A Needle Question
Created by: metalwright
Orig. Posting Date | User Name | Edit Date |
Aug 28, 2017 04:26PM | metalwright | |
Aug 18, 2017 12:24PM | malsal | |
Aug 18, 2017 11:57AM | metalwright | |
Aug 18, 2017 08:17AM | Spitz | |
Aug 17, 2017 06:18AM | Alex | |
Aug 17, 2017 05:49AM | metalwright | |
Aug 17, 2017 05:31AM | mur | |
Aug 17, 2017 05:03AM | metalwright | |
Aug 17, 2017 04:44AM | Dan Moffet | |
Aug 16, 2017 07:20PM | metalwright | |
Aug 16, 2017 06:02PM | specialist | Edited: Aug 17, 2017 02:16AM |
Aug 16, 2017 05:25PM | metalwright |
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AAU seems to have done the trick. It runs a nice fat 13.5-14, only leaning a little on acceleration, and even then not too lean.
And on top of that, the mods really opened up this 1098, especially up above 3000rpm.. Really nice!
Anyway, thank you everyone for the helpful comments.
And on top of that, the mods really opened up this 1098, especially up above 3000rpm.. Really nice!
Anyway, thank you everyone for the helpful comments.
--trying to set a record for the longest Mini restoration ever!
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You just put your needle in the chart and look for one that is richer towards cruising speed. AAU as suggested is a good starting place.
If in doubt, flat out. Colin Mc Rae MBE 1968-2007.
Give a car more power and it goes faster on the straights,
make a car lighter and it's faster everywhere. Colin Chapman.
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Many thanks, gentlemen. I tried to use the minty need comparison, but didn't have any idea where to start!
I have an AAU on order... We'll see how it goes!
I have an AAU on order... We'll see how it goes!
--trying to set a record for the longest Mini restoration ever!
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I've not looked at the link yet, but for your set-up I would suggest an AAU
I'm running this on an 1130 and it works perfectly
An AAM was originally suggested for me a few years ago... but turned out to be far too rich
AAU
mintylamb has a great needle comparison chart. It does not make suggestions for application ( free version ). But is a great chart
I'm running this on an 1130 and it works perfectly
An AAM was originally suggested for me a few years ago... but turned out to be far too rich
AAU
mintylamb has a great needle comparison chart. It does not make suggestions for application ( free version ). But is a great chart
"Everybody should own a MINI at some point, or you are incomplete as a human being" - James May
"WET COOPER", Partsguy1 (Terry Snell of Penticton BC ) - Could you send the money for the unpaid parts and court fees.
Ordered so by a Judge
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The AAU is close, but does seem to lean out at the top end - I'm running one in my std 998 with big exhaust and proper inlet.
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Oh wow, that is almost my exact setup, except I didn't plumb the coolant to the manifold!
" AAU - 1100cc, 1.5in SU, 3into1, heated inlet, RC40, K&N"
Thank you, sir!
--trying to set a record for the longest Mini restoration ever!
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No need to apologize, your original post made sense to me.
Sometimes people don't answer when they don't have really specific experience with a combination; that is most of the board. At the same time, sometimes people write nonsense and then edit it to nonsense light.
Using one of the SU Carb needle generators on the Internet, I compared your present needle with a couple listed on this site for similar engines. The needle you have is leaner and would likely supply fuel as you have described.
Here is the page:
//www.minimania.com/Needle_codes_for_SU_carbs
I would think the needle they recommend for a 1098 with nearly the same mods would be a great start.
Sometimes people don't answer when they don't have really specific experience with a combination; that is most of the board. At the same time, sometimes people write nonsense and then edit it to nonsense light.
Using one of the SU Carb needle generators on the Internet, I compared your present needle with a couple listed on this site for similar engines. The needle you have is leaner and would likely supply fuel as you have described.
Here is the page:
//www.minimania.com/Needle_codes_for_SU_carbs
I would think the needle they recommend for a 1098 with nearly the same mods would be a great start.
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Yep, I see that my OP was very unclear. Apologies!
Wideband is happy with the fat mixture at idle. The sensor also confirms that somewhere around 3000-3500 the mixture jumps above 15.0, and then rises to near 16 as it continues to accelerate. It is nice to see the reading, as it confirms the engine feel of stuttering and what not.
Also, I've got 20w50 in the dash pot.
Wideband is happy with the fat mixture at idle. The sensor also confirms that somewhere around 3000-3500 the mixture jumps above 15.0, and then rises to near 16 as it continues to accelerate. It is nice to see the reading, as it confirms the engine feel of stuttering and what not.
Also, I've got 20w50 in the dash pot.
--trying to set a record for the longest Mini restoration ever!
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If you are happy with the sensor readings (throughout the rpm range under load?), that should be indication that the needle you have is good. If you have the slight hesitation, try different weights of oil in the dashpot damper. A lighter oil would allow the dashpot to rise sooner, giving LESS of the accelerator pump action, and a heavier weight would do the opposite. When the dashpot rise is slower, and the throttle plate opens, the engine vacuum pulls more fuel out of the jet, richening the mixture during the brief transition period - a spurt of gas. You need to determine if you need more or less of this effect. Try accelerating the warmed up engine with a bit of choke to see if it is better or worse. It might give an indication.
.
"Hang on a minute lads....I've got a great idea."
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This forum would benefit from a "block" feature. I'm not a programmer, though, so....
--trying to set a record for the longest Mini restoration ever!
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Check the dashpot oil level.
Happened to me,I checked the level and was way too low,topped it off and performance improved, hope this helps.
Happened to me,I checked the level and was way too low,topped it off and performance improved, hope this helps.
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Alright, I've got the mixture adjusted at idle, I believe. When I lift the piston it stumbles *just a little* initially, but not every time. Wideband O2 sensor seems happy enough with the fat mixture.
Runs good and solid through the middle of the RPM range. As I approach cruising speeds, it leans out significantly.
I have a HS4 carb. New alloy manifold and LCB exhaust are recent changes. 1098 engine.
Current needle reads ADF. Do I need a new needle for this new configuration?
Runs good and solid through the middle of the RPM range. As I approach cruising speeds, it leans out significantly.
I have a HS4 carb. New alloy manifold and LCB exhaust are recent changes. 1098 engine.
Current needle reads ADF. Do I need a new needle for this new configuration?
--trying to set a record for the longest Mini restoration ever!