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Old 07-01-2012, 12:07 AM   #21
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No batch fire is how your injectors are wired up. They fire 1 and 4 at the same time and 2 and 3. So Each cylinder gets fuel sent to it by the injector when the intake valve is open and also when closed.
Does it have to be that way?? Can a megasquirt make it not? Should I change it?
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Old 07-01-2012, 12:08 AM   #22
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Yes, mega squirt can run sequential, but you have to do wiring work. But you'll be able to run better injectors and should pick up some gas mileage.
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Old 07-01-2012, 02:53 AM   #23
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Yes, mega squirt can run sequential, but you have to do wiring work. But you'll be able to run better injectors and should pick up some gas mileage.
God I'm a noob. Sequential would be only having fuel dump in when needed right? not 1/4 and 2/3 or whatever it is. Also what do you mean better injectors? I didn't think the timing of when they squirted would change the quality of injectors. I just thought it was a matter of does it fit? (mechanically and electrically) and can the computer run it?
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Old 07-01-2012, 02:58 AM   #24
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First I've heard of the better injectors bit too, but the rest of the guys here seem to think its required.
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Old 07-01-2012, 03:05 AM   #25
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You can run ---- injectors. I am but if I had to spend the money again, I'd buy good ones for when I put a Reverant MS3 in my turbo car.
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Old 07-01-2012, 03:17 AM   #26
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No not the fact that there's better injectors, I know. I mean the fact that sequential is REQUIRED for better injectors.
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Old 07-01-2012, 03:33 AM   #27
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That's what got me. I get that there are better injectors, and you say you like the EV-14, but what i don't get is how it's better. I just don't understand, and I appreciate everyone input and patience with me. So I guess what i need to know is which would be the best injector for me. As I said before I have a 90 with megasurt pnp and BEGi shanghai turbo, inter-cooled and 10 PSI. And I just thought of this but would I need some sort of fuel pressure regulator and or new fuel pump?
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Old 07-01-2012, 04:53 AM   #28
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No you only need the injectors.

They atomise the fuel better, for more power, efficiency, stable air fuel ratios and better idle, and they respond faster, so they can be open and closed fully very fast.

older injectors trying to open and close very very fast a low fuel usage (idle) couldnt get right open and then closed in such a short period of time, so they didnt spray properly during idle and low street cruising rpm, making them harder to tune.

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Old 07-01-2012, 05:31 AM   #29
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The reason the EV14 Injector Dynamics units are so much better is because they remain linear down to less than 1.0ms pulsewidths. Injectors are not perfectly linear, so the quantity of fuel delivered with an 0.3ms pulsewidth is not 10% of the quantity delivered with a 3ms pulsewidth. The EV14 injectors that ID uses, however, remain linear down to much lower pulsewidths than other injectors, which means that despite their size, they will actually deliver small quantities of fuel more accurately than a smaller EV1 or EV6 injector.

Low-pulsewidth linearity is why an EV14-style ID1000 will typically idle and drive better than an EV1-style 550cc injector. The fact that the IDs are also E85 compatible and rated to something like 130psi of rail pressure is just icing on the cake. We won't use anything else in our cars, and ID725s will be standard equipment in our full turbo kits. They are a little pricey, but they truly are the last set of injectors you'll ever buy - the 725s will support over 400whp and the 1000s will flow enough fuel for over 600whp at stock fuel pressure.

ID's matching process is just as important as the low-PW linearity. ID dynamically matches each set to ensure that the flow is the same across the entire pulsewidth range, and not just at 100%DC where most people check. A batch of 100 off-the-shelf EV14 injectors might have a full-flow variance of ~1%, but the 5% PW flow might vary by 11%, which obviously wreaks havoc with your low-speed driveability. ID takes the time to match the injectors so that they flow within 1% EVERYWHERE, which makes it possible to obtain OEM driveability on injectors that are 4x the size of the stock units.

It's easy to talk about these injectors because they are so badass. You can do a quick Google search and read dozens of reviews written by enthusiasts and professional tuners alike raving about them in a wide variety of applications. It's not hard to stick a set of 1000cc injectors in a car - what's hard is making that car drive like the 1000s aren't there.

We have 725s and 1000s in stock. I can ship a set on Monday.

Last edited by Savington; 07-01-2012 at 05:42 AM.
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Old 07-01-2012, 12:41 PM   #30
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We have 725s and 1000s in stock. I can ship a set on Monday.
Wow that does sound good! Thank you for all that great info. I was also wondering, since you were talking about ID that is Injector Dynamics correct? Is that who you get them from? I ask because when I went to the their website ( Injector Dynamics - Main Menu ), when I click on the order button it links me to Injector Dynamics As you can see on here the 725s are going for $480 (for a set of 4 I think??) and $48 for the PnP adapters. Is that what yours go for? I only see the 1000s on your site. Also would you recommend the 1000s over the 725s for my application? or stick with the 725s as I'm currently planning. Again thanks a lot!
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Old 07-01-2012, 03:54 PM   #31
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Either injector will idle perfectly, so we typically sell the 1000s, but the 725s are there for people who will simply never need that much fuel. If you'd like to order the 725s just call me on Monday.

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Old 07-02-2012, 02:13 PM   #32
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No not the fact that there's better injectors, I know. I mean the fact that sequential is REQUIRED for better injectors.

So, do these EV14 injectors require sequential or can we stick with batch and still see an improvement?
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Old 07-02-2012, 02:28 PM   #33
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So, do these EV14 injectors require sequential or can we stick with batch and still see an improvement?
EV14 wil do a slightly better job in batch fuel as I understand it. To realize the full benefits, you should run sequential fuel. Also, read what Savington wrote about "linearality".
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Old 07-02-2012, 03:29 PM   #34
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I idled ID1000 in batch with no idle control valve no problem. It was better than idling 550cc rx7 injectors in same setup.

Now with sequential I can idle 17:1 afr
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Old 07-02-2012, 04:14 PM   #35
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I idled ID1000 in batch with no idle control valve no problem. It was better than idling 550cc rx7 injectors in same setup.

Now with sequential I can idle 17:1 afr
Is that with gasoline? And isn't that really lean?? I thought 14.7 AFR was ideal (Stoichiometric) Since we are on the subject of AFR again, what do I want to see for when it's in warm up enrichment? I think I'm around 12-13 AFR or so but I don't know if that that is right.
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Old 07-02-2012, 04:23 PM   #36
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Warmup enrichment typically start between 9:1 and 12:1 depending on the startup temp and slowly taper up into closed loop as the coolant comes up to temp, normally you should be able to achieve closed loop about about 150*F coolant temps, might be different depending on when your narrow band actually comes up to temp.

And you can idle at 17:1 for better gas mileage if you're able to reject the heat, the same with cruising at that afr.
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Old 07-02-2012, 04:27 PM   #37
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Warmup enrichment typically start between 9:1 and 12:1 depending on the startup temp and slowly taper up into closed loop as the coolant comes up to temp, normally you should be able to achieve closed loop about about 150*F coolant temps, might be different depending on when your narrow band actually comes up to temp.

And you can idle at 17:1 for better gas mileage if you're able to reject the heat, the same with cruising at that afr.
Good to know, also what do you mean by "reject the heat"?
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Old 07-02-2012, 04:31 PM   #38
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You create more heat in the combo chamber running lean like that. You either reject the heat or you melt things. You can reject the heat through the head, into the coolant, and out the radiator. And you can reject it out the exhaust valves and into the exhaust but that makes the valves and header hotter. You dont want to run it out the exhaust so you increase timing to keep egts down. But if you cant make it pass through the head fast enough and into the coolant fast enough bad things happen. Tuning this is way over your head.
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Old 07-02-2012, 04:38 PM   #39
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You create more heat in the combo chamber running lean like that. You either reject the heat or you melt things. You can reject the heat through the head, into the coolant, and out the radiator. And you can reject it out the exhaust valves and into the exhaust but that makes the valves and header hotter. You dont want to run it out the exhaust so you increase timing to keep egts down. But if you cant make it pass through the head fast enough and into the coolant fast enough bad things happen. Tuning this is way over your head.
I'm going to agree with you that this is over my head. I plan on leaving the tuning to Shawn at Church's Dyno. The guy comes highly recommended and really seems like he knows he stuff. I'm just trying to understand what is going on.
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Old 07-02-2012, 05:24 PM   #40
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I'm going to agree with you that this is over my head. I plan on leaving the tuning to Shawn at Church's Dyno. The guy comes highly recommended and really seems like he knows he stuff. I'm just trying to understand what is going on.
I remember about 3-4 years ago when all the California guys I hung out with talked about MS like it was the Commadore 64 of engine management. It seems that now everyone is tuning it.

I know that guy has a good reputation, but I promise you that no matter how good the tuner you will always have a superior tune if you tune the car yourself simply because you can put countless hours into perfection that you can't afford with an hourly rate.
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