firemn131

Installing the injectors but I am unsure as to the correct size of the pintle caps.

I have blue and yellow caps.
Blue are 7.54 mm
Yellow are 6.6 mm.

I found an old green one (5.24 mm) in the box of parts that came with the car.

I have reseal kits from 944 online, but remember hearing that the caps were the wrong size.

Does anyone know the stock size and if you have used either of the 2 mentioned above with no problems.
When I got the car it did not have the injector caps.

Any help is greatly appreciated

chudson

Here's the best I can do.

These are fresh from cleaning at Marren Fuel Injection 203 267 3835. The owner there is very helpful and would likely answer the question for you. Obviously, mine are green.

Cliff

Jfrahm

That picture above looks the same as my stock 1992 injectors, 0-280-155-010. The caps are short and different from more typical caps. External dimensions are:
12mm at the "brim:
9.15mm diameter
5.5mm tall

This is more-or-less the same as an S2 injector 0-280-450-611 cap except the S2 cap is 1mm taller (6.5mm)

The 1995 Dodge Ram 2500 V10 might use the same pintle cap, otherwise it appears to be pretty uncommon. 5-0 motorsport might be able to get them, they helped me with the 928S4 injector O rings which are an oddball size.

For what it's worth I switched my 1992 968 to Bosch 0280155831, 0-280-155-831, listed as 32 lb/hr at the standard measurement. These are IMO a better updated design. No problems in a few years. Very cheap on Ebay and usually in a set with extras. Under $30 for a used set of 5 right now or more for serviced ones.

Backflusing and cleaning, parts replacement is easy on the newer style. The -830 should also work fine, they flow a teense more but if the stockers were sized for E0 gas and we run E10 now they are real close to the same in terms of potential energy per squirt. They are also common and cheap.

Either should be no problem for the fuel trim to work with.

-Joel.

chudson

Joel - I'm curious.

Injector failure is rare. Why do you prefer the 831?

Jfrahm

Lots of reasons. I figured my stockers could stand to be cleaned at 160K miles and IMO there is no point in putting the "potbelly stove" injectors back in when you can get a newer design with a better spray pattern and no leak path in the body (no body seam) for a few bucks and clean those. The updated injectors are also somewhat quieter and that's nice, the racket from the injectors might hide other more important noises. Also no pintle caps to fall off or crack apart.

This all started on the 928, 928 folks found that the "4 hole" injectors from a Crown Vic or whatever worked well on the 928 and I put a set of those in my 928 blower car while I had the blower off replacing the timing belt and sorting other stuff out. I did not have a set of stock 928S4 injectors laying around so I needed to buy some and the 4 hole injectors are actually cheaper than the old potbellies with the peeling paint and whatnot.

The spray pattern might be better, who knows? The car ran great before and it runs great after.

You do want to make damn sure the injectors are retained to the rail, the stock clips are good or they can be safety wired to the rail. I have not fussed with the 968 rail to see if an unclipped injector can pop loose but it's not worth the risk. On a 928 it is possible for an injector to pop out of the rail and fuel to spray everywhere.

If you have lost the clips BMW clips are cheap off Amazon or wherever. Make sure they are not bent and are seated properly.

Tip: You can often get a whole fuel rail and injector set for less than the cost of loose injectors, there is an XC90 rail on the 'bay right now for $40 with 5 injectors.

-Joel.

por4ever

Sorry to resurrect an old thread but I just went through this on my car. I ended up going through 3 suppliers. First was the kit sold in parts stores under various names. The one I got was in a BWD box. Second was the kit sold by Pelican which appears to be the Rennbay part. Lastly I went AUS Injection in Tempe, AZ. Following are the dimensions I measured for each cap, in mm.
OEM: H 5.3 ID 7.4 OD 9
BWD 7.6 ID 7.5 OD 9.6
Pelican (Rennbay) H 7.8 ID 7.6 OD 9.5
AUS Injector (P/N Black 130) H 5.6 ID ?? Snug fit with no movement OD 9.2

My concern was the taller cap would interfere with the spray pattern. My last alternative would have been to drill out the cap.



OEM, BWD, Pelican


Pelican, AUS Injector, OEM


BWD, OEM, Pelican