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| Hilborn catalog https://slantsix.org/forum/viewtopic.php?f=26&t=64928 |
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| Author: | hyper_pak [ Fri May 29, 2020 7:15 am ] | |||
| Post subject: | Re: Hilborn catalog | |||
Enjoying all this history. Does anyone know where any of Wilford Day's cars ended up? Are they still around?
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| Author: | slantzilla [ Fri May 29, 2020 8:31 am ] |
| Post subject: | Re: Hilborn catalog |
IIRC, the motor is a coffee table now. Bob Stepp had it for years. |
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| Author: | CNC-Dude [ Fri May 29, 2020 5:40 pm ] |
| Post subject: | Re: Hilborn catalog |
GregCon wrote: For a Slant Six, it would not be too tough to make your own. Or rather, it's one of the easier engines that you could tackle. It'd be even easier if you bought, say, a set of BMW (inline 6) throttle plates and adapted them to the Slant head. For example, here is a very nice set for $300 on Ebay right now. The port shape is not the greatest match so maybe it would pay to look around for a Toyota or other make that had a better match. But in any case, there is a lot of good engineering and machining and parts all for $300. I just bought a CNC mill...if I can figure out how to run it, this is just the sort of project that would be fun! It's got a steep learning curve. Does it use g-code programming or conversational? |
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| Author: | GregCon [ Sat May 30, 2020 11:45 am ] |
| Post subject: | Re: Hilborn catalog |
Great background Roger. I read that the setup was based of half of a Maserati V-12 setup but that could be false. CNC, the mill use G-Code and I have OneCNC software. I'm sure I do have a lot to learn but that's never stopped me before lol. I do wish I had a friend close by who could show me how to do it...I learn very quickly if I can watch someone else do it as opposed to reading or videos. Oh well... I have a small block set of Hilborns and am planning my first project to be making a manifold for them. |
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| Author: | Rick Covalt [ Sat May 30, 2020 2:06 pm ] |
| Post subject: | Re: Hilborn catalog |
If the Hilborn (and others) are constant pressure systems, what happens to the excess fuel that is being sprayed at the intake tract when the Intake valve is closed? May be a dumb question but it seems like there would be a lot of excess fuel there?? |
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| Author: | Reed [ Sat May 30, 2020 2:48 pm ] |
| Post subject: | Re: Hilborn catalog |
Rick Covalt wrote: If the Hilborn (and others) are constant pressure systems, what happens to the excess fuel that is being sprayed at the intake tract when the Intake valve is closed? May be a dumb question but it seems like there would be a lot of excess fuel there?? Same thing thats happens to the extra fuel ina TBI or batch firem MDFI injection system- the fuel hangs out there pretty much fully in suspension until the valve opens. Think about this- if an engine is idling at 600 RPM, any given intake valve is opening 150 times per minute, or 2.5 times per second. Now imagine the engine is turning 3000 RPM. That is 750 valve openings per minute, or 12.5 times per second. Any extra fuel just won't hang around behind the intake valve long enough to do anything bad. |
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| Author: | Team Green [ Sat May 30, 2020 3:31 pm ] |
| Post subject: | Re: Hilborn catalog |
It's the Dragmaster dragster that has the unit based on the Maserati. If you look at the photos of that car the intake has the throttle body angled to the head. Has anybody looked at older Hilborn catalogs to see when they started selling the unit for slant? A big gap from the Dragmaster that was 1962 or 1963 until 1969. Roger could you tell us what number your intake is? thanks, Mark |
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| Author: | Rick Covalt [ Sat May 30, 2020 4:39 pm ] |
| Post subject: | Re: Hilborn catalog |
Quote: Any extra fuel just won't hang around behind the intake valve long enough to do anything bad. I guess you are right but those systems are not spraying fuel basically just ahead of the valve. Just wondering. I think they are cool, but I think I'll hang on to my Webers! 
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| Author: | GregCon [ Sat May 30, 2020 6:39 pm ] |
| Post subject: | Re: Hilborn catalog |
Constant flow systems are really intended for WOT operation where it makes little difference (if any) that the spray is running regardless of valve position. At 6000RPM, the valve is opening 50 times per second....fuel is a liquid and liquid doesn't really like to stop and start...it's a sluggish form of matter. It's better to establish a good, steady, spray pattern and don't worry about the starting and stopping. There's also probably some merit to the idea that the fuel helps cools the intake valve. I've read that the high RPM Indy engines spray the fuel directly and purposely on the intake valve head so as to cause a flash-reaction....the fuel instantly vaporizes when it hits the hot valve and then is sucked in. On my injected engines I've tried hard to do the same...I aim the spray right at the valve. Theory is great, but it can also get you running in circles. Here's the bottom line...a properly set up mechanical injection system (like a Hilborn running Kinsler nozzles and VST) is 'vicious' power...far better than carb. You're spraying fuel out of a nozzle under pressure directly into the port...not sucking it through a vacuum venturi from somewhere upstream. Companies like Kinsler know their stuff....they will sell you a set of matched nozzles that put out a beautiful mist. A good mechanical nozzle spray makes most EFI nozzle sprays look miserable by comparison. Personally, I have never driven any vehicle, including EFI, that has the raw acceleration of a mechanical injection setup. I don't mean absolute max HP, but all of the other points along the way. Imagine your carbureted taking 25% less time to run through each gear. It's unmistakable. I had a guy tell me once that the abrupt acceleration is aided by the mechanical pump...there is a no-lag relationship between engine ROM and increased fuel flow. The issue with mech FI lies in the difficulty of producing a nozzle that can flow a SMALL enough amount of gas to behave well at low speeds. Even worse, they don't like to operate at low throttle position, steady 'cruise' conditions. The fuel tends to 'ball up' rather than spray and you'll get a fair amount of 'loading up' and missing as the engine tries to cope with un-atomized fuel. As long as you are accelerating or at WOT, it's hell on wheels. It's also easy in most cases to do all the 'ram tuning' you like by easily changing the length/shape of the tubes. |
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| Author: | slantzilla [ Sat May 30, 2020 7:15 pm ] |
| Post subject: | Re: Hilborn catalog |
One ofmy old racing buddys had a '39 Ford with an injected 389 Pontiac in it when he was young. He basically said the same thing. It was awesome at WOT, but pretty much sucked everywhere else. He said he took his Dad for a ride in it, and Pops was not impressed. It went up for sale. 
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| Author: | curmudgeon [ Mon Jun 08, 2020 7:00 am ] |
| Post subject: | Re: Hilborn catalog |
Another forum I follow is landracing.com, the primary one for those running at Bonneville and the other LSR sites. Someone started a thread on a slant-powered car that ran at El Mirage and Bonneville which used mechanical fuel injection but without any butterflys. Considering the discussion here I thought this would be interesting reading. It is lengthy but worth it. The thread actually starts in the SCTA Rules section under the 2020 Rule Books thread with comment #9: http://www.landracing.com/forum/index.p ... #msg330563 After reading #9 jump to #20, 21, 26 and 27. The comments then go to a thread of it's own: http://www.landracing.com/forum/index.p ... #msg330633 I am not the most computer oriented person - a big thanks to procycle for getting me this far. |
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| Author: | hyper_pak [ Mon Jun 08, 2020 9:50 am ] |
| Post subject: | Re: Hilborn catalog |
Very interesting reads. Too bad there are no pictures of the deeds. Thanks for sharing. |
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| Author: | GregCon [ Mon Jun 08, 2020 10:12 am ] |
| Post subject: | Re: Hilborn catalog |
Yes, very good information! |
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| Author: | JR [ Mon Jul 06, 2020 6:15 am ] |
| Post subject: | Re: Hilborn catalog |
Im the one with the Dragmaster unit. It is stamped #101 (Hilborns prototype). Im at work and don't have the time to type out the whole story right now but here is a link to the Facebook page I made for this very slow going project (too many other toys to finish at the moment). https://m.facebook.com/dragmasterdartsix/?ref=bookmarks |
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| Author: | hyper_pak [ Mon Jul 06, 2020 10:21 am ] |
| Post subject: | Re: Hilborn catalog |
JR, thanks for the link. You could make your own table if you can't find the original one. |
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