quick questions - fueling probs
Turbo Mini Forums

had my car set up on the rolling road a few weeks back, came out running better but not perfect, 1st 2nd and 3rd are ok, can get on boost and the car takes off like the proverbial cat that has been scalded, 4th, forget it, seems to reach a certain point (about 3200rpm) and it just holds back, try putting your foot down to clear and it starts detonating (i think - strange mettalic rattling sound??!)

took it back and he reckoned the carb was knackered, ok no problem, one of the dashpot cover screws had snapped anyway so iwas replacing the carb as a matter of course

just wondering if anything else can be causing this lack of fuel, they tested the regulator while i was there and said that was ok.

im using 6mm i/d fuel lines, are these big enough?

also the pipe from the plenum to regulator, does it make a difference what size this is?? im using 8mm so it fits the regulator but it seems loose on the plenum

using an spi fuel tank and pump, is this ok?

thanks for the help and any other ideas you can throw at me

ryan

i would say that your fuel lines are too small,
should be using at least 8mm.
the strange mettalic rattling noise is pinking, you need to retard the timing a bit.
i'm sure others will be able to give better explanations.

““A turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.”” - Jeremy Clarkson

8mm pipes both ways,rr have a habit of leaning
off the mixture,if its running lean you will have
probs,

go for 8mm lines, the outlets on the spi are 8mm anyway

tank/pump should be ok.

If you want to block off both ends of the lean off pipe to see if it makes any difference then it will be fine. Just not quite as economical.

I recon you should have a larger return, puts less strain on the fuel pump - i use 8mm and 10mm return

Mine seems to be fine with 8mm both ways. I can turn the regulator right down to about 1.5psi so that shows there is very little restriction.

Depends what you can get hold of i guess

cheers, i had a feeling 6mm may be a bit small, have to redo them in 8mm

i did have a play with the timing and i can either get it running really well off boost but pinking all over the shop on, or the other way round, shit off boost, really rough, but great on boost and no pinking

i do believe them when they say its fuelling, or there is at least a problem with the fuel as they put the richest needle in that you can get, and it didnt make much difference to the c/o etc so deff not enough fuel getting through for some reason

ryan