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 Stock intake limitations

gtrboyy

Well-Known Member
Joined
Jan 25, 2006
Messages
3,068
Reaction score
1,443
Points
113
Members Ride
vt ss & lc gtr
Banana manifold has been done to death you don't think dudes were silly enough before you to spend hundreds of hours on the damn things or crazier blokes who spent thousands wanting best results just to say they proved everyone else wrong...

Best reslts were extrude honed starr manifold or larger throttle body like come item or ls1 item with opening moved to the front & maybe little grind work to open the entry.

There are so many flaws with banana manifold if maximum performance is the goal...different story once add boost though.
(lost count of people who tried even greenfoam threads,starr performance,street com forum & probably peeps from this forum too)

Even comparing walky or group a manifolds versus single plane was done to death & yes single plane was broader torque spread by better straight shot to valves...which is basically what touring cars similar to group a manifolds without top on it.

Again got no idea what it is you're trying to achieve...dyno figure,track car,drag time or just street car.

ps opening up runners won't do jackshite when massive open space in middle of manifold with uneven airflow distribution...highest velocity blows straight past front 2 cylinders because they too close to opening & by time air does hit rear cylinders it has filled open cavity & slowed down or hot by heatsoaked manifold.
 

afstruct

Well-Known Member
Joined
Dec 10, 2015
Messages
1,179
Reaction score
1,124
Points
113
Location
Warners Bay
Members Ride
HSV VS Maloo , 2002 Monaro
Also you guy's are saying it can't be done but that just doesn't sit right with me.
If humans can build pyramids surley where there's a will there's way.
=
And don't get me wrong = I'm with you all the way!! !!!!
But after reading this has me thinking = join the majority and would love to maximize = but = cut my losses=
And I have a star manifold !!!!!
 

shane_3800

Well-Known Member
Joined
Aug 13, 2011
Messages
2,901
Reaction score
1,041
Points
113
Age
33
Location
places
Members Ride
vr commo
Banana manifold has been done to death you don't think dudes were silly enough before you to spend hundreds of hours on the damn things or crazier blokes who spent thousands wanting best results just to say they proved everyone else wrong...

Best reslts were extrude honed starr manifold or larger throttle body like come item or ls1 item with opening moved to the front & maybe little grind work to open the entry.

There are so many flaws with banana manifold if maximum performance is the goal...different story once add boost though.
(lost count of people who tried even greenfoam threads,starr performance,street com forum & probably peeps from this forum too)

Even comparing walky or group a manifolds versus single plane was done to death & yes single plane was broader torque spread by better straight shot to valves...which is basically what touring cars similar to group a manifolds without top on it.

Again got no idea what it is you're trying to achieve...dyno figure,track car,drag time or just street car.

ps opening up runners won't do jackshite when massive open space in middle of manifold with uneven airflow distribution...highest velocity blows straight past front 2 cylinders because they too close to opening & by time air does hit rear cylinders it has filled open cavity & slowed down or hot by heatsoaked manifold.
It will be driven on the street
=
And don't get me wrong = I'm with you all the way!! !!!!
But after reading this has me thinking = join the majority and would love to maximize = but = cut my losses=
And I have a star manifold !!!!!
Yes but the issue with the Starr is it never solved the runner restriction issue.
From the Accufab link I posted the CFM is there with a 70mm TB.
Maybe the 90mm plus TB slows the air down past the first two entries like how GTR boy was ralking about?
But I could make a triangle plenum to sort that issue out anyway.
 

shane_3800

Well-Known Member
Joined
Aug 13, 2011
Messages
2,901
Reaction score
1,041
Points
113
Age
33
Location
places
Members Ride
vr commo
I also like how I'm objectively asking questions of "how can we do" instead of the rhetoric of the internet "you cant do"
 

afstruct

Well-Known Member
Joined
Dec 10, 2015
Messages
1,179
Reaction score
1,124
Points
113
Location
Warners Bay
Members Ride
HSV VS Maloo , 2002 Monaro
I seriously
wish I could help = because it would help me !!!!!
 

ephect

Donating Member
Joined
Jul 27, 2006
Messages
5,100
Reaction score
6,074
Points
113
Location
Melbourne
Members Ride
VS Acclaim V6
If I understand this correctly, you can go from 41mm to 47mm, if the walls are 5mm. You could only go 44 safely with 2mm wall between each runner.
 

immortality

Can't live without smoky bacon!
Staff member
Joined
Apr 15, 2006
Messages
17,252
Reaction score
6,624
Points
113
Location
Sth Auck, NZ
Members Ride
HSV VS Senator, VX s2 Calais S/C
As I mentioned earlier there was a mob that did extrude honing of these manifolds, they had moderate gains but I dont remember anything along the lines of 500hp. So good on you for trying this mental exercise but in all honesty this has been tried by smarter people than us with much more money and they decided Making a new manifold was a better option.
 

losh1971

Well-Known Member
Joined
Jan 17, 2010
Messages
12,336
Reaction score
5,617
Points
113
Location
North Tas
Members Ride
The Bus
@shane_3800 instead of talking about it for the next two weeks, why not just give it a go and see if you even have success porting the manifold?
 

gtrboyy

Well-Known Member
Joined
Jan 25, 2006
Messages
3,068
Reaction score
1,443
Points
113
Members Ride
vt ss & lc gtr
For what afstruct wants only real difficult part is camshaft choice & making sure it's all built with matching parts to suit his purpose...basically stroker with decent comp & mild cam limited by starr manifold which is ok as probably cares more about low-mid range torque,reliability & not about power falling off in 5k range....stally & diff gear choice will get most out of it.

Below is modern day improved version of banana manifold by Bliss...gave me a semi-chub checking it out couple years ago.

1631699900472.jpeg
 

gtrboyy

Well-Known Member
Joined
Jan 25, 2006
Messages
3,068
Reaction score
1,443
Points
113
Members Ride
vt ss & lc gtr
Ls1 throttle body mounted to front will help decent amount & suppose matchporting runners to heads...after that very small gains for stupid amount of hours required.

Of the dudes who chopped up banana manifold they were nuisance to weld up due to being low quality aluminium or porous/impurites.

Hit up Chubby for info or better yet [email protected] Performance Tuning as he built & tested several versions trying to get most out of 304 setups

Be easier to wait for lowe fab adaptors then throw on ls6 manifold...ugly as but probably work better.
 
Top