Hilux 4x4 Forum

So a quick random search and I came across a Weber retroject throttle body that basically is a direct replacement for a Weber carb (38 Dgas in my case) that has every linkage and design of the Weber 38 that is an EFI system. I find this pretty brilliant as an option for the sake of solo ventures in the bush, I could quite literally keep my old carb in a little box and if any electronics did go bonkers I could go EFI to carb in probably less then an hour. I guess the biggest challenge is getting it to SA

You would have to install an adjustable pressure regulator so that you could reduce the pressure once the carb is re-fitted. Not doing so would result in the pressure being too high for the float to be able to keep the needle valve closed, which would result in flooding. Otherwise it sounds like a good option.

I also just have to wonder that since injection will take place before the manifold, does it have just one injector? or maybe two? and how is it / are they pulsed? Will an after market ECU have provision for only one or two injectors (this is an unusual way of doing it), or will one have to link all the injector wires to the same injector / split them over two injectors - and then would the feed back through the linked cables have an effect on the ECU? Hmmmm ......

Before committing to that conversion, I would first verify how many injectors in the system and if less than 4 verify if a locally available after market ECU can accept that.

So there are 2 injectors inside the throttle body I guess acting the same way as what a carb would. I also wondered about the ecu part with it probably having to be synchronized. there is so little information on the internet about it though.
If they did decide to market it properly it could be a very interesting option for older vehicles like the Ford essex and so forth.

As for the refitting carb, I guess the regulator is the best option, but perhaps just keeping a mechanical pump aswell for trips

Rather than go that way, I would suggest rather keep a spare ECU, Igniter & HP Fuel pump if you feel the necessity. Little else can go wrong with the system.


-F_D

Hello. Just came across this thread, and as the manufacturer of Retroject, thought perhaps we could shed a little light on what it does. As has been stated, its a direct replacement for the Weber 32/36 or 38/38, so if you are replacing one of those, then Retroject will fit to the existing manifold, linkage and air filter. It comes with 2 x Weber 480cc/m PICO injectors, air temp sensor, 3 bar regulator, TPS and IACV. You will need an ECU, which just needs to be a simple fuelling ECU and if you take a speed signal from the coil then you wont need to fit a trigger disk, and lastly you just need an HP fuel supply. Any questions, please just le us know

Welcome Martin and thanks for the info.

This really sounds like a great solution. In Europe the first fuel injection Golfs came out with a similar injection system with the main difference being that the throttle body had just one injector. I used such a setup on a Porsche Spyder RSK kit car that I built and it works well. The only issue is with the turbo charger the one 800cc injector is working over 90% of duty cycle so it does not last leaving you with a single point of failure. Using two injectors is a great idea as it reduces the load (which would not be as much on a normally aspitated engine to begin with) giving you the reliability you need. Any entry level go-tech or spitronics will work well.

Mars. Actually a lot of cars in Europe had a single point injection system as a stop gap solution between carburettors and multipoint injection. Bosch, Marelli and Delco all had systems and they were universally terrible, mainly due to the duty cycle issue you mention, but at the time the focus was on getting catalysts on to everything. Twin injector does reduce the load on the injectors, and they are actually production line Weber 480cc/m units which are extremely reliable for up to about 220bhp

Well Martin I must commend you on a great idea. I wish I knew about this solution a long time ago. As it is I have gone too far down the path of converting my Spyder to multi-point EFI. I already have everything including having modded the Beetle intake manifolds to take injectors etc. BTW I am keeping the Bosch throttle body as is because it gives you a TPS and I am going to use the big injector to enrich the mixture when the turbo is boosting. That way I can run smaller main injectors with quicker response and have a lot of petrol spraying when the turbo kicks in.

Thanks for sharing with us Martin a welcome to our forum

Brilliant idea, just a pity it is so expensive.

Its the Rand/Pound exchange rate killing us.

So will a Mr Turbo EFI work on something like this? i have one lying around

Not 100% with you. What have you got lying around the weber retroject?

Not sure how it works if they say you can add ANY aftermarket ECU. Maybe they have different wiring kits for different aftermarket ECUs

The critical dimensions are identical including positioning of throttle lever and throttle rotation, so it will be possible to remove a Weber twin choke carb., bolt on Retroject, add any aftermarket ECU and loom and a high pressure fuel supply from a Webcon WFP600.

All the ECU does is take various sensor inputs and work out optimal fueling and timing. Most of these aftermarket ECU's have multiple config options, so if the EFI carb has an option to drive 1 or 2 injectors(depending on the EFI carb's injector count), then it should work fine. That being said, I've seen a few guys toss Mr Turbo ECU's out due to problems.

Did anyone install one of these yet?

I want to install one on my old Datsun L28 engine, but it still have an old points distributor.

The guys at Webcon said I can look at a MicroSquirt management system as it is simple and cheap and can get signal from the coil's + and -, but I checked their site out and it seems like not THAT easy.
On the L28 you must cut diodes from the pc, brige certain points, solder in a resistor, etc. https://www.diyautotune.com/support/tec ... 0zx-turbo/

If I import a retroject for my Dustbin I want to import some extras because there are plenty a Hilux, Datsun, Essex, etc which can run these. But seems like finding an ECU solution is more important than getting the merchandise landed. If we do not have a ECU we cannot use the retroject.

Pieter ek dink jy moet met Louis Zanoli praat. Glo hy het al baie dizzy's moes modify vir sy dictator Efi conversions.

Dankie Cassie

Aftermarket ECU's normally should work with most EFi systems...basics remain the same.

Main thing is to get some specs on the injectors ito impedance & voltage and the check with Spitronics or Dicktator what the tolerances are. I'm more inclined towards the Spits these days...it has on-board coil drivers so one would just have to check if the existing coil is compatible and as far the dizzy goes one could have it gutted and either magnetic/optic pickups installed at an auto-electrical shop.
I prefer optic, no adaptors needed; and with the Spits no TP100 or ignitor required...less complicated wiring & less points of failure, but that's me.

Thank you Steff
I already installed one of those magentic pic ups for the distributor, replacing the points.

I asked the guys from Dictator and they replied
"A Dicktator std will work Fuel only with this setup."

Isn't Dictator less complicated than spitronics?
I have no experience in these, seems like you do.

I have a Dicktator on the SFA and a Spitronics I bought recently but haven't installed yet.
The Spitronics is somewhat simpler in my opinion with the coil drivers on board, so no TP100 or ignitor to be wired manually.

The fuel only setup refers to the ECU running the injectors only, and not the coils. One would still need a crank sensor or dizzy pickup though which could be magnetic or optic. My preference of the latter is because an optic gives a square wave without having to use an interface board, one less point of failure.

If you have already modified the dizzy you might as well let the ECU control the ignition as well. I can't see why it can't be done.

I imported a 38/38 Retrojet for my L28 . Haven't fitted it yet, but I did get 2x extra which I now have stock at our Vredenburg store.

I did not get the wire harness, the price was a bit crazy. You will need a basic Dictator to run it.

Available at:
https://4x4direct.co.za/online-only/942 ... -body.html