21 replies to this topic

[roblightbody]

Hi there,

 

I can't find anywhere that can rolling road setup my engine properly (like I was told to do after it was rebuilt), therefore I'd like to have a stab at changing the needle I think...  I believe its on the standard needle just now.

 

Its a 1990 Cooper, engine was rebuilt to 1293, with this cylinder head, and a full Maniflow LCB exhaust without cat, and the usual K&N element filter.  To me it feels like its not giving 100% at full throttle, even though its quick, and on a light steady throttle - e.g. 35mph in 4th, or on overrun - it sort of hiccups.  Also it only just scrapes through the MOT because its rich at idle.

 

Suggestions and advice very welcome, thanks.

 

- Rob

[ukcooper]

well, my guess is a problem with the carb or another gasket its running rich ya be washing ya boars out if a decent r/r/ session cannot sort it then, time to look at your setup exhaust k*n etc.
what cams in it

[roblightbody]

Its a Cooper Mainstream - the one that was basically the MG Metro engine, but with the mods I mentioned.   Mini Sport's rolling road might be an option... its just that its 220 miles away, and says its only Monday to Friday too...

[carbon]

Central Scotland lacks any strongly recommended rolling roads. Ricky Gauld in Huntly gets good reports but he's the best part of 180 miles from Glasgow.

 

Sounds like your current needle profile may be running lean. Have you taken it out to see what needle you currently have fitted?

 

Also have you checked for any signs of wear on the needle - can you feel a ridge on one side of the needle about 3-4mm from bottom edge of the piston?

 

If there is any sign of wear you must also change the main jet before going any further.

[nicklouse]

so what is the needle that is in there now.

 

we need to know that first. so pop the top of the carb off and get the needle out and see what it says.

[Dusky]

Like nick says, depends on your needle atm.
Also, might be worth checking the ignition and fuel delivery. I've had weak fuel pumps wich caused lean running in the past.

[roblightbody]

Thank you!  I'm going to seek assistance from a friend to help with that, will let you know when I've looked.

[Agus1601]

I had same specs with my old hif 44 carb and use a needle leaner than the stage 1 kit offered.This should be the needle for you.

 

http://minispares.co...|Back to search

[racingbob]

got bce in mine with highly nmodded head mg metro cam done on dyno

[whistler]

If it's an RSP engine then it will have an MG Metro cam and the often used needle is the BDL which can be thinned when the car is rolling roaded.

[roblightbody]

Hi,

 

I've plucked up the courage and had a look (never done anything to the carb except check the oil, I'm much better with computers!) - its a BDK

 

When putting the needle back in, there's a black plastic bit at the base of it with the spring, I just pushed it gently home until it was flush with the metal, and then tightened the screw - hope that was right, seems OK now.

 

Thanks for all comments, reading them all.

 

- R

Edited by roblightbody, 01 April 2018 - 03:35 PM.

[bikewiz]

I have a similar spec 1293, I run a BBW needle and LZX2085 damper for what it's worth. We don't have easy access to dynos/rolling roads over here that would fit a mini, so I've tuned it really by running up and down the highway and doing plug checks. Could mine run better? I'm sure it could but the plug color and "seat of the pants" feeling on my car is good.

[hhhh]

[roblightbody]

Thanks.   I'm not quite sure what that chart is showing, but my needle - the BDK - appears the most "extreme" ?

[racingbob]

bdk will be to rich i reckon was in mine