Straight Gas or Fuel Injection - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

crzyxf · 08-07-2002, 18:42

i have a carby xf and i want performance (hey who doesn't). I would like to know whether i should go straight gas or fuel injection.

With which setup can i do the most mods too.

BDA55 · 08-07-2002, 18:49

Gas is the way to go, especially if you are building a motor from scratch. lpg has a higher octane, amost zero emissions and is relatively cheap. downside is ugly gas convertor, and low calorific value of lpg (you will use more gas than petrol). contact Gas Research Australia, they will point you in the right direction and have dedicated gas cams etc.

FMXer's XF ute · 08-08-2002, 03:16

what about both

it would scream then and you will get the best of both worlds

umm i thought that the had lowered the octane level in the gas today

BDA55 · 08-08-2002, 15:53

the octane in most lpg is still over 100 ron, don't run duel fuel!!! Petrol and lpg have different properties, so you have to set the engine up with both in mind, you will lose performance. liquid gas injection has not yet been sorted to my knowledge, but would be the ultimate street hi-po fuel.

tonyk · 08-09-2002, 00:50

Straight gas although I think a sidedraught ported and polished IMPCO 425, on a common plenum feeding 4 inch ram tubes will deliver more than the GRA for less money. IMO :)
Spend the time on the head opening the exhaust up and polishing everything. A cam (plus 0.5") favouring exhaust by several degrees is needed too. LPG will quiet a big cam also so it will idle when the same motor on fuel would not. Good extractors with 1 7/8 primaries matched to the exhaust ports and a single 3" system. If you go straight gas enquire about getting an emissions exemption too. You have to take out the petrol tank but you dont need any more cat or pollution plumbing. 4* CO is the emissions mark which is easily achieved.