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Needle for an HIF38 on a 1098?

Posted: Mon Jun 28, 2010 10:22 pm
by linearaudio
Has someone got the needle profile best suited to an HIF38 on an otherwise standard 1098??

Re: Needle for an HIF38 on a 1098?

Posted: Mon Jun 28, 2010 10:27 pm
by cadetchris
apparently accoring to billlobban, a needle with the number AAA is quite good, this knowledge was also gained from a well known Scotsman who roams these corridors

Re: Needle for an HIF38 on a 1098?

Posted: Mon Jun 28, 2010 10:43 pm
by billlobban
My 1098 has been modified somewhat but I'm also confused by your post about attaching both the carnkcase vent pipe and the servo th the carb
You might want to try this site http://www.mintylamb.co.uk/suneedle/

Re: Needle for an HIF38 on a 1098?

Posted: Mon Jun 28, 2010 10:51 pm
by cadetchris
ahh, i just bought a t piece from halfords http://www.halfords.com/webapp/wcs/stor ... yId_165562 and connected the vent and servo up, twice the suction with only one pipe

Re: Needle for an HIF38 on a 1098?

Posted: Mon Jun 28, 2010 10:57 pm
by linearaudio
I have an AAA in my 940 headed/ MG Metro cammed 1098, but this is way too rich for the Boy's standard 1098 ( he's just discovered how much it costs to run a car :D ).

Re: Needle for an HIF38 on a 1098?

Posted: Mon Jun 28, 2010 11:00 pm
by linearaudio
cadetchris wrote:ahh, i just bought a t piece from halfords http://www.halfords.com/webapp/wcs/stor ... yId_165562 and connected the vent and servo up, twice the suction with only one pipe
????? Don't think it's recommended practise to connect the engine breather to the servo, the vacuum produced by the inlet manifold is sufficient for the servo, and tee-ing it to the engine breather can only compromise that as the engine breather pulses in and out!

Re: Needle for an HIF38 on a 1098?

Posted: Tue Jun 29, 2010 9:48 am
by bmcecosse
The 'servo' will never work - if it's connected to the engine crankcase in ANY way! Madness. I don't know the needle for a standard 1098 with HIF38. I'll try to find out. Is the AAA definitely running too rich ?

Re: Needle for an HIF38 on a 1098?

Posted: Tue Jun 29, 2010 11:51 am
by billlobban
I cannot possibly see how connecting the servo to the crankcase ventillation system will work. What you will end up with is no servo. In any case why bother you've already tapped the inlet manifold for the servo connection - just use that.

With regards to the AAA needle my 1098 has a modified '295 head (9.75 to 1) and an MG Metro cam and for this set up works perfectly if a little lean on idle.

Re: Needle for an HIF38 on a 1098?

Posted: Tue Jun 29, 2010 4:33 pm
by linearaudio
bmcecosse wrote:.............. Is the AAA definitely running too rich ?
Yep, drinking the stuff. I have cobbled a three box straight-through 1 1/2" system onto his car which makes it VERY quiet, but doesn't appear to be causing excessive back pressure as she pulls happily through the range, just mention that in case there is any way that the exhaust could be the cause, any thoughts? I tried at first with just two boxes (ex VW Golf mk2), but she was a tad raspy). She has the ubiquitous MG Metro inlet manifold, and of course the famous LA "controlled vortex etc etc" headers coming off the BL cast LCB, otherwise all stock (at the moment :wink: )

Re: Needle for an HIF38 on a 1098?

Posted: Tue Jun 29, 2010 5:22 pm
by Stig
I'm running something very similar: MG Metro manifold with HIF38, larger exhaust on a 1098 (std. apart from 1.5:1 rockers)

I can't remember what needle I'm using but it's straight off a 1.0L Metro and I get over 45mpg on a long run.

There's not an inlet leak you're compensating for to get a good idle mixture is there? Just a thought, but I expect you'd notice the rough running.

Re: Needle for an HIF38 on a 1098?

Posted: Tue Jun 29, 2010 5:35 pm
by bmcecosse
According to my Metro manual - the 998 used an ADP needle in most models - ADS in the HLE version. Although the 1098 engine is considerably modified compared to a 998 (bigger inlets/better flowed head/better camshaft and obviously 10% more capacity) that needle could well be a good starting point. Certainly - 45 mpg sounds good!