308 want more power

[chrisso 82]

Hey guys thought i would start a thread on how to get more POWER from THE HOLDEN 308????????

My 308 was rebuilt 2yrs ago and sat in a mates shed till i bought it!!!!!
Its just stock at the moment apart from the 650 holley, Extractors and gilmer drive setup,

What do you guys recommend doing to get some more POWER from it!!!!!!!!!!!!!!

[ari666]

put the quaddy back on it would be the first thing.

whats your budget?

[Zeussy]

put the quaddy back on it would be the first thing.

Knew you would say that

6/71, Cam, fuel pump, lol,

[chrisso 82]

Hey zuessy would love a supercharger everyone would LOL
Im just after a bit more go on a budget of course
looking to spend around $1500 to $2000 mark
thats all the minister of finance would allow (WIFE) HA HA!!!!!!!!!!!

[Clutchy]

cam and head work get it breathing a bit betterto warent havin the 650 on it.

[delcowizzid]

quaddys supposidly flow 750 cfm

[DANNY8]

I rekon the best bang for ya buck is changing to VN heads. Here's some average prices, plus a few prices which I got stuff for.

VN heads - $200
Intake - $900 (around that, apparently Torquepower is the one to go for...I'm using a shitty Procomp and so far it's actually been good...didn't even leak! Got it for $150 second hand)
Cam 2 suit EFI heads - $220 (I used a Crane Blueracer, from OG Speed Shop in Adelaide)
Crane anti-pump lifters - $145 (OG in Adelaide)
Extractors to suit VN heads in VB-VK - $600. I used Castle Headers, as they were the only ones to make them to suit manual steering. Plus they're bigger pipes then Pacies. Apparently Pacies do fit with manual steering tho, even tho they say they don't. Ask RVK355.

That's roughly about it.

In our race car we have a 308 which has a stock bottom end and the only performance mods are Yella Terra bathurst heads, Dynotec cam, Edelbrock Performer manifold and a 600 Holley vac sec carby. That made 146rwkw. My VK has a 308 with a stock bottom end, and the only performance mods is a cam (similar to the cam in our race car), VN heads, Procomp manifold, 750 vac sec Holley and that made 174rwkw with it leaning out. The only major difference between the 2 motors is the heads, intakes and carbys. With that said tho, I'm sure our race car is alot better down low, where the VK is better higher up in the revs. Prolly coz the race car is lighter, and it's runnin a dual plain manifold, where as my VK is a single plain.

VN heads is definitely the way to go!

[chrisso 82]

Cheers danny great answer mate but have you heard of anyone keeping the stock heads and gettin them to flow better ???
i have my eyes on a high rise manifold up here that suits the standard heads which i can get for cheap!!!!!!!!!
WHAT TO DO!!!!!!!!!

[Clutchy]

quaddys supposidly flow 750 cfm

Yeah I know that but im only goin on my old vk it had a 650 dp on it and when I put a quaddie on it I think it was better with the quaddie. (my 308 had a bit of work but.)

[DANNY8]

Cheers danny great answer mate but have you heard of anyone keeping the stock heads and gettin them to flow better ???
i have my eyes on a high rise manifold up here that suits the standard heads which i can get for cheap!!!!!!!!!
WHAT TO DO!!!!!!!!!

I think someone posted an article on here about carby heads versus VN heads. Can't remember where it is, but in a nutshell it said if ya port out carby heads as much as possible, they still don't flow wat VN heads do standard.

[Reaper]

A bad set of VN heads will still flow better than all but the best old style heads. There are plenty of them around - I'd start with ebay myself.

As for the rest - like any engine, HP is simple.

Compression - 10:1 is a nice compromise for street engines
Cam - Bigger is not always better however 10:1 compression should get reasonably large hydraulic cam to work
Heads - as mentioned above - VN style = win
Carburetter - I like Rochester carbs myself - shits over any Holley!
Intake - I have a TP dual plane manifold - excellent quality.
Ignition - Get the dizzy graphed to suit the cam/carb setup.

Reaper

[ari666]

VN heads - $200
Intake - $900 (around that, apparently Torquepower is the one to go for...I'm using a shitty Procomp and so far it's actually been good...didn't even leak! Got it for $150 second hand)
Cam 2 suit EFI heads - $220 (I used a Crane Blueracer, from OG Speed Shop in Adelaide)
Crane anti-pump lifters - $145 (OG in Adelaide)
Extractors to suit VN heads in VB-VK - $600.

all of that ^^^ i wasnt really all that surprised when you hit the kw figure danny, was pretty dissappointed that i didnt follow that route from day 1. OP, VN's are the way to go and you should easily be able to do it with $2k.

DO IT

edit* just a thought too: you may want to consider fitting a couple of cats to the exhaust system too since none of the old pollution gear will work anymore.

[chrisso 82]

Thank guys will look at the VN style heads and work out some prices!!!!!!!!!!!!

[mr j-man]

hey! do the rochester quaddys bolt onto a spreadbore edelbrock performer manifold?