20v Header

[SuperRedMR2]

I have sourced a 20v 4age header, can anyone tell me if I have to modify my exhaust downpipe to suit this?

I know I have to match the 16v holes on the header up top that's not a problem.

Any ideas?

Cheers

[kaiowas]

I'm pretty sure the flange between manifold (we're not in America ) and downpipe is different on a 20v. I'd be surprised if it was in exactly the same place as well so there may be a little bit of cut and shut required.

[SuperRedMR2]

Balls! That's a shame as it's a good price!

I do have spare exhaust at home, so I suppose I could fit that while my Janspeed is altered

[bwrc]

Have a look at sv3power.com they have a 20v manifold and down pipe available on exchange, modified to fit a 16v engine

[SuperRedMR2]

I've seen that site before but they are in the USA and it'd cost a hell of a lot more to get it done by them.

I can get my downpipe extended at work.

Thanks for the link anyway.

[gon]

I have made this mod on my one (I have a 20V header with a 16V exhaust).
If you bough the downpipe flange of the 20V its an easy fix .

What I have done was to cut the downpipe flange of the 20V and add about a 2 inch of pipe ....
Then cut the flange of the 16V and just joint the pipes together.
This happens on the merge from 4 to 2 pipes....

I have a picture somewhere



So in the picture you have the original 20V flange, a bit of pipe from the old 20v exhaust and the full 16v exhaust .....



Make sure you look and clean the inside ...

[SuperRedMR2]

Any noticeable difference?

[gon]

I also changed the engine to a blacktop 20v ....
so yes, there is a lot of difference but I suspect its not only the exhaust

[Lauren]

Is there really anything to gain here though, from fitting that manifold considering you'd need to do a fair bit of work?

[SuperRedMR2]

Chaps at work would do it for a tenner, but I still have suspension issues so prob won't do this now.

[pk_090]

I remember reading that kev.in tried this with his but found other problems, cant remember what exactly. Might be worth doing a search.

[SuperRedMR2]

Thanks Alex.

I think its the extension at the bottom flange for the downpipe which is required to not only obviously bolt the mk1 exhaust onto, but also needed to clear the starter.

I've sent him a pm

[pk_090]

If i remember rightly he was using a later non-tvis engine and it posed problems. Cant remember all the detail though.

[kevin..in]

If i remember rightly he was using a later non-tvis engine and it posed problems. Cant remember all the detail though.

no non tvis engine car went several years ago, 20v manifold I have doesn't fit due to clearance issues over starter motor and different flange (oooo flange!) it was on my to do list that is pending on another maybe I will list, beer token exchange and I could pass on my project

[elbon50]

Perhaps the starter could be moved out of the way at the back, on a car with a C52 box

[kevin..in]

Perhaps the starter could be moved out of the way at the back, on a car with a C52 box

was an option but too much work for as Lauren says not much gain other than maybe sound

[elbon50]

The stock 16v manifold is quite free flowing

[kevin..in]

The stock 16v manifold is quite free flowing

it is but it is also very heavy and can suffer from cracking (I am also aware that some aftermarket tube manifolds can fall to pieces infront of your eyes!

[kevin..in]

my one