Just been looking on ebay (sober so i haven't bought anything) and i had an idea.
Take an existing carb manifold for a crossflow. Remove carb. make metal plate with hole in it. Add tube to plate. Attach cheap throttle body to
plate.
Can anyone see an issue?
(ok, i need to put the fuel injectors somewhere, i'm thinking about that & wondering can i get away with one or two on the tube just before
the throttle body - which would save me the hassle of trying to figure out how i'd mount them on each intake runner on the ali manifold)
why don't you just make a manifold?
get r1 throttle bodies, the injectors are built in it so you don't need to worry about drilling manifold
[Edited on 20/6/09 by omega0684]
why not just use the carb and drill/tap a hole for the injector(s)?
PS get hold of a copy of Dave Walker's injection book - IIRC there's photos of some twin 40s that have been converted to injection...
hmmmm ....
drill crossflow manifoldto fit injectors and fit carbs for the throttle disc.
or take a tube, drill hole right teh way trought to fit a spindle and disc and fit injector.
i guess it could be done. its basicaly how the original ecotec manifold and TB is... seems a lot of work though
most injectors are a push fit, so some means of holding it inplace, with a fuel rail, would be needed. Injector pockets can be bought of the shelf, so no worries there.
Wet manifold design is significantly different (and more difficult) than dry manifold design.
The further the injectors are away from the head, the greater the headache caused by fuel stuck to the walls of the manifold.
After fighting with bike injectors spaced ~6in from the head, I had some steel rod lathed out to the correct diameter for the injector O-rings, cut
the pipe off at a 30ish degree angle and welded the 4 bungs to the runners next to the head.
Result: throttle response an order of magnitude better than with the bike injectors.
Issue with drilling the manifold is its ali (both the weber one and the ford originial).
This presents two problems,
1) welding in the injector bung
2) positioning the hole accurately
If i could sort these two problems i'd use my webers DCOE's as throttle bodies - but i can't think of a simple, cheap, easy solution. I
can get a car throttle body for a couple of quid on ebay hence got thinking.
what engine?
At the moment its the crossflow .... at some point i'll migrate to the zetec sat in the back of the garage.
Also noticed last night whilst ebaying that the xr3i injection manifold is in two parts - one part looks very like the crossflow manifold!
can't you get a pre made dcoe tb to crossflow manifolds already? i know you can for xe's, and they're not that dear
If its what I'm thinking of you're looking at 500 quid.
I'm trying to do this locost
Something occured to me that I didn't question before ..... i know carbs are better at atomising the fuel - but why is it that much worse having
injectors around the carb position than just having a carb?
(or is it a case of no actual benefit)
Made my manifold to take ZZR1100 T/Bs using an inlet manifold as a template , a piece of 12mm ally plate cut to shape with a wood working coping saw , 4 bits of ally bar (I had it) bored to size, another off cut for the water outlet and got it welded up . Total cost for manifold was about £40 . Don't know if he ever sold it but Paulf had a complete set up for sale a while ago
i've got a set of Blackbird throttle bodies in the attic ..... i just liked this idea as a direct replacement for the existing carb.
Sold mine on ebay some time ago, I made the manifold from 10mm steel plate and 38mm exhaust tubing for the runners.I think theres some pics in my
archives.
If going injection the you may as well do it properly so as to get the full benefit .
Paul.
quote:
Originally posted by MikeR
i've got a set of Blackbird throttle bodies in the attic ..... i just liked this idea as a direct replacement for the existing carb.
You can pick up DCOE manifolds for the crossflow pretty cheap if you keep a look out on eBay and local free ads etc. Then you just need a tatty pair of DCOE carbs; as you are not using them for controlling fuel the condition is not overly important as long as the throttle spindles and bushes are ok. You could even use the old Solex DCOEs that hardly anyone wants.
But the issue then is getting the fuel injectors into the manifold - i can't think of an easy (locost) way of doing it. Dad recons it could be done easy enough with a mill ..... which i don't have and means either begging favours or paying someone.
quote:
Originally posted by MikeR
But the issue then is getting the fuel injectors into the manifold - i can't think of an easy (locost) way of doing it. Dad recons it could be done easy enough with a mill ..... which i don't have and means either begging favours or paying someone.
Jenvey do the injector pockets @£6.30 each.
I did use a pair of Weber 40s with all of the fuel control gubbins removed and the shortened them as throttle boddies. I picked up a Ginnetta plenum
(which had the injector pockets in it) and cut that down and moddified it to take the 40s.