Hi there
I have a std 1098cc motor all thats been done is
it has a set of extactors and a 1 1/2" su. I have put in a
red spring and BQ needle that vizard recommended in tuning the a-series
i took it to a dyno and it was really lean all through the rev range.
we had to file the needle right down to get the afr down to 15:1 at cruise. its still not right.
has this happen to anyone else?
what needle do u guys recommend, or do i go to a 1 3/4" su ?

thanks

Floating needle ADC Red spring

Fixed needle HG Red spring

I use a heated manifold and a K&N cone filter on my 1100 with 1 1/2 SU
( I currently use a No 7 fixed needle but will be changing to a HG as the No 7 is just a little rich from idle for my liking )

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see if you can work out how to use this...

http://www.morrismini.com/suneedlesv2.aspx

put BQ in where it says Needle Number at the top left, then put a tick in the box next to each station, and put in a figure under richer or leaner, then click lookup. So if you want a needle that's .020" richer across the whole range, tick all of the boxes and put in .020" in the richer column and you'll get a list on the right hand side. Click Show Chart and you'll get them as a chart. You can make a short list by adding needles to the short list, and display just those. Whereever you click 'Lookup', it'll show on the left hand side and you can filter it.

Hi norm74,

Those guides in Vizards books are just that,,, guides he even says so in the same chapter.. so I wouldn't be worried if it wasn't right... It doesn't take into account fuel octane and more importantly, it doesn't cover every single posible combination of parts and set ups.

Using Simon K's link you should be able to work out what you need if you know where it's lean... otherwise a good dyno tuner should be able to recomend you a needle

Good luck with it and all the best

I would use a no.7. they seem to work well.

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Try a no.4 it worked in ours.

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That's why it's good to be.............ME

here you go - all 4 mentioned side-by-side http://www.morrismini.com/SUNeedlesV2.a ... 4;7;BQ;HG;

That damn interesting Simon, the No 7 I,ve got now is as I thought a bit richer at idle, on the other chart I use the HG has a nice curve with a bit more up top but your chart shows a big difference between the No 7 and the HG, it seems the No 7 runs out of puff after Station 9, it would be a big difference switching to the HG.
On my standard 1100 ( no rebore ) I run a 12G295 has 26.9cc chambers with RimFlow valves, 1 1/2 SU on a Howley heated manifold, Perry 3-1 extractors and 1 3/4 exhaust, it could be that I,m flowing enough air that with the No 7 needle profile I,m possibly running lean at highway speeds.
Switching to the HG should fix that thats for sure !

Thanks Simon !


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I found the BQ a little on the rich side - down around 13 for most of the range. Probably OK for performance but not economy.
Put the E3 in and it looks good - AFR around 14 to 14.5 for most of the range. Good for economy.
This is on an 1160cc, stock cam, stock head, basic extractors and 1.5 inch SU on cut down manifold.