Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

304 VN AERO REBUILD (304 stroked to 350ci flat top pistons std 4" bore)

losh1971

Well-Known Member
Joined
Jan 17, 2010
Messages
22,391
Reaction score
22,005
Points
113
Location
North Tas
Members Ride
VE Series I SS Ute
Paint not thick enough for a buff?
 

bjf66

Well-Known Member
Joined
Apr 11, 2021
Messages
909
Reaction score
1,245
Points
93
Location
Mt Martha Vic 3934
Members Ride
VN HDT Aero
good question
I think I would be happy just to give a rub and squirt of paint
 

bjf66

Well-Known Member
Joined
Apr 11, 2021
Messages
909
Reaction score
1,245
Points
93
Location
Mt Martha Vic 3934
Members Ride
VN HDT Aero
Comp cams stuff arrived 24 hrs after ordering from VPW, seems Aust post getting back to where it was pre-Covid
I had some spring cutters #4718 already here which is 1.44" ID spring pocket / 0.630" guide boss, so cut the seats to correct depith, however guides need to machined down to 0.560" OD, so need another spring cutter # 4733 to make final cut
Or alternative drill out the spring locators from 0.570" to 0.630" (16mm) to fit over the guide.
Unfortunatley dont like my chances with chrone moly retainers
so need to grab the other spring cutter

Had a dumphy fit with valve reatiner, and 10 degree locks measure 1.77" installed height which is perfect

is there any tool which can help with installing 7/16" UNC thread into head for rocker studs
Like a spacer you slip in over one of the existing bolts while you start the thread in other hole ?



weights grmsoriginal GMH setupnew setup
valve spring7866
retainers2212
locks33
No one has the spring cutter CC-4733 which can cut the valve guide down from 0.630" to 0.570". So thought I would try drilling out the guide to 16mm. The CrMo is dam hard. Managed to get 2 spring locators drilled, and then decided to ask local head machinest to machine out the ID


drilled out the 5/16" unc rocker stud holes to 3/8", in 3 steps using the drill press and level so nice and easy
so all set to tap the pedestal boss for 7/16" UNC
Need to machine off 0.350" (need to check this again) for allowance for guide plate, and rocker stud nut
Using BBC ARP rocker studs
Need to organise the pedestal cutter, unfortunatley phoned around cant find anyone that has the proform/or Comp VCams cutter in stock

I think I'll just order it from summit in USA, it may take few weeks, but that okay, plenty to keep occupied with

So only other decision for heads is:
  • either to go with upgraded stainless valves 2.02/1.6" as I heading to USA in few weeks so thinking I could get a set of proflow Mildon 21-4N valves which they offer with 5.200" stem to suit holden
  • a little port work, although I smooth up the exhaust ports a little to smooth them out, but whether paying $1K for the port work is warranted of not
  • I think with the upgrade in Valves $450 would be better option.
  • still thinking what to do
 

losh1971

Well-Known Member
Joined
Jan 17, 2010
Messages
22,391
Reaction score
22,005
Points
113
Location
North Tas
Members Ride
VE Series I SS Ute
$1000 seems a lot for 5-6 hours on the porting tool. I'd have them cleaned up and spend say $500. But get the bigger valves too. I know on my old V6 4 hours of porting smoothed out the power delivery, so on a Buick it was worth it I would think 304 would be worth it too.
 

bjf66

Well-Known Member
Joined
Apr 11, 2021
Messages
909
Reaction score
1,245
Points
93
Location
Mt Martha Vic 3934
Members Ride
VN HDT Aero
yes, I was estimating havent received any quotes or gone out to ask anyone
Thought just get the releaved / neck down valves, and see how this went
 

Immortality

Can't live without smoky bacon!
Staff member
Joined
Apr 15, 2006
Messages
22,480
Reaction score
19,935
Points
113
Location
Sth Auck, NZ
Members Ride
HSV VS Senator, VX Calais II L67
You might find this interesting

 

bjf66

Well-Known Member
Joined
Apr 11, 2021
Messages
909
Reaction score
1,245
Points
93
Location
Mt Martha Vic 3934
Members Ride
VN HDT Aero
ordered the 2.00 needle, nozzle for iwata spray gun tonight out of UK 50% of the price than buying locally
 

bjf66

Well-Known Member
Joined
Apr 11, 2021
Messages
909
Reaction score
1,245
Points
93
Location
Mt Martha Vic 3934
Members Ride
VN HDT Aero
You might find this interesting

good video clip
back machine and weight saving
My existing valves weigh:
inlet 1.94: 122 grm
exhaust 1.6: 105 grm

Milodon Megaflow:
inlet 2.05: 118 grm
exhaust 1.6: 108 grm

Street valves:
Inlet ?
exhaust ?
 
Top