carb needle and spring

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minitravellerman
1275 Cooper S
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carb needle and spring

Post by minitravellerman »

I'm trying to fine tune my rally Mini following some upgrade work so wondering what carb needle and spring would be best for my spec. Maybe someone can help :)

The motor is a 998 A+ with 12G295 polished and ported head (unskimmed), and Minispares stage 1 kit. Carb is a single HS4.

Any idea what needle and spring spec would be best?
Ian Campbell
Spitz
998 Cooper
Posts: 585
Joined: Thu Jun 24, 2010 5:37 pm
Location: Saskatchewan, CA

Re: carb needle and spring

Post by Spitz »

If you've not skimmed the head your CR is going to be pretty darned low ....unless you're using D top pistons that is.

As for needle, I have a similar setup and I'm running an AAU needle ( but my 295 head is skimmed )

The combustion chamber of the 295 is a lot larger volume than a stock 998 head....that's the reason skimming is needed.
carbon
998 Cooper
Posts: 518
Joined: Fri Jan 07, 2011 8:26 pm
Location: Scotland

Re: carb needle and spring

Post by carbon »

Used to run an old 998 (dished pistons) with 295 head, but it had been well skimmed.

The best spring to start with for HS4 is red. Can't be much help with the needle as this was custom modified by Aldon when they set it up on the RR.
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