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What intake Manifold Worked 304 v8?

Deuce

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Obviously I could give you many soruces of info but you'll keep brining up your info that I debunked and not listen..
Please provide more sources as offered, but please use GM HOLDEN 308/304 or even 355" in your source.
If you actualy watch Richards videos you'll realise he's tested 90% of engines out there in the performance world he even broke a land speed record with a honda 4cyl.
90% of engines, but not a General Motors Holden V8. And that is the motor we need to know about.


Yes - the rule is shorter runners promote higher HP, and longer runners promote higher Torque early in the rpm range. Simple stuff.
But air also likes straight lines at speed (or as straight as possible - hence why tunnel ram is awesome, straight, long, and plenum).
Should I recommend a high rise manifold to get runner length? Of course not, because they generally have larger cross section runners which would slow velocity and hurt low end torque, and they are also highly unlikely to fit under his bonnet.

My original recommendation was a small size single plane manifold. Because:
- fits under bonnet (OP please check before purchase)
- runners are not large
- runners are as straight as possible
- OP has decent compression so should find torque a plenty everywhere in the usable rev range
 

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Please provide more sources as offered, but please use GM HOLDEN 308/304 or even 355" in your source.

90% of engines, but not a General Motors Holden V8. And that is the motor we need to know about.


Yes - the rule is shorter runners promote higher HP, and longer runners promote higher Torque early in the rpm range. Simple stuff.
But air also likes straight lines at speed (or as straight as possible - hence why tunnel ram is awesome, straight, long, and plenum).
Should I recommend a high rise manifold to get runner length? Of course not, because they generally have larger cross section runners which would slow velocity and hurt low end torque, and they are also highly unlikely to fit under his bonnet.

My original recommendation was a small size single plane manifold. Because:
- fits under bonnet (OP please check before purchase)
- runners are not large
- runners are as straight as possible
- OP has decent compression so should find torque a plenty everywhere in the usable rev range

In 90% of applications cross section is not an issue because heads and intake are based off the gasket. Yes special race heads and manifolds will increase cross section but we're all adults and we all know that we're talking about generic off the shelf bolt on parts in this thread.

Re: The holden V8 thing. If you see a trend in a 350sbc, 350w, 350c, BBF, BBC, BB hemi, BB wedge, 455olds, buick V6, modern hemi, LS1, LS3, 4.8LS, ford mod motor, Ford cyote, Ford barra.

You can sure as sh.t bet it's going to be a trend in a holden V8.
Over the last 12 years of reading Tony Knights posts one thing he always says is it dosent matter what brand the engine is as long as you get the heads to flow X it will make X power.

The short block has no bearing on power other than displacement and a slight influence depending on the piston face other than that the short block is just displacment.

So you get a holden head to flow 220cfm with 65% exhaust and compare it to a SBC head that flows 220cfm with 65% exhaust and they both have 355ci the engines with similar intakes and the same cam, same comp will make the same power. Don't believe go ask TK him self he's always on forums.
 

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TK383;494809 said:
Yeah, I prefer width over height - spreads the flow over the width of the turn better. I pretty much maxxed out the width of the turn & just used height to get to the cross section I wanted, testing I did on a junk head said the port would prefer width over height to remain stable at high lift/high depression.
They were still going strong at .800" lift but I ran out of travel on the valve opening jig to go any higher - the way they were behaving methinks they would have gone out to .900" lift & still gained. Which will make them very stable at the higher depressions seen on a running engine - she'll carry well above peak power.



If peashooter is the biggest that'll fit in a casting them you have to make do - cammed right a smaller port can work, dependant on application. But hey, VN's will go pretty big, so big ports & moderate cams give the best torque spread whilst keeping a strong top end.
Pro-paw would be too big, this engine will get a ported harrop.
TP really need to make a manifold between the little paw & the pro paw - harrop sized or just a little bigger. The harrop is not as good a design as the TP stuff, but it is closer to the right size for a stomper 355.
May have to talk to Craig about that, the original TP single (called little paw now) doesn't cut it when aiming over 550hp. Back when it was designed guys building tuff 355's were shooting for 500hp, which it does very well with a strong torque curve, but 500hp is so 2009 now.
 

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HPE PETE;494894 said:
did these ones a couple of months ago i wouldnt call them ported as **** but they are still a nice set of heads, they are for a mate thats building an engine for his mate with a camtech 258 264 108 or 109 lsa VK commy

it was sort of a budget job as we werent starting from scatch more of a make it work job, they were originally ported by jack bros and flowed 268cfm with a 2.02 i dont have finished product pics but heres a couple of them getting done

172cc runner

port height @ pushrod 2.050
port width @ pushrod 1.244

CSA @ pushrod not including radius 2.550"

we put a 2.055 1.625 ferreas in them

this is with the comp plus ferreas we used in the heads which arent the best flowing valve for a holden head, with holdens the cheap ones flow better
.100 70.4
.200 143.5
.300 206.5
.400 238.6 490hp
.500 270.3 556hp
.550 277.4 570hp
.600 291.2 599hp
.650 297.3 611hp
.700 301.1 619hp
.750 301.0 619hp
 

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TK383;498100 said:
cava - I wouldn't have an 'ideal' cfm figure in mind, I'd have an ideal port size, shape, taper, bowl width etc etc etc in mind & whatever that port flowed would be what I'd want!

I do SFA flow testing, more often than not on heads I'm familiar with I'll only flow them once they are all done & ready for final assembly - & even then only coz most customers will want the numbers.
On stuff I don't know well I will spend some time back & forthing to the bench to find the shaping & seat angles that'll make it happy, but even then it's a rare occasion that I'll have to chase it. Annoying when you gotta chase your tail on a port.
Lately only LS stuff has made me think twice (or 3 times) - they are a PITA to get right, but got it sussed now.
 

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The short block has no bearing on power other than displacement and a slight influence depending on the piston face other than that the short block is just displacment.

So you get a holden head to flow 220cfm with 65% exhaust and compare it to a SBC head that flows 220cfm with 65% exhaust and they both have 355ci the engines with similar intakes and the same cam, same comp will make the same power. Don't believe go ask TK him self he's always on forums.
Different deck heights = different rod length = different rod angles = different cam specs and different ign timing = different results.

Yes sbc and gmhv8 are close. But if you want to make statements how everything is the same, I will remind you that every small difference adds up to the different results EVERY ENGINE will get.
 
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