ausmini
https://ausmini.com/forums/

SU Needle recommendations please
https://ausmini.com/forums/viewtopic.php?f=5&t=80176		 Page 1 of 1
Author:  phillb [ Sat Feb 02, 2013 11:33 am ]
Post subject:  SU Needle recommendations please
My car currently runs twin 1.5 SU's

However, I'm about to fit an original standard set of Cooper S 1.25 SU's. I'm after suggestions as to which needles may best suit based on others experience with a similar setup.

1275 bored out 0.060 to 1330
Standard Cooper S Cam (as far as I know)
1.5 rockers
LCB extractors

Cheers

Phill
Author:  lisian_1275 [ Sat Feb 02, 2013 1:35 pm ]
Post subject:  Su Needles
Hi Phil
Would run M needles and Red springs.
Why the change from 1.5" SU's?

Thanks

Ian
Author:  phillb [ Sat Feb 02, 2013 7:03 pm ]
Post subject:  Re: Su Needles
lisian_1275 wrote:
Hi Phil
Would run M needles and Red springs.
Why the change from 1.5" SU's?

Thanks

Ian


Hi Ian,

Just would like to eventually return the car to original, or at least collect all the original bits (I now have the original steel "s" rims on the car ...if you remember I got them from you)

I'll keep the 1.5's, but they need servicing badly.

A couple of people have said with the 1.25's I may even find they give a little more pull low down and I'll just lose a little in the mid and top end.

Will be interesting to see the difference.

Cheers
Author:  simon k [ Fri Feb 15, 2013 5:27 pm ]
Post subject: 
M needles were original fitment, I played around with them a lot a while ago and M's were too lean even on a standard motor... todays fuels are different to what was available when they were new.

AH2's were OK I think, but maybe ended up too rich - Dad's car has AH2s

you just need a starting point - bung in what you've got, set it up as best you can then see what the mixtures are like
Author:  BALLISTIC [ Fri Feb 15, 2013 10:10 pm ]
Post subject: 
Id start with M needles, but I think you may need needles a touch richer such as AH2 or H4 . . .

http://www.mintylamb.co.uk/suneedle/

Heres a link for a good place to compare . . .
Author:  phillb [ Sat Feb 16, 2013 12:32 pm ]
Post subject: 
Thanks guys, I have some M's so I'll give them a go, I also have some AH2's to try. I have 6's in the 1.5 SU's but I suspect they are too rich at the upper end, you can see fumes with hard acceleration at highway speed.

I was wondering with the physics of it all does the slightly greater capacity from the rebore make that much of a differece to the needle selection.

I guess a rolling dyno is the only way to be sure.
Author:  drmini in aust [ Sat Feb 16, 2013 1:43 pm ]
Post subject: 
phillb wrote:
Thanks guys, I have some M's so I'll give them a go, I also have some AH2's to try. I have 6's in the 1.5 SU's but I suspect they are too rich at the upper end, you can see fumes with hard acceleration at highway speed.

I was wondering with the physics of it all does the slightly greater capacity from the rebore make that much of a differece to the needle selection.

I guess a rolling dyno is the only way to be sure.

Hi Phill,
You can also attach a portable A/F ratio meter with a probe in the tailpipe and go for a drive... it's what I do with my Dellorto.
Only takes 5 mins to set it up,
PM me if you want to come up and try it... :wink:
Author:  phillb [ Sat Feb 16, 2013 7:44 pm ]
Post subject: 
drmini in aust wrote:
phillb wrote:
Thanks guys, I have some M's so I'll give them a go, I also have some AH2's to try. I have 6's in the 1.5 SU's but I suspect they are too rich at the upper end, you can see fumes with hard acceleration at highway speed.

I was wondering with the physics of it all does the slightly greater capacity from the rebore make that much of a differece to the needle selection.

I guess a rolling dyno is the only way to be sure.

Hi Phill,
You can also attach a portable A/F ratio meter with a probe in the tailpipe and go for a drive... it's what I do with my Dellorto.
Only takes 5 mins to set it up,
PM me if you want to come up and try it... :wink:


Thanks Kev, that would be awesome. I'll PM when I'm ready. The 1.25s are still sitting on the workbench waiting to be fitted.

Would be interesting to see what the 1.5's are doing before i remove them too. I'll be in touch, much appreciated.

Phill
Page 1 of 1 All times are UTC + 10 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/