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#21 bluerat

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Posted 23 November 2013 - 08:37 AM

G'day Mate, we have just gone through/done all of this and the first thing I would do is find someone local you can trust to help you set it up and tune it, chat to the local Dyno guy as well and see what they use and recommend, maybe, if you haven't already, join the local CAMS car club and see what everyone there uses. I went with Motec, simply because there are 10 local guys who use them, have all the cables, programs etc. The guy who did it for me has it on his own 200B rally car, has set up heaps, along with the auto sparky I used. We had a good relationship with EFI Hardware, brought gear off them and took their advice, same with Motec with the Lamder, sensors, etc so it was really just plug in and play. I started off trying to do it on the cheap, and in the long run it cost me more than getting the right advice straight up, and it works perfectly.

We used a 'Scando' modded RB30 Dist and VL (turbo) fuel pump and 6 x LS-1 Coils. We run everything through the computer which logs oil pressure, water temp and all the other hoo-harr and the only tuning so far is on the road using the Lamdar. Also using the Motec wiring harness etc was a smart move.

Hodgo

#22 Zedman240®

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Posted 23 November 2013 - 11:37 AM

I'm using the L28ET distributor; they can be found if you are looking hard enough. I know where there are several units if you need one now. As for the throttle bodies, I'm using the EFI Hardware ones. Mine are the older version without the air bleed screws. They work perfectly for me anyway and if you look on the net constantly, you will find some for sale second hand. Injection Perfection also manufacture Weber styled ITB's; you can always shop around and find the best price.

#23 KatoKid

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Posted 23 November 2013 - 06:44 PM

http://www.extrudabo...n-L6-for/Detail

These...don't know if they are any good but reasonably priced. Still need ECU, ignition, fuel system plus dyno time  = $$$$$$

#24 Zedman240®

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Posted 23 November 2013 - 07:54 PM

http://www.extrudabo...n-L6-for/Detail

These...don't know if they are any good but reasonably priced. Still need ECU, ignition, fuel system plus dyno time  = $$$$$$


ECU=~$500
Surge tank / lift and EFI Pump and lines = $250
Ignition = L28ET dizzy, Ignitor, coilpack leads etc $400
Some new but most parts are second hand and dyno time is needed no matter what you have setup be it carbs or the EFI but the difference with the EFI is it's all done with a laptop and don't need to pull carbs apart every run to change jetting..

#25 Bozo

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Posted 23 November 2013 - 10:28 PM

Buy an RB25. It may end up costing $500+ than setting up ITB's, but you will have a newer engine with perks over the 'L'egacy series engine that's currently sitting in your engine bay.

Scoota G should be able to work something out for you if you're serious.

#26 gav240z

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Posted 24 November 2013 - 12:00 AM

Buy an RB25. It may end up costing $500+ than setting up ITB's, but you will have a newer engine with perks over the 'L'egacy series engine that's currently sitting in your engine bay.

Scoota G should be able to work something out for you if you're serious.


Yeah but where is the fun in that?

I'm interested to see how you guys go, I want to try building a Megasquirt EFI set up on my 240z. I hear what you guys are saying in terms of it being a headache but I'm very eager to learn.

#27 Six_Shooter

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Posted 24 November 2013 - 01:38 AM

Wow, lots of ney-sayers here.

I realize that the cost of living is a little higher in Australia, compared to here, but it's all relative, I also believe that pay is higher as well...

That being said there is a lot of advice that is being spout as "required" and "the only way to do it" when it's not. There are many ways to accomplish this, and it's usually only after you have built and installed several set-ups that it becomes clear how to do it easily, it's that experience thing. ;)

For the record I have built or been involved in building and tuning several custom EFI systems, for engines that never had EFI, to conversions from difficult to tune EFI to easier systems.

I tend to use Delco (GM), that would be Holden for you guys ECMs for my conversions. They are plentiful, they are cheap, and they are extremely reliable. They are also easy to tune, and can be done cheaply, if you don't care about real time tuning, also included is onboard diagnostics. I am running my turbo L28 on a Delco ECM and have for about 5 years, works great. Why am I bringing this up? People tend to "Oh I have to go aftermarket to inject my old engine". No, no you don't, you can adapt other OEM EFI, and the great part about that is that the parent companies have spent Millions on development, to make sure they are reliable and perform well. The DIY community then takes these and hacks them for tuneability and adding features.

Personally I'm using OBD1 ECM, that is running wastespark DIS and bath fire injection, this was cheap, reliable and don't need "credits" to tune it. I could have easily went to an OBD2 ECM that would allow for SFI, but it's just not needed.

Thanks for the "option #3" link, I was not aware of this company and I think I will use these parts for my planned custom ITB conversion on a V6 engine I plan to use. :D

Getting a solid map signal is not that difficult, especially since you will be making a manifold or modifying and exiting one. You can run a tube from each runner below the throttle blade (but above the injector), to a common vacuum block, that is then fed to the MAP sensor. If you want to use an IAC valve, you need to replicate this set-up again, and have a separate block for the IAC valve. The reason for this is to not affect the MAP signal with the IAC valve directly. I do know of one person that made both work on a common IAC/vacuum plenum, but it was definitely not ideal.

Spark triggering and control is not that difficult either. When I first installed my system I ran out of time to get the DIS in off the bat, and so I used an electronic dizzy from an L28, from a '77 or so. I locked out the mechanical and vacuum advance. I then triggered a GM ignition control module, that fed the DRP (Distributor Reference Pulse, AKA RPM reference) and allowed the ECM to control the timing of the ignition. I then swapped in my DIS the following winter, that involved a custom (pretty simple) trigger wheel, using the same ECM, with a couple settings changed for the DIS offset. Aftermarket systems also have this ability. Some systems have the ability to have sequential spark control in addition to sequential injection, such as the Megasquirt 3.

If this was my first build, I'd do plenty of research, but I would hold off buying the ECM part, if I was going aftermarket, until most of the mechanical part was squared away. The reason for this is that the aftermarket changes so often, that the ECM you buy today may be "obsolete" next year, or at least a "better", "more improved" version may be available, that may work better for you. If I was going with an OEM set-up, such as what I like to do, then grabbing the ECM and related hardware can be done at anytime. I would plan which system I wanted to start with, even if the plan was to hold off on buying it. The reason for this is that certain ECMs will only work with certain hardware. Again, I'll go back to my Delco (GM) ECM, the ignition is easiest to interface with GM parts, due to the signals between the ICM (Ignition Control Module) and the ECM being somewhat specific. Going aftermarket you can usually use just about anything you can get your hands on, with a few exceptions. I do know of a universal adapter that is said to allow any ignition system to be used with a Delco ECM though. I'm not sure if it's released to the public yet though.

Other sensors and such, are less incidental, since most will use the same threads to attach, or be easily adapted, like coolant temp, manifold temp, TPS, etc, with a few specific exceptions, again researching what you want to use as a system, will make this easier in the end.

I always find it entertaining when people say "You NEED to dyno tune your set-up". Why? Are you driving your car on a dyno? I'm not, I'm driving mine on the street, so that's where I tune it. A dyno is great if you want to get max power numbers, but does next to nothing for driveability. Even "load cell dynos" will only get the tune so close. The best data is retrieved from where and how the vehicle will be driven. This is why I tune on a drive around the city and highway as the vehicle will be used. When I tune for other people I sit in the passenger seat and tell them to drive as they normally would to get a tune that suits that person. I do get the driver to drive in certain ways sometimes just to get into certain load points and RPM points that wouldn't normally be hit, just to get a wider range of tune, but that only usually happens when there seems to be a small hurdle to get tuned out.

Real time tuning is great and is one element I look for when deciding on an ECM to use, again this is another reason I like my Delco ECMs, with an EPROM Emulator, I have real time tuning that I can see the changes immediately as they are made. Obviously if I'm driving, I do it the old way of looking at logs or rather, keep track of what happened and when, pull over, make a change and re-test.

With careful planning an EFI system that works great, is reliable and is inexpensive can me put together.

#28 juz0

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Posted 24 November 2013 - 08:46 AM

I've actually had an ITB set up finished using a triple weber manifold and rb26 itb's.
Unless you can do the machining and welding yourself its cheaper to buy a ready made kit.
I'm pretty sure my total cost just for the itb setup is around 3k and the biggest cost was getting it all together and set up.
If i was doing this again I would just buy an OER kit.

I still have to buy an ECU, different injectors, coil packs, make the wiring loom etc etc.
It's not a cheap conversion!

for the trigger I've got an L28et dizzy with optical disc.
should work alright once it's all together

take a look at my last post on this thread and you can see what it looks like

http://www.viczcar.c....html#msg138049

good luck!

#29 DreamZproject

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Posted 24 November 2013 - 08:49 AM

Woooooow. Several amazing replies here!
Yes there's still more for me to learn, but I've been pointed in the right direction no doubt!
I'm sure I'll come back to this thread in a couple of weeks and a few more questions, but
This is FANTASTIC!
Thank you very much for the time guys! I feel somewhat more confident in going ahead with
This at some point in the near future.

#30 1600dave

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Posted 24 November 2013 - 11:52 AM

Buy an RB25. It may end up costing $500+ than setting up ITB's,


Buy an R33 skyline, it'll be way less than buying / modifying / maintaining an old zed  ???

I'll see if I can find my set of Toyota ITB's and measure for you - I vaguely recall that they weren't far off / may have been the same as webber pattern ? I could be wrong, its been a while.

#31 Bozo

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Posted 25 November 2013 - 09:09 AM

Buy an R33 skyline, it'll be way less than buying / modifying / maintaining an old zed  ???


Buy a bicycle, it'll be way less than buying / modifying / maintaining a car.

What are you implying? That a half assed mod is superior to an engine conversion?

If you're really that keen on being a Datsun/Z-Car enthusiast; you would retain the vehicles 'original' parts. In this case the original fuel system being the twin flat top carburetors with the air box.



#32 Six_Shooter

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Posted 25 November 2013 - 09:17 AM

If you're really that keen on being a Datsun/Z-Car enthusiast; you would retain the vehicles 'original' parts. In this case the original fuel system being the twin flat top carburetors with the air box.


I don't agree with this statement.

I love my Datsun Z-car, but I will never leave it stock, which I haven't. I also have many more modifications planned, most that will not be seen.

#33 DreamZproject

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Posted 25 November 2013 - 09:53 AM

Original or not (I do see both points) doing it this way means I don't have to get the thing engineered = less money and
Stuffing around, plus I can drive it whilst still on my P's.
I also want a really nice sounding engine, and I've never heard an RB that I like the sound of...

#34 luvemfast

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Posted 25 November 2013 - 12:16 PM

Why go ITB's at all?
For what you want, an L28 manifold with the big plenum will suffice!

#35 1600dave

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Posted 25 November 2013 - 12:57 PM

Buy a bicycle, it'll be way less than buying / modifying / maintaining a car.

What are you implying? That a half assed mod is superior to an engine conversion?

If you're really that keen on being a Datsun/Z-Car enthusiast; you would retain the vehicles 'original' parts. In this case the original fuel system being the twin flat top carburetors with the air box.


Sorry, just a flippant comment.

Perhaps a half assed mod (or maybe even a well-engineered mod if he gets some good advice to his original question) may be what the original poster wants.

Anyway, a bit of info.

Toyota ITB's come in two sizes apparently, mine have a 42mm butterfly (don't know if these are the larger or smaller ones). They are set on 88mm centres, weber flanges are on 90mm centres. "bolt pattern" on the flanges of the Toyota throttle bodies and webers are also different. What this does mean however, is the it should be simple enough to use a "spacer" of aluminium to adapt both the bolt pattern and the centre spacing of the Toyota ITB's to a weber manifold.

The Toyota ones are true "individual" throttle bodies - ie 4xthrottle rather than 2 lots of 2 like weber carbs, so you may be able to spread the carbs out a few mm to match the weber flange spacing (depending on how the linkages, etc, will handle being a few mm further apart). This only matters for the "pairs" of throttle bodies that end up next to each other (ie that replace a weber carb), you will still need to work out how to sort the linkages to spread the "pairs" further apart - how far apart will probably depend on what weber manifold you use.

So, just cut the spacer to size, bolt it onto the weber manifold, a little judicious shaping to take up the few mm of difference in spacing if needed, and then bolt the Toyota ITB's onto the other side of the spacer. You may also be able to incorporate the injector bosses into the spacer, although personally I'd weld them onto the manifold closer to the head. Easy ! Well, getting the ITB's onto the engine is easy - as others point out, there is still a lot to sort out before you get your L-series running.

#36 Zedman240®

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Posted 25 November 2013 - 06:07 PM

If you want to hear a nice RB, youtube any Rocky Auto carbed RB and it will change your mind....

#37 DreamZproject

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Posted 26 November 2013 - 07:35 AM

Oh I'm sure a carbd rb would sound fantastic!
I couldn't imagine how hard it would be to get engineered.
Great info guys, yes perhaps an aftermarket intake plenum would be the way to go...
I'll cost up everything for itbs and then compare it.

#38 d3c0y

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Posted 26 November 2013 - 10:24 AM

You can't. Carb twin cam RB is illegal.

#39 luvemfast

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Posted 26 November 2013 - 10:53 AM

You can't. Carb twin cam RB is illegal.

What about a Carb, twin cam L series?  ;)

#40 d3c0y

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Posted 26 November 2013 - 10:59 AM

No that is legal as you go off the block not the head!  8)




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