Apart from part numbers, s there any or much difference between the EFI cast iron heads from VL - VT?
Factory VL - VT 304 EFI heads
Started by
_CHOPPER_
, Oct 23 2010 12:16 AM
18 replies to this topic
#2
_gtr-xu1_
_gtr-xu1_
-
- Guests
Posted 23 October 2010 - 12:20 AM
VN group A heads differ with large D shape exhaust ports
#3
Struggler
-
- Members
-
- 2,426 posts
Forum Fixture
- Name:Andrew or AJ
- Location:Canberra A.C.T.
- Car:UC Sedan
- Joined: 08-November 05
Posted 23 October 2010 - 09:25 AM
The combustion chamber also evolved over the years. I think there are 3 different shapes.
#4
_sshatch355_
_sshatch355_
-
- Guests
Posted 23 October 2010 - 09:55 AM
vn combustion chambers
vt combustion chambers
vt combustion chambers
#5
MRLXSS
-
- Members
-
- 12,415 posts
The Render Garage
- Name:Matt
- Location:Upwey, Melbourne
- Car:355 LX Hatchback, DeLorean DMC-12, LX SS Hatch, VY Cross8 Crewman
- Joined: 09-November 05
Posted 23 October 2010 - 12:16 PM
What are the part number differences for the heads?
#6
_CHOPPER_
_CHOPPER_
-
- Guests
Posted 23 October 2010 - 11:08 PM
The combustion chamber also evolved over the years. I think there are 3 different shapes.
But did that really make much of a difference?
#7
_rorym_
_rorym_
-
- Guests
Posted 24 October 2010 - 08:00 AM
Looked at this doing my car...VN-VS have 63cc chambers and VT on had 56cc off memory.
R
R
#8
_CHOPPER_
_CHOPPER_
-
- Guests
Posted 20 September 2012 - 02:02 PM
The combustion chamber also evolved over the years. I think there are 3 different shapes.
But did that really make much of a difference?
I have been patiently waiting for nearly two years now, can somebody answer this?
#9
View GaragePosted 20 September 2012 - 03:23 PM
If you look at the specs over the years you'll see small rises in compression, the differences in combustion chamber size mentioned above contribute to this (56cc VT is pretty close to HQ so you've gone from somewhere around 8:1 back up to 9:1). At the end of the day though, if you're doing something custom as most are then it doesn't matter too much what you start with.
#10
mr5000
-
- Members
-
- 3,455 posts
chief break-everything
- Location:melbourne
- Car:77 lx 4door
- Joined: 08-January 06
Posted 21 September 2012 - 08:15 AM
i no vt heads arent the best for major porting alot of guys prefer the vn type heads i think the group a heads are best out of box but if your getting them ported nothing wrong with standard vn heads
#11
_CHOPPER_
_CHOPPER_
-
- Guests
Posted 22 September 2012 - 02:12 PM
So if the VT heads have the smallest chamber, then I shall casually chase up a pair of them.
#12
_LH8VD69_
_LH8VD69_
-
- Guests
Posted 22 September 2012 - 09:49 PM
So if the VT heads have the smallest chamber, then I shall casually chase up a pair of them.
Wouldnt a bigger chamber = better? .... Just asking as I'm still looking at these options.
#13
Posted 23 September 2012 - 06:34 AM
Depends on the rest of your engine and what compression ratio you want; for example if you wanted to run flat top pistons then the smaller chamber heads might better suit a stock stroke whereas the bigger ones might be better for a stroker
#14
ACJ
-
- Members
-
- 197 posts
Forum Member
- Name:adam
- Location:south of Perth
- Car:LH
- Joined: 26-November 08
Posted 23 September 2012 - 08:57 AM
As time goes on we usury get better. So as the cars got more power the heads got tweak a little bit more.
VN 5L =165kw @ 4400rpm Compression Ratio: 8.4:1
VT 5L = 179kw @4800rpm Compression ratio: 8.8 : 1
VT 5.7 = 195kw @ 5200rpm
GTS-R 215 kw @ 4800rpm compression ratios 8.85:1
I think the VT head would be the pick of heads if you are not going to port exc. 308 or 355 with a cam and you well be looking for a bit of compression any way.
If you want over 450 hp and you want to ports, the head man will make good power out of VN or VT heads.
At the end of the day you will proberly speen close to $3000 for good heads. So I would look at after maket heads like COME racing but you will also need to spend more money on the rest of your motor for a good resalt.
COME Racing 2010 VN-VT alloy heads...590+hp out of the box complete...$3500.00 a pair.
VN 5L =165kw @ 4400rpm Compression Ratio: 8.4:1
VT 5L = 179kw @4800rpm Compression ratio: 8.8 : 1
VT 5.7 = 195kw @ 5200rpm
GTS-R 215 kw @ 4800rpm compression ratios 8.85:1
I think the VT head would be the pick of heads if you are not going to port exc. 308 or 355 with a cam and you well be looking for a bit of compression any way.
If you want over 450 hp and you want to ports, the head man will make good power out of VN or VT heads.
At the end of the day you will proberly speen close to $3000 for good heads. So I would look at after maket heads like COME racing but you will also need to spend more money on the rest of your motor for a good resalt.
COME Racing 2010 VN-VT alloy heads...590+hp out of the box complete...$3500.00 a pair.
Edited by ACJ, 23 September 2012 - 08:58 AM.
#15
_CHOPPER_
_CHOPPER_
-
- Guests
Posted 23 September 2012 - 02:54 PM
Wouldnt a bigger chamber = better? .... Just asking as I'm still looking at these options.
It's easier to make a small chamber head larger than the other way round. IF I do go down this path and use the cast iron EFI heads, it would at most run a 355 stroker and a mild cam. Just a nice stret engine. If I was chasing big HP, I wouldn't use ANY Holden block.
#16
Uncle Chop Chop
-
- Members
-
- 1,409 posts
Grumpy Old Man
- Name:John
- Location:Vic
- Joined: 19-November 12
Posted 26 March 2013 - 08:04 PM
It might be a bit of an old thread, but does anybody know what numbers are cast into these heads? I'll probably be getting a pair next week, so it would be handy to know which is which.
#17
_Baronvonrort_
_Baronvonrort_
-
- Guests
Posted 27 March 2013 - 04:15 PM
A good thread on aussie V8 about the VN onwards heads including YT and Come alloys by HPE Pete who does a lot of porting on these heads he posts plenty of photos to show his handiwork which will help you identify what you have or want.
http://www.aussiev8....2-vn-heads.html
#18
Uncle Chop Chop
-
- Members
-
- 1,409 posts
Grumpy Old Man
- Name:John
- Location:Vic
- Joined: 19-November 12
Posted 27 March 2013 - 08:01 PM
I think it will take me a while to read those 37 pages, but thanks anyway.
#19
_pinklx_
_pinklx_
-
- Guests
Posted 28 March 2013 - 11:23 AM
ive only ever seen two differant casting numbers for efi heads allthough ive found three listed, the walkinshaw #92060145.which ive never seen, actually all the walky heads ive seen have the same casting as the vn thro to vt heads casting #92060019 in these heads vn to vs series 2 had 64cc chambers and are good for porting and the vs series 3 and vt had 58cc but are thin castings and are no good for going large.
the other number is #92060757. this is the vn group a head. totally differant castings but as far as i can tell same chamber shape and size as regular vn. the exausts are d shaped and the intakes are larger with alot more meat in the roof area, u can actually raise the intake runner so much the injector notch is completely gone. also the decks are way thicker. ive got a set that have had around 100 thou taken off them and have 46cc cambers after the were polished. these are the best efi factory heads u can get.
if i had to get a set of heads and keep costs low i would grab a set of stock vn heads send them to pavtek with directions for watever cc chamber i wanted, run them through the full race port cnc program, throw him a 1000 bucks and have heads that flow around 600hp. cheap really.
1 user(s) are reading this topic
0 members, 1 guests, 0 anonymous users
