Rick in NYC

I am considering upgrading my 23 year old stock fuel injectors to the new Bosch Type 3 style. They seem to have a fine mist spray, which may help at start ups. Here is a link to a Youtube video of them in action.


Has anyone converted to them?

Thanks for your advice.

1990 944S2

Van

Wow, very informative.

Lemming

Yep, and here is the result.

Van

Tim, so that shows that there is little, if any, measurable gain for switching to the new injectors.

Lemming

Correct. We got the car dialed in after a few runs on the old injectors (run #2). I then changed injectors, nothing else, and we ran it again (Run 1, 18 minutes after run 2). As you can see no difference. There are a few threads on the 968 forums about switching a few years ago and this is the result of me trying it.

catamax944

So no power gains but would the better atomization affect fuel economy ?

Van

Not if the flow volume is the same.

My guess is with the air rushing into the cylinders, it's turbulent enough to get the fuel spread around.

Also remember, our injectors are batch fired. When they fire against the closed intake valve, fine atomization or not, it's going to pool up until the valve opens and the air sucks it in.

dirtyTurbo

Very interesting. Just today actually I switched my injectors to some I found on a ford motor. I don't know if they're type 3 or not but they have 4 small pinholes. I made a video too, hopefully I'll be able to upload it later

Rick in NYC

Thank you Tim for your chart and everyone's good advice. There is no easy way to get more H.P. out of these motors!
Since there's snow, I am looking for a winter project. Once a year I put in a bottle of Techron and my motor with 144,000 miles runs fine. Are the Fuel Injector rebuilding services a waste of money?

Fara

The injector cleaning services do a great job at maintaining the horsepower in your engine. It won't ADD any horsepower, but it'll reduce the chance of a Fiat 500's worth of power escaping.

F40LM

I have never used a service but have always heard great things about Witchhunter.

You can also remove and rebuild them yourself. There are you tube vids on making your own cleaner and using a small ultrasonic box. I cleaned and rebuilt mine for a total of $50. And now that I have the stuff it will just cost me the ring set in the future so maybe $20 to rebuild four. About to remove the injectors from a friends Honda to clean and rebuild them for him.