Deathtrap13

I picked up these from a guy who sold his NC miata, he bought them as a 2006-08 Miata "Kit" from Skunk2, but the injectors themselves are just their standard 750cc product. Before you call me stupid for buying them... Just know they are 100$ a piece (new) and I paid him that for all 4. He had been setting on them for like almost 2 years and doesn't even have a miata anymore, AND he only used them for 2 dyno pulls and had to upgrade to bigger ones (or something like that...they are basically brand new).

I am just curious if anyone has any experience with these and could tell me anything about them. I just Installed Rev's enhanced MS2 a couple weeks ago and I have had a good experience so far, I am currently running Denso 23250-70080 Injectors (305cc Supra injectors) and only running up to 9-10 PSI of boost. Honestly I am actually not having any issues with the 305's....I have a pretty steady idle and AFR's are good. I've only been street tuning with VEAL and tweaking my AFR table a bit, and I'm getting consistent results and the car runs pretty damn smooth.

I was told on the Mazda-speed.com forums that I would find the 305's to be less than acceptable for what I wanted and they are doing fine, but I do know life would be easier with some EV14's.
In fact, we have a 5-page thread going that was supposed to be about my ECU installation, and resulted in us talking about injector dynamics for 4 weeks
http://www.mazda-speed.com/forum2/in...c,32037.0.html





Anyway, here is the description directly from Skunk2:
"Grams standard fuel injectors are chosen by professional motorsports and performance enthusiasts because of their quality, consistency, value, and ease of use. They were designed primarily to be used with Gasoline based fuels, however may be used with alcohol based fuels with the understanding that the fuel system must be regularly flushed out and stored with gasoline to minimize flow losses associated with the use of alcohol on a consistent basis."
Features & Benefits
• Cold-machined tips for high-precision operation
• Compatible with all known fuels including gasoline, methanol, and ethanol
• Made from Bosch® EV14 Standard housings
• EV6-USCAR electrical connector
• Flowed and balanced to within 1% for consistency
• Precise fuel metering up to 118 psi (8 bar)
• Pressure tested up to 220 psi (15.16 bar)
• Lightweight valve needle and ultra-fast solenoid
• Superior valve ball and modified nozzles
• Improved atomization for greater combustion efficiency and reduced emissions
• Unmatched cylinder-to-cylinder consistency
• Leak-free operation and optimal performance
• High-impedance design (no resistor box required)
• Over-molded one-piece design for added reliability and simplicity.
• Direct OEM replacement application specific kits for variety of makes and models
• Comes with an injector latency data to accurately set up aftermarket ECU

Link to 750 cc Std injector page >>> http://store.skunk2.com/grams/fuel-injectors/grams-performance-750cc-min-standard-fuel-injectors.html

Here is what I got:


Then I bought Flow Force's Miata Adapter Kit...
It included top hats, O-Rings, connectors and spacers...
so they fit exactly as regular miata denso injectors fit.




I should have been a photographer....

Anyway...I'm contemplating If I should try these out or if I should sell these to a honda owner for 300$ and get the DW 650's that everybody on here loves and trusts... I have no idea if anyone has had any success with these or if they will act the same as any modified EV14 and be fine.

Lokiel

Any modern injector will be better than the 305cc Supra injectors - see DaveB's photo of the injector spray patterns in Injectors comparison , the 305cc injector fuel atomisation is rubbish and is actually jetted out in several distinct streams.

You got your injectors for a good price so if you can find their Dead Times, use them.

Personally I'd sell them for $$$profit and buy EV14s or ID725/1000s since I know I'd get them at some point anyway - saves time dicking around with installing injectors and tuning twice.

18psi

iTrader: (76)

no one here loves dw650's
everyone loves ID's, and the FF's are starting to become pretty popular.

The problem with injectors that not many use and is for a different application, is that you're all on your own figuring them out. Most don't realize how important support is until they waste days/weeks/months figuring out how to get something to work when another part coulda been installed and tuned in a matter of a couple hours.

But either way, they're still better than the janky supra 305's which are even older and worse than your stock injectors were.

If you can make a profit on them, sell them and buy ID's. Otherwise good luck

Deathtrap13

Thanks 18psi. I refer to your threads a lot.

I really think I should sell them and get somthing that you guys use more often and there is data for here on the forum. But I would hate to know that they work fine and I just ditch them for no reason. I put this up... hoping that someone using them would chime in and tell me if they work ok.

A big concern we discussed in my mazdaspeed thread was about spray pattern, and how stock mazda injectors spray in a dual pencil form, which lands pressurized fuel right on the back of the valves in the head...I tested these today and cant tell if they are in that same formation....But I was at 80psi, so maybe they are. they do lay out a similar pattern...if not close...but it looks almost like full cone to me.

The frustrating thing is that no one on this forum has a word to say about these injectors, and they make injectors for several miata applications.

Deathtrap13

^Shopping for Injectors^
Rolled across Flow Force's add on ebay for their basic injector kit.... this is a direct quote.
"This is a high performance, high volume fuel injector. Fuel delivery is from a multi-hole disc which incorporates a wide cone-shape spray pattern for maximum fuel atomization for modern single-valve and multi-valve engines. These injectors will function at fuel rail pressures of up to 7 bar"

Deathtrap13

FF's evidently have the same spray pattern and if thats the case I'm just going to try them

What would the dead time be? Do I used the value on this chart?

It says "Dead Time" but I don't know for sure the operating pressure and voltage for our cars.

https://www.miataturbo.net/attachment.php?attachmentid=171436&dateline=146324 3528