exhaust manifolds

[chris CORRADO 0]

hey i am getting a CAT bypass and full powerflow stainless exhaust system fitted in a couple of weeks. i wanted to know if getting a new stainless seal maniflow will boost the juice a bit more than it would with the standard on this system.....

 

if so where can i get a performance manifold and what are the prices like on a 2.0L 16v.... also maybe a web link

 

cheers

-------

chris

[matt buz 0]

I believe awesome GTi do a manifold

 

Go to the bottom of their homepage and you will see it advertised there

£235

[davidwort 0]

I've always understood that the standard 16v manifold and downpipe is perfectly good and simply internally 'cleaning up' the cast iron exhaust manifold is all you really need to do.

All in one manifold and downpipes are great for cars like the mk1 and 2 8v GTI's but do have a tendancy to crack. If you look at the standard manifold and downpipe it has quite a bit of flexibilty built in.

IMO, not worth the money on a 16v.

 

David.

 

hey i am getting a CAT bypass and full powerflow stainless exhaust system fitted in a couple of weeks. i wanted to know if getting a new stainless seal maniflow will boost the juice a bit more than it would with the standard on this system.....

 

if so where can i get a performance manifold and what are the prices like on a 2.0L 16v.... also maybe a web link

 

cheers

-------

chris

[chris CORRADO 0]

What r u saying that all my proposed mods arn't good enough for a 2.0L 16v............ :cry: :cry: :cry: :cry:

[VR6 0]

I don't think he's saying 'not good enough'. I think he's saying 'could be better spent'.

[Kevin Bacon 5]

So long as steel manifolds are well insulated with thermo-wrap, they're pretty good. I've seen a Supersprint MK1 16V stainless 4 branch (specially made for the conversion) liberate 8bhp on a standard engine.

 

Iron manifolds are better in the respect that they retain heat better, which helps pull the exhaust gases out of the cylinders better, but they're quite restrictive.

 

As with everything, you get good ones and you get bad ones.

 

Kev

[dubster82 0]

ahhh. kev, you've saved me posting about this :D

 

What kind of places would i get the heat tape for exhausts? you know?

[Joe M 0]

Demon Tweeks sell it, its not cheap though. (In the motorsport catalogue, not the tuning one)

[16VG60 0]

On the 16V and G60's i have tackled the manifolding issue by creating my own system. Mindfull of the well known situation regarding tubular manifolds, i chose to improve upon the oe design front pipes. I now supply a larger bore stainless steel front pipe that incorporates a non restrictive flexible joint, and furthermore will fit into the stock system or any aftermarket system. To enhance the package i recommend porting and flowing the cast manifold. The front pipes are £250 and porting the manifold is £80. The early 16V Corrados, not having a cat, need a cat by-pass pipe to overcome the removal of their oe front pipe which incorporates a resonator box as standard fit.

[davidwort 0]

Do you know if removing the front downpipe with it's integral silencer/resonator and fitting a cat bypass would reduce low end torque on a 16v, don't some engines need a certain amount of back pressure to work most efficently?

Probably nothing to do with it but i remember my jetta lost most of it's power when the exhaust fell off! :D :shock: :D

 

David.

 

On the 16V and G60's i have tackled the manifolding issue by creating my own system. Mindfull of the well known situation regarding tubular manifolds, i chose to improve upon the oe design front pipes. I now supply a larger bore stainless steel front pipe that incorporates a non restrictive flexible joint, and furthermore will fit into the stock system or any aftermarket system. To enhance the package i recommend porting and flowing the cast manifold. The front pipes are £250 and porting the manifold is £80. The early 16V Corrados, not having a cat, need a cat by-pass pipe to overcome the removal of their oe front pipe which incorporates a resonator box as standard fit.

[Rpmayne 0]

My mate fitted a 4-1 magnex manifold and complete system to his 16v mkII golf and got 160bhp. (up from 139) Very noticeable improvement, 140mph on the clock. I also fitted a similar system to an 8v mkII golf with induction kit and got 130bhp (up from 112). These were dyno readings, not sure what the power actually was before but the driving was definitely more fun. :D Possibly lost abit of bottom end with those manifolds though.

[Bally 0]

My mate fitted a 4-1 magnex manifold and complete system to his 16v mkII golf and got 160bhp. (up from 139) Very noticeable improvement, 140mph on the clock. I also fitted a similar system to an 8v mkII golf with induction kit and got 130bhp (up from 112). These were dyno readings, not sure what the power actually was before but the driving was definitely more fun. :D Possibly lost abit of bottom end with those manifolds though.

 

what manifold was it? how much?

[Kevin Bacon 5]

Do you know if removing the front downpipe with it's integral silencer/resonator and fitting a cat bypass would reduce low end torque on a 16v, don't some engines need a certain amount of back pressure to work most efficently?

Probably nothing to do with it but i remember my jetta lost most of it's power when the exhaust fell off! :D :shock: :D

 

David.

 

Yeah you are right. I don't full understand the theory of inlet and exhaust pulse dynamics but yes engines do need a certain amount of back pressure to work properly. I think it's something to do with the spent gases travelling down the exhaust system, which creates a vortex/vacuum or something which aids cylinder filling when the inlet valve/s open.

 

Prolly completely wrong but it sounded impressive :lol:

 

Kev

[dubster82 0]

its not back pressure at all. thats a myth. thought exhausts are a calculation, and designed specifically. i dont know this personally, my mate knows all about it and its a lil confusing. he could go on for ages about it. hes a biker and it all couns for them :lol:

 

its actually a thing called scavenging which is needed to pull the gasses out of the cylinders etc..... and the bore determines the speed etc.... im not sure if this is 100% correct, but like i say, i lose track of what my mate says. thats why manifolds are shaped as they are. have a look at a 4-2-1 and wonder why they dont just link 1-2 and 3-4....

[16VG60 0]

Interesting as allways to read your views on this subject. Perhaps an easier way to tackle this situation is to accept that the manufacturer will typically produce a product which is a compromise between the ultimate state and economical viability. VW have rewarded us with cars over the years that leave the factory better appointed than most, but still we find room for improvement. Exhausts are typically designed to create acceptable performance characteristics and quiet operation. In my system i have identified a compromise in the manufacturers product, which creates a restriction in the exraction of exhaust gasses. To overcome this i have increased the bore sizes and match ported adjoining components, without removing any of the key factors like fit or flexibility. This system i have used with good effect on both 16V and G60 engines all with capacity increases, achieving significant power gains. In the same way tubular manifolds have shown to improve extraction of exhaust gasses so does this package but without the risk of stress fracturing.