and a solenoid as my on/off setup. Have each one flow into a separate container - voila - I may not know EXACTLY what they flow, but I'll know they are the same - that's good enough until I figure out where I want to be. I've got some misc nozzles - I think I'll fiddle with them before I screw up any good ones. I hadn't thought to look at the Enderle stuff - I just ***umed they were all PROUD of their nozzles..........
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