L20b + Megasquirt + TBI

[copacetickid]

I'm starting to gather a parts list for my EFI conversion in my 620. I haven't nailed down much yet, but I'm fairly sure I want to try to go the route of throttle body injection to make the manifold issue easy. I also own a '88 subaru GL with a EA82 with SPFI, which is where I got my inspiration. Before I go too far down this road, I want to make sure this will work.

 

Since those subis are all over the place in WA, I figured it'd be cheap to get all of the components and sensors necessary off of that engine. My main concern is that since the ea82s are 1.8L, the throttle body itself isn't going to be big enough for my l20b. The throat at its narrowest part (the butterfly valve) is only around 1 3/4", which worries me slightly. However, I'm not doing this for performance as much as efficiency. I did a rebuild of my motor recently and it's completely stock, so I'm not looking to push it very hard. On the other hand, the beauty of EFI is that performance doesn't come at the cost of efficiency, it's just a matter of finding the right map. I don't want the throttle body to be a significant bottleneck when merging on the highway.

 

There's more than a handful of people that have done EFI conversions on this forum, but I haven't seen a TBI one yet. Just wondering what people think. Does anyone know of other makes with TBI that would match up better?

[Skib]

I have a whole box of L6 50mm TB's (might have a few other random ones in there as well) if you want some larger one to tinker with

[datsunfish]

I always thought the subaru would be a simple conversion for either a datto or an air cooled vw. 1.8 should be close enough for a L20b. Just put on a big cold air intake since the subaru tube necks way down. I had that stuff for the longest time but never got around to it so I tossed it. Its easy to break a subaru boxer/pancake motor so it should be way easy to find. Give it a shot and let us know how it goes.

[72240z]

I'm pretty sure there is a Nissan bolt on solution here. Not saying thats better, just easier I think. No msns needed.

 

You can take the efi of a z22/24i, they are cheap, simple, reliable and plentiful.

 

There is a company on ebay (webercarbsdirect) and I'm sure online as well selling a Weber 32/36 to lz22/24i & conversion kit. You can either ask them if they will sell you just an reverse adapter or you can make one yourself.

 

A 3/8 thick piece of steel with matching ports, they are pretty close stock. Four countersunk hex head bolts to hold adapter to the manifold then 4 regular bolts or studs to hold the tb down to the adapter. Actually pretty easy imho.

 

Leaves you good to go without any of your worries unless I missed something.

The subi idea is cool but the Nissan rt is so easy and already suited to the task, Idk, that's the way I would go.

If your deadset on using a more custom method and msns I would really think it better to take full advantage and use multipoint not tbi. To use tbi to me means simple as possible and in that case might as well use stock proven and tuned efi. One adapter and a few spliced wires your efi. :-)

Edited April 9, 2009 by 72240z

[datsunfish]

I have a z24i tbi and its pretty bulky with lots of crap. I remembered the subie stuff being pretty simple. Its hard to get into it with a good weber sitting there.

[72240z]

I have a z24i tbi and its pretty bulky with lots of crap. I remembered the subie stuff being pretty simple. Its hard to get into it with a good weber sitting there.

 

That's fair to say, but its not a negative. One of the biggest bonus's to tbi is that 90% of the efi components are on the actual unit. The EA82 has the same things on it, it's just smaller. The z22/24i tb was designed to be used for the vg30i as well, they are identical, so its big enough to flow for a 3.0 where as the subi is compact and small enough to flow for a 1.8. The tb off the z22/24 is also close to the same size as the weber it would be replacing as well so, no harm done far as I see it, the efi components are going to be their regardless of the unit used. In my eyes then it's better to use a tb big enough for 3.0 and proven on a 2.2/2.4 then one build for a 1.8. Not just that but the bolt pattern and port on the EA82 is completely different where as the z22/24 unit is almost identical just a little bit bigger.

 

I mean it's not my project I have no idea what copacetickid is looking for or wants. But based on the initial post and my subsequent suggestion this is how I'm seeing it.

 

 

-----------------------------EA82 -----------------------------------------------Z22/24i/vg30i--------------------------------

Edited April 9, 2009 by 72240z

[copacetickid]

Thanks for the info 72240z, I didn't know about the TBI on the z22/24. Sounds like maybe a better size match, not to mention the bolt pattern being close (the EA82 TB is gonna need a crazy adapter). It looks like it comes off of a post-'85 hardbody or a late model 720... I guess I'll start looking for one of those years at the yard. Are they really that plentiful?

 

Looking at the pictures you posted I'm confused. I haven't heard of a 'wax' type fast idle cam... is it coolant temp controlled like a thermostat? Weird that it's even on there, I thought all EFI setups had idle air control and just adjusted the pulse width for enrichments... And what does the fast idle valve control if not air or fuel?? :confused:

 

Skib: did L26s have TBI, or are the off of something else? Are they complete enough that I could get one running? :D

[72240z]

Thanks for the info 72240z, I didn't know about the TBI on the z22/24. Sounds like maybe a better size match, not to mention the bolt pattern being close (the EA82 TB is gonna need a crazy adapter). It looks like it comes off of a post-'85 hardbody or a late model 720... I guess I'll start looking for one of those years at the yard. Are they really that plentiful?

 

In your area they are, in mine I have to hunt a little but I have never had a prob finding a part. You can find the ones off the z22e in 81-83 200zx the z24 is from 85 on in the hardbody, 720, pathfinder and the van. Pretty decent model range for parts finding. Some parts are interchangeable too. Like when I bought my d21 vg30i the maf on it was from a z24, I replaced it with one from a vg30i but it ran the same, problem free. I'm pretty sure just the injectors are dif between models.

 

Looking at the pictures you posted I'm confused. I haven't heard of a 'wax' type fast idle cam... is it coolant temp controlled like a thermostat? Weird that it's even on there, I thought all EFI setups had idle air control and just adjusted the pulse width for enrichments... And what does the fast idle valve control if not air or fuel?? :confused:

 

The wax type physically holds the throttle open a tiny bit when you cold start so the rpm is a little high. That aids in warming the truck up faster. It slowly drops the idle little by little over say a 3 min period as the coolant temp comes up. A coolant line runs to it. After that its inactive. The FICD adjusts using the same method as the z31 where in a separate port air passing by pushed on a ball and spring sending a signal to the ecu and adjust. I actually replaced mine and the idle up with one from a z31. That's part of the advantage to keeping it nissan too, lots of 80's stuff is interchangeable.

 

You can tune the wax out if you like, there is a adjustment screw. It's a neat feature if you live in a cold area though, truck warms up faster and you don't need to hold the pedal.

 

Also after looking at 32/36 to z24i adapter its looks like for z24i to 32/34 flange you may not even need an adapter. Provided there is enough meat you could drill, tap and stud the stock mount, do the slight port matching with a drill or dremel and call it a day.

 

It's not really too surprising its all so close, I feel that throttle body was Nissans EFI copy for the 32/36 that had already served them well. It looks so similar.

Edited April 10, 2009 by 72240z

[City Hunter]

that thing looks like a nightmare. Why not turbo it and use a starion turbo tbi setup....?

[Guest jaimesix]

This Datsun 610 has an L series with megasquirt in it.

 

 

 

 

Jaime.

Edited April 10, 2009 by jaimesix
Added pix

[copacetickid]

...

 

The wax type physically holds the throttle open a tiny bit when you cold start so the rpm is a little high. That aids in warming the truck up faster. It slowly drops the idle little by little over say a 3 min period as the coolant temp comes up. A coolant line runs to it. After that its inactive.

 

...

 

You can tune the wax out if you like, there is a adjustment screw. It's a neat feature if you live in a cold area though, truck warms up faster and you don't need to hold the pedal.

 

So since the wax type cam is directly affected by coolant temp, it sounds like the cold-start enrichments aren't tunable by computer. One of the coolest parts about the MSII is that you fine tune your control over everything, including warm-up enrichments. It would be a shame if I couldn't use that feature... I've had serious issues tuning my carb's fast idle/choke, and it's half the reason I want to move to EFI.

 

This Datsun 610 has an L series with megasquirt in it.

 

 

...also with multiport injection?? I'd probably go that route if I could, I'm just no fabrication wizard. Also not ready to shell out $400 for a custom mani on top of the six or seven hundred for the MSII.

[72240z]

So since the wax type cam is directly affected by coolant temp, it sounds like the cold-start enrichments aren't tunable by computer. One of the coolest parts about the MSII is that you fine tune your control over everything, including warm-up enrichments. It would be a shame if I couldn't use that feature... I've had serious issues tuning my carb's fast idle/choke, and it's half the reason I want to move to EFI.

The cold start "enrichments" are controlled by the computer just like all the others, as I say the wax cam is just to increase idle manually for the 1st couple min of start up to aid in warming the motor up. That said though the complain isn't z22/24i specific, what stock efi allows you to tune that parameter? That's what the apexi a/f controller is for :-). Like 50 bucks used.

 

I understand wanting msns though, it is nice to have the full control. As I say though msns on tbi I feel is a waste. All that trouble to tune 1-2 injectors lol.

 

 

...also with multiport injection?? I'd probably go that route if I could, I'm just no fabrication wizard. Also not ready to shell out $400 for a custom mani on top of the six or seven hundred for the MSII.

 

6 or 7 hundred for ms on that motor is RIDICULOUSLY too much and self defeating. For 6-700 you can run a stock z24/ka, 400 on top of 6-700 you could run a ka with nistune. You need the most basic msns to run that motor you could buy 3 for 700.

 

I understand some people like to stick with the L, it's a fine motor and all but when $700 ms with $400 multi point injection manifold plus injectors and fuel rail etc.. comes in I bow out because I feel it's a serious waste of money.

[Guest jaimesix]

 

 

 

 

6 or 7 hundred for ms on that motor is RIDICULOUSLY too much and self defeating. For 6-700 you can run a stock z24/ka, 400 on top of 6-700 you could run a ka with nistune. You need the most basic msns to run that motor you could buy 3 for 700.

 

I understand some people like to stick with the L, it's a fine motor and all but when $700 ms with $400 multi point injection manifold plus injectors and fuel rail etc.. comes in I bow out because I feel it's a serious waste of money.

 

 

What one person sees as treasure another sees as trash. In the same way you think spending 1100 dollars for improving an engine is a waste of money, other people would tell you that spending "any" money on your old Datsun is a waste of money.

 

Jaime.________________________________________________________

[DRIVEN]

I know it isn't Nissan or Subaru but GM TBI is simple and dirt cheap. The wiring is basic and aftermarket PROMs are readily available. Cavaliers and other small/mid-size cars had 1.8s, 2.0s, 2.2s and 2.5s. S10s also had 2.2s and 2.5s. The right wrecking yard on the right day could probably yield the entire system (plus pocket-sized spares) for less than $100. Just a thought.

[FoxyRoadster]

I'm converting my R16 over to run EFI with MS.. its worth it on the fact I don't have to change anything out besides a few parts and get to keep the original motor in the car... Not to mention I have plans for running boost...

 

 

I plan on using the ford EDIS setup and MS2. I'm going to be watching this for sure as I just like to see these older datto motors converted to EFI.

[72240z]

I knew I would catch flak for saying that. It's not that I'm saying converting it over to efi or even multipoint efi is a waste, just the cost involved. It CAN be done WAY cheaper and in that case to me its worth it but when we start talking over a grand JUST to go efi I say to myself why? Efi kills the retro or purist appeal and to gain the efi driveability/reliability/tuneability you don't need to spend anywhere near a grand, let alone over.

 

I did say in my opinion too not that it was right or wrong. Some people on here have some set ups that are down right inspiring whether I agree with the need/cost or not. Never the less since I was already hip deep in this thread I felt the need to voice my opinion on spending over a g on the project. ESP when you take into account the simple goals. We aren't talking a track car but a DD that is tunable and non problematic. Unless I'm mistaken anyway.

[lynchfourtwenty]

This Datsun 610 has an L series with megasquirt in it.

 

 

 

 

Jaime.

 

thats down right bad ass :fu::cool:

[slayer]

any idea what efi they are using on that 610.... i messaged them to find out on youtube but i never get replys back from people on youtube.

[FoxyRoadster]

I knew I would catch flak for saying that. It's not that I'm saying converting it over to efi or even multipoint efi is a waste, just the cost involved. It CAN be done WAY cheaper and in that case to me its worth it but when we start talking over a grand JUST to go efi I say to myself why? Efi kills the retro or purist appeal and to gain the efi driveability/reliability/tuneability you don't need to spend anywhere near a grand, let alone over.

 

I did say in my opinion too not that it was right or wrong. Some people on here have some set ups that are down right inspiring whether I agree with the need/cost or not. Never the less since I was already hip deep in this thread I felt the need to voice my opinion on spending over a g on the project. ESP when you take into account the simple goals. We aren't talking a track car but a DD that is tunable and non problematic. Unless I'm mistaken anyway.

 

 

Buying everything new and such might set you up close to 1g for EFI on an older motor, I cringe at anything over that price that isn't involving a turbo/superchager or some kinda motor work..... Should be about 6-700 counting ECU and part cost, if you do it all yourself.

 

Basically for me it was.. swap to KA24 or go EFI.. I like the R16 after tinkering with it and thought it had loads more life and power available with a little work.

[copacetickid]

Yikes, I didn't want to start an argument. Everyone is certainly entitled to their opinion, and 72240z, I greatly appreciate your input. Without it I wouldn't be an avid reader of this forum. :)

 

For me it's not really about sticking with the L motor, or the retro/purist appeal. For me it is about driveability/reliability/tuneability, but also about the ultimate level of control. Megasquirt is so amazing because it's totally open source and transparent, all you have to do is buy the hardware and you get the whole package. No proprietary software, no mysterious 3rd party ecu chips, you get to see exactly what is going on, and adapt it to any hardware you want. If I want to use the chip to integrate a kill switch or a clock or whatever into my car, I can because there's no restrictions to changing the firmware; more than that, there's a forum of hundreds of people who are probably willing to help you out with writing new code for it.

 

Before I got my datto, I didn't really know shit about cars, and because it was the first car I owned that was easy (and a joy) to work on, I've learned a ton of stuff through it. That above all is what this project and all my other hobbies are about: learning anything and everything I can. I love to achieve maximum efficiency within a given system, and my 620 is that system. I know it's a little silly, but I feel a sense of loyalty to my l20b, because it's mine and I'd be letting it down if I junked it for another motor. I am not a performance-aholic, 1952cc is probably too much displacement for my mpg-oriented attitude anyway. I do have a budget yes, but in my mind if I'm going to do this project I don't want to feel limited by being forced to use a stock efi setup, or even one that keeps me from looking at the code that literally drives my truck. As for using tbi vs multiport, from what I've read there's very little to gain for the added complexity. A multiport setup takes a lot more tools than I have, experience, and money to do right. Not that I'd choose tbi if I had the right tools, the time to gain the skills, and the money either.

 

Anyway, that was my itch over the wax type fast idle cam: it's something that I can't control and tune with the computer. I'm new to efi in general, so my thinking was that in order for the computer to control fuel enrichments, it has to be able to control the corresponding air flow, hence cars with an iac. The throttle is opened slightly by the fic, which lets enough air go by (that the air flow sensor reads) to complement the extra fuel the ecu is able to add for cold-starts. In essence, the same as holding your foot on the accelerator to warm up the engine on a cold day (which is what I currently have to do in my truck). Check me if I'm wrong on this though.

 

And at least I'm not going to be spending as much as fineline probably did, bless him :D

[Z-train]

I know it isn't Nissan or Subaru but GM TBI is simple and dirt cheap.

 

And they were no better (or worse) than a carb).If you are gonna go this route then step up to port injection.The majority of MS's feature will be defeated by using a TB.

 

I've got a KA-24 with the computer & harness for sale.........:lol: