gerg

6AL-programmable, never looked back. While not quite up there with the tuneability of an aftermarket ecu, they do what they're designed to do, and well. Instead of a 3D map like on an ecu, they have 2 separate curves (rpm and load) that subtract timing from your preset max advance on 2d graphs, to an absolute total of 30 degrees, 25 on the graphs and the other 5 through rpm or switched retard. They have launch retard and step retard functions too, as well as rpm limit. Quite impressive for the money. Need a GM map sensor with it too

The internal plunger is what does the pumping. It is energised by the solenoid windings which constantly cycle on and off by the simple electronics inside the body. The pulsing is always there as long as you have power going in. When the pump gets up to pressure, all that happens is the plunger cant pump any more so doesn't move until demand for more fuel lets it move again. If it's stopping after getting up to pressure, I'd say the plunger is in its idle position and getting stuck there, but when it finally decides to start moving, it's freed itself up and doesn't seize until it reaches pressure again. I reckon a new pump is on the cards.

Ok must be square block Aussie-cast then. Didn't know about the valve notches.... You could have had an unofficial RPO block. Ford did all sorts of funny stuff trying to get rid of the Phase 4 bits after all the shit hit the fan in '73

Is it from an aus-built car or import block? What is the prefix on the engine number? D or square block?

I see what you're saying Ando about 1 & 6 but i just look at those tight turns and shake my head. If the insides of those long sections resemble the outside, it would sort of act like a bit of a plenum as well as a runner, so i get why you say it would be dominant. My old red motor marine manifold had similar issues and after i opened up the inside radius on each runner (especially on the end cylinders) it gained 4kts top speed and was much smoother and torquier getting there. Agreed, got nothing to lose by fitting it, except maybe fuel economy with the Holley.

If you've got a Dremel or die grinder, first thing you could do is tidy up the entry into the runners from the plenum. Air doesnt like sharp edges like that, so just put a nice little radius on each entry. Perhaps you could take a bit out of the short turn into 1 &6 to reduce the restriction. Anything more than that will require opening it up and porting out the guts, re-profiling some of the runner mouths and maybe even cutting out some corners and welding in some rounded sections. That's getting pretty involved and will be more trouble than it's worth.

Yeah that actually would be a step back from a Redline by the looks of it. I dunno what they were thinking when they designed it, probably would be a very slight advantage over the (very average) stock weber one. Still, going onto an XD, it would be replacing a single strommy, so anything would be better than that

If it's anything like a Redline, it will probably starve 1 & 6 above 4 grand. Still, better than a stocker. Post some pics, that may help.

You had me at "Clevo Time"

Though that could be just a centre drill for when they locate the rolling/cutting process on the thread. Cant see how deep that hole goes there

"OEM".... Lol

Always loved the box falcons in crystal mint or similar greenish turquoise colour. Gold spokes and machined finish on the rims.... Magnifique!

I know all the folks in the know swear by carbies around the 600 mark, but here's an article where they test a whole bunch of Holleys on a stout 383 SB Chev, and the results are very interesting. http://www.superchevy.com/how-to/148-0403-seven-holley-carbs-test/390-cfm.html The smallest one they chucked on, (the 390) despite obviously choking an engine that size, still made 409 hp and got good torque all the way up to it. So if you plan on making anywhere near that power (and i doubt you will) maybe a smaller carby like a 390 or 465 is a smarter choice.

Might wanna go roller rockers with that cam, as a general rule you shouldn't go over 0.500" lift with stock rockers. Might be a little hairy for the street too. May i suggest the next one down... The CT142 517. It has 0.510" lift and 218 duration vs 0.534" and 230 on the one you want. If you want to stick to that cam, you could go up a lot more in compression on LPG. I reckon 11:1 would be more like it.

My Clevo runs a standard volume pump and at idle, sits at max on the gauge at any temp except once completely warmed up. Even then, it never drops below half at idle, even on a stinking hot day in traffic. Your crossy will be no different. Ford 6s and V8s use Gerotor pumps, which are much more efficient than gear pumps like what Chevs and Holdens use, so unlike them, no hi-vol version is needed on a Ford. Either tell your engine builder you want standard volume and standard bearing clearance, or find someone else.

Lol now we know how to make Ando an angry man

Sounds the goods, moderate mods but together will give a nice street engine that puts a smile on your face. Gotta ask though, why the hi-vol pump? It's not a race engine so not really needed. Pretty much all advice on here says to go standard volume.

If this is a "spare" motor, what happened to the one in your XF? Are you building this one up or just chucking a cam in?

Anyone who runs a Carter/Edelbrock AFB or an aluminium Holley will know all about vapour lock when it gets warm under the bonnet. You can make a carby insulator out of a bit of marine ply, then paint it with epoxy to protect it from fuel. You do need to be handy with the wood tools and have a router available with its various bits. Many speed shops actually sell them but they start at around 70 bucks. A lot of coin for a lump of wood i reckon. You could even make it extend out to shield the bowls from radiant heat, just might not look too flash.

We've got 8-tonne trucks at work that get better than that

Wow they really mustn't want your business if they're charging that much. I'd expect a cam thrown in with that as well, with a couple of oil filters and 2 lots of oil (one for break-in). That's just robbery.

Good explanation Stumper, I'm pretty stoked too! Just hoping this newfound efficiency shows at the petrol pump... It's been a shocker lately: about 20l/100km

This mod was inspired by Stumper's thread on Street Stock Speedway and the carby mods he's done. When i had my 4011 Holley apart the other day, I noticed that the barrels had some pretty rough casting marks and misalignment between the top and bottom halves of the Venturi. Might not show there but it's like they took the safe approach with their mouldings and made the top half slightly narrower than the bottom (so there's no chance of any ledge jutting out) with a distinct inward ridge all round. I looked at the finish and all i could see was turbulence and restriction, yet on my little 302 it probably wouldn't make any difference, or so i thought. Regardless, i just couldn't help myself... Anyway about 10 min with my little Dremel and this is the result: So i slapped it all back together and did notice a smoother transfer to main circuit but was a little doughy up top compared to before. I figured that more air was flowing around the booster instead of through it, so less fuel was being pulled out and needed more jet to compensate... So i thought (again). Chucked in some 70s up from 67s and it went worse! Yesterday i chucked in some 64s and was slightly better, so today i thought I'd go way down to 61s and blow me down, it's going pretty good! Maybe the extra flow is giving more velocity and more booster signal, so it draws fuel harder. Hard to tell what's the go in this hot humid weather but it's fine for now. What I'm trying to say is that messing with fiddly things like carbies can be trouble and can give you the opposite result to what you expect, but if you're keen to learn then this is the only way. And thanks Stumper for showing what can be done with a bit of man-shed engineering

If the pacies are the 6-3-1s, double win. I'd go 6-3-1 any day. Motivators were a cheap line of Genies i believe. I've not liked Genies for their thin walls. Seen them burn out within a few years, but pacies are much thicker and will last over ten years if you don't wrap them.

They do have a tendency to seize if rusty or have bits of crap in them