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Old 07-07-2015, 07:41 PM   #21
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Quote:
Originally Posted by patsmx5 View Post
I gotta have a good idle on gasoline too. This is a street car and that's pretty important to me.

From what I'm gathering, it's either 1,300cc ID injectors, or add more injectors.

I'll look into that pump, thanks for the heads up!
My guess is there is a good chance you could still have a good idle at ~850RPM if the base fuel pressure is low enough since you have a referenced fuel pressure regulator. Worst case scenario you will idle at maybe 1000RPM but the behavior will still be good.

Food for thought:

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Old 07-07-2015, 08:12 PM   #22
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If you consider 1000rpm and 12.5-13.0afr at idle "normal", then yes the 1700's should be "normal"

Pat - don't worry about single digit timing, with that much boost it's not uncommon, besides you're still figuring out this setup, had you run more you'd likely have leaned out and broke something by now

You can always feed in more timing later. Once everything else is figured out.

PS: if the injectors are configured properly, then judging by that IDC i'd agree that pump is your problem right now
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Old 07-07-2015, 08:47 PM   #23
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Originally Posted by Arca_ex View Post
My guess is there is a good chance you could still have a good idle at ~850RPM if the base fuel pressure is low enough since you have a referenced fuel pressure regulator. Worst case scenario you will idle at maybe 1000RPM but the behavior will still be good.

Food for thought:

NEW Injector Dynamics ID2000 injector test - YouTube
Thanks for the info and vid. They do idle in that vid, but I will need to be able to idle at 14.7 for emissions. Part of my goal for this car is for it to pass emmissions so it has to be possible to idle at stoich. All the things it's going to take to make it pass emmissions is for another thread, I'll post about that when I do it.

Quote:
Originally Posted by 18psi View Post
If you consider 1000rpm and 12.5-13.0afr at idle "normal", then yes the 1700's should be "normal"

Pat - don't worry about single digit timing, with that much boost it's not uncommon, besides you're still figuring out this setup, had you run more you'd likely have leaned out and broke something by now

You can always feed in more timing later. Once everything else is figured out.

PS: if the injectors are configured properly, then judging by that IDC i'd agree that pump is your problem right now
Yes exactly! I'm keeping it safe and working the bugs out. That pull AITs were higher than I want and it leaned out.... I know I gotta get the fuel fixed before beating on it any more. And try to lower the air temps too. But I do know it wants more timing, I gave it 1 degree last night and it got slower... Then I looked and turned out I hit the minus sign not the plus. So fixed that (so now a change of +2, but only +1 from original map) and it gained quite a bit in power. Clearly not at MBT in the single digit timing.

Injectors are configured correctly as far as I know! I went from high 70's% Duty cycle all the way to mid 80's and AFRs didn't change, actually they got worse.... Clearly injectors can't get enough fuel, so it's gotta be the pump.
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Old 07-09-2015, 06:05 PM   #24
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Thanks for the info and vid. They do idle in that vid, but I will need to be able to idle at 14.7 for emissions. Part of my goal for this car is for it to pass emmissions so it has to be possible to idle at stoich. All the things it's going to take to make it pass emmissions is for another thread, I'll post about that when I do it.
According to ID they will idle at stoich on e85. What's to stop you from filling up with e85 before going to the sniffer?
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Old 07-09-2015, 06:11 PM   #25
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I want it to pass emissions all the time, pump gas or E85. To be honest I don't know if running on E85 would affect any of the emissions equipment/monitors, I simply don't know much about E85 regarding emissions.

As an update, I rewired the pump. I haven't run it to redline yet to see if it fixed it though, but just going to 7,000 the AFRs were richer than before, so it helped at least a little bit!
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Old 07-10-2015, 01:11 PM   #26
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Maybe run two pumps?

I've seen a few people (non miatas) run another pump by using a hose clamp to secure both the pumps together, and run a fitting on the top of the fuel pump holder deal.

Then on the fuel rail, they welded fittings on both ends, then tapped the fuel rail in the center as the new return line.

So each end had a feed to it, and center became the return line.
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Old 10-31-2015, 03:30 PM   #27
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Originally Posted by ihiryu View Post
Maybe run two pumps?

I've seen a few people (non miatas) run another pump by using a hose clamp to secure both the pumps together, and run a fitting on the top of the fuel pump holder deal.

Then on the fuel rail, they welded fittings on both ends, then tapped the fuel rail in the center as the new return line.

So each end had a feed to it, and center became the return line.
Car has twin HP walbro 255's now, that helped some at high loads my duty cycle dropped a bit. Also car is now E85 only.

I'm considering buying a set of ID 2000cc injectors for more fuel, at 22 PSI boost I'm at 88% duty cycle on the ID 1000's at 60 PSI base pressure. Is there any other injector in this size to consider? Looks like ID 2000's are stupid expensive.
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Old 10-31-2015, 03:57 PM   #28
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ID1300s. But they are stupider expensiver.

MS3 supports staged injection. Add some 600cc gt500 injectors?

Soviet hit 450whp on id100s. Are you sure you need more injector?
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Old 10-31-2015, 04:03 PM   #29
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you can easily run 70-80-90psi. cheapest upgrade ever, just turn the ****
even 100-120psi would likely still be ok
just make sure your lines are up to snuff
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Old 10-31-2015, 04:07 PM   #30
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Quote:
Originally Posted by aidandj View Post
ID1300s. But they are stupider expensiver.

MS3 supports staged injection. Add some 600cc gt500 injectors?

Soviet hit 450whp on id100s. Are you sure you need more injector?
22 PSI, 88% duty cycle on E85.



Staged injection would be nice, not a terrible idea. But I don't know of an easy way to add 4 more injectors to the flat top intake manifold. I don't have a way to weld aluminum, or machine the injector bungs.
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Old 10-31-2015, 04:08 PM   #31
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Originally Posted by 18psi View Post
you can easily run 70-80-90psi. cheapest upgrade ever, just turn the ****
even 100-120psi would likely still be ok
just make sure your lines are up to snuff
I have a 1:1 regulator right now, and I'm at 60 PSI base. I was thinking turn it for more fuel. Is it ok to daily a car running say, 90 PSI base fuel pressure? I tested my fuel lines for leaks by running it up to 90 PSI, man the fuel pump sounded pissed off at 90 PSI.
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Old 10-31-2015, 04:13 PM   #32
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90psi won't make your pumps happy. Run leaner? You should be able to on e85. You should be good until like 110% DC or something. 100 isn't actually max.

Go look at Soviets dyno thread. Space age turbo soviet era car or whatever.

I think he has logs.
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Old 10-31-2015, 04:14 PM   #33
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Nothing wrong with it. You will likely need to touch up the ve map, but if anything the id's like higher pressure supposedly it helps them atomize the mixture more efficiently

if twin wallys can't keep up with making 400whp (you're not even there yet) then there's another problem.
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Old 10-31-2015, 04:21 PM   #34
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It's the pressure that hurts. Not the flow. Twin 255s flow enough. But flow will drop as pressure increases. There is a table somewhere.

I researched this and wouldn't run above 100psi. The injectors can lock open.

ID has all this info in their website. You either need to run leaner, more duty or bigger injectors, or staged injection.
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Old 10-31-2015, 04:23 PM   #35
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Quote:
Originally Posted by 18psi View Post
you can easily run 70-80-90psi. cheapest upgrade ever, just turn the ****
even 100-120psi would likely still be ok
just make sure your lines are up to snuff
Add max boost to base pressure. IDs are rated to like 110psi.
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Old 10-31-2015, 04:25 PM   #36
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We make 400whp on subaru's and evo's all the time on a single wally and id1000's at base.
Now, I know his thupercharger is eating lots of power up, but:
You're telling me his car requires more fuel than TWO wally's can keep up with? What am I missing here?

Once Pat is past 400 then we can discuss further options.
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Old 10-31-2015, 04:30 PM   #37
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Originally Posted by 18psi View Post
We make 400whp on subaru's and evo's all the time on a single wally and id1000's at base.
Now, I know his thupercharger is eating lots of power up, but:
You're telling me his car requires more fuel than TWO wally's can keep up with? What am I missing here?

Once Pat is past 400 then we can discuss further options.
His pumps are fine. But running them at 90psi is going to shorten their life.

More injector would let him run less pressure.
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Old 10-31-2015, 04:36 PM   #38
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Nothing wrong with it. You will likely need to touch up the ve map, but if anything the id's like higher pressure supposedly it helps them atomize the mixture more efficiently

if twin wallys can't keep up with making 400whp (you're not even there yet) then there's another problem.
I'll bump the fuel pressure up as you say and see what that does. Go from there. The 255's can flow:
80 PSI: ~52 GPM
90 PSI: ~43 GPM
100 PSI: 34 GPM
110 PSI: 21 GPM
120 PSI: 12 GPM
130 PSI: Nothing

Link to pump graph:http://949racing.com/images/SuperMia...bro_255_HP.jpg

That is for 1 pump, so double that since twin pumps. Still I can't run these at 120 PSI and expect that to pump say 70 GPM, it won't happen. To get say, 80 GPM, the max pressure I can run is about 90 PSI, and that's 90 PSI total. If running 30 PSI boost for example, that puts me back at 60 PSI base....

If there is something else wrong, what could it be?
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Old 10-31-2015, 04:37 PM   #39
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Just bump to 70 and see. Then 80. I think even 90 it will still work and give you enough headroom for now

I suggest starting with easiest/cheapest approaches first, obviously. You can always throw spensive injectors at it later.

Is your AFR at 12 accross the board? Is your timing all solid? Let's see a virtual dyno pull and where she's at power wise. If you're sub 400 then you need to figure out what's wrong because you should easily make 400 on current fueling, at least I think so. (and is the sc really eating 100hp? I ask because in that case you're likely near the limit)
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Old 10-31-2015, 04:39 PM   #40
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Just bump to 70 and see. Then 80. I think even 90 it will still work and give you enough headroom for now
I will, no harm and no reason not to.

But I need more headroom, thus why I'm asking about bigger injectors.
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