Does there exist a manifold to replace the constrictive HF manifold.

Im currently running a HF manifold with a dsm adaptor plate, and a 14b turbo...

I'd like to step it up, and run a better manifold, but not have to re'do my downpipe configuration.

 

i think they hf mani flows ok. if you're not looking for huge hp numbers then i'd just stick with it.

 

if you make a y7 precat like mine it might keep the piping kinda the same, i doubt it wont needs any modification though. not sure how much better the y7 flows but the ports match my z6 already and they direct it more at the turbo then out and down

 

port the hf and it will be fine.
is your adapter plate chamfered? If not, take the die grinder to that also.

 

yea, its a bmcrace plate... and its port matched.
Im so far happy with the manifold, but have always been under the assumption that it was a point of restriction.

 

I would look toward your 14b first.

I'm going to run a ported HF and an adapter plate with a GM9, shooting for 400 whp on my built z6.

 

use the hf mani with the #3 stamped on the runner. thats the largest you can get, then port it.