78 Fuel injection for 75 (1.7L) Bus?

[hercdriver]

I was wandering. I've got a 75 Westy that has a CB engine (1.7) with a weber carburetor. I'd like to go back to fuel injection. I understand 75 was an odd year that had some issues. I'm also seeing many more complete F/I systems being sold for the later years.

Is it possible to set up the 1.7 for F/I with the F/I parts off of a 78? Any thoughts would be appreciated.

Here's what I'm looking at now.

http://www.thesamba.com/vw/classifieds/ ... ?id=842727

[Bleyseng]

I think you should be able too, might have to use the injectors off a 1.8L 0-280-150-112 vs the 2.0L 0-280-150-114 ones. I am a sure you will have to adjust the AFR but thats fairly easy.

[dtrumbo]

Make sure that comes with the ECU. I see the connector for it in the picture, but I don't see the unit itself. That would be like putting a jig-saw puzzle together and not having the last piece that's bigger than all the rest and right in the middle of the picture.

[hercdriver]

Make sure that comes with the ECU.

I've emailed the seller making the sale contingent on the inclusion of the ECU. It seams like a fair price. If I can't use it, I hope to sell it without taking a beating.

My assumption through all of this is that the engine itself does not have any specific mods for fuel injection (heads don't need any machine work?).

[Amskeptic]

Make sure that comes with the ECU.

I've emailed the seller making the sale contingent on the inclusion of the ECU. It seams like a fair price. If I can't use it, I hope to sell it without taking a beating.

My assumption through all of this is that the engine itself does not have any specific mods for fuel injection (heads don't need any machine work?).

The left cylinder head may require a tap for the cylinder head temperature sensor. The 1975 FI system was calibrated for the 1.8 displacement, so you are close enough with a 1.7. Check your valve sizes. IIRC, you want the smaller intake valves of the 1.7 over any big 1.8 42mm intakes that were supplied with the dual carb 1.8 engines. VW dropped the valve size when they switched to FI to keep intake air velocity up.
If you have bona fida 1.7 heads, you should be OK.
Colin

[hercdriver]

The left cylinder head may require a tap for the cylinder head temperature sensor. The 1975 FI system was calibrated for the 1.8 displacement, so you are close enough with a 1.7. Check your valve sizes. IIRC, you want the smaller intake valves of the 1.7 over any big 1.8 42mm intakes that were supplied with the dual carb 1.8 engines. VW dropped the valve size when they switched to FI to keep intake air velocity up.
If you have bona fida 1.7 heads, you should be OK.
Colin

Colin,
The bus is a 75'. The engine I have now is a 1.7 "CB" (if I'm to believe the fan shroud) and the F/I setup is coming off of a 78' 2.0 liter.

Can this work? Or am I trying too hard with Frankenstein?
How can you tell if they are in fact 1.7 heads? (Please don't say you have to pull them.)

Dave

[Amskeptic]

F/I setup is coming off of a 78' 2.0 liter.
Can this work?
How can you tell if they are in fact 1.7 heads?
Dave

I think it will work fine. You will need to adjust the AFM.
1.7 heads have certain tell-tales like air injection ports (if '73) and 13mm adjuster screws. Because people have had plenty of time to monkey with these cars, you never know what you are actually getting until you measure dimensions yourself.
Colin

[hercdriver]

Yippeeee! =D>

I feel like I just went two steps forward this time! Lately it's been the other direction.

I'll post up some pics when the parts come in. It should be the whole lot (pump, ecu, injectors, etc).

[Bleyseng]

What exhaust system do you have? Using the early HE's and a extractor muffler set up will be a help. A free flowing exhaust over stock helps pull the heat out.
I think it will work fine...with whatever heads you have.

[dtrumbo]

Does your fuel tank have the inlet for the fuel return? You'll also need the fuel pressure regulator. Maybe your box o' fuel injection parts will have that too.

[chitwnvw]

Does your fuel tank have the inlet for the fuel return?

I was wondering about this too. Early '75s wouldn't have it, would they?

[dtrumbo]

I'd like to go back to fuel injection.

This implies it at one time had fuel injection which is a good thing. That said, there is no telling what the PO or their mechanic did to seal the return inlet.

[Gypsie]

JB weld anyone?....

[hercdriver]

This implies it at one time had fuel injection which is a good thing. That said, there is no telling what the PO or their mechanic did to seal the return inlet.

It's a 75. My understanding is that all 75's were F/I. Have I assumed incorrectly?

[dtrumbo]

It's a 75. My understanding is that all 75's were F/I. Have I assumed incorrectly?

That's my assumption as well, but regardless, the fuel tank in your bus will have to have the return inlet in order for your fuel injection to work. You should take a look under your bus and see what's what. Hopefully your fuel tank has both the outlet and inlet and that the currently unused inlet is blocked off in such a way as to allow you to resurrect it when it comes time to install the fuel injection.

This diagram is for a '76, but at least you'll get an idea of what the heck I'm blathering about. Courtesy of Scott Lyons (German Supply) via Richard Atwell (www.ratwell.com)