Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > Porsche 911 Technical Forum


Reply
 
LinkBack Thread Tools Rating: Thread Rating: 6 votes, 3.67 average.
Author
Thread Post New Thread    Reply
Registered
 
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,725
Just for fun, I switched out the high imp...703 Caravan injectors with the GM 2.3L low imp Multec injectors PN 17103001 that I tried in my earlier 86 3.2 Carrera engine where warm starting was a problem and performance seemed down when compared to the stock injectors. This time, on my 87 Carrera, these Multecs performed amazingly. From an instantaneous startup, idle was noticeably smoother, off the line, mid range and top end even stronger. Totally unexpected from injectors with the wrong flow rate of 19.6# compared to the correct 22# stock ...158 Carrera injector. The only explanation I can think of was that my earlier 86 3.2 fuel pressure may have been off due to wear and my air flow meter may have been out of adjustment.

19.6# low imp Multec
http://www.witchhunter.com/flowdatapix/rp17103001.jpg

Here is a visual comparison between a Bosch and Multec injector:
https://www.google.com/search?q=Multec+mpi+injector+applications&biw=1280&bih=852&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwinr-mcwMfJAhUizIMKHaFKAW4QsAQIUQ#imgrc=o_WLtH1SBuZS9M% 3A

GM Injector Characterization
http://injectordynamics.com/articles/gm-injector-characterization/

Multec Injector Vehicle Fitment
http://www.**********/gb-remanufacturing/multi-port-multec-style-fuel-injector-mpn-832-11116.html

Frequently Asked Questions
http://fuelinjectorclinic.com/faqs/#3

I can only conclude that trying alternative injectors on our aging Carreras is extremely difficult and nearly impossible due to inconsistencies in air flow meter signal or fuel pressure and may be difficult to achieve the same level of success that I have due to these factors. Also, the level of skill required of the installer to be capable of making the necessary adjustments to the air flow meter to match the new injectors is not easily found in most tuners today. In other words, it's not a matter of just dropping in these injectors and driving off, which would be true of any alternative injector.



Cheers,

Joe
Senior PCA member since 1976


Last edited by stlrj; 12-07-2015 at 08:02 PM..
Old 12-06-2015, 06:43 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #301 (permalink)
Registered User
 
douglas bray's Avatar
 
Join Date: Nov 2009
Location: Rancho Cucamonga
Posts: 666
Anyone have any input on the Bosch 715 injectors I'm about to install into my car. They flow a tad bit more than the 784 that I've been in love with for the last 1,500 miles.

Installing a wide band O2 meter first.....
Old 07-10-2017, 02:14 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #302 (permalink)
Registered User
 
douglas bray's Avatar
 
Join Date: Nov 2009
Location: Rancho Cucamonga
Posts: 666
Quote:
Originally Posted by scarceller View Post
This thread has details on drop in replacements. The ones I know 100% fit and run fine are these bosch numbers:
0-280-150-364 Special all metal tip
This one should also work:
0-280-150-360

I run the 364s in my car and several others in this thread do also without issue.
You need to be very careful with just dropping in any old injector that meets the flow rate. The flow rate matters but so does the injector offset or dead time, this is the amount of time it takes the injector to fully open and to fully close. The DME compensates and calculates from the time built into the software for the stock injectors. So when you decide to pick another replacement injector this must also be accounted for.

The above 364 and 360 have very near offset times to the stock injector.

Also, Steve is correct that stock injectors don't inhibit performance they work just fine at hi flow rates. The modern injectors just atomize fuel somewhat better and this helps at real lo flow rates like idle and very light throttle. Bottom line is don't take out your stock injectors unless they have an issue! But when it comes time to replace them they are very expensive and then it may be nice to move to the more affordable modern injectors. These are not cheaper in quality, in fact they atomize fuel better but cost less because they are produced in huge volume. The injectors I'm considering for my upgrade package will be Ford 24lb injectors most likely bosch # 0-280-155-715 because they are readily available and I have the full spec sheets from Bosch. I am running these at the moment in my 84 Carrera with my MAF conversion and they run well, still testing though.
Quote:
Originally Posted by scarceller View Post
The new 715 injectors would not really help MPG nor reduce carbon compared to new factory injectors. But the fact that the 715 injectors are factory new could certainly help when compared to old tired factory injectors.

However, the new chip that would support the new injectors will likely improve MPG because it's specifically tuned PartThrottle ignition table is somewhat better tuned than the factory table. Any MPG improvement would come from the better tuned PT ignition table and most likely not from the injectors alone.
Quote:
Originally Posted by scarceller View Post
The 0-280-155-715 will NOT just drop in and work. It's funny you found these as I am currently testing these exact injectors in my 3.2L but they flow more fuel than the stock injectors and because they are also hi-impedance injectors they require more injector offset/on time. I had to change several parameters in the DME program to accommodate these injectors. I'm still testing them and so far they work great but they will require a custom chip to use them. Don't bother trying to install these in a stock DME, car will start and run but will run very rich. The only drop in replacements have to be lo-impedance injectors so the injector offset/on times match.
Well.....I found some info on the 715's I got today and the info comes from non-other than scarceller himself. What was your final assessment? Are you still using them?

I've got a very custom chip so I'm hoping they are as wild an improvement as my 784's have been... I can't imagine anything could be better than the 784's, but I can dream.
Old 07-10-2017, 04:43 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #303 (permalink)
Registered
 
scarceller's Avatar
 
Join Date: Oct 2006
Location: Southern MA
Posts: 3,690
Garage
The 715 injectors are hi-impedance and have very different offset (dead) times. They will work but not correctly with the stock chip or any other aftermarket chip. I do have a solution that works properly with brand new Bosch OEM 759 (30 lb) injectors.

You certainly are free to try using the 715s but they will run lean at very low pulse widths because they need about 2X the offset (on time) than the original injectors. You may be able to hit the mixture setting at idle by adjusting the CO screw on the AFM but then you'll run rich at the higher loads.
__________________
Sal
1984 911 Carrera Cab M491 (Factory Wide Body)
1975 911S Targa (SOLD)
1964 356SC (SOLD)
1987 Ford Mustang LX 5.0 Convertible
Old 07-11-2017, 06:11 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #304 (permalink)
Registered
 
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,725
Quote:
Originally Posted by scarceller View Post
You certainly are free to try using the 715s but they will run lean at very low pulse widths because they need about 2X the offset (on time) than the original injectors. You may be able to hit the mixture setting at idle by adjusting the CO screw on the AFM but then you'll run rich at the higher loads.
You might also consider using Siemens injectors that are described as having:

"Excellent response characteristics
Robust Design
High Impedance
Low Impedance performance characteristics with High Impedance Compatibility "

60lb/h Siemens Deka High Impedance (Long Style) with EV1 Connector – FI114961 (60mm) | Muscle Motors | Siemens Deka Distributor

http://www.siemensdeka.com/wp-content/uploads/2012/08/FI114961-2.jpg

Cheers,
Joe

Last edited by stlrj; 07-16-2017 at 11:58 AM..
Old 07-16-2017, 11:55 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #305 (permalink)
Registered
 
scarceller's Avatar
 
Join Date: Oct 2006
Location: Southern MA
Posts: 3,690
Garage
Just thought I'd share that currently someone has 364 injectors on ebay listed as new old stock!
https://www.ebay.com/itm/NEW-OUT-OF-BOX-Bosch-0280150364-Fuel-Injector/184011419315

They are asking $20 for each, this is a bargain price if they are really new old stock. These are drop in replacements for the 3.2L factory 158 injectors, the 364 differs only in that they have metal tip instead of plastic.

Enjoy!
__________________
Sal
1984 911 Carrera Cab M491 (Factory Wide Body)
1975 911S Targa (SOLD)
1964 356SC (SOLD)
1987 Ford Mustang LX 5.0 Convertible
Old 01-09-2020, 05:59 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #306 (permalink)
 
Registered
 
4flyboy's Avatar
 
Join Date: Jul 2006
Location: Delray Beach/So. Cal
Posts: 2,815
Garage
Hey Sal,

Don't mean to be impertinent but I know squat about fuel injectors. Are you confident that these are drop in replacement for 84 3.2 Carrera?

Appreciate the tip, thanks.

Scott
__________________
Scott

"Houston, Tranquility Base here, the Eagle has landed"

Silver 1984 M491 Sunroof Coupe
Old 01-09-2020, 02:11 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #307 (permalink)
Registered
 
scarceller's Avatar
 
Join Date: Oct 2006
Location: Southern MA
Posts: 3,690
Garage
The 364 injectors work well as replacements for the 158 stock injector. Look through this thread for details. I even compared them with a Wide Band O2 gauge at idle, part throttle and WOT. I do suggest you always reset base mixture as you'd do even if replacing the 158s with new 158s.

These older single pittle lo-impedance injectors are very difficult to find new these days.

Quote:
Originally Posted by 4flyboy View Post
Hey Sal,

Don't mean to be impertinent but I know squat about fuel injectors. Are you confident that these are drop in replacement for 84 3.2 Carrera?

Appreciate the tip, thanks.

Scott
__________________
Sal
1984 911 Carrera Cab M491 (Factory Wide Body)
1975 911S Targa (SOLD)
1964 356SC (SOLD)
1987 Ford Mustang LX 5.0 Convertible
Old 01-10-2020, 06:43 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #308 (permalink)
Mo money = mo parts
 
Join Date: Jul 2003
Location: Pittsburgh, PA
Posts: 1,184
Garage
It appears that they only have 1 since you can't alter the quantity. I did not message the seller to confirm. Also, if you look at the photo the part number on the actual injector is 0280150362. The title of the auction says 364, but the photo shows 362.
__________________
Greg

86 Coupe (stock - pretty much like Butzi designed it)
65 Ducati Monza 250 & 66 Monza Junior (project)
"if you are lucky enough to own a Porsche, you are lucky enough"
Old 01-13-2020, 09:10 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #309 (permalink)
Registered
 
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,725
Quote:
Originally Posted by scarceller View Post
3.2L Motronic Injectors are Low Impedance

If I have a choice, why would I choose a low-Z or high-Z injector?

"Until recently, most performance injectors with higher flow rates (900cc/min or more) would likely have been low impedance injectors. This is because in the older (fat body style) low impedance injectors (’80s and ’90s designs) had faster opening response times and generated less heat when they were being operated with proper peak and hold injector signals. This meant that at higher flow rates and lengthier duty cycles low impedance injectors would outperform their high impedance counterparts. Since so many of the performance injectors back then were low impedance injectors and they were actually better than their high-z equivalents, the common belief which still lingers today (though it is no longer correct) is that low-z injectors are the best for your high performance vehicle.

Today’s high impedance injectors, however, are able to outperform those older low impedance injectors at larger flow rates due to their newer designs, tighter manufacturing tolerances and much lighter moving parts(examples are our 900cc, 1100cc and 2150cc/min injectors). A valve and spring assembly from a current high-z injector may weigh less than 1/3rd of the assembly from an older injector.

Thanks to this newer technology the current high-z injectors are more linear throughout their pulse range; they are able to repeat shorter pulse widths consistently which means they can provide excellent part throttle and idle characteristics, and operate at higher maximum operating pressures.

These facts make choosing one of the new high-z injectors we offer a no-brainer if your ECU and fuel system setup allows you the choice, and the budget will stretch to the slightly higher average cost."

https://fuelinjectorclinic.com/index.php?_route_=faqs/#3
Old 01-15-2020, 07:56 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #310 (permalink)
Registered
 
scarceller's Avatar
 
Join Date: Oct 2006
Location: Southern MA
Posts: 3,690
Garage
You can not just put a hi-imp injector in these 84-89 3.2L engines, the injector offset times are 2 to 3 times greater for the hi-imp injector than the lo-imp stock inj. You can use hi-imp injectors in the 3.2L but only with a custom chip that has the proper injector offset times. I know this because I have used Bosch 30lb hi-imp injectors in these motors with a special chip I created.

The DME has no issue firing hi-imp injectors but it must be properly programed for the given injector spec.
__________________
Sal
1984 911 Carrera Cab M491 (Factory Wide Body)
1975 911S Targa (SOLD)
1964 356SC (SOLD)
1987 Ford Mustang LX 5.0 Convertible
Old 01-15-2020, 08:07 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #311 (permalink)
Registered
 
Join Date: Sep 2010
Posts: 2,831
Garage
All I know is I bought inexpensive units from auto zone. They told me they were drop in for my car. When I had my top end done my shop said they were absolutely wrong and replaced them with Bosch injectors. I trust my shop.
Old 01-15-2020, 08:08 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #312 (permalink)
Registered
 
scarceller's Avatar
 
Join Date: Oct 2006
Location: Southern MA
Posts: 3,690
Garage
You did the right thing! You can not just drop any injector into these motors. Your shop made the correct decision. Different injectors can be used but it's not easily done and requires custom chip work.

Quote:
Originally Posted by Nick Triesch View Post
All I know is I bought inexpensive units from auto zone. They told me they were drop in for my car. When I had my top end done my shop said they were absolutely wrong and replaced them with Bosch injectors. I trust my shop.
__________________
Sal
1984 911 Carrera Cab M491 (Factory Wide Body)
1975 911S Targa (SOLD)
1964 356SC (SOLD)
1987 Ford Mustang LX 5.0 Convertible
Old 01-15-2020, 08:26 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #313 (permalink)
Registered
 
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,725
Quote:
Originally Posted by scarceller View Post
You can not just put a hi-imp injector in these 84-89 3.2L engines, the injector offset times are 2 to 3 times greater for the hi-imp injector than the lo-imp stock inj. You can use hi-imp injectors in the 3.2L but only with a custom chip that has the proper injector offset times. I know this because I have used Bosch 30lb hi-imp injectors in these motors with a special chip I created.

The DME has no issue firing hi-imp injectors but it must be properly programed for the given injector spec.

But Sal, I've been on hi-imp injectors for years and they perform better than the originals on a stock chip. Just goes to show that there are some experts out there that seem to have more experience than we do. Meanwhile, if and when find the downside I will certainly let you know. Aside from chips and injectors, the real performance problem with the 3.2 is the lack of expertise in air flow meter adjustments and there are just as many ways to make it worse as there are there are to make it better. Knowing how to properly set it up far out weighs any benefits from injector or chip mods if AFM outputs garbage in then what you can expect is nothing more. This is why not all cars will benefit equally from a chip or injector mods.


Cheers,

Joe

Last edited by stlrj; 01-15-2020 at 09:31 AM..
Old 01-15-2020, 09:04 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #314 (permalink)
Registered
 
ischmitz's Avatar
 
Join Date: May 2002
Location: Santa Barbara, CA
Posts: 4,633
Garage
Send a message via Skype™ to ischmitz
Just to re-cap. When the 3.2 DME was developed there were several challenges/restrictions in terms of what electronics was capable off and what injectors were available at the time.

Injectors needed to be low-impedance to achieve the required performance characteristics (short opening times, high dynamic range). So a high-performance injector was low-impedance for speed. The 3.2 fires all six of them at the same time and this compounded the problem: Each injector is around 2.6 Ohm but the net impedance is well below 1 Ohm with all six wired in parallel to the single injector output. That required really huge currents to work.

On the electronic side the technology en-vogue was a BJT transistor. Versions that could deliver enough current had low hFE gains. This resulted in poor conductance and big losses (heat) in the transistor. Because of that a Darlington configuration had to be used. Even then a peak&hold scheme was required with a sophisticated PWM driver. It shocks the injectors open for less than a millisecond and then uses current feedback to maintain a lower holding current via PWM. Additionally the energy coming back from the injectors had to be dealt with by more circuitry. This made the drive circuit very complex by modern standards and required propriety Bosch parts that are NLA.

Fast-forward to today: high-impedance injectors are much faster and perform comparable to their low-impedance counterparts. In addition modern low-side drivers with MOSFET technology can deliver extreme currents with very little losses just like a switch. This makes design much easier. Bosch went to sequential injection in the 964 where each injector has its own channel.

But as others said the old 3.2 DME can drive high-impedance injectors without problems. It's just important that the flow and characteristics are matched or differences are accounted for in the programming of the maps in the DME.

Ingo
__________________
'74 Targa 3.6 (not stock ) - '01 C4 (almost stock) - '00 ML430 (stock)

I repair/rebuild Bosch CDI Boxes and Porsche Motronic DMEs
Porsche "Hammer" or Porsche PST2 - I can help!!
How about a NoBadDays DualChip for 964 or '95 993
Old 01-15-2020, 10:16 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #315 (permalink)
Registered
 
Join Date: Sep 2010
Posts: 2,831
Garage
Or you can just install Bosch and drive your car and it runs perfect.
Old 01-15-2020, 11:41 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #316 (permalink)
Registered
 
scarceller's Avatar
 
Join Date: Oct 2006
Location: Southern MA
Posts: 3,690
Garage
Only problem is you can no longer purchase/find new bosch injectors for the 84-89 3.2L the stock injector is Bosch part # 0.280.150.158 and they are no longer available.

Quote:
Originally Posted by Nick Triesch View Post
Or you can just install Bosch and drive your car and it runs perfect.
__________________
Sal
1984 911 Carrera Cab M491 (Factory Wide Body)
1975 911S Targa (SOLD)
1964 356SC (SOLD)
1987 Ford Mustang LX 5.0 Convertible
Old 01-15-2020, 12:01 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #317 (permalink)
Registered
 
Join Date: Sep 2010
Posts: 2,831
Garage
My shop just installed Bosch for about $150 each. Maybe they had old stock.
Old 01-15-2020, 01:19 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #318 (permalink)
 
Author of "101 Projects"
 
Wayne 962's Avatar
So, I've been doing a search for alternative part numbers for injectors, and this page came up:

https://www.********.com/en/moreinfo.php?pk=533438&jsn=262



This would seem to imply that this AC DELCO injector (probably made by BOSCH for them) is similar / interchangeable with the following?

ACDELCO 2172269

Alternate/OEM Part Number(s): 0280150201, 0280150352, 0280150360, 0280150364, 0280150634, 13641273272, 19110469

The 360 and 364 numbers lend credence to the theory?

Here's another discussion where someone points out the same thing:

https://www.impactbumpers.com/forum/index.php?/topic/30960-32-carrera-fuel-injector-alternative/

I wonder if anyone has done any further research on this? Injectors are available from Porsche for about $350 each (and I'm not sure if they are rebuilt or new!), and these are $40 each it would seem and still available?

-Wayne
Old 05-18-2020, 12:05 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #319 (permalink)
Registered
 
Join Date: Oct 2010
Location: Connecticut
Posts: 2,087
Garage
Pelican is now selling a no-name injector first the 944/924S, less than $40 each (maybe also for 3.2 Motronic’s too? I haven’t looked).

EDIT: whoops, what PP is offering are reman parts.

Wayne, I’m assuming that a business like PP/ECS et al gets offered such items from Chinese vendors with some frequency? I don’t know how you figure out if the stuff is any good?

Best, John

Old 05-18-2020, 12:29 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #320 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 11:56 AM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2020 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.