Harv's McGee injection thread

[Harv]

This is the McGee set that I didn't buy. It was supposed to be Falcon 2V, but some Googling seems to show the manifold bolt orientation is wrong for any Falcon 6 I can find.

Any Fraud fans know what this fits (will take wild guesses from the non-Fraud camp too ).

McGee injeciton for Falcon 6 1.jpg (1.63 MiB) Viewed 623 times

McGee injeciton for Falcon 6 2.jpg (1.9 MiB) Viewed 623 times

McGee injeciton for Falcon 6 4.jpg (1.76 MiB) Viewed 623 times

Cheers,
Harv

[Blacky]

LOOKS LIKE ITS SET UP FOR A WEBER MANIFOLD ???

[Harv]

LOOKS LIKE ITS SET UP FOR A WEBER MANIFOLD ???

Agree - looks like triple DCOE's. I don't think any of the Falcons came from the factory with triple Webers, but thought I'd ask (my Fraud knowledge is slim).

Because the manifold is made of three separate throttle bodies, you could use one throttle body for a car with only a single Weber, two throttle bodies for twin Webers etc. My guess is that the Falcon that these came off had an adaptor like this one:

Ford 250 crossflow Weber manifold.jpg (19.79 KiB) Viewed 600 times

So not really a McGee Falcon setup... more like a McGee Weber setup that someone has cobbled together with angle iron to suit a Falcon.

Cheers,
Harv

[Harv]

Back in 2020 I had the McGee pumps flow tested. The test results were disappointing the grey motor McGee (sliding vane) had too much internal clearance, and the red motor McGee (gear) would not take suction. I really wanted to use the grey motor pump on the meth monster or FED projects, as it sits neatly on an angle drive and slips in under the Repco head inlet manifold.

Managed to find a pump rebuilder/injection whisperer close to home who has a long history with speedcars/speedway. Took the grey motor pump over to him, and let him loose to fit, fiddle and flow test.

My seal replacement had not been successful (leaked like a sieve) so it got replaced. Interestingly, the spud drive is unique to the McGee pumps. I had thought it identical to early Hilborn (pre-hex drive), but apparently not. Some polishing of the vanes to remove pitting, and on to the flow bench. Pump flows OK, but runs out of grunt at 2000 pump-rpm. These pumps are usually cam driven, which would mean that at 4000 crank-rpm the pump would no longer keep up with engine demand. This is not good news. I need to spin this thing out to twice that crank speed, and the idea of leaning out at the top end of the track is horrifying.

I might get away with under-driving it (say at 1/2 crank speed), but only if there is enough pump flow at that speed to feed the engine. Can't readily do that with the angle drive either without regearing it. Bugger. Plan B is to run the red motor McGee pump, or failing that the Hilborn BL420 pump I rebuilt. Suspect neither will fit under the Repco inlet manifold, so will need to be driven off the cam snout, crank or supercharger shaft. Will take a box of McGee bits over to him this week and see if we can work out a plan.

The only good news is I found out now. Finding out later (when the engine bay layout was finalised) would be painful. Finding out by having molten aluminium sparkles coming out of the zoomies as I pass the finish line at 8000rpm would have been worse.

Managed to find a machinist locally to finish off the two McGee angle drives I bought a while back. Another speedcar gentleman. I own three McGee angle drives - a complete one, one that needs the shaft being made up, and a bronze one that needs finalising too (bits are there but need machining). Dropped off an old dead grey motor cam (with thanks to Clive Cams) to provide the gear, and an old dead dizzy shaft for the shaft. Gave him a call this week, the bronze one is done and he is starting on the alloy one.

Slowly, slowly.

Cheers,
Harv

[In the Shed]

McGee fuel injection angle drive distributor $450

https://www.gumtree.com.au/s-ad/adelaid ... 1309282183

[Harv]

There is a lot of work in that to make a functional unit. Machine two bearing lands, drill centre bore, face/drill and tap top surface and make up lid, drill one (or both) entry ways, machine clamps and drill and tap for setscrew, cut down camshaft and recover gear, mill down distributor shaft, weld together gear and shaft, press-fit bearings, assemble.

Neat job for the home machinist, and happy to help out the purchaser if they want dimensions/photos to work to.

Cheers,
Harv

[Harv]

Piecing together a historic fuel injection system has proven to be far from easy.

I have a bunch of pumps, including three McGee pumps. I really, really wanted to use a McGee pump with the McGee injector. Of the three pumps, only one is salvageable. That's a pretty low hit rate for pumps that were not overly shabby when I bought them, and after fettling by both one of the big names in mechanical injection tuning and a very experienced Speedway fuel technician. The McGee pump designed for the Repco head will not gain suction (despite fettling), and is probably only good for a display engine. The first hex-head pump is sleepy until 4000rpm, and then low on flow after that (again despite fettling). Probably only good for a cackle car.

The one McGee pump that is serviceable turns out to be undersized for what I need to do. It would support about 160HP on methanol (perhaps double that on petrol), and I am aiming for 220HP on methanol. Bugger.

So looks like I cannot run a McGee pump. Time to look at the Hilborns I have. Back to the spare parts department and I have a PG150C #0. It flowed up OK, but has about twice the fuel flow that I need - see attached.

Pump sizes.docx

(17.36 KiB) Downloaded 2 times

What I really need is a PG150 #00, which is about smaller than the PG150 #0 I have. As I can't lay my hands on a #00, I'll use the #0 but will have to drop the fuel capacity. This is done by running two return flows back to the tank - one through a large pill (to absorb most of the flow) and one through a normal size pill (which will get changed as the car is tuned).

So on the to-do list is to build a two-pill primary bypass for the FED, and sell the Hilborn angle drive and Enderle pumps that are waaaaay too big for what I am doing.

Cheers,
Harv