dave88sw

Megasquirt Series

39 posts in this topic

Not sure if it's been mentioned but there's extruded ali fuel rail by the foot and injector-hole shaped drill bits available (they form a complete injector seat shape) from places like Summit Racing, you'd likely find all manner of solutions on the MS forums where people are squirting lumps that don't have native EFI gear available.

You could also just machine a spacer, either as one lump or 2 or 4 smaller lumps, to go between manifold & block and accept one injector per port.

If you do the DIY-TBI style suggestion then you may need more than one injector but that shouldn't be hard. As TSD says, you size your injectors by power rather than engine capacity so there's any number of popular cars & even motorbikes you can raid for parts.

I really want to see someone squirt a 2.25p, it's long overdue!

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Thanks everyone for the replies.  I have had a good look over trigger wheels site to see what was available, lots of very useful stuff.  My issue with drilling the manifold for injectors was simply that the fuel rail would want to occupy the same space as the throttle body, really it's just me being lazy, hoping to use the extruded section fuel rail that trigger wheels sell but i guess i could shape one up myself to clear.  The only other thing was the servo take off would be in the way of number 4 injector but i could redrill that elsewhere.

Really i just can't make my mind up between full multipoint, which would involve removing the manifold and thus having the car immobile for a while (its parked on a public road which makes that awkward) or single point that would allow me to make something up to be bolted in place of the carb when i'm ready. 

Very good points made about V8 injectors, i made an assumption that as the mpg was similar they must be supplying approx the same amount of fuel but as pointed out, there's 8 rather than 4/2.  Obviously i could use other injectors but it sounds like the general opinion is that it isn't the best method.

I'll keep looking into it :lol:

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If you made up a system using a 200TDI manifold, you could build entirely off vehicle meaning it would reduce down time... Also has servo take off easily accessible, I think? 

You may get it working with 4 RV8 injectors, never know until you try :)

 

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I didn't think the 200 had the same mounting pattern?  I've seen someone alter a 19j turbo set up to fit a 200tdi and it was a lot of work, the 19j as far as i know does share the same inlet/exhaust ports as a 2.25 petrol.  If it does fit, i have a 300tdi manifold here (which is much the same as a 200).  Would i not have issues mounting the injectors 45 degrees to the ports though as the intake runners slope down.  The servo outlet would be a vacuum pump on a 200 though, although that's an option as i could remove the dizzy and install a 200 vacuum pump meaning i could lose the servo take off all together.

I do have a set of 1.8 k series injectors too, when i get to the point of mounting injectors i'll see what i can get hold of that works best, as long as they're readily available i'll be happy.

Thanks

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Ah I was under the impression they were the same pattern?

If not then you are a little more limited, but still possible with an earlier inlet.

For injector positioning, you would have to mock it up, there's no second guessing this stuff I'm afraid!

For a servo stake off, just get your mate to weld a bung into whatever inlet you choose - the 200TDI one has a gland centre of the plenum from what I could see, so that would make it easy! The thought of installing the notoriously unreliable vacuum pump instead of just getting a bung welded into an inlet baffles me frankly :)

There's no two ways about it, whatever you do do, it will involve some fabrication, with some thought though, you can minimise down time :)

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I think the diesel manifolds have a connection for the exhaust of the vacuum pump, which can of course be used as a takeoff for vacuum when in petrol configuration. Don't forget that the only reason you have a vacuum pump on a diesel is because there's no throttle plate, and hence no real manifold to speak of. I believe they're interchangeable with a little fettling. 

Fridge's suggestion of a plate that sits between the manifold and head to mount injectors in certainly has some major merits. I'll even offer to CAD one up for you! Laser or CNC isn't as expensive as you might think.. The only slight sticking point might be that stupid arrangement where the exhaust and inlet manifolds share bolts, but this can be overcome with a little thought. The plate will give you space to angle the injectors, and you can use the carb as a simple throttle butterfly with its fuel supply disconnected. The TPS will need a little thought if going this route, of course. 

Cheers

Ian 

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Ref trigger wheels, I might have a few random shapes/sizes knocking around (either that or I gave them to Nige @ Megasquirt V8), I'll try and have a dig in the shed.

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I have a 100mm one here if it is any good... Probably rather small but you never know :)

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A 300tdi manifold doesn't seem to line up with the 2.25 petrol manifold gasket i have kicking about so unfortunately i think that's a no go.

The more i look at the petrol manifold the more i tell myself i'm being stupid, trying to avoid a bit of work with the fuel rail makes so much more work elsewhere i ought to just suck it up and crack on with the petrol manifold. It does seem to lend itself quite well looking at it.

Very good point with the vacuum pump, it's unnecessary when the manifold can provide the vacuum with no moving parts.  I just thought it would be nice to do away with the redundant distributor altogether haha.

I do like the idea of an adaptor to go between manifold and head as it's removable but i think it would be easier to weld in injector bungs from trigger wheels and just put in the work making up the fuel rail.

I appreciate the offers of trigger wheels, i'll measure the crank pulley when i get chance and get back to you.

I've been looking for a spare inlet manifold for months with no luck on ebay, just posted in the wanted section on here but not holding out much hope.  What are peoples thoughts on going back to series manifolds? They're a little smaller and take a smaller exhaust if i were to change back (currently has 2.5" steve parker kit) but they're much more readily available and i'm not sure what benefits the bigger manifolds give (i was certainly disappointed when i changed over to the twin choke webber set up, the gains were barely noticeable).

Thanks

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What's the issue with the redundant dizzy? You could "stubby" it like Nige does so it's still driving the oil pump if that's all it's doing...

I wouldn't worry about the bigger manifolds, it's hardly an F1 lump, the benefit you'd get from EFI & decent ignition would blow any small loss into the weeds.

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There's no issue really, i just hate the thing so much (constant issues with rotor arms and caps) i'd love to throw it in the scrap but it can stay to fill the hole or stubby it as you say.
That's my thinking too, i might go down that route if no later manifolds show up, i know someone who has some series manifolds going begging.

Thanks

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Do as TSD did - bundle the old HT leads up above the dizzy and cut them all off about 3" long, will confuse everyone who looks under the bonnet with it still running!

For extra badness, leave the coil installed on the wing.

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Or better still, put the coil on the rocker cover, even more visible...

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