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Streetable 304 build

Loomesy

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Hi Guys

Just had my Vk returned from paint and am starting to look at the engine build. Will be running BW78 diff with 3.08 gears. T5 gear box.

What I want to know is if anyone could recommend a good combo to suit the above. I will be running a torque power manifold and Holley snipper injection. Vn heads and FT cam. Want a tough street engine that can hold its own in the 270-300hp range.

Any advise would be great
 

shane_3800

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Get some edelbrock heads and maybe go a 3:75 diff yea both those are more expensive but are good value imo.
 

shane_3800

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Money is better spent elsewhere. Those heads aren't required for a tough streeter.

You can run one point extra compression and they improve power everywhere across the curve.
Both those facts see you a massive net gain in torque from 1000rpm to the torque peak which is exactly where you want power in a street car.
 

someguy360

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You can run one point extra compression and they improve power everywhere across the curve.
Both those facts see you a massive net gain in torque from 1000rpm to the torque peak which is exactly where you want power in a street car.

$400 worth of Flat tops and mild machine work to a set of VN heads (which he already has) would get you better compression result cheaper.

The price of aftermarket alloy heads for Holdens are off the charts, and will completely blow out a basic street engine build cost, unless your after huge numbers it's not worth it imo.

VN heads will easily flow 400hp.
 
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Loomesy

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Cheers for the reply fellas. Would agree with the diff change but probably only to 345 as it will do some highway work. It won't be a daily driver, only on the odd weekend. Yea going to get heads machined, any info on piston recomendations, compression ratios, cam specs and weather I should run stock crank and rods or upgrade.

Cheers
 

shane_3800

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$400 worth of Flat tops and mild machine work to a set of VN heads (which he already has) would get you better compression result cheaper.

The price of aftermarket alloy heads for Holdens are off the charts, and will completely blow out a basic street engine build cost, unless your after huge numbers it's not worth it imo.

VN heads will easily flow 400hp.

You don't understand what I wrote.
Yes you can increase compression with flat tops but ping will limit how far you can go. Alloy heads can go from 10.5:1 to 11.5:1 without any ping as the alloy dissipates heat faster.

I looked into this and even the edelbrock heads outflow from the factory a set of ported VN heads.
VN cast iron heads actually flow fairly poorly.

Just because a head can make 400hp peak gives you very little idea on how that head will react below the curve. Increasing compression gives you an increase throughout the curve. Better chamber design gives you a better flame front leading to you being able to bring in more advance earlier again leading to improvements accross the entire curve not just a peak where you have to rev excessively high to reach that peak.

Also edelbrock heads are the cheapest quality head and are around 2k a head ready to bolt on
 

shane_3800

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Cheers for the reply fellas. Would agree with the diff change but probably only to 345 as it will do some highway work. It won't be a daily driver, only on the odd weekend. Yea going to get heads machined, any info on piston recomendations, compression ratios, cam specs and weather I should run stock crank and rods or upgrade.

Cheers

If you want to change pistons, rods and crank it's cheaper to just go a stroker.
355 strokers are the go.
 

Deuce

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VN cast iron heads actually flow fairly poorly.
He did say 'with port work'.
The order is for 'on a reasonable budget' so in this case I believe working the stock VN is the better choice (and I am running come590s on my 355)

OP if you go around 10:1 comp and not too crazy on the cam. Maybe 230/240 @50 and around 110 lobe sep - at a quick guess.

My 3.45 diff runs around 2100rpm on the highway - but that's with 4l60e.
What is 5th gear ratio on the T5?
 

keith reed

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The vn v8 heads are a very good head. Get them port pocketed and that is all you will need. As far as anything else goes Crow cams have a form for you to fill in and send to them and they will advise you on what to do.
 
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