Alternative Fuel Injectors

[dfink]

Originally posted by RickM
Troy, Thanks for posting Stan Weiss's FI spec info.

Looks like the closest injector replacement is the Holley 520-8004 or 520-8005.

However, Bosch replacements can be had for under $65.

Can't find the Holley number internet search is blank and so is the Holley web site. If I follow their number format that would a 80lb per hour injector.

And still looking for the place and part number for a bosch replacement. Or anyother brand that will work that is cheap and meets the specs. I must not be asking the question correctly. Maybe there is not part number and you just have to call and ask the manufacturer if they have one that will work. Seems they would list it if they did.

Yes the 944 used the same injector
930-606-120-00 Fuel Injector, 4 Per Car, 944 (2/85-88), 924S (1987-88)

I did find the injector Troy listed Accel ACC-151255
Accel Fuel Injectors
Fuel Injector, 255cc/ minute, Low Impedance, Honda, 1.5/ 1.6/ 2.0/ 2.2/ 2.7L, Each $65.95

[dfink]

In looking at the accel ACC-151255 injectors they don't have the same type of end so no really I have no idea if they would work.

The Accel



The Bosch

[RickM]

If you look at the chart included in Troy's link the Holley specs are listed. From what I gather they're in the $89 each ballpark. The Bosch replacement is as low as $64.95. Not sure if it's for new or refurb though.

[TimT]

You are making this exercise much more difficult than it need be.

The accel injector you pictured is an example of one of many other injectors that will work for this application

[dfink]

Originally posted by TimT
You are making this exercise much more difficult than it need be.

The accel injector you pictured is an example of one of many other injectors that will work for this application

You are correct this is difficult for those of us that don't work with it everyday. We have three choices.

1: Buy an exact new part.
2: Search the internet for something that says it is a replacement
3: Come here and find out what to get.

1: Works fine but is expensive
2: I can find no place that in their list of items directly lists a replacement. (remember I don't have the knowledge to guess)
3: This is what we are doing but I can't seem to get a direct answer. Everyone says "Several are made" "We have used these" but no specifics are given (remember I am stupid and if the search doesn't say it is for a 84-89 3.2 then I have no way to tell if they will work) In the example of the accel vs the original they don't even look the same so again being un-informed I am not probably going to think they will work.
The guys that say they are using some other brand are you using it on a stock 84-89 3.2 or some modified version that takes more info than "shop and drop"

I don't even know why I care anymore other than to find a specific answer for the next guy. I have nice new $600 injectors that were not in my budget sitting in my car because at the time that is all I could find that would fit so I will not be trying any of the suggested replacements. But for the next guy trying to get by a little cheaper a "specific brand and part number" might be helpful.

[Zeke]

Originally posted by dfink


I don't even know why I care anymore other than to find a specific answer for the next guy. I have nice new $600 injectors that were not in my budget sitting in my car because at the time that is all I could find that would fit so I will not be trying any of the suggested replacements. But for the next guy trying to get by a little cheaper a "specific brand and part number" might be helpful.

Well, I, for one, appreciate the thread.

[Jeff Alton]

The accel injectors you pictured are the ones I am using in my 3.4 with ITB's. (36lb) They have a different spray pattern. Bosch uses a needle and seat type single spray while the accel uses three outputs that spray together.....


I don't have the part number handy, and each lb rating has a different number, but for the next guy all he has to do is go to the accel website or Summit or Jegs and search Bosch style injector and all the diffenent lb rating ones will show up.


Cheers

[dfink]

Originally posted by catca

I don't have the part number handy, and each lb rating has a different number, but for the next guy all he has to do is go to the accel website or Summit or Jegs and search Bosch style injector and all the different lb rating ones will show up.


Cheers

It's not that easy or this thread would have never started. I have searched all the web sites listed and each time I run into something that makes the injector not suitable. Either the impedance is high (this is the most common) or the body is not the same several of the companies offer a 24# low impedance injector but it is not the pintel type of injector and it appears that the o-rings are in a different part of the lower body. So far the only pintel type low impedance injector I have found is the Bosch.

[dfink]

If you want to know about fuel injectors this site is very interesting.

Robie The Robot Injector Guide

[RickM]

Excellent site. Thanks for sharing.

[stlrj]

For what it's worth, I've been using a set of saturated injectors on my '86 3.2 for years and the only mod I had to make to have them work was to add a start enrichment relay on the head temp sensor circuit that added an extra 1k resistance to get my engine started on a warm startup.


Cheers,

Joe
74 911 w/ 86 3.2

[TroyGT]

That's interesting, especially if you go to Dfink's link... it clearly says that a saturated injector can't handle the current supplied by our peak and hold system.

-Troy

[stlrj]

What's even more interesting, I've been trying different sets of saturated injectors from GM Multec to Mopar for years without a problem.

Only now I find out they won't work...

Anyway, I'm staying with my saturated Mopars no matter what anybody says.

Besides, the high impedance of the saturated injectors will limit the current ( Ohms Law ) on the DME injector drivers so they'll run cooler and last longer IMHO.

Cheers,

Joe

[JohnJL]

I bought a set of 26# from Summit and have enjoyed them in my race car. They are low-ompedence and fit directly into the alu 3.2 intake. I drive them with an aftermarket ECU.

[dfink]

All of these posts are interesting and I have learned alot about fuel injectors in general. Still however no one has offered up a cheap direct replacement for the original injectors without some form of modification or non stock application ie race engine
Though many suggest it exisists no one has posted a manufacturer and part number for a $30.00 direct replacement. Point is if you only have 1 or 2 bad and need to replace them what do you get.
Most don't want to modify the electronics. I wouldn't even know where to begin. And I am not likely to install something that every injector site out there says not to use.
JohnJL - I did a search at summitracing.com and could not find a 26# low impedance peak and hold injector. Perhaps I am just not looking correctly.

[88911coupe]

I agree with dfink, there are those on the board with skills that allow experimentation and there are people like me...

[s5uewf]

I find this thread very interesting, and I have a few questions after reading (for the injector wizards here):

- I have a 3.4Liter rebuild now with a SW chip, and A/F is on the money.

- If I upgrade the injectors, will I see more power as a result, even though the A/F ratio is good now?

- If I upgrade the injectors to a higher flow rate, will the stock fuel pump be able to maintain higher pressure required for higher flow injectors?

- Any advice on what the optimum flow rate (pounds rating) would be for injectors to be used in a 3.4L engine?

[TimT]

- I have a 3.4Liter rebuild now with a SW chip, and A/F is on the money.

good

- If I upgrade the injectors, will I see more power as a result, even though the A/F ratio is good now?

no all changing injectors will do is lighten your wallet

- If I upgrade the injectors to a higher flow rate, will the stock fuel pump be able to maintain higher pressure required for higher flow injectors?

Yes the fuel pump(s) will keep up. Injectors are typically specified at 3 bar pressure. Unless you get huge injectors your ok, but since you don't need new injectors, moot point

- Any advice on what the optimum flow rate (pounds rating) would be for injectors to be used in a 3.4L engine?

Injector selection is based on power output, BSFC (brake specific fuel consumption), duty cycle and number of injectors. BSFC is an assumption unless you measure it on a dyno, accepted values for NA engines are 0.4-0.5 use 0.45, injector duty cycle is taken at 80-85%


flow rate=(HP X BSFC)/ (Number of injectors X Injector duty cycle)

The only variable missing is the HP output of your engine

[TroyGT]

stlrj (Joe)... I'm intrigued... in your experimentations with various injectors. Have you found any that were drop replacements without any additional modifications? I think everyone here is looking for a cheap, comparable, drop in and go solution. Well, I know I am. I'm not Bosch biggot, if there's something out there just as good. However, I'm no whiz at experimentation without guidance... as most people who have worked with me on this board are aware of... but I'm game to try something new if I don't have to alter much. So, what all have you found in your experiments?

-Troy

[stlrj]

Troy,

As I said in my earlier post, the only mod I had to make to have them work was to add a start enrichment relay on the head temp sensor circuit that added an extra 1k resistance to get my engine started on a warm startup.

If you're still game at this point, I still had to play with the air flow meter mixture to dial in the injectors...more experimentation.

After all that you could benefit from more low end torque, gas mileage, throttle response, smoother idle...all the benefits that the EFI converts are looking for without the cost or headaches of reinventing the wheel.

Cheers,

Joe