Hi All,

I have a stock 998 with extractors and exhaust running a stock Hs2 and being new to working on cars in general (other than basic maintenance) I was wondering what I would need to look out for if I wanted to change to a Hs4 and do the work myself. Is it essentially a bolt on replacement given both carbs are in good running condition?

Is there anything I should be keeping in mind before I attempt the swap myself?

Thanks

The bolt pattern and the throat diameter of the manifolds are different between the HS2 and 4. You will need to change the manifold out for a carb swap, but other than that, it is not a difficult job. Needle selection will need to be looked at as well, but there is plenty of information and people you can see about choosing the right needle.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

Well, since you have extractors you probably have an aftermarket inlet manifold or a cut-down stock manifold. It seems a little strange to make that change without changing the carby over, since that's probably your biggest limitation at the moment. An aftermarket inlet would be the biggest job here.

Since you already have extractors, and if you're changing the manifold, you can probably get close to the right needle by asking around, but in the end you'll want to take it in to get it professionally tuned. That'll make a world of difference.

Well dont mind me but on closer inspection I already have a Hs4. Serves me right for listening to the previous owner rather than checking it myself properly.

The how to on identifying carbs helped..

Guess I will just change the filter over from the stock airbox and see how we go.

I was looking forward to giving this a go too..

It's a well known fact that the stock HS4 airbox with or without a K&N filter cartridge in it gives more HP & torque than a K&N cone sports filter does, once you drill some 20mm holes in the front of it..

I found the link...

All you K&N sports filter lovers, read this and weep-
http://www.minimania.com/web/SCatagory/ ... ticleV.cfm

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Thats a great article.

I have a ramflo with unifilter in the post but this could be worth a try as well