custom turbo plenums

[Crucible]

Are they worth the extra money or not? Compared to using a standard N/A manifold will there be a significant gain in power or will it only flow as well as the head. Has anyone dynoed before and after fitting a custom job? drifter4ag?,crnkin?. Also what would be the ideal way to fabricate a custom manifold for maximum flow?. Im looking at getting one made but just not certain it would be money well spent if a standard manifold will deliver near the same performance....

tnt

[crnkin]

1. how much power do you want?
2. how much money you got?

[IH8TEC]

or will it only flow as well as the head.
tnt

i reckon thats your answer there, and 'some' seem to think that most 4agte's wont outflow the NA manifolds,

[crnkin]

or will it only flow as well as the head.
tnt

i reckon thats your answer there, and 'some' seem to think that most 4agte's wont outflow the NA manifolds,

exactly

[soopachargen]

have you ever looked inside an N/a manifold? They have separations etc that look like they were designed for a reason. I dont know if this reason is N/A specific, but after taking the throttle body off mine it made me wonder about whether an aftermarket one would really be as good. I hope you know what i mean. I kinda makes sense to me:P

[crnkin]

Ive never seen (just me) or heard of anyone getting an entirely new manifold for a single throttle body 4age, the stock ones are pretty good if port matched, ive seen dyno sheets of 420kw atw with a stock manifold.... dunno what the difference would be aftermarket, looks maybe? wank factor?

[QikStarlie]

runner lengths, runner diameter, bell mouths, plenum size, and a few other tricks will certainly make a diffrence in power and where it is made. make it wrong tho and you'l loose power. bit more care needs to be taken when playing with the intake than the exhaust side

[Crucible]

1. how much power do you want?
2. how much money you got?

Im Not after huge numbers 180 (+-) kw would be ample in my situation as Its a daily driver and afterall is FWD. I had a mate offer to fabricate a manifold for me but just wasnt sure the best way to fabricate it for size,flow etc. Im going to use an N/a one now as Id rather spend money elsewhere and its not really nessesary for what im after.

I know with N/A v8 manifolds a dual plane will give good bottom end whereas a single plain is more suited for upper end, always wondered how custom 4cyl plenums are set up internally and was just curious to know what the ideal runner,plenum setup would be in a Turbo application? Bazda has however given me a few good pointers......

Cheers

tnt