What Injectors/Coils are teams using?

[ethanL007]

Hey, I searched on the forum and couldn't find this topic. What are some of you guys using for coils and injectors, and what are the resistances? We are looking into F4i injectors and GSXR coils. Anybody have any horrid experiences with either of these?

Ethan Lessard
Team Captain
UNH Precision Racing
www.domesticpc.com/fsae (http://www.domesticpc.com/fsae)

[ethanL007]

Hey, I searched on the forum and couldn't find this topic. What are some of you guys using for coils and injectors, and what are the resistances? We are looking into F4i injectors and GSXR coils. Anybody have any horrid experiences with either of these?

Ethan Lessard
Team Captain
UNH Precision Racing
www.domesticpc.com/fsae (http://www.domesticpc.com/fsae)

[B Lewis @ PE Engine Management]

Hey Ethan,

We are running F4I injectors on one of our dyno engines (F3) and they seem to work well. Can't speak for the GSXR coils but I think they may be the same Denso units as on the F4. The number on the set I have here is 129700-3881. Can anyone else verify?

Brian Lewis
Performance Electronics, Ltd.
www.pe-ltd.com (http://www.pe-ltd.com)
"Complete Engine Management Systems"

[ben]

We use GSXR 750 injectors. Not sure about the coil I'm afraid.

Ben

University of Birmingham
www.ubracing.co.uk (http://www.ubracing.co.uk)

[joeinthedark]

Ethan

Last years car used 210 cc/min injectors, but after doing some calculations this seems really big. I was thinking of using 120. I will probably get them see how they compare.

[Charlie]

Just goes to show you, beware of internet advice. http://fsae.com/groupee_common/emoticons/icon_eek.gif

-Charlie Ping
Auburn University FSAE (http://eng.auburn.edu/organizations/SAE/AUFSAE)
5th Overall Detroit 2003
? Overall Aussie 2003. http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Frank]

bosch 130's last year (expensive)

bosch 155's this year (they were free), and had no probs

stock f3 coils, group fire

[ethanL007]

it looks like we are going with the GSXR coil on plugs, wasted spark.

F4i injectors, group fired.

all from the PE-LTD ECU.

Ethan Lessard
Team Captain
UNH Precision Racing
www.domesticpc.com/fsae (http://www.domesticpc.com/fsae)

[Chris Boyden]

For teams looking for low-impedance and high impedance injectors, RC-Engineering is a good place to go. They precision grind the injectors they might help you with the price because of FSAE. We used 155cc/min RC low impedance injectors on the '03 car. We'll use the stock F4i injectors this year and the stock coils. As for sizing injectors, RC -Engineering and MSD ignition have some the basic formulas needed for sizing the injectors based on HP output on the web. And as Charlie points out beware of other injector sizing methods.

[Ben Beacock]

Does anyone know the drive current for the GSXR coil on plugs? Just wondering if I can get away with simple transistor switching or if I should use a mosfet drive circuit.

Ben

Ben Beacock
Co-Manager
2004 Gryphon Racing - University of Guelph

[Charlie]

Your main injector constraint besides size is minimum pulsewidth time, which can cause problems at low speed. After all these engines are not very large and not very efficient at low RPM, so they require veyr little fuel. Once you trigger an injector, it stays open for a set amount of time before it closes, regardless of how long the solenoid has power. So a bigger injector will let too much fuel out.

If you are sequential, you can use a bigger injector, because they only trigger every 2 crank revs, instead of each crank rev. This means the fuel is in one shot instead of 2, and you can effectively give the cylinder less fuel because you are only limited to one minimum pulsewidth.

The stock F4i injectors are intended for sequential operation, and probably too large for batch fire. In fact, I believe they are 'freakin huge'. http://fsae.com/groupee_common/emoticons/icon_wink.gif

-Charlie Ping
Auburn University FSAE (http://eng.auburn.edu/organizations/SAE/AUFSAE)
5th Overall Detroit 2003
? Overall Aussie 2003. http://fsae.com/groupee_common/emoticons/icon_smile.gif

[B Lewis @ PE Engine Management]

We've had very good luck using the stock Honda injectors in batch mode. The stock units have a pretty good frequency response which allows for excellent low speed operation.

Brian Lewis
Performance Electronics, Ltd.
www.pe-ltd.com (http://www.pe-ltd.com)
"Complete Engine Management Systems for $798"

[Charlie]

That's interesting; we have tried automotive injectors that were significantly smaller than the Honda injectors and they still had trouble at low speed operation in batch fire. Of course they were totally different injector designs.

-Charlie Ping
Auburn University FSAE (http://eng.auburn.edu/organizations/SAE/AUFSAE)
5th Overall Detroit 2003
? Overall Aussie 2003. http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Chris Boyden]

The low impedance 155 cc/min from RC Engineeering that we used last year were just barely small enough. At idle we were at 1.8 msec pulsewidth, just above the minimum turn on time. But, low impedance injectors require peak and hold drivers on the computer, so that has to be considered.

Any body have a flow rating for the Honda injectors? I believe that the stock Honda Pressure Regulator is set at 50 psi. Even if the injectors were too big, the pressure could be dropped with an adjustable regulator. But that adds to the cost.

[Detroit_Muscle]

We use the F4i injectors on the engine. The approx flow rate is 140 cc/min. The stock pressure is 50 psi.

The coils we are using are denso coils which are on the F4i. you can also use them on F2 or F3 motors provided you have a good coil driver circuit. I have a schematic for one we have used and has worked well for us. Just make sure you're dwell time isnt too long, otherwise you'll fry them. I can tell you that one from experience.

Sami Ahmed
UMD Racing
Team FSAE

"Drive it like you stole it."

[Jarrod]

1988 holden camira, haven't let us down in 4 years

[Detroit_Muscle]

Might you let us know the US equivalent of the Holden Camira, since it might be a GM derivative?

Sami Ahmed
UMD Racing
Team FSAE

"Drive it like you stole it."

[Jarrod]

camira was an Australian designed car (i think) and is not a car with a great history for quality or performance. The late camiras used the GM family 2 engine, still used in Daewoos in australia.
full set of injectors - A$40 (US$20)
no difference between a current bosch motorsport unit and these on the dyno

for an idea of what a camira is -http://members2.easyspace.com/hotholdens/model/camira_1982-89.html

[gug]

glad to see that site tells the truth Jarrod!

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> Year of Introduction: 1982
Engines: GM Family II "camtech" 1.6 OHC engine,
Transmissions: 4 speed manual, 5 speed manual, 3 speed TH125 Hydramatic automatic
Claimed Maximum Power:64 kW claimed power
Performance: N/A
Total Production:85,725 produced
Prices at release - SL sedan $8,220 SL/E wagon $11,825 <HR></BLOCKQUOTE> http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

- if it isnt coming, you need a bigger tool.

[Grant Mahler]

Digging up an old thread instead of starting anew.

What coils are people using these days?

Also, anyone know any lower limit to impedance for Megasquirt 2?

I heard from a buddy who recently had problems, that the PE box is only designed for coils down to 0.4ohms, but hadn't heard of such a limit for MS2. Any help?

[Grant Mahler]

nevermind.