Holden 9-port Red Engine - 2 questions for our mates down under......

[KnightEngines]

The Holden head does not have enough cross section to support a cylinder on one side of the vane - that's why it is not fully divided, if that was done itd choke.
The idea is to encourage as much flow as the cross section on the side of the vane with the open valve will support to increase intake velocity & inertia ram while still allowing 'top up' flow from the other side to make up the cross section shortfall.

Now I get what a lump port achieves, I have never seen a chev 6 head in person, I didn't realise they had a flat floor.

I can't see a reason why you can't use a vane as well, you'd probably want to be able to achieve 75% of the required cross section per cylinder on each side of the vane.
You could attach the vane to the lump port insert, or weld it directly to the intake manifold - that's how I've done the last 3, much easier than using capscrews through the original bolt hole to locate it!

Being a low rpm torque build I would think you should be able to raise the roof & widen the port enough to work with the vane.

I don't have any more vanes, I carve them by hand from a lump of 10mm thick alloy plate with a die grinder, hacksaw & file, it's a bit of a pita.

Have you tried removing the bolt boss and not running a vane?
So you have a fully open port with just a short bolt on the floor and a plug at the top.

Commonly done, but they are pigs down low, no intake velocity to speak off, average under 200ft/s with just a huge gaping port. Vane works a LOT better! I usually see velocity in the mid 200's with a vane.

[Fatman]

Have you tried removing the bolt boss and not running a vane?
So you have a fully open port with just a short bolt on the floor and a plug at the top.

Commonly done, but they are pigs down low, no intake velocity to speak off, average under 200ft/s with just a huge gaping port. Vane works a LOT better! I usually see velocity in the mid 200's with a vane.

The ports are pigs or the engines are?

[lc-gtr-1969]

I cannot answer for Tony, but I can vouch for the fact 9 port holden heads with the divider removed kill bottom end response. They will flow well on a bench but the big garage sized shared port kills power under 4000rpm. The effect when driving is like running a way oversized carb. Put a divider in and there is a gain in low end response with minimal reduction of peak flow.

[enigma57]

I remembered this thread and found it quick enough with a search.
viewtopic.php?f=1&t=24425

Thanks, Keith!

Fascinating read! I love projects such as this! Dan was ever the innovator and definitely a free spirit. That's why I found contributing to his early hemi build so much fun. He was always open to new ideas and never bound by the constraints of 'group think' nor 'consensus'.

Best regards,

Harry

[enigma57]

KnightEngines

Didn't people used to shift the entire head over on Holden 6's to get the intake valve farther away from the cylinder wall?

Did and still do! .060" shift makes a real difference, just have to end mill the bolt holes & plug & shift the dowel holes - or just use offset dowels.

Aha! I vaguely remember hearing of offsetting the head using offset dowels many moons ago! Have you any photos of this head mod? And once realigned, are there any issues with coolant holes lining up and/or head gasket sealing?

Thanks,

Harry

[Fatman]

The Holden head does not have enough cross section to support a cylinder on one side of the vane - that's why it is not fully divided, if that was done itd choke.
The idea is to encourage as much flow as the cross section on the side of the vane with the open valve will support to increase intake velocity & inertia ram while still allowing 'top up' flow from the other side to make up the cross section shortfall.

Now I get what a lump port achieves, I have never seen a chev 6 head in person, I didn't realise they had a flat floor.

I can't see a reason why you can't use a vane as well, you'd probably want to be able to achieve 75% of the required cross section per cylinder on each side of the vane.
You could attach the vane to the lump port insert, or weld it directly to the intake manifold - that's how I've done the last 3, much easier than using capscrews through the original bolt hole to locate it!

Being a low rpm torque build I would think you should be able to raise the roof & widen the port enough to work with the vane.

I don't have any more vanes, I carve them by hand from a lump of 10mm thick alloy plate with a die grinder, hacksaw & file, it's a bit of a pita.

Have you tried removing the bolt boss and not running a vane?
So you have a fully open port with just a short bolt on the floor and a plug at the top.

Commonly done, but they are pigs down low, no intake velocity to speak off, average under 200ft/s with just a huge gaping port. Vane works a LOT better! I usually see velocity in the mid 200's with a vane.

with a vane in the 9 port, do you run a 12 port style manifold with 6 intake runners?

[KnightEngines]

Harry - not on the holdens, plenty of wiggle room. Haven't got any pics of shifted dowel holes, only really do that when it'd be best if the shifting of the head is not easily spotted. It's a bunch easier to just use offset dowels or even just drill the dowel holes oversize & shove the head over before you torque it down.

[KnightEngines]

Fatman - usually a 'semi divided' intake, with individual runners that merge into a single runner about 3" out from the head face, the last couple I've done I've divided it mostly, but left a hole before the divider/vane to allow pulling from both runners as well as around the vane.
Still waiting on results for that style setup, shouldn't be too long.

[enigma57]

Harry - not on the holdens, plenty of wiggle room. Haven't got any pics of shifted dowel holes, only really do that when it'd be best if the shifting of the head is not easily spotted. It's a bunch easier to just use offset dowels or even just drill the dowel holes oversize & shove the head over before you torque it down.

Thanks, KnightEngines! Much appreciated. I'll take look at the 292 Chevy head / block fit up and see if I can gain any added clearance between intake valve and wall of cylinder bore by shifting head a bit.

Regarding your description of the semi divided intake......

Fatman - usually a 'semi divided' intake, with individual runners that merge into a single runner about 3" out from the head face, the last couple I've done I've divided it mostly, but left a hole before the divider/vane to allow pulling from both runners as well as around the vane.
Still waiting on results for that style setup, shouldn't be too long.

That is the way my intake is configured. Looking forward to experimenting with vanes after lump ports are done. Should prove interesting.

Unfortunately, DCOE sidedraught carbs with proper trumpets and either individual air cleaners or an airbox setup will not clear the steering column and master cylinder in my '57 Chevy LHD engine compartment, though.

So I am joining 2 of these intakes together at the sidedraught flanges...... Each forming 1/2 of a longer runner intake. The outboard half, I am converting to accept downdraught carbs. The inboard half, I will leave as is. Should 'just' clear my steering column and master cylinder.

This is the unmodified sidedraught intake that forms the inboard half of my 2-piece intake setup.....





And this is the modified intake that forms the outboard half of my intake setup (modified to accept DCNF downdraught carbs)......



















I will bolt the intake halves together using their otherwise unused DCOE sidedraught flanges to join them. Note to self...... Need to hand cut a gasket for that.

Thanks to a very understanding wife...... After I figured out what I wanted to do, I hand fitted the pieces at the kitchen counter (AKA 'work bench' for us old retired guys whose garages are full) and then sent the outboard intake half along with the carb flanges and filler pieces to Nick Smithberg and he did the welding and machine work. Outstanding workmanship, as always.

Best regards,

Harry

[Fatman]

Fatman - usually a 'semi divided' intake, with individual runners that merge into a single runner about 3" out from the head face, the last couple I've done I've divided it mostly, but left a hole before the divider/vane to allow pulling from both runners as well as around the vane.
Still waiting on results for that style setup, shouldn't be too long.

Thanks.Be interesting to see how that last mentioned setup runs.

[KnightEngines]

Well I just had a 292 show up for a mild performance rebuild.
I may have to ask some questions!

[enigma57]

I'll be happy to share what I've learned of them.There are some 292 specific issues not shared with the low deck 194/230/250 engines. What year engine do you have there?

FWIW...... Only the 1971 and later 292s have oiling provisions for hydraulic lifters. 1970 and earlier must use solid lifter cams. 1967 and later 292's have cast nodular iron cranks with 12 counterweights, larger 1/2" flywheel bolts and a total of 3 locating dowels for flywheel. Earlier 292 cranks have 6 counterweights and 7/16" flywheel bolts with a single locating dowel, same as Chevy V-8. 1963 US crank and 1963 + 1964 Canadian built 292 engines had forged steel cranks.

Best regards,

Harry

[chevyfreak]

Well I just had a 292 show up for a mild performance rebuild.
I may have to ask some questions!

Dont know in other countries but here in south africa they came with a very low comp ratio as stock. Lower than the 230/250 units.
My buddy has 2 of them. On both he milled the head heavily (like 2.5mm milled on one and other 3mm milled) to raise compression. He runs a 38dgv 2bbl weber on them. Rest he left stock. For a pickup it runs great, nice torque for towing.
I think with a cam change and headers it would be better and a very nice mild performer but my buddy is a stocker. He only keeps to the stock oe cams, manifolds etc. . Luckily no one is the same, i'm the hooligan in the pack and try many things.

Chevyfreak.

[KnightEngines]

I'll be happy to share what I've learned of them.There are some 292 specific issues not shared with the low deck 194/230/250 engines. What year engine do you have there?

FWIW...... Only the 1971 and later 292s have oiling provisions for hydraulic lifters. 1970 and earlier must use solid lifter cams. 1967 and later 292's have cast nodular iron cranks with 12 counterweights, larger 1/2" flywheel bolts and a total of 3 locating dowels for flywheel. Earlier 292 cranks have 6 counterweights and 7/16" flywheel bolts with a single locating dowel, same as Chevy V-8. 1963 US crank and 1963 + 1964 Canadian built 292 engines had forged steel cranks.

Best regards,

Harry

It's a '78 motor.
I'm planning on a thorough rebuild, balance & mill to zero deck.
1.94/1.5 valves with some mild basic porting.
Mill head to get comp to 9.5:1
Bit of a cam, hyd lifters, maybe into the early 230's.
Roller rockers on 3/8" screw in studs.
Clifford twin weber intake setup & headers.

[enigma57]

Should be a nice build for you. The '78 292 should have all the factory upgrades (12-counterweight crank with 1/2"flywheel bolts, HEI distributor, hardened exhaust valve seats, etc.).

Common practice here is to run 7/16" screw-in rocker arm studs and big block Chevy rockers. Valves, springs, retainers are small block V-8 pieces

Best regards,

Harry