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VaccaRabite
I am retrofitting this thread to be my full on conversion thread, documenting my change from dual 40 Webers to MSII fuel injection.

Here is what I have so far, and what I need:
HAVE:
  • MSIIv3.52 pre-built box.
  • JimStim board for testing the MSII box
  • V3 main Board wire harness.

    Will soon have:
    Injection system off a 1.8 914, from which I will use
  • Throttle body
  • Intake Runners
  • Fuel Injectors (unless I find they don't flow enough fuel)
  • Fuel Rail
  • Fuel Pump (maybe - Joe may still need it for himself)

    Stuff I need:
  • TPS or MAF sensor
  • 4 wire O2 sensor
  • Bung welded into exhaust
  • Fuel Pump (Maybe, see above)
  • Other stuff I don't know about yet
The engine is a 2056, particulars as follows:
Built on 1.7 heads.
Jake's 9530 cam (carb cam similar to Web 494)
Mallory optical ignition
ACCEL (UltraCoil) coil.
SSI exchangers for exhaust.

My goals for this project are to have near stock intake noise volume, better cold starting - especially in cooler weather, negate the bad effects or Ethanol on carbs, teach myself something about fuel injection.

Since I already have a pretty good ignition system, I am not going to go after crank fired ignition at this time, but I am not ruling that out for the future.

Before I begin the conversion, I am going to pull the engine and do a little refreshing and cleaning, including:
  • Fixing an oil leak at the front of the engine
  • cleaning under all tins (not that I exect to find much, but its a good thing to do)
  • Fix some cooling tins issues that I have been living with for the past 2 years
  • Open up holes in the tins I welded shut so I can replace heater tubing and heat my cabin!
  • Check for battery acid leaks or rust appearance in the engine bay. Neutralize.
QUOTE
I am getting ready to start my conversion form carbs to EFI.

My goal is to use as much stock EQ as I can, but replace the sensors and such with modern, easy and cheaper to find stuff. Plus, since my car has a cam, the stock FI will not work.

My engine has 1.7 4 bolt heads.
1) are the 1.7 and 1.8 intake runners the same?
2) Is the intake runner inside diameter smaller then the 2.0 intake runner ID?
3) is the throttle body for the 1.8 smaller then the throttle body for the 2.0?

If the 1.8 TB is smaller then the 2.0, can the 2.0 TB be swapped in?

Are 1.8 injectors high or low impedance?

I am asking this as I will be able to get Joe's discarded 1.8 bits when he pulls his engine and starts going down the 2056 route.


Zach
underthetire
1.7 and 1.8 runners are not the same, 1.8 is slightly bigger, but won't match up to the 1.7 plenum. I have no 2.0 stuff to compare. The 1.8 runners will bolt up to your heads, that much I know. I always thought the 1.8 injectors were high, but several here have actually measured them, and found them low just like the rest.
Krieger
I pretty sure the stock throttle body bore for a 2.0 is 45mm.
McMark
Yup, none of the intake runners are the same or interchangeable with other plenums, although I have cut and reoriented intake runners. Specifically getting a set of 1.8 runners to match a 2.0 plenum.

All 914 injectors are low impedance. L-Jet uses a resistor pack to 'emulate' high impedance injectors. If you want to use stock injectors with MegaSquirt, you can get one of those resistor packs to do the same.

The 2.0 throttle body has a flat bottom, and the 1.7, 1.8 have taper/cone bottoms. You could look into the size of the bus 2.0 TB.
Valy
Since you want to use newer parts, L-Jet (1.8) is the way to go.
The air plumbing is not interchangeable. The J-tubes for 1.8 and 2.0 are the same diameter but different length. 1.7 are a bit smaller.

There are many cars fitted with L-Jet so you can rip parts from them.
Ont thing you should pay attention to is the Air flow sensor. Older L-jet (like the 914) have a potentiometer that has a linear relation to the air volume. Newer ones are not linear (to save manufacturing cost) ant the ECU compensates for linearity.
VaccaRabite
If the 1.8 and 2.0 intake runners are the same ID, are the throttle bodies also the same ID? Will I be starving my 2056 using the 1.8 throttle body?

Zach
7275914911
In the research I did it looked like the Bus plenum/TB worked/flowed better in a 2056 setup w/L-jet. IIRC that comes from discussions on Jakes site and Shoptalkforum...
FourBlades

If you are going to megasquirt, is there a plenum and set of sensors from a
common, modern car with a MAF, like a newer VW that would work?

Not using ITBs would allow you to use a lot of stuff from a more recent car.

John
r_towle
QUOTE(Vacca Rabite @ Oct 12 2011, 08:21 AM) *

If the 1.8 and 2.0 intake runners are the same ID, are the throttle bodies also the same ID? Will I be starving my 2056 using the 1.8 throttle body?

Zach

the ljet system can run a 2.4 liter motor.
You obviously will need to tune the A/F map that you use, but the throttle body should work.
You will need a different throttle position sensor for the aftermarket EFI...the ljet one is an on/off switch for Idel and WOT only...

I believe the Ford focus or fiesta one fits and works, and it has the additional curcuits for you.

Rich
edwin
what carbs do you have now? why not use them and weld in injector bungs to the manifolds?
VaccaRabite
My primary goal is to kill the roar of running dual carbs. Get to a point where I don't need earplugs to go on a longer drive.

All the other benefits of EFI come second to this sime creature comfort. Otherwise I'd just keep the carbs.

Zach
scotty b
How about getting a TPI setup from a Chevy V8 and cutting it down to 4 cylinders rolleyes.gif poke.gif poke.gif poke.gif poke.gif
VaccaRabite
QUOTE(scotty b @ Oct 12 2011, 08:06 AM) *

How about getting a TPI setup from a Chevy V8 and cutting it down to 4 cylinders rolleyes.gif poke.gif poke.gif poke.gif poke.gif

What's this? The pot calling the kettle black?
rolleyes.gif poke.giflaugh.gif
Zach
r_towle
QUOTE(Vacca Rabite @ Oct 12 2011, 09:02 AM) *

My primary goal is to kill the roar of running dual carbs. Get to a point where I don't need earplugs to go on a longer drive.

All the other benefits of EFI come second to this sime creature comfort. Otherwise I'd just keep the carbs.

Zach

On the cheap....
look at this setup.
then think about doing it with two turbo covers and a type1 aircleaner box...
The filter is easy to get over time.
The covers can be had at CB performance
Hoses can get gotten lots of places.

You would have a nice quiet setup for short money.

http://www.csp-shop.com/cgi-bin/cshop2/fro...sort=0&all=

Rich
Dave_Darling
You can probably build an air-box for a lot less than that. Heck, just build it around your current air cleaners! Dyna-mat it (and make a long-ish intake snorkel pointing somewhere back away from you) and it should absorb a lot of the sound.

--DD
FourBlades
I finished building this same thing recently in the quest for quiet plus better low
end response. I need to post some pictures...

I tried it with and without dynamat on the runners and stuff and found it made
little difference.

I welded up the carb tops and made a dual 3 inch / one 4 inch center plenum then
added a $25 cone air filter. Think I spent $60 total on it.

It feels a lot quieter but my sound meter does not show much improvement DB wise.

I'll post pictures when I get home.

John
VaccaRabite
There are a lot of other advantages of EFI, especially for cars that sit for long periods of time like mine. Both my 914 and the v8 in my jeep are going EFI though it would probably be easier just to do the carb.

Zach
jsayre914
cant you just redrill the intake flanges and bolt the whole shabang on there? Sound like it can handle your engine with a bit of adjustment.

idea.gif
dlee6204
QUOTE
I finished building this same thing recently in the quest for quiet plus better low
end response. I need to post some pictures...

I tried it with and without dynamat on the runners and stuff and found it made
little difference.

I welded up the carb tops and made a dual 3 inch / one 4 inch center plenum then
added a $25 cone air filter. Think I spent $60 total on it.

It feels a lot quieter but my sound meter does not show much improvement DB wise.

I'll post pictures when I get home.

John


popcorn[1].gif Please do!
76-914
Hey Zack, Will you be our "FI Poster Boy" when the next great "Carbs vs. FI" debate comes around, again? happy11.gif
TargaToy
Zach, I'm glad you're asking this stuff. I drive the 1.7 but have a 1.8 waiting in the wings for a 2056 build up. Was wondering the same thing about the 1.8 runners being larger. They "seem" larger but when I threw my caliper on them, I got mixed measurements (mostly because I can only get on the bends on the runners in the car).

Still batting around L-Jet vs MS so research and learn away while I piggy-back on your findings!!!
FourBlades
I apologize if this is a hijack. I would like EFI for a lot of reasons as well but I
thought I would see in a quick and dirty way how much the carbs could be
quieted down.

Click to view attachment

The carb tops and plenum are just welded up exhaust pipe and 20 gauge sheet
metal. I put eastwoodmat around the carb tops. The tubing, couplers, and cone
filter are cheap FLAPS parts.

Click to view attachment

I need to do some more tests but my initial results are 88 db with itgs at 900 rpm
and 82 db at 760 rpm with my cheesy intake system. I was getting 104 db at
2600 rpm with itgs and never took a good reading with the new system at that
rpm. I'll get on that.

Now I can hear the exhaust a little but also a lot of general air cooled noise that
is not intake related.

This seems to help low end throttle response but obviously would be restrictive
past a certain rpm.

John
VaccaRabite
QUOTE(jsayre914 @ Oct 12 2011, 05:52 PM) *

cant you just redrill the intake flanges and bolt the whole shabang on there? Sound like it can handle your engine with a bit of adjustment.

The 1.8 stuff should bolt right up to my car. No redrilling needed. I'll be able to many of the stock parts but want to use a MS brain - as much to learn it as anything else. The bolt pattern for the intake runners at the head is the same for 1.7 and 1.8.

Since the TB and runners are the same as the 2.0 units, there will need to be no cobbling together.

QUOTE(FourBlades @ Oct 12 2011, 05:52 PM) *

I apologize if this is a hijack. I would like EFI for a lot of reasons as well but I
thought I would see in a quick and dirty way how much the carbs could be
quieted down.


Hey there my thread pirate. You should start a thread on this info.Lots of folks would probably be interested.

Zach



underthetire
Zach, if you get the v3 board on the megasquirt, it will run low impedance injectors. Diy auto tune is where I got my ms2 with the v3 board. At that time it was 249.00 for the diy kit. Takes about a full day to solder together, but was fun and pretty easy.
Dave_Darling
QUOTE(TargaToy @ Oct 12 2011, 05:04 PM) *
Was wondering the same thing about the 1.8 runners being larger. They "seem" larger but when I threw my caliper on them, I got mixed measurements (mostly because I can only get on the bends on the runners in the car).


The 1.8 uses the same manifold boots as the 2.0 does. (Those are the short and fat hoses from the intake runner pipes to the plenum.) The 1.7 uses different ones that have a smaller ID. So the inboard ends, at least, of the 1.8 pipes are larger than those of the 1.7 pipes.

--DD
VaccaRabite
I already have an MSII v3.52 "factory" built box from DIY, a JimStim board for testing, and the V3 main board wire harness. I picked this stuff up from Jake over the summer from his personal stash, since he ddcided not to build a test mule with it.

Zach
VaccaRabite
I am retrofitting this thread to be my full on conversion thread, documenting my change from dual 40 Webers to MSII fuel injection.

Here is what I have so far, and what I need:
HAVE:
  • MSIIv3.52 pre-built box.
  • JimStim board for testing the MSII box
  • V3 main Board wire harness.

    Will soon have:
    Injection system off a 1.8 914, from which I will use
  • Throttle body
  • Intake Runners
  • Fuel Injectors (unless I find they don't flow enough fuel)
  • Fuel Rail
  • Fuel Pump (maybe - Joe may still need it for himself)

    Stuff I need:
  • TPS or MAF or MAP sensor
  • 4 wire O2 sensor
  • Bung welded into exhaust
  • Fuel Pump (Maybe, see above)
  • Other stuff I don't know about yet
The engine is a 2056, particulars as follows:
Built on 1.7 heads.
Jake's 9530 cam (carb cam similar to Web 494)
Mallory optical ignition
ACCEL (UltraCoil) coil.
SSI exchangers for exhaust.

My goals for this project are to have near stock intake noise volume, better cold starting - especially in cooler weather, negate the bad effects or Ethanol on carbs, teach myself something about fuel injection.

Since I already have a pretty good ignition system, I am not going to go after crank fired ignition at this time, but I am not ruling that out for the future.
Dr Evil
popcorn[1].gif
moparrob
I've got a nice fuel pump you can have if you decide you need it. It came with my car which the previous owner had converted to ITB fuel injection. However, when I bought the car it had no engine, so I built a six with Webers. I'm using a Holley low pressure pump.

The extra pump is a Bosch 0 580 254 979 which is rated at 165 liters/hour and maintains pressure at 5 bars (72 psi). It came stock on 78-79 930's and 79-82 924 Turbos. The pump was probably used for about 500 to 1000 miles of driving.

Anyhow, the pump looks like this:

IPB Image

This is a stock image, though. Mine has -AN fittings on the intake and exhaust ports, plus a mounting bracket.

They cost quite a bit new but I really don't need it and I have noticed you contribute quite a bit to this site's content. So if you want it just pay for postage (probably $10.) and it is yours.

Let me know.

Rob
VaccaRabite
Rob, consider me letting you know I want it. PM me details.
Zach
moparrob
you've got mail....
jcd914
QUOTE(moparrob @ Oct 12 2011, 08:17 PM) *

The extra pump is a Bosch 0 580 254 979 which is rated at 165 liters/hour and maintains pressure at 5 bars (72 psi). It came stock on 78-79 930's and 79-82 924 Turbos. The pump was probably used for about 500 to 1000 miles of driving.


That is CIS pump and will overwhelm a 914 fuel pressure regulator and probably most any EFI fuel pressure regulator.
I used a similar (or maybe the same) pump on a MoTec install on a 3.4L 911 turbo engine using 3.2 Carrera fuel rails and pressure regulator. It was too much fuel at idle and had to have an additional regulator added to keep pressure down at idle.
Under load it was OK since the engine used a lot of fuel but at idle pressure would build up.

Jim
a914622
I know a guy that pulls the stuff needed to make the maga squirt dyi and sells them on ebay. He pulls everything off the fords. The ztec engine has the right timing wheel and pickup, coil packs, tps, and a funky sensor that tells the amount of eythanl in the gas.
The fuel pump out of the volvo turbos have a great fuel pump and filter setup.

As far as a real quiet intake, The filter box out of a dodge caravan (90s) works great. The same noise problem in the subaru/vanagon setup. I turned the bottom housing around and ran a hose out the intake side to get the sucking sound farther out. You could almost run it all the way back to the lights?


jcl
Valy
QUOTE(jcd914 @ Oct 12 2011, 10:03 PM) *

QUOTE(moparrob @ Oct 12 2011, 08:17 PM) *

The extra pump is a Bosch 0 580 254 979 which is rated at 165 liters/hour and maintains pressure at 5 bars (72 psi). It came stock on 78-79 930's and 79-82 924 Turbos. The pump was probably used for about 500 to 1000 miles of driving.


That is CIS pump and will overwhelm a 914 fuel pressure regulator and probably most any EFI fuel pressure regulator.
I used a similar (or maybe the same) pump on a MoTec install on a 3.4L 911 turbo engine using 3.2 Carrera fuel rails and pressure regulator. It was too much fuel at idle and had to have an additional regulator added to keep pressure down at idle.
Under load it was OK since the engine used a lot of fuel but at idle pressure would build up.

Jim

agree.gif
VaccaRabite
Just finished pulling the engine. We are officially under way. Carbs are up in storage as is the Tangerine cable sync. For sale by the way. Need money for EFI bits.

Joe, your 1.8 out yet? I need to scavenge!
jsayre914
QUOTE(Vacca Rabite @ Nov 5 2011, 10:22 PM) *


Joe, your 1.8 out yet? I need to scavenge!


Not yet. With the wife not feeling good, sick dog, busy at work, kids karate, and football....

I would love to find the time biggrin.gif

Come get what you need. All Fuel Injection is accessable with the engine in the car. I am home Tuesday as usual.

p.s. I do have another fuel pump. Both are tested and working great.

beerchug.gif
aircooledtechguy
I just finished a similar conversion for my '67 Squareback. I transplanted a '73 914 2.0L and converted it to MS2 V3 w/ EDIS using the stock 2.0L runners and a 1.8L plenum (clocked about 3/4" on the fwd mounting only so the runners would line-up) and a slightly modified 2.0L TB. I get my CLT temp from the LH valve cover. I switched to a Walbro pump. The injectors are yellow-top Type-3 D-jet injectors which flow almost as much as the stock green-top 2.0L type. I have had no fuel starvation with these

IPB Image

I've been meaning to pull it all apart to get it all powder coated, but I just enjoy driving it too much. . . It drives like a scalded cat!! When I get the car painted I'm going to have the pin-stripper badge it "SB Type-P SS" ("Squareback, Type-Porsche Super Sleeper").

Mine has EDIS, but if you want the MSQ-file, shoot me your e-mail address and I'll send it to you. It'll get you in the ball-park for your motor and have a good starting point anyway.
charliew
I'm just reading along and hopefully learning if only I can remember. I'm curious how a fuel pump can overwelm a pressure regulator if the return line is big enough. My son runs a BIG pump on his sti and still uses the stock lines. Oh yeah I forgot his pump is modulated.
Brodie
Zach, There are some calculations to determining throttle body size.

cfm = (Max RPM x Volumetric Efficiency x Cubic inches) / 3456

or

max area of opening = (cfm x 2.4) / 300 feet per second

Use 85% for an average guess on volumetric efficiency. If you have information on what the actual volumetric efficiency is use it, but I'm not sure how to get it.

I would say that you need to calculate the area of the ID of all of the runners and make sure that they are at least as much as the throttle bottle. I would think that even a bit larger would be better. You want to flow as much air through the runners as the throttle body.

Don't oversize the throttle body by too much because at fully throttle it's fine, but at idle you bump the throttle just a little bit and a large amount of air rushes in. I would think that would cause some grief.

I haven't done this for myself yet because I have to get my car built from scratch, but when I do, these calculations will come in handy. (I think!)

I don't know if this will help you any but through my research I found a few tidbits here and there, and wanted to pass them along.

Good luck!
VaccaRabite
Okay, I've not updated this thread since November.
Could be I am maybe a bit embarrassed by my lack of getting-shit-doneness?

So there has been a bit of a change of plans.
I am going to be running McMark's Microsquirt setup.
I fought with myself for nearly 6 months before admitting that having a setup that took the engineering out of this would be a much better way to go right now. Mark's system gets me crankfire ignition, coil on plug, a weather sealed MS box that can live in the engine bay, a pre-built wire harness, and a huge bit of cussing and experimenting taken out of the picture.

The MSIIv3 box I have will go on the Jeep. Or I'll sell it. Dunno yet.

I just put my Mallory Unilite system up for sale in the classified section. NO BACKSLIDING!

Years ago I ran one of Chris's stainless fuel lines through the tunnel. For years I considered selling the return line. Almost gave it away twice. Glad I didn't. I was not looking forward to running it in, but tonight I did just that. While I had the tank out, I also pulled all the carb related fuel stuff out.

One kinda scary thing... The fuel filter I put in ~2008 was clearly not intended for ethanol. It looked like this when I pulled it out.
IPB Image
The inlet and outlet were both deformed and degraded from the fuel. If you are using this type of filter - CHECK IT!

Also, there was a LOT more rust in the tank then there was in 2008 when the tank went back in the car. Not nearly enough to be worried about, but enough that I was really surprised when I put a flashlight in and looked around. Stupid alcohol.

Zach
JamesM
025 133 067a wink.gif


if you can find one
VaccaRabite
A quick update.

Yesterday I picked up a used, but in excellent shape, Triad muffler from one of our local members.

I have made 2/3rds of the payment to McMark for his excellent Microsquirt driven EFI and electronic spark. Will be paid off by the end of the month.

I stopped by my machinist today and he promised my heads would be done next week. Of course, its easy to say "next week."

I gave my engine tin to Joe to take to his powder coater in Baltimore. They did a great job on his stuff.

This is really starting to move together. I'm getting excited.
McMark
mueba.gif
ConeDodger
You'll like it! Mark really has something in that package. I would consider it over carbs on a relatively stock car anyday.
Dr Evil
Just in time to store it for winter!
VaccaRabite
If it runs in the winter that means it is likely to run in April. And that is what I really care about.

Zach
hot_shoe914
So, do you still want the loaner motor? confused24.gif If not, I have a guy who wants to use it to build a megasquirt system. Still yours to use if you want it though. beerchug.gif
VaccaRabite
If I have the loaner motor, I won't need it.
If I dont have it, my car won't be driving at Hershey.

Kinda like taking an umbrella on a cloudy day to ensure it does not rain.

At this point, if there is someone that needs the motor, I can't justify having it on hand for insurance. Especially if you are going to ship it cause you are not coming this weekend.
hot_shoe914
QUOTE(Vacca Rabite @ Oct 18 2012, 10:17 PM) *

If I have the loaner motor, I won't need it.
If I dont have it, my car won't be driving at Hershey.

Kinda like taking an umbrella on a cloudy day to ensure it does not rain.

At this point, if there is someone that needs the motor, I can't justify having it on hand for insurance. Especially if you are going to ship it cause you are not coming this weekend.

Well, I will keep it on hand for you until you know for sure. They are in no hurry for it as they are Volvo guys. He was just going to design a ms system for us d-jet guys as a favor to me. I have it on hand in my storage unti on an engine stand in plug n play condition. Something happens and you need it, I will strap it to a pallet and send it right away.
VaccaRabite
Last week I picked up a triad muffler from Bill in Mt Airy.

Over the weekend I blasted it clear of old paint and what little rust it had. I also got a free, used O2 bung from a fellow teener this weekend at ECC.

Today I cut in the opening for the O2 sensor. I cleaned up the used bung and welded it into pace. I could not find a 18mm fine bolt, so I tried to be very careful not to warp the bung while welding it into place.

Then I put the first coating of grill paint on it.

IPB Image

IPB Image

IPB Image

I actually made real progress today!!!

The second and third coats of paint will come ay a later date. The first was put on quickly today to keep it from rusting up since I had blasted the metal bare yesterday.

Zach
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