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Inlet or Exhaust Manifold Upgrade?

1761 Views 11 Replies 6 Participants Last post by  JBS-Sales
as above is this worth doing on either?

if so, any links?
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I havent heard of inlet manifold upgrades, unless you're going huge turbo. APR do one as part of their stage 3 kit I believe.

Exhaust manifold is more common although lots on here have got 240 bhp with the standard one, just non-standard everything else! I remember seeing that JBS advertise their uprated manifold alone on an AUM / K03s with accompanying remap will give 225 bhp, although havent seen it on any build threads so cant link sorry.

not worth doing then? just looking for a mod to do thats all...
Which engine mods do you currently have? I've played with a few and can give my 2p on what might be good to do next if you want...
4 bar, turbo back exhaust, carbonio, forge dv, turbo hoses, tip, short shift kit, upgraded smic.
I cant see the point in upgrading either. Its the turbo being so small that is the restriction and not either of the manifolds.

For the inlet I would possibly look at a Phenolic Insulator Gasket

The biggest issue with aftermarket exhaust manifolds is the fit is truely awful and also the quality of them is poor and very prone to cracking except the JBS item that seems to be the exception but Badger5 recorded on increase in power by fitting it just a small improvement in spool. Badger5 are offering midly ported and polished standard manifolds as a cheaper alternative
Pointless doing in all fairness.
Sounds like you've got performance mods pretty much covered then! Have you had it mapped and if so what are you getting?

If you're struggling to get the magic 240 then maybe its that the SMIC still isnt cutting the mustard.

From all that I've seen, 240bhp is about the limit of the K03s, so even with a better flowing exhaust manifold you wont see anything higher than that.

Perhaps hybrid K03s / k04-001 is the next stage. They should both be a straight bolt-on without needing to change other bits (like you would have to with a K04-023 from a LCR/S3/TT225.

270bhp K04-001 hybrid build:
am already looking down that route but you need about 1k to do it fully, ie turbo then hybrid it, remap and 380cc injectors
Sounds like you have got the most out of the k03s.

All depends how much power you want really.

240bhp from a k03s is going to need a very healthy engine and map....but then again....peak bhp means on getting a very quick map through acceleration.
I would think the manifold would be very useful on a hybrid ko3 turbo. The standard one is very restrictive.

But they arn't cheap - and they dont have a good history of being reliable (not any of them).

The JBS K03 OEM cast manifolds has had no reported problems with cracking or warping as many of the competitors products have!

We have recently brough the prices down on these to a bargain, please see the website link below:-

Any question or queries about this,or any of the other products we list on the website, please feel free to ask!

Seb Hampson

Parts/Sales Advisor
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