2 replies to this topic

[Matteyboy1]

Hi all, 

 

I've got an issue with tuning my rebuilt 998 and brand new HS4 carb. 

 

I've spent hours in the garage getting the engine up to temp, trying to get the mixture spot on. I now have a problem where on idle its very smoky and when you begin revving, it creates these loud pops around the 2000/25000rpm area. 

 

It's got brand new plugs, leads, oil & filter, air filter, fuel filter, dizzy cap, condenser, coil, the timings been set, tappets gapped and I've got good compression. 

 

I did have an issue with NGK plugs. I'd fit a new set and they'd work fine but after a week of the car sitting, it would misfire.  

 

Now I've swapped them for Champion RN-9Y's the running of the car is better (it's back on 4 cylinders) but it won't idle or rev right. 

 

Any advice would be great!! I'm sure it's just the carb needing to be reset correctly but I'm at a stage where I don't know what I'm looking for and I don't know where a good mixture should be (not sure if that makes sense but hope it does!) 

 

Thanks in advance

 

Louis :) 

[sonscar]

Search Burlen Fuel Systems who have an excellent SU tuning guide.Have you overfilled the dashpot?it should be 10 mm or so down the inner tube,not up to the screw threads.Steve..

[Matteyboy1]

Thanks for your reply.

I’ll double check the dashpot and will give that website a go.

Cheers