VT 5 Litre manifold mods and results

[merlinnn]

Hi Everyone,

I have been searching everywhere in relation to banana mods and whilst finding lots of how to and what some have done, I can't find any actual dyno results such as before and after.

Does anyone have any or links to where someone has documented the mods and backed them up with some real life results?

Cheers

 

[Nut Kracker]

For example......
http://forums.justcommodores.com.au/vt-vx-vu-wh-v2/228568-nut-krackers-1997-vt-ss-lots-pictures.html

 

[merlinnn]

Thanks Nut Kracker. Do you have any more info on your manifold? Was it custom built from scratch or modified existing? Runner length, plenum size etc?

What gains would you attribute to the manifold as your beast is obviously making some serious power for a 5 litre?

 

[_R_J_K_]

Have a gander at extrude honing, some companies should be able to provide you with numbers. I know somebody who decided to go that route on their cammed Holden 5.7L with promising results (but none that are really documented). The company also welded a rod in front of the no. 5 runner as I believe it stops it leaning out? Somebody more familiar with the bananas will know why they did this.

Typically you won't get a before and after on just the manifold alone as most people do a bunch of other stuff at the same time.

 

[merlinnn]

Thanks for that. I guess I'm trying to weigh up the outrageous cost of an after market unit, for which I don't think it warrants. At this stage I just want to play with bolt on upgrades before sourcing a complete motor for a rebuild.