Step by Step; 1700 carb to EFI (future to 2054)

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larsje
Posts: 18
Joined: Fri May 15, 2009 3:06 pm

Step by Step; 1700 carb to EFI (future to 2054)

Post by larsje » Thu Jun 21, 2018 7:41 am

Currently building and planning some stuff for my '72 Baywindow engine;

First up, I will convert the tired 1700cc to EFI.
This is my first venture into the EFI/EFI tuning, so what better than use and abuse a tired 1700.

In general, this is what I am planning:
- should not look like a racing engine
- stock cooling
- 2L FI intake plenum
- intake runners from 914 FI engine
- choose the budget-friendly options where possible
- do as much as possible at home / by myself

larsje
Posts: 18
Joined: Fri May 15, 2009 3:06 pm

Re: Step by Step; 1700 carb to EFI (future to 2054)

Post by larsje » Thu Jun 21, 2018 8:17 am

As I am at home now on parental leave for my December born daughter, I had a lot of time to plan/do some stuff while she was sleeping during the days.

My baywindow:
Image
Last edited by larsje on Thu Jun 21, 2018 8:43 am, edited 1 time in total.

larsje
Posts: 18
Joined: Fri May 15, 2009 3:06 pm

Re: Step by Step; 1700 carb to EFI (future to 2054)

Post by larsje » Thu Jun 21, 2018 8:19 am

I modified a TB from a FI engine

- 52 mm throttle plate (from a DBW throttle body from a 2014 VW Golf)
- ball bearings
- custom shaft
- TPS adapter plate
- Bosch TPS

Image

larsje
Posts: 18
Joined: Fri May 15, 2009 3:06 pm

Re: Step by Step; 1700 carb to EFI (future to 2054)

Post by larsje » Thu Jun 21, 2018 8:45 am

Custom made exhaust

took an old Ahnendorp header (mild steel, all rusted up) and fitted a CSP stainless damper box.
Also fitted EGO sensor.
Currently running innovate, but will be run by ECU in the future

Image

larsje
Posts: 18
Joined: Fri May 15, 2009 3:06 pm

Step by Step; 1700 carb to EFI (future to 2054)

Post by larsje » Thu Jun 21, 2018 11:20 am

For the Engine management I will use a ECUmaster EMU Classic ECU.

I chose this ECU for several reasons;
- cost is about the same as a pre-built Megasquirt
- built in EGO sensor controller
- support by dealer , manufacturer and community
A lot of features I do not need (for now) but are cool to play with in the future (e.g. 2x EGT sensor controller built in)

Because it is a conversion from carburetors to EFI, i need to make a new wiring harness, so I made a layout in PowerPoint.
I will use a pigtail wiring harness from ECUmaster to begin with.
IAC will probably be skipped

Image

Trigger wheel and sensor i got from Germany, and will fit between the case and cooling fan.
Not sure about the sensor tough, as it does not look like the typical TDC sensor. It has 2 wires so must be a VR sensor.
Anyone experienced with this type of sensor?

Image

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raygreenwood
Posts: 11805
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Re: Step by Step; 1700 carb to EFI (future to 2054)

Post by raygreenwood » Sat Jun 23, 2018 12:45 pm

You should dump the 2.0L 914 plenum. It has worse flow than ANY of the side entrance TB's ranging from 1.7L 411/412/914 to 1.8 and 2.0L bus.
The 1.7L of course is too small for a 2056...but a 1.8L 412, 914 or bus plenum will work fine. A 2.0L bus plenum will work very well.

The problem with the 2.0L 914 set up is that the incoming air has to make many 90* turns per second in four different directions to hit the runners...and has no appreciable distance between TB and the floor of the plenum. It takes a distance of between 5X and 7X (or more) of the diameter of the runner...behind the TB plate...to dissipate the nasty plume of turbulence created by the throttle plate. You do not have that room on the 914 2.0L plenum....and you get another nasty knot of turbulence due to that plume of TB turbulence having to make 90* turns just inside as it exits the plenum.

The 1.7L, 1.8L and 2.0L bus plenums are a MUCH better design. They enter offset and bounce the TB plume off the curve section just opposite the TB which re-centers the plume and straightens it out a bit. And...yes....I have actually visually seen this back in the late 90's using smoke testing with a tuboscope through the cold start valve hole. It was amazing.....wish I had video. Keep meaning to reproduce this at some point.

The TB in your picture should bolt right up to any of those. You simply need to take a muffler expander and work the inlet hole slightly to match teh larger TB.

If you scroll down in this thread...you can see the plenum pictures with the expanded TB opening near the very end.
https://www.thesamba.com/vw/forum/viewt ... p?t=683230

Ray

larsje
Posts: 18
Joined: Fri May 15, 2009 3:06 pm

Re: Step by Step; 1700 carb to EFI (future to 2054)

Post by larsje » Sat Jun 23, 2018 12:53 pm

raygreenwood wrote:You should dump the 2.0L 914 plenum. It has worse flow than ANY of the side entrance TB's ranging from 1.7L 411/412/914 to 1.8 and 2.0L bus.
The 1.7L of course is too small for a 2056...but a 1.8L 412, 914 or bus plenum will work fine. A 2.0L bus plenum will work very well.

The problem with the 2.0L 914 set up is that the incoming air has to make many 90* turns per second in four different directions to hit the runners...and has no appreciable distance between TB and the floor of the plenum. It takes a distance of between 5X and 7X (or more) of the diameter of the runner...behind the TB plate...to dissipate the nasty plume of turbulence created by the throttle plate. You do not have that room on the 914 2.0L plenum....and you get another nasty knot of turbulence due to that plume of TB turbulence having to make 90* turns just inside as it exits the plenum.

The 1.7L, 1.8L and 2.0L bus plenums are a MUCH better design. They enter offset and bounce the TB plume off the curve section just opposite the TB which re-centers the plume and straightens it out a bit. And...yes....I have actually visually seen this back in the late 90's using smoke testing with a tuboscope through the cold start valve hole. It was amazing.....wish I had video. Keep meaning to reproduce this at some point.

The TB in your picture should bolt right up to any of those. You simply need to take a muffler expander and work the inlet hole slightly to match teh larger TB.

If you scroll down in this thread...you can see the plenum pictures with the expanded TB opening near the very end.
https://www.thesamba.com/vw/forum/viewt ... p?t=683230

Ray
Thats why i have a 2L (bus) plenum, but are going to use the 914 runners (bigger pipe diameter, no step in the pipe after the connection to the plenum)

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raygreenwood
Posts: 11805
Joined: Wed Jan 22, 2003 3:01 am

Re: Step by Step; 1700 carb to EFI (future to 2054)

Post by raygreenwood » Sun Jun 24, 2018 5:54 pm

Oh!...cool! Somehow I missed that part. That will be a nice set up!
Ray

larsje
Posts: 18
Joined: Fri May 15, 2009 3:06 pm

Re: Step by Step; 1700 carb to EFI (future to 2054)

Post by larsje » Sun Jul 22, 2018 3:58 pm

Small update (not much time available right now);
Removed the EGR (Exhaust Gas Recirculation) piping in the plenum and closed the EGR connection on the plenum. And a nice coat of black.

Image

Next steps; fuel system
Starting from the tank;
It will get a POR 15 treatment and I will braze a stainless AN 8 fitting to it (just before coating, but after cleaning/ rust removal)

From there i will go to the fuel pump with a “push on” style hose, then to the fuel filter.

Need to make a bracket for pump/ filter.

Image
Image

After that I need to modify the runners; shorten (the plenum is wider than the plenum to which the runners originally belong to)
And drill for 14 mm modern injector seats.
Image

Still need to play with the angle on the drill press, will be drilling from 10 mm originally to the required seat, last bit will be done with a reamer to get the required surface quality.

[IMG]//uploads.tapatalk-cdn.com/201807 ... 487c8e.png[/IMG]

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