6 replies to this topic

[beardylondon]

My Mk1 is running nicely, except there’s an exhaust leak, I suspect from the manifold again. About 10 years ago my original Maniflow LCB developed a crack, and I had to replace it. Hopefully that hasn’t happened again.

The current exhaust is a stainless steel single box Playmini item, I put on the vehicle 25 years ago and I have covered around 10,000 miles with it. It is still in surprisingly good nick. I presume the baffles on a 25 year old exhaust won’t be great, even after 10k. It does seem loud!

Im obviously older now and more interested in driving a quieter vehicle these days and have recently been driving a Mini with a quieter twin box RC40, so it got me thinking of putting something similar on the my Mk1, maybe maniflow variety.

The big BUT is, it is nicely tuned and Im wondering if a twin box will restrict the current set up, as I don’t particularly want to go to the expense/hassle of getting it tuned again.

Obviously there’s a cost attached to swapping to a twin box, and maybe it’s just easier to fix the current leak and leave it be.

It’s 1293 with Newman 270 cam, 1.75” HIF44.

Thoughts?

[lippo]

 I swapped a stainless steel single box exhaust for a Maniflow twin box. I have a Maniflow LCB too. More than happy with it and it isn't too loud. My 1275 is standard but I can't see your engine being limited by the twin box at all.

Edited by lippo, 09 April 2025 - 06:21 PM.

[Cooperman]

I run twin-box RC40 system on both my rally cars and they are quiet enough to pass noise scrutineering. 

You shouldn't to do anything to the mixture or timing to switch the that or the Maniflow twin-box system.

A good system is an RC40 rear box with a Maniflow 'cherry-bomb' forward silencer box and I have used this in the past.

[andyapanel]

While I echo everything folk have said about Maniflow kit, their back office is a bit iffy in my experience; I have been trying to get a reply to a query about the replacement hanger set I bought from them several months ago.
The exhaust system I have is excellent.

[coopertaz]

if you already have an lcb manifold changing the exhaust back from this will not affect the running. remeber budget manifolds used to split at the y section never had problem with maniflow ones unless the lower clamp on the gearbox comes adfrift

[beardylondon]

It was a Maniflow LCB which split, all the mounts were fine.

[beardylondon]

Thank you.

The RC40 rear box and Maniflow sounds good, please could you link to the exact Maniflow product you are referring to?

I run twin-box RC40 system on both my rally cars and they are quiet enough to pass noise scrutineering.
You shouldn't to do anything to the mixture or timing to switch the that or the Maniflow twin-box system.
A good system is an RC40 rear box with a Maniflow 'cherry-bomb' forward silencer box and I have used this in the past.