13 replies to this topic

[driftz]

Quick question. I have just picked up a 75 mini with an MG Metro 1275 A+ engine. It is running an HS4 carb that I have cleaned and tuned but it is a bit down on power. I will be putting on an LCB header, exhaust and intake manifold shortly but will be keeping the carb until I can save up for an HIF44.

 

In the mean time, I am wondering if anyone here has any experience/advice on a good setup for needle and spring to run in the HS4 to make the most of the current setup.

 

cheers

[Spider]

If the engine is fairly standard you could start with an ABB or AEM Needle and a Red Spring.

[driftz]

Thanks! Yes, becides the mods listed, the only other thing I will be possibly putting on between now and when i get a 1.75" carb, is electronic ignition.

 

I was figuring a yellow spring because the red spring is used for mild 998 using hs4, am I wrong in thinking the red will still not be strong enough?

[Spider]

The above are only suggested safe starting places, I'd would still suggest kicking off with a Red Spring.

 

When you go over to a HIF44, the needle there to start with is a BDL and again a Red Spring, however these are a different spring for these to the HS4.

[carbon]

All standard 1275 motors fitted with the single HS4 carb used red springs, as Moke Spider says this is the best starting point.

Edited by carbon, 22 March 2015 - 08:59 PM.

[KernowCooper]

Not sure your spec is going to give any worth while gains changing to a Hif44,and the BDL is a standard needle for a MG Metro and your engine is not at that spec the BDL could turn out to be to rich.

[driftz]

perfect i will try a red spring. I have got a few suggestions to use an AAA, AAU, AAM, ABB and AEM. That is still quite a bit varied. Trying to avoid buying a whole load of needles.

[carbon]

Needle selection as starting point will depend heavily on inlet and exhaust.

 

If you are using a good K&N type air filter, LCB and RC40 then something like AAA would be decent starting point.

 

If using standard air filter and exhaust then ABB or AAT would be more suitable.

 

Whatever you start with it will likely take a rolling road session to get it correct.

[driftz]

Thank you, yes the engine will have a cone filter, intake manifold, lcb, and sportex single muffler exhaust. Becides the Pertronix electronic ignition, the engine is stock MG metro 1275 A+.

 

Looks like im going to start with a red spring and a AAA needle. If anyone has any other suggestions with similar setups please feel free to chime in

[driftz]

sorry to bring up a dead thread but after review these answers iv realized all the recomendations are for spring type needles and my hs4 is a fixed type, unless i can just pry off the little spring hat and use a AAA in my hs4?

 

otherwise what would be be fixed needle equivilant to a AAA? cheers

[Scott@minispeed]

Yes you can press the needle out of the spring hat and use it, red spring with AAA is what we would suggest too

[carbon]

sorry to bring up a dead thread but after review these answers iv realized all the recomendations are for spring type needles and my hs4 is a fixed type, unless i can just pry off the little spring hat and use a AAA in my hs4?

 

otherwise what would be be fixed needle equivilant to a AAA? cheers

Fixed needle No.7 is very close to AAA profile.

[David128]

Hi A good source of info is mintylamb

 

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

[David128]

And winsu

 

http://www.winsu.co.uk/