EFI/Individual throttle bodies on old renaults

[3006882]

I went for the Jenvey ITB EFI set up, mainly because I already had the manifold for the twin webers for it to bolt straight up to, so it made it the easiest and least painfully expensive option. Though when you start to add up the itbs, ecu, fuel lines, pumps, regulators, idle control, crank trigger, and cam trigger its still quite painful.

 

[Aln]

Hi ReidarUF
Good looking things and probably a good unit for your engine, and lots of other smaller engines too.
However I am puzzled by the second butterflies. They look like a choke in a carby !! Not usually necessary on EFI. What are they for in the original bike application ?
Jaahn

I have the same set up on my injected Suzuki SV650S. The main butterflies are operated via the throttle and cable, the others are operated by the ECU similar to a drive by wire system. I expect this is to control the rate of airflow change to perhaps produce a nicer torque band and smoother acceleration. Seems to work OK.

 

[ReidarUF]

I havent paied much attention to the second butterfly setup but I think Alan Moore sums it up pretty good. The gsxr itbs I used on my Pug 106 also had them but I just removed them and plugged the holes.

What is interresting is the system to make them work in conjunktion with the main butterflies. There is a cam lobe on the second butterfly axle that works against an adjustable arm on the axle on the main butterfly axle. I think this adjustment can be made into a balance adjustment between the two bodies.


@3006882: Your setup looks good. Sometimes the dcoe bodies are just perfect. But I think you make it seem a bit complicated. Cam trigger is not really needed when running wasted spark and batch fire the injectors. And my 106 was idling nicely without any idle control other than some tweeks in the software.

 

[c.lees]

This has got me thinking, maybe my K4M needs ITBs. It will actually make the manifold easier to make, I'm thinking GSXR600 ITBs, 38mm with 80mm spacing. They are in pairs so the centre space could be made 90mm to account for the 85mm post spacing of the head and have a slight kick in the intake runners of 2.5mm. I haven't made any manifolds yet so its an option.

They are cheap as well, including injectors they are around $200. From what I've read the injectors are more then sufficient. I nice way to get a small power increase as well as looking really cool.

 

[ReidarUF]

@c.lees: I would deffinately convert to itb. And the paired gsxr ones should be a good choice. Sandy Brown in England have made a really nice setup for the Peugeot 106 16v/gti. He is using 1000/750 bodies but the 600 are basicly the same. The spacing on the pug is 90mm but as you see he have avoided spacing the bodies. I know from experience there is good reasons for that...

 

[c.lees]

@c.lees: I would deffinately convert to itb. And the paired gsxr ones should be a good choice. Sandy Brown in England have made a really nice setup for the Peugeot 106 16v/gti. He is using 1000/750 bodies but the 600 are basicly the same. The spacing on the pug is 90mm but as you see he have avoided spacing the bodies. I know from experience there is good reasons for that...
View attachment 104114

That is an interesting setup, do you know how they throttle bodies have been connected to the tubes? The only ones I've seen so har use silicon tubes to connect them as that is how they are connected on the bike.

 

[ReidarUF]

On the GSXR there is actually a rubber coupler/inlet with a vulcanised metal flange that is bolted to the cylinder head.

There is a grove on the "tube" on the bodies for this coupler to not to slide off. On theese kits this groove is used as an O-ring groove. Its not perfect as such but seem to seal good enough in the holes in the flange. There is also small metal brackets that secures the bodies to the flange.

I bought one of theese inlets second hand as I thought it was better than my own setup but I sold the car and inlet before fitting it. Anyway I plan to rob this design for another engine later.

 

[3006882]

I havent paied much attention to the second butterfly setup but I think Alan Moore sums it up pretty good. The gsxr itbs I used on my Pug 106 also had them but I just removed them and plugged the holes.

What is interresting is the system to make them work in conjunktion with the main butterflies. There is a cam lobe on the second butterfly axle that works against an adjustable arm on the axle on the main butterfly axle. I think this adjustment can be made into a balance adjustment between the two bodies.
View attachment 104045

@3006882: Your setup looks good. Sometimes the dcoe bodies are just perfect. But I think you make it seem a bit complicated. Cam trigger is not really needed when running wasted spark and batch fire the injectors. And my 106 was idling nicely without any idle control other than some tweeks in the software.

Well I'm certain I've made it more complicated than it needed to be, but I was partially doing it to teach myself EFI tuning, so I wanted sequential injection and ignition. The cam trigger turned out to be a fairly easy fix using an off the shelf aftermarket cam trigger unit from the US made for an air cooled VW EFI conversion that replaces the distributor and making a new shaft for it.
I also have long term visions of a small twin scroll turbo on it, so the extra tuneability can't hurt.

 

[Reidar]

Working on the pattern for the inlet manifolds.

After adding some bondo and details

 

[Reidar]

Big step today as I did my first green sand casting. Pretty good I think but adjustments is needed to the sentre distance of the cores. Shrinkage was less than I though so the core tabs on the model is a bit too far apart. Also I´m not sure of the "trademark" RF. My full initials is RUF but thats allready taken. I´m thinking of RF8

 

[schlitzaugen]

Hey, not too shabby. Are you going FI?

 

[Godzilla]

What are you using for your core material?
Heres a manifold I made for my Simca 1000 a few years ago.

 

[Reidar]

@sclitzaugen: Yes, EFI. Not sure what system to use yet. I have an old South African one on the shelf but there is a new Sweedish system that looks promising. Maxxecu mini.

@Godzilla@Allmost identical project as mine but yours seems more elegant. Any pictures of it finished?
My cores is paving sand with sodium silicate. I suspect yours is the same? And nice core box. Mine is a lengt of pvc pipe split in two.

 

[Bowie]

you guys forging your own parts.. Fantastic!

 

[schlitzaugen]

you guys forging your own parts.. Fantastic!

Casting.

Forging is a bit beyond the home workshop:

https://www.youtube.com/watch?v=Bzhi4kRBNHU

 

[Godzilla]

Sorry, I missed your reply. Yes, sodium silicate is what I used.
I wish I could say my molds were hand made, but I carved them on my cnc router.

@sclitzaugen: Yes, EFI. Not sure what system to use yet. I have an old South African one on the shelf but there is a new Sweedish system that looks promising. Maxxecu mini.

@Godzilla@Allmost identical project as mine but yours seems more elegant. Any pictures of it finished?
My cores is paving sand with sodium silicate. I suspect yours is the same? And nice core box. Mine is a lengt of pvc pipe split in two.

 

[Reidar]

@Godzilla: Real nice! Seems like you made your own throttlebodies too?

 

[schlitzaugen]

If you have a CNC router, why not make the manifold itself on it?

 

[Godzilla]

I made the cnc router in college as a means to make casting patterns and cut sheet goods. As such, it wasn't very stiff and couldnt cut alu very well.




Later, I did get an old Tape-drive Hurco KMB-1 mill and converted it to run on windows.



I used that machine to make a manifold for a souped up Fiat a buddy has. It used a single throat of an IDF Weber.

 

[Sunroof]

Love home made workshop equipment, your a clever guy. But I guess the professional machine does it better or would that be easier?