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Posted: Sun Apr 26, 2009 9:20 pm
by Matt
Best bet is to get an aftermarket exhaust with an LCB either from one of the minor suppliers or from Maniflow direct (maniflow ones are very good quality)

There will be an improvement from doing this, but having a good head will increase the improvement dramatically. You really want a 12g295 which has been skimmed. I happen to have one that I want to sell, skimmed and ready to bolt on. Standard fitment on 998 mini coopers and 1098 midgets but nothing else.

Posted: Sun Apr 26, 2009 10:33 pm
by bmcecosse
And MG 1100.

Posted: Sun Apr 26, 2009 10:48 pm
by Matt
Ahh yes, sorry - but they are not that common

Posted: Sun Apr 26, 2009 10:50 pm
by bmcecosse
Were very popular in their day! Certainly not 'common' - very upmarket!

Tuning

Posted: Mon Apr 27, 2009 7:32 am
by Declan_Burns
Has there been a change of heart? I thought the 12g940 head was supposed to be the best mod. I haven't fitted mine yet and I will wait until it has it's TÜV (our MOT every two years FYI) in May. What's the advantage of the 12g295?

Posted: Mon Apr 27, 2009 7:52 am
by bmcecosse
Not at all - the 940 head is by far the better bet - but this lad was simply wanting to improve the breathing by fitting twin carbs - the discussion has moved on from there, and as he appears to be a relaitive 'beginner' the simplest move is to use the easy 'bolt on' option of the 295 head, which does give an improvement. The 940 head needs a clear understanding of exactly what's going on - and is not a straight 'bolt on' conversion, without some meaurements/adjustments and precautions being taken - and I would therefore only suggest it to more experienced owners who are well versed in the operation of the A series engine !

Tuning

Posted: Mon Apr 27, 2009 9:08 am
by Declan_Burns
Thanks Roy,
I had thought I had gone down the wrong road! As a matter of interest, we had lovely weather here yesterday, so I tested the chopped off outlet manifold and the alloy inlet manifold yesterday. Although still with the original head and HS2 carb via a home made adapter. Even that made an improvement-especially at the top end. The acceleration seems a lot better. Is is however backfiring or popping now and again on the overrun and the plugs were white showing it is too lean. I've started setting it richer bit by bit and am finding the plug colour changing slightly towards the desired tan. Still popping and spitting now and again. I'll try the HIF 38 too as soon as the weather picks up. Just doing this as a learning process.

Posted: Mon Apr 27, 2009 4:08 pm
by d_harris
bmcecosse wrote: and I would therefore only suggest it to more experienced owners who are well versed in the operation of the A series engine !
Not true, you suggested it to me when I got my 295! :P

Its amazing how much of a difference a decent inlet, carb and filter makes though, even without swapping the head (my engine is still stock, take for those two...) but the 295 will go on soon

Posted: Mon Apr 27, 2009 11:18 pm
by bmcecosse
Obviously - I considered you to be 'well versed' Dan ! It was hardly your first post I suspect!!
The inlet helps performance by eliminating the 'hot spot' - to get the running mix correct you probably need a different profile needle - but if changing to HIF38 shortly I'm sure you can live with a slightly erratic idle for a wee while.