Upgrading my fuel injectors and some other stuff.

[Anonymous]

I was wondering if when I upgrade my fuel injectors, in my 96' 300, if I must also upgrade my ECU ( chip-it) and if I must upgrade my fuel pressure regulator? If you could let me know i would be much obliged. thanx.

Chris

 

[StrangeRanger]

On a 96 you have mass-air so the rules are a bit different. You will need to have your mass air meter re-calibrated for the new injectors. You can either use your stock regulator and have the meter recalibrated for your new injectors working at the higher pressure of the 300's fuel system, adapt a regulator from a 302 and have the meter calibrated for the new injectors that pressure or use an adjustable regulator and have the meter recalibrated at a probable set pressure. FWIW I could not find an adjustable regulator that could be fitted to the rails of a '96, they are substantially different from the older S/D trucks.

Why are you changing the injectors? Are you making other modifications to the engine? If you're not doing other work, the bigger injectors may not be worth the effort. The 300 is limited as much by the stock head and cam as it is by the fuel system. Unless you re-work the head and get more valve lift and/or duration, you're not going to increase the HP simply by adding bigger injectors.

 

[Anonymous]

Thanx, I already have an appointment to have my mass air meter re-calibrated, i was just wondering if i need to get a chip because i am aloso putting a larger cam, roller rockers, chopping my deck(head).010, headers, injectors, that kinda stuff. Oh and as of today, having my trans re-built, thank you mazda/ford .

 

[StrangeRanger]

While you've got the head off, rework the bowls and clean up the ports. They are the bottleneck in the 300 making power.

 

[Modifyre]

Speaking of that SR I just bought my die grinder kit kit today and stripped the valves outta the head last night (another late nighter)... I read some of the previous msgs on porting; I am putting an EFI head, intake and exhaust manifolds with a Megasquirt controlling it. How much work do I do in the bowl? I was just gonna unshroud the valves a bit (you can see a hunk of iron in the way of the exhaust port) and round off the edges a bit. Leave it a little rough in the intake, polish the exhaust ports, match port the lower intake with the head with the help of the gaskets, and match the lower and upper intake to the gasket as well. Which brings me to another question. There's a funny bulge of carbon (everything's coated good) on the top corner of the intake ports where the injectors would be... Do I grind this out a bit? Will this make the fuel spray outward a little better? Also having done all that work along with grinding the intake for a 302 TB can I put 19 or 24 lb injectors in? Which ones would be best? I may be puttin a cam in at the same time and later I will hopefully be adding a supercharger...

Sorry for rambling.. Gotta grab another coffee... Bye!