11 replies to this topic

[minituners]

i have just fitted a stage 1 kit (rc40) with minispeed inlet and i think the carb is an hif 40 but im not sure how can i tell ?
i have got it all up and running but the air/fuel mixer screw is turned all the way out and its fitted with a AAA needle
it has a flat spot when you change gear at low revs does any body know if a needle change would fix this or am i stuck with this also does any body in the cambridgeshire area have a carboniser or colourtune that they would concider lending or maybe giving me a hand with this

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[Retro_10s]

You need to book the car in for a Rolling road set-up (this is the ONLY way to get the car running correctly now you have buggered the fuelling about with the stg1 Kit.)

The problems you are getting are firstly due to the Carb being incredibly mal-adjusted, ( I 'think' the initial factory setting is created by twisting the screw in all the way and then out 2-3 full turns, can someone confirm this?) and secondly, I suspect, Not having the correct needle, was it supplied with the stage 1 kit?

A good rolling road set-up is needed, the operators will know what the car needs that it is not currently getting, and will be able to tune the car for optimum performance given the engine's condition and state of tune. Book it in as soon as possible.

It goes without saying that running an engine with the wrong fuelling can very quickly destroy your engine....

Oh and your carb can be identified as either an HIF38 or an HIF44,... the 38 and 44 bit are reffering to the width of the hole,... 38mm or 44mm, measure it and find out. Also the HIF bit stands for 'Internal float' you definatley have an HIF carb of some description.

Edited by Retro_10s, 22 December 2007 - 03:17 PM.

[Ethel]

Easiest way to get an SU's mixture back to a starting point to adjust from is to whip the dashpot 'n piston off and adjust it so the jet is flush with the bridge.

A flat spot could be down to ignition timing: you also effect an engine's ignition advance requirements when you improve its breathing - it should generally require a bit less advance. If you set up the mixture using the lift pin it's the idling mixture you are setting so any mismatch of the needle will be seen elsewhere in the rev range.

[minituners]

the AAA needle was in the carb when i brought it second hand with a load of other bits do you think that this carb is too big for my little 998 engine or is it not a problem? im not sure but i dont think there is a rolling road near me does any body know of a dyno near cambridge?

[Ethel]

the AAA needle was in the carb when i brought it second hand with a load of other bits do you think that this carb is too big for my little 998 engine or is it not a problem? im not sure but i dont think there is a rolling road near me does any body know of a dyno near cambridge?

A Hif 44 would be a bit big for a 998, a 38 would be better.

[minituners]

i started by getting the jet level with the bridge but it was trying to stall as i pulled off the only way i can get it running smooth ish is by unwinding mix screw out as far as it will go if not it just bogs down as i change from 3rd to 4th i have not touched the ignition since fitting kit as i had just replaced everything prior would it help do you think if i close the gap slightly between the contact breaker (points)

[Ethel]

No, the points gap has nothing to do with the timing (well it does, but it's no way to adjust the timing) set it as specified, preferably with a dwell meter.

Find out if the carb's a 44 or 38 for starters

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

& WinSU - a downloadable programme may be of interest to you.

[minituners]

i have mesured it at the back of the carb (intake) while on the car so not 100% accurate but i checked three times and im sure its 40mm wide

[minislapper]

If you put some decent pictures up, someone will be better able to identify what it is for you.

[Ethel]

Hif38 I'd guess, don't think a AAA would be standard fitment on a 44. Cut a strip of card to exactly 38mm it will be obvious if it's 6mm short if you hold it inside the carb's mouth. If it has an ID tag still on a dashpot screw someone will prolly know the number.

[Retro_10s]

To add to what Ethel just posted up,.... If there is an ID tag on the carb somewhere with a little code on that will be something like FZX141414 <-- or something like that,... Then go to the 'Burlen' website and punch in the code on their 'find out what carb i have' feature.

You'll also find out what year it was made and from what car it came from,... though most HIF38's seem to have graced a metro at somepoint

You'll be given a bloe up diagram labelling the parts of the carb etc,... this should include the standard type needle,... from there you could get a Needle that's one stage richer I guess,... but really... A Stage 1 kit would usually come with one!

[minituners]

its a 44 i have measured it accuratly now metro turbo i think can the main jet be swapped for that of a 38 or similar would this make a difference or is all the ajustment in the needle