View Poll Results: What are your 5.4L swap plans?
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Anyone intrested in 5.4L swaps, in here. Need you to opine.
#2591
the fuel pressure in mine (99+) is static at around 39-40. The 96-98 with returnless varied pressure according to vacuum. Since you have a 278 cam you're pulling significantly less idle vacuum (if I'm right.. could be wrong) and that would cause the fuel pressure to drop with the FPR thinking that it should be droppping pressure.
A couple turns of a FPR adj screw will fix the pressure at idle but I'm pretty sure that would also crank up pressure under full load and run you pig rich. Gunna have to call in the tuner guns on this one. Never had to deal with a cam that big on a return style fuel system.
Do you have any way of determining manifold vacuum at idle and WOT? That could help.
A 105mm I don't think would work well. It'd probably be pretty inefficient until very high rpm on a 2v. 76-80mm should be plenty with the right ratios.
A couple turns of a FPR adj screw will fix the pressure at idle but I'm pretty sure that would also crank up pressure under full load and run you pig rich. Gunna have to call in the tuner guns on this one. Never had to deal with a cam that big on a return style fuel system.
Do you have any way of determining manifold vacuum at idle and WOT? That could help.
A 105mm I don't think would work well. It'd probably be pretty inefficient until very high rpm on a 2v. 76-80mm should be plenty with the right ratios.
Last edited by r3dn3ck; 09-17-2007 at 08:07 AM.
#2593
with low vacuum the pressure rises to max, just like WOT. it varies with vacuum, so if he has 14 in/hg it could rise 5 psi from static idle.
12psi should barely run. something is wrong with either the gauge, regualtor, fuel filter, or fuel pump.
mine runs 55psi idle /65psi at WOT with a 255lph pump. but i have a custom MAF. so i need higher pressures to get A/F right open loop.
12psi should barely run. something is wrong with either the gauge, regualtor, fuel filter, or fuel pump.
mine runs 55psi idle /65psi at WOT with a 255lph pump. but i have a custom MAF. so i need higher pressures to get A/F right open loop.
#2605
i dynod it but the A/F was 18:1 to 16:1. my fuel pump was quitting. it's replaced now.
i'm going to the track dyno friday night.
this year with mismatched combo i ran
9.13 AT 79mph. that's about 240 rwhp. i lost .1 in 60ft from last year. the early combo had the 20" exhaust and cam timing jumped. totally lost low end and the 60' showed it.
judging by the dyno results and fixed A/F now, it will get into the 8's.
the launch technique i used last year was to flash it from idle. 2.0 60' with 3.08 gears.
early this year it had so little low end flashing didn't work. 2.44 60' times from an idle and 3.90 gears.
2.102 60' from fully stalled and 3.90 gears and low torque.
i never ran it with the 340 rwtq combo. but street runs put me several lengths on 05 gts'. that's what 60 rwtq more will do.
so what do i expect you say?
1.95 - 2.0 60' from idle(i have a lot of the torque back)
8.8 at 81 mph = 275rwhp
that's a .3/3mph gain over this years best low torque/hp run = 35rwhp more.
if so, my rwhp gains over the big torque dyno will be 25 rwhp. no matter what i lost 30+ rwtq from combo changes. so it's torque curve is more like an stock LS-1. just a little lower.
i'm going to the track dyno friday night.
this year with mismatched combo i ran
9.13 AT 79mph. that's about 240 rwhp. i lost .1 in 60ft from last year. the early combo had the 20" exhaust and cam timing jumped. totally lost low end and the 60' showed it.
judging by the dyno results and fixed A/F now, it will get into the 8's.
the launch technique i used last year was to flash it from idle. 2.0 60' with 3.08 gears.
early this year it had so little low end flashing didn't work. 2.44 60' times from an idle and 3.90 gears.
2.102 60' from fully stalled and 3.90 gears and low torque.
i never ran it with the 340 rwtq combo. but street runs put me several lengths on 05 gts'. that's what 60 rwtq more will do.
so what do i expect you say?
1.95 - 2.0 60' from idle(i have a lot of the torque back)
8.8 at 81 mph = 275rwhp
that's a .3/3mph gain over this years best low torque/hp run = 35rwhp more.
if so, my rwhp gains over the big torque dyno will be 25 rwhp. no matter what i lost 30+ rwtq from combo changes. so it's torque curve is more like an stock LS-1. just a little lower.
#2606
If anybody wanted to know, Kar Kraft is selling the Cobra R lower intake but be prepared for the price. Also, browsing through their site and read up on the Ford GT heads, looks like the new Bullitt is going to use those heads which probably means the new Bullitt is going to have a 5.4 in it.