Hilborn Fuel injection - small block Mopar

[Newbomb Turk]

We had a customer bring in a small block Chevy with a vintage Hilborn setup that had been converted to EFI. The guy who did the conversion charged him a bunch of money and gave him a smoke show about how great it would run. Ran like crap. Couldn't even get it to idle cleanly. So paying a bunch of money to someone is no guarantee that this stuff will work.
I've worked on several Hilborn setups over the years and they have all run like crap at idle. They typically run okay at WOT, but they have all sucked at low speeds. Guys love how they look but I'd never recommend them for the street. Even when converted to EFI. If you want stacks on the street step up to Borla.

Stack injection will never make the power a decent single 4 barrel will.

Idle shouldn't be that hard to clean up.

 

[Rt1976]

I've been running an original SBM mopar hilborn on gas for 5 years. Nothing I would consider trick, its a 366 that makes 625 horse.

It is a rare piece, talked to Hilborn @ PRI a few years ago and they concurred there were few made. They believed low hundreds but didn't really know. One stated they only did a run for Indy car and since they didn't sell they melted a lot back down.

It was a learning curve, idle setting is real touchy on gas and I don't idle it longer than needed as it needs to idle rich. I run a stick so I can clear it out easily.

If interested you can hear what it sounds like and see it in action here

https://www.youtube.com/channel/UCkounOf0SVon5WNAPrlUN-A

 

[TT5.9mag]

I've been running an original SBM mopar hilborn on gas for 5 years. Nothing I would consider trick, its a 366 that makes 625 horse.

It is a rare piece, talked to Hilborn @ PRI a few years ago and they concurred there were few made. They believed low hundreds but didn't really know. One stated they only did a run for Indy car and since they didn't sell they melted a lot back down.

It was a learning curve, idle setting is real touchy on gas and I don't idle it longer than needed as it needs to idle rich. I run a stick so I can clear it out easily.

If interested you can hear what it sounds like and see it in action here

https://www.youtube.com/channel/UCkounOf0SVon5WNAPrlUN-A

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Hell ya brother! That car is awesome!

 

[Charrlie_S]

Looks cool but good luck getting it to work. Those stack systems will only run on alky, they don't work with gas. You'll need to find an old timer with a big box of pills to dial it in for you. Lots of compression, fixed timing and a high idle speed will be your friend. If your tuner is really good you'll be able to pull to the line, do a burnout and launch the car without it stalling or dying on you!

I disagree. Back in 1959, I had a 324 cid Ford flathead in a 1941 Merc that ran Hilborns on gas
In the early '80's a friend bought a altered wheelbase 68 Merc Cougar with a Hilborn injected small block Chevy. We ran that a couple of times on gas before parting the car out. Both cars were sticks, not auto.
I do agree about needing to keep the RPM up. They don't like low RPM and don't take to idling

 

[66fs]

I believe Smithberg Racing bought out all the Hilborn stuff and knows how they work. Real nice to talk to also.

Smithberg Racing | Cylinder Heads & Manifolds

 

[71GSSDemon]

Mechanical fuel injection is a part of history and amazing when running/tuned correctly. I also have a set up for future build. I have been entertaining a hybrid set up where a Microsquirt controller would run a servo operated barrel valve. Seems like it could work and be much cheaper than a complete EFI. It is constant flow fuel, even with a closed valve which is why the throttle response is like nothing else. I hear you shouldn't run it on the street due to part throttle issues. I believe it is all in the tuning and barrel valve ramps - or use dial a jet, etc. I second Alkydigger - he i a great guy and super knowledgeable. I distinctly remember "everyone" telling me running a tunnel ram with 660's, a spool, and high stall converter wouldn't ever work on the street - constant fouling plugs, hard starting, horrific mileage if it even runs, overheating undriveable transmission, and can't steer on the street with a spool. Hmmm. Drives amazing and gets 12mpg.