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Rich Needles - AUD1474 - Guidelines for use?

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SteveHall64Healey

Jedi Trainee
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Does anyone know of any guidelines for the use of rich needles (AUD1474) versus the standard needles on the HD8 carburetors? I am wondering when to use the rush needles instead of the standard needles.

Thanks
Steve
 
I think they'd only be required in non-stock engines; i.e one with headers, higher compression or intake/carburettor mods. I've run STD needles in my BJ8 for over 140K miles with no issues (and up to 25MPG in the right circumstances). This with mostly 10% ethanol gas, but some think the richer needles work better with 'gasahol.' I think you'd need a dyno session to determine if they offer your car any advantage.
 
It was recommended by a shop won't name to install the richer needles due to ethanol. I have found no change except a noticeable drop in fuel consumption. I will put the originals back next time I fiddle with the carbs.
 
I ran the rich needles all last year - about 1500 miles. Although my experience is not the same as a dyno session, my perception is that there was a bit more power, particularly in the upper rev range. Mileage was definitely worse and the plugs were quite obviously affected with carbon build-up. This year, I went back to standard needles and after 150 miles the plugs are a textbook greyish-tan colour with no buildup. The engine was rebuilt two years ago with a DWR8 cam from Dennis Welch and I thought it could tolerate more fuel.
 
I have a DWR8 cam and HD8 SU's and use the standard needles. The plugs are textbook color. I tried the richer needles because of the addition of 10% ethanol on the advice of a shop owner and didn't notice any improvement.
 
I have a 184 cu in, DWR 8 engine with HD8 DMD manifold, 1.6 rockers, forged pistons and Kirk headers - running dual O2 meters.

I ran the rich needles for a while and they showed better power at higher rpms, however it wasn't really noticeable and mileage was lower. Plugs were always pretty dark but no fouling on a newish engine.
 
tahoe healey said:
It was recommended by a shop won't name to install the richer needles due to ethanol. I have found no change except a noticeable drop in fuel consumption. I will put the originals back next time I fiddle with the carbs.
Click to expand...

TH - The needle recommendation's something of a surprise given the altitude you live at.
 
The shop knew where I live as he comes up here a lot. That was my question but he insisted it would help. As I have stated, I notice no change. It has always run well up here and if I am going to be down at sea level for any length of time I tweak the jets 1/8 of a turn.
 
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