67 twin turbo dart
- Thread starter Matts440
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Matts440
Well-Known Member
Fuel is stable as far as I can tell just has been leaning out, I installed a light to let me know when the second full pump comes on. Base fuel is 32 and a 1:1 regulator, unless the Mallory regulator isn't keeping up. Just added +2.0 from 4500-500, +4.0 5000-6000 and +6.0 to 6-7, should I put more into it?
Matts440
Well-Known Member
They are already 210lb injectors. But will check that out
Matts440
Well-Known Member
I have it set to 12.5 target, wide band show 22 which then the safety kicks in and shuts it down. Here's the current fuel setting just added more fuel but now that's its raining, can go out now.
Matts440
Well-Known Member
Just went out in the garage and idle psi is 32, and when revving it psi jumps to 40, its good up to 100psi, fuel pump Info 400LPH (100 gph) at 40 PSI, 340LPH (90 gph) at 73 PSI, and 270LPH (71 gph) at 120 PSI.
TT5.9mag
Two atmospheres are better than one
You need to log fuel pressure and check it under load.
Matts440
Well-Known Member
Sun came out and dried the roads, went for a spin, found a open road, fuel load % at idle was 40% then driving when I got on it my son said the highest he saw was 55% fuel load going up to 4 grand.
I may be wrong but 32PSI is really low. I’m not boosted and use a corvette regulator/filter and it runs around 58psi. I’ve heard of some efi running 46-48, never 32. Curious why you’re running that.
Matts440
Well-Known Member
To be honest that were the dyno shop told me to start at didn't even think about upping the fuel pressure, like I said this is why I ask questions, first time efi. You all are awesome,
Matts440
Well-Known Member
If I get a chance I'll try going out again tonight if not tomorrow and just see how it does with the more fuel psi, the injectors are rated at 43.5 psi for the 210 lbs.
TT5.9mag
Two atmospheres are better than one
Almost every aftermarket ecu wants 43.5 base pressure. Some want 58. It doesn’t really matter as long as the injectors are scaled properly. The shop may have had issues getting your 210lb injectors idling clean at anything higher than 32. I just want to make sure that your regulator is boost referenced and rising with boost. If it’s not, or dropping fuel pressure with load you’ll burn it up.
Matts440
Well-Known Member
It does rise with boost, and makes sense, well at that time I had the versafueler on it causing issues driving the injector back when it was there, when I brought it home the last time I took that off and runs better. Ill give it a drive tomorrow, with a load it rises and revving it also can watch it rise on the rail gauge
Report back with a datalog. RPM, fuel pressure, inj duty cycle, MAP, and AFR.
Matts440
Well-Known Member
I'm not sure which logger that is on, I used the engine one but it has just spark and injectors but just shows on or off. Any in site?
Matts440
Well-Known Member
If its the same as the fuel load was 52% or if that corolates to the same fuel pressure.
You should be able to log all the data off the ecu with a laptop and tuner studio. Then you can open it with megalog viewer HD.
Matts440
Well-Known Member
I did do a data log and viewed through megalog, this was with engine + map press loaded set up. I'll have to back trace the wire to see which on was used for the fuel pressure sensor.
TT5.9mag
Two atmospheres are better than one
If your base FP is 32 then at 4500 with 5 psi at 1:1 in the regulator you should have 37 psi FP.
TT5.9mag
Two atmospheres are better than one
If you have a FP sensor that’s perfect, just find out how to add that trace to your log. Honestly a FP gauge (with an isolator) in the car isn’t a bad idea when you get up to the power level your stuff is capable of. A drop in pressure on big boost is a sure fire way to leave parts on the ground.
Matts440
Well-Known Member
Not a bad idea, didn't think of that, will start looking into a kit for that, just another gauge to add lol thank god for roll bar mounted ones. Speed hut does have a all electric on that I could mount their sensor on the rail. Thanks for all the great advise my friend.
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Here's my opinion, which isn't worth $hit since I have zero experience tuning a turbo combination.
Isn't a 210lb injector good for 1200-1500HP? I don't know how much HP your motor makes NA, but let's assume you need to put about 20psi boost in that thing to get anywhere close to that power. You're seeing 5psi with a duty cycle of 55%. The numbers don't add up for me. Heck even at idle, I wouldn't expect to see 40%! This higher duty cycle has to be related to the lower than suggested fuel psi. I'm sure this is fine at lower cruising RPM, but what happens when you get into bigger boost and your duty cycle is maxed out and the injector can't move enough fuel with the lower pressure. You would have to hit 11.5 psi before you even get to the designed rating of the injector. That's territory I wouldn't want to play in. I'm sticking with my recommendation to increase base fuel psi. I don't know if the fuel table automatically re-scale if you change injector data- someone else would have to answer that. If they don't re-scale, you will be practically starting from zero again on your fuel maps.
Isn't a 210lb injector good for 1200-1500HP? I don't know how much HP your motor makes NA, but let's assume you need to put about 20psi boost in that thing to get anywhere close to that power. You're seeing 5psi with a duty cycle of 55%. The numbers don't add up for me. Heck even at idle, I wouldn't expect to see 40%! This higher duty cycle has to be related to the lower than suggested fuel psi. I'm sure this is fine at lower cruising RPM, but what happens when you get into bigger boost and your duty cycle is maxed out and the injector can't move enough fuel with the lower pressure. You would have to hit 11.5 psi before you even get to the designed rating of the injector. That's territory I wouldn't want to play in. I'm sticking with my recommendation to increase base fuel psi. I don't know if the fuel table automatically re-scale if you change injector data- someone else would have to answer that. If they don't re-scale, you will be practically starting from zero again on your fuel maps.
Matts440
Well-Known Member
I did adjust the psi to 43, and yes I will have to rescale manually which is fine, I'll try and get it out today and see, have to make sure I'm back in time to take my oldest to get braces put on today.
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