HKS Cast iron low mount manifold, any good??

[NZM.031]

hey guys,

been looking at replacement exhaust manifolds for my RB25det. i keep seeing the HKS cast iron low mount manifolds for sale.

are these bad boys any good?? must be as heavy as the stock one though, should i save up for a stainless manifold??

does anyone know of a good low mount setup that doesnt have any pipework for an external gate??

do they sit the turbo in the original location??

all the stainless ones i see have pipework coming out for an external wastgate, im want to keep it internal unless i go high mount. the manifolds are all really expensive too.

any help would be appreciated

cheers

Linton

[Cefiro_PWA]

Stainless steel and exhaust systems is a bad mix.

Cast is definatly better.

Go for it... i got one its nice.!

[geordie]

You can get low mount stainless with no external gate pipe from www.tuneagent.com - about $550 i think

[R31Nismoid]

Stainless steel and exhaust systems is a bad mix.

Cast is definatly better.

care to go into why that is?

[Memph]

only think i know about stainless steel as it oxidises like any other metal at temps of around 300 - 350+

So considering most people chose it due to it being rust proof, thats sort of not true..

lol but from the looks of the HKS cast manafold, looks like a stock one with a flange for a wastegate. doesnt look like anything special. yet theres a good chance i have no idea

[Cefiro_PWA]

care to go into why that is?

Reason being, cops dont like bling, SS is bling, and thats all it is.

crap cooling properties and its NOT rust proof..

Cast is used by HKS not just for RB/SR manifolds they even use them on there DRAG RACE CARS AND CIRCUIT CARS!

SS is cheaper and dodgey IMHO!

i dont know tech bits about it.. but who cares...

[Cake]

cast = win

ss also more prone to cracking

can't go wrong with the cast iron low mount setup NZM.031 if you're going to use an external wastegate

[NZM.031]

thanks guys. ive put a s/s manifold on a 180, turned blue, then purple, then gold, then brown and is starting to rust in the crevices, no dramas yet though, and its been almost a year....

the HKS is a much better design than the original, but does it sit the tubo in the same place?

i may go external, but thats a long time away...my turbo of choice at the moment is a 2835 pro with internal gate.

cheers

Linton

[TTT]

have you read the thread on here about the extrude honing of the stock manifolds?

the thread title is:

'Stainless or factory exhaust manifolds, results inside.'

interesting read for you.

[Sydneykid]

What the others have said plus the rear low mount is better for handling, lower C of G and more rearwards weight distribution.

[BHDave]

thanks guys. ive put a s/s manifold on a 180, turned blue, then purple, then gold, then brown and is starting to rust in the crevices, no dramas yet though, and its been almost a year....  

the HKS is a much better design than the original, but does it sit the tubo in the same place?

i may go external, but thats a long time away...my turbo of choice at the moment is a 2835 pro with internal gate.

cheers

Linton

The hks manifold doesn't sit the turbo in the same place. It is actually sitting lower and slightly further back. Also it is bottom mount (for lack of a better term) rather than side mounted as the stock manifold.

The provision for an extenal gate on the manifold can be blocked simply by using a hks 38mm ex gate gasket gasket and a thick steel plate bolted in place

Because of the change in position you will have to fabricate a new compressor inlet, new compressor outlet, new oil and water lines, new oil return, and new dump pipe (and possibly front pipe too). The manifolds look a million times better than the stock cast item, with individual runners rather than the factory log design.

I'll have one on my car in the not too distant future. It's sitting in the garage atm.

[dangerous_daveo]

Look at getting a steampipe one made up too. At least get a quote to get an idea of price.

A thing that hasnt been mentioned is... On the exaust side of things heat isnt a full on bad thing, hotter air is thinner, thinner air moves faster. Stainless doesnt hold in the heat as good, so it gets in to the engine bay (=bad) and doesnt stay in the pipes meaning cooler air in the pipes (= also not so good).

So Id say steampipe or cast. Have a look, and then if you get the cast one, have a look at extrusion honing that as well.

[NZM.031]

ok, i dont want to have do do that much work...i just want a manifold that i can bolt on to the standard turbo, as mine is hiflowed and i like it just the way it is. anyone know of a decent manifold that keeps the turbo in the same position.

cheers

Linton

[Cefiro_PWA]

What the others have said plus the rear low mount is better for handling, lower C of G and more rearwards weight distribution.

We should all start buying FC/FD RX-7's if that were the case :band: