andyfreelandy

Well-Known Member

• Nov 27, 2020

• #1

Anyone fitted a 4-2-1 tubular exhaust Manifold to. 1.8k?

Does it deliver any benefits to performance?
Does it still need heatshield or is it better to ceramic dip it?

Just wondering as have been offered a stainless one.

 

Nodge68

Well-Known Member

• Nov 27, 2020

• #2

It depends on the year of the engine it's being fitted too? If it's an early 1.8 without the pre-cat, then it'll make so little difference, it's a pointless exercise.
On the later 1.8 with the pre-cat, then removing the cat and fitting the 4-2-1 will gain a couple of ftlb of torque, by virtue of better scavenging. However the cat and exhaust are also restrictive, so any gains are minimal, unless you're going to redesign the whole intake and exhaust system.

 

andyfreelandy

Well-Known Member

• Nov 28, 2020

• #3

Thanks John, system also available, will have a look and a think about it.

I hate the heat shield it is tatty and cracked, but essential I guess. Was thinking of ceramic coating the Manifold and binning the shield.

 

Nodge68

Well-Known Member

• Nov 28, 2020

• #4

andyfreelandy said:

I hate the heat shield it is tatty and cracked, but essential I guess. Was thinking of ceramic coating the Manifold and binning the shield.

Click to expand...

You can use thermal wrap on the manifold, which although not particularly attractive, will cut the thermal radiation in the engine bay.

 

htr

Well-Known Member

• Nov 28, 2020

• #5

Will that thermal wrap increase the temp' of the head?

 

kermit_rr

Very

Full Member

• Nov 28, 2020

• #6

I've read the thermal wrap can trap moisture, but i don't know if that is made up by people selling alternative solutions.
Either way it should be applied VERY tightly not just wound on

 

Nodge68

Well-Known Member

• Nov 28, 2020

• #7

htr said:

Will that thermal wrap increase the temp' of the head?

Click to expand...

No. The head is water cooled.

kermit_rr said:

I've read the thermal wrap can trap moisture, but i don't know if that is made up by people selling alternative solutions.

Click to expand...

I've not seen that on a stainless manifold, even after 10 years under the wrapping.

kermit_rr said:

Either way it should be applied VERY tightly not just wound on

Click to expand...

It does, and it needs securing with stainless cable ties or hose clips.