205 Mi16 4-2-1 Manifold

[Jonmurgie 2]

Well I confirmed this weekend that my 4-2-1 manifold has cracked:

 

 

And I have an 'in' with a stainless steel exhaust manufacturer and was considering looking at getting a small batch of them made up... but before that I wanted to find out who currently makes/supplies the 4-2-1 manifold for a 205 Mi16?

 

So, who does? So far I have:

 

1. Miles / Mild Steel / ~£350

 

Can anyone add to the list?

[smckeown 1]

maniflow manufacture the longman's one don't they

[Jonmurgie 2]

Yeah, they do:

 

1. Miles / Mild Steel / ~£350

2. Maniflow / Mild Steel / ~£380 (or are these stainless, hard to tell from their website)?

[Batfink 201]

no-one creates a stainless one to my knowledge, though Miles said he could it would be a lot of money

[Malachy 0]

why not reweld that ?

[Dj_mini 7]

Torque tecnique (cant spell) in wilton wiltshire makes the pug spares manifold out of mild or stainless steel but he said the mild steel ones are better as they dont hold the heat so much and dont crack as fast as stainless.

[DaveK 0]

why not just re-weld it mate? save a packet?

[Jonmurgie 2]

I will also look at welding it up (it's already been fixed once, and the crack is huge!) but I'm going to look at having them made in stainless as well

[C_W 3 1 Cars]

I wouldn't have thought stainless is the best choice for a manifold application? isn't it a bit too brittle?

[Wurzel 16]

Is the cracking due to heat or movement though?

 

Not too sure if you're using the heat tape, but I've heard this can accelerate cracking (which is why I never used it in the end).

 

Only saying this as you say it's not the first time you've had to repair it , plus I've got one fitted to mine and would like it to stay in one bit.

[smckeown 1]

are yopu running with a solid bottom ?

[Jonmurgie 2]

The first repair wasn't a crack, it's Sean's old manifold and it needed a fix where someone had tried to port-match it to a head, so as far as I know this is the first time it's cracked.

 

It was wrapped in heat wrap... and to be fair it does an AMAZING job of keeping the heat out of the engine, you can hold your hand over the manifold right after coming off track! But there are downsides, it speeds up the corosion of the metal so a stainless manifold wrapped would be much better.

 

I'm running a GrpN lower mount so don't feel it's cracked due to movement, more likely heat or something... it has been fine but seems to show signs of cracking not long after being mapped on the MoTeC...

 

Will see what the exhaust guys say...

[Malachy 0]

The first repair wasn't a crack, it's Sean's old manifold and it needed a fix where someone had tried to port-match it to a head, so as far as I know this is the first time it's cracked.

 

It was wrapped in heat wrap... and to be fair it does an AMAZING job of keeping the heat out of the engine, you can hold your hand over the manifold right after coming off track! But there are downsides, it speeds up the corosion of the metal so a stainless manifold wrapped would be much better.

 

I'm running a GrpN lower mount so don't feel it's cracked due to movement, more likely heat or something... it has been fine but seems to show signs of cracking not long after being mapped on the MoTeC...

 

Will see what the exhaust guys say...

looks like a poor weld in first place, has not penetrated and therefore cracked

[smckeown 1]

The first repair wasn't a crack, it's Sean's old manifold and it needed a fix where someone had tried to port-match it to a head, so as far as I know this is the first time it's cracked.

 

Yeah never suffered a crack or needed repair while I owned it. As you know PumaRacing had a go at matching, realise he was going to run out of material and stopped. BAsed on the receipts I had from the previous owner, I would say the manifold is 5 years old.

 

 

I'm running a GrpN lower mount

 

I'd still look at a solid mount, especially the abuse you give a car. You want to try and prolong the life of a manifold

Edited May 2, 2006 by smckeown

[Guest Armin205]

made in china?

[James_R 3]

simpsons could make you a nice one off one to suit the new engine (cam spec and all not a generic one [although I'm not complaining about them])

 

here's some pics of a mates car that's just been done:

 

http://www.migweb.co.uk/forums/vauxhall/ca...-erm-no-11.html

[smckeown 1]

Tony Law are another reputable company. Although their attitude stank when I talked with them last year

[Miles 331 1 Cars]

Mine are £325.00 posted all in,

But I might be looking at a sample of a 4-1 design to see what happens with the HP & Torque.

Mild steel is better for a manifold, More flexable and has different heat properties to Stainless Steel not that it's a bad thing on a road car.

[Henry Yorke 269 3 Cars]

Also mild steel has better sound resonance properties than stainless so if you do get a stainless manifold then you will get closer to the noise restriction limits.

 

Exhaust corrosion tends to occur with the exhaust heating up and cooling down where the water vapour in the air helps along this process too. Police cars rarely change their exhaust as they are in use all the time. suppose the same applies to Toyota Avensis minicabs too!!

[pug_ham 242 3 Cars]

I'm running a GrpN lower mount so don't feel it's cracked due to movement

I'd still look at a solid mount, especially the abuse you give a car. You want to try and prolong the life of a manifold

A groupN mount is pretty damn solid, there are no spaces around it to allow movement.

 

For all the difference a solid alloy one would give I'd stick with the group N mount.

 

Graham.

[Wurzel 16]

I guess the answer to remove as much restraint on the manifold as possible, is to use one of those short flexible joints (looks braided from the pics). I know there is a flexible spring clamp based idea but it still looks fairly solid and there will be a fair bit of leverage still on the manifold.

 

It looks like it would isolate it from vibration against the remaining, quite heavy, exhuast.