11 replies to this topic

[SAL 821X]

Morning chaps.

 

I rebuilt the HIF carb last night with a new yellow spring, needle and float chamber seal in a attempt to stop it pi**ing fuel every where!

 

Just wanted to check that I have blocked the right pipes up that I do not need?

 

I believe the fuel inlet is this one with the little bit of hose on and the one next to it with no hose is the breather?

 

 

 

Thanks in advance....

 

 

[SAL 821X]

Also another question come to think of it. 

 

Is the carb pictured above HIF38 or HIF44? 

 

I thought it was a 44 so I have bought a BDK needle and installed it. When I took the old needle out it was marked ADS which I believe is more suited to 38 carbs?

 

I'm now not so sure if this carb is a 44 or 38...

 

Will the BDK needle still be ok or will it be too rich.

[Swift_General]

That's an HIF 38. Your float breather is the upper left pipe so must be open to ambient pressure. I think (hopefully someone can confirm) that the lower right pipe was way of weakening the mixture at part throttle for economy and was connected to the pipe on the manifold flange that looks like it's blanked off. At part throttle cruise conditions the vacuum of the manifold would weaken the mixture.

Edited by Swift_General, 01 April 2016 - 10:03 AM.

[GraemeC]

44 or 38?  Simply measure the diameter of the opening at the manifold face - 44mm or 38mm.

[ukcooper]

Edited by ukcooper, 01 April 2016 - 12:09 PM.

[SAL 821X]

44 or 38?  Simply measure the diameter of the opening at the manifold face - 44mm or 38mm.

 

Sometimes even my own stupidity amazes me! 

[SAL 821X]

 

Bang on cheers... 

 

I searched hi and lo on google but couldnt find any images as clear as that.

[ukcooper]

Welcome :)

Some else pictures I just edited the a little lol.

Spread the word as they say.

[SAL 821X]

Definitely a 38 looking at the tell tale signs above. 

 

Now to see if the BDK or ADS needle is the best to run with. 

 

Engine spec's 1330cc, 37/31cc head, swift tune SW5 cam, uprated rockers. 

 

I found another post that suggested downloading WinSU from here http://www.winsu.co.uk/

 

Just downloaded and entered the spec as best I can and it's saying use ADY I think. Which would make sense as the graft shows ADY being between ADS and BDK. 

[SAL 821X]

He is the graph from the WinSU software showing BDK (green) ADY (blue) and ADS (red) based on engine spec and HIF38.

 

 

Doesn't make much sense to me but I'm guessing the BDK needle is thinner at peak power adding more fuel right?

[Scott@minispeed]

You need to use a needle starting with A NOT B. Your carb has a 0.090" jet, HIF44 has a 0.100" jet and uses needles starting with B

[SAL 821X]

Cheers Scott. 

 

I've put the ABS needle back in now.

 

Still cannot get it running though... hahaha