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I thought the golf ball effect helped speed haha yea I’m think I’ve seen that thread on Aussie v8 was tk383 hptpete or something he was having ago at. What did you use for raising the short turn side they are super low and almost a 90 degree turn right at the valve

Dazza92VP wrote:I thought the golf ball effect helped speed haha yea I’m think I’ve seen that thread on Aussie v8 was tk383 hptpete or something he was having ago at. What did you use for raising the short turn side they are super low and almost a 90 degree turn right at the valve

Hello Dazza92VP, yes you are correct it was HP_Pete, who I have alot of respect for. Both of them actually are great guys and very talented not to mention helpful. I love people who ask questions and then want to argue with a SME professional. NOT!

I normally use Devcon plastic steel or F. It dries very hard and is fully shapeable. For added strength (and to hide the repair I have ground some spare heads and mixed the shavings into the epoxy. This therefore colour matches it and makes it look as part of the head. There is quite a following and I know some head guys use Z Spar A788. The trick with both of these is if you are not pulling the motor down every year you will need to drill keying holes into the floor to make sure it says there. This stuff dries like rock and if it lets go will bend valves or damage pistons if ingested.

However, it does make a bloody good surface to then grind and shape the port properly. I will not show my race heads as these are a little secretive due to the R&D (and the class i am involved with) but if you start with say 5mm - 10mm from the floor you will be able to do some good tuning. You will need to do something about your manifold as well but seeing I have a twin throttle (similar to a walkinshaw manifold), i cannot advise to how you will go with a bunch of bananas (although I do know that modifying the bananas into a walkinshaw eske manifold does give good results.

If you know someone who can use a flow bench or has access to it then spend some time looking at how to improve your port velocity. I would highly recommend polishing the roof but leaving the floor not perfect.

cheers
Oldn64

For stocker/mild 304 just clean up dags & get good valve job done...comp is low so they need to be shaved just to see decent gain with small cam in most cases.

Matchport inlet runners couple inches up the runners & call it done if keeping bananas....dual plane elebrock & throttle body elbow would be next step up & perfect for small cam/head shave later on.


Got f280 355 harrop single 750dp...heads are just cleaned up,stock valve size & seats redone etc.Mild almost heads are fine for most applicatications.

Cool yea I’ve got some devcob but wasn’t to sure how it would go with heat and expansion rates and getting it to stay in place. At this stage I’ll just polish, shape and match the ports and leave it at that. Unfortunately I don’t have access to a flow bench and I don’t think work would appreciate me booking a flow bench to workshop account seeing as we only do trucks. I was going to build one but once again children and house come first so many projects and ideas and either time, money or space are deciding factors. Need to get my mig up and running have some ideas for a modified banana manifold but need aluminium wire and argon I’ve drawn up some plans for a couple of design.

daz if you're going to mig ally you'll also need to preheat and get your work hotter than the fires of hadies. you need a shit pile of amps and stay covered up when you do, take it from burnie tanningtons TIG adventures.

oldn64 wrote:Hello Dazza92VP,

Yes you can go smoother. I use emery cloth to finish mine off, you dont want it to look like this........LOL

rough.jpg (125.08 KiB) Viewed 6405 times

rough2.jpg (50.24 KiB) Viewed 6405 times

These are a little too rough hehehe. (was from thread where someone was having a go at a very good head porter for having mirror finishes on everything, he got burnt hahahaha)

Look at your short turns as these help quite well. Smooth your valve areas and I would CC and unshroud your valves.

I would also port and flow your oil pump as these are known restrictions with holden pumps and then look at cleaning up the valley casting. Oil return to the sump can be bad on these but if you are considering track work then seriously look at running an external line back to the sump from the back of the heads. I would also do priority mains oiling as this will allow you to turn the motor higher without killing it (again due to oil filling the heads up) I know you stated street car but sometime a little extra time in places makes for a really nice system.

The big thing with raising the intake floor is to get the port flow up thus allowing you to out accelerate a large port head. I dont know how many 308's with large intakes cry when a small port early head out runs them at Sandown down the straight because the port does not come on song early enough. I am have a mate which we did raise the port floor on his VN heads and he runs twin DCOE 48's (i think) on his 308 in a VK and out runs a number of other 308 and even a couple of 355's with this setup. Make sure your transistions are smootha nd you should knock this out of the park

Yes Kline and vitol are worthwhile investments.

Good luck

cheer
oldn64

Holy Shit!

would certainly create some turbulence to atomise the fuel

Not much has changed since last time I posted but did manage to get my rear calipers on so now I’m running corvette c4 rear calipers same as vn group a and a set of vn group a vented and slotted rear discs from dba all fits perfectly inside my 15 inch rims No modifications to anything except remove the dowl pin from the brake line and get some grade 10.8 bolts the same length as the original commodore bolts but in imperial thread the same as the corvette/group a calipers even uses same size standard commodore pads
Only problem is I’ve had a squeaking noise from the rear right for years thought it was just a warped disc but apparently years ago during my apprenticeship I bent my right hand axle in the press doing the wheel bearing so I’m up for a new axle
The 304 is almost complete as well ended up just throwing a set of standard vn heads on it for the moment so lost a little bit of compression as it’s a vs s3 block with smaller cc heads but have managed to clean and paint most things and fit up the electric water pump had to modify the pump outlet and weld it on to pass the belts and drilled and tapped the pump housing for my heater core
Only things left to do are wiring for flex out puts for variatronic steering and the water pump modify the crappy genie extractors and paint the kframe up

What thread and diameter is the caliper bracket bolts and were the mounting hole on the diff side of things needed to be drilled?

I also have a pair of group A calipers I got NOS from the states but still need to source the cast brackets for them.

No drilling was required at all bolted straight onto the existing axle tube bracket I’ll pull a bolt out and measure and check the thread pitch and length needed if you want. Didn’t even have to cut the backing plates like you do with the vt calipers upgrade and hand brake is direct fit as well no having to do that sketchy weld a vt handbrake shoe to a vn one

yeah I know the fit is the same as stock just wasn't sure if the bolt diameter was bigger or not being imperial. So I am guessing they must be 3/8" then?