To manifold or not to manifold?

[Dark Blue Mark]

I have a Gruppe M on the way, and already have a Spoon back box.

What im not sure on is whether to go for a manifold and leave rest of the exhaust alone, or to go for the Spoon decat and mid pipe and leave the expensive / time consuming manifold alone.

I plan to get either choice K Pro'd and would appreciate some thoughts on whether id not see much difference with my non manifold plan. Or rather, is the manifold an essential part of mapping these cars?

Its clear that is does do a lot, but im just looking to see where I owuld be without an aftermarket one. Main reason os the fitting / removing hassle.

Discuss

 

[The Mofo]

From what I've read on here the manifold is the most restrictive part of the exhaust. You would get better gains by replacing the manifold and having the standard exhaust system than having the standard manifold and uprated exhaust.

Personally the Island has no MOT so I have no problem with replacing the manifold, but if I lived in the UK I would still get a new manifold, in my view it's worth the hassle.

 

[BadBadtz]

Manifold is supposedly the most restrictive part of the system so depends on what type of gains you are looking for

 

[AdrianK]

If your changing the manifold, IMO id only do it at the same time as having a kpro done, lots of people say the car runs lean to a degree with a manifold on, and you wont get the full benefit of its large cost unless your kproing!

So ask yourself, do you want/can you afford a mani and kpro, if yes, get them both if not get neither.

 

[Evs]

K-Pro will make you a lot of mid-range whether you have an aftermarket manifold or not. Worth doing on its own imho.

An aftermarket manifold will make more power again (and more noise), but I wouldn't change that on its own without sorting the ECU as well. If you remove the cat then you might find it too loud overall with the N1 BB.

Changing manifold and ECU gives you good power, but if it's either-or then tbh I'd just get the ECU.

 

[Dark Blue Mark]

Cheers all.

Adrian, I will KPro either way, its just whether to do the manifold or just the decat back...

Wonder if anyone has KPro results with and without manifold? I guess not eveyone changes it so guess there are some dyno's out there...

 

[Dark Blue Mark]

Thanks Evs, useful reply too.

 

[AdrianK]

As i think people have said on here before a good setup with kpro is the spoon 4-2, std cat section, spoon b pipe and std backbox, gives good gains and is not overly loud.

Believe me the manifold makes the car a lot louder, i have heard spoon N1 with a manifold, and mine without is a massive amount quieter, so unless you want to wake the dead, think twice about replacing the whole mani and keeping the spoon!

I personally wont be changing the manifold parts, ill get kpro in the winter if i can afford it, and stick with an exhaust i like.

 

[Evs]

Wonder if anyone has KPro results with and without manifold?

Been done a few times now tbh

http://www.itr-dc5.com/forum/viewtopic.php?t=4792

HTH

 

[mikegsi]

if your gonna decat then get k-pro, imo if you plan on doing all the mods at one point then save your money and do them at the same time, you WONT be dissapointed!!!!