Well, tried something a bit different today!
Took the balance pipe, between the intakes, off and replaced it with two fuel injectors, plumbed into the high pressure fuel system (that is now controlled by the Megasquirt ECU). The throttle linkages and return springs were removed from the carbs and the throttles were jammed open.
The existing air plenum had a BMW throttle body fitted onto it:
With some MASSIVELY dodgy wiring (I'm using domestic screw terminal blocks to make things easier before it's all in place and ready to be crimped/waterproofed), got the TPS, IAT and CHT rigged up (CHT is measured using a EPCOS B57560G103F thermistor, JB Welded into a brass fitting that is bolted behind the Cyl #4 bolt):
Pressed the button and to my surprise, it fired up! With a bit of fiddling with the laptop, actually got it idling pretty well at one stage, although did have a massive cloud of oily smoke coming from the exhaust on one occasion. The great thing is that you can hear the ECU trying to stop the engine stalling and it idles much better than it did on the carbs (from cold, anyway).
Of course, I have a lot of tuning to do (haven't got round to fitting the proper carb replacements yet) but it's an encouraging start and once I've rigged up a throttle linkage, I should at least be able to move her around in the front yard
MegaSquirt EFI install
Re: MegaSquirt EFI install
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Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Re: MegaSquirt EFI install
Just drill a spot face (with a larger drill bit) perpendicular to the face using a 90 deg tipped drill bit. You now have a flat 45 degree surface on which to start your angle drilled hole.drilling an angled hole through an angled face
'76 710K
Re: MegaSquirt EFI install
That's a superb tip! Just trying to pin down my tame welder...
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Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Re: MegaSquirt EFI install
Just had contact from tame welder and he's finished sticking my bits together:
These are the boxes that will be replacing the carbs but retaining the top air plenum
Going to collect them later this week so I can really make some progress now! Have been a bit slack with all the rain we've had as not really conducive to working on the car without cover.
These are the boxes that will be replacing the carbs but retaining the top air plenum
Going to collect them later this week so I can really make some progress now! Have been a bit slack with all the rain we've had as not really conducive to working on the car without cover.
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Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Re: MegaSquirt EFI install
Bolted in place (with some tape over the inlet holes to stop bolts etc. dropping into the engine):
Injectors trial fitted but not decided how to secure them yet...
Injectors trial fitted but not decided how to secure them yet...
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Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
- Jimm391730
- Posts: 1456
- Joined: Wed Apr 14, 2004 10:58 pm
- Location: Idyllwild, CA
Re: MegaSquirt EFI install
How confident are you that you won't have a vacuum leak at the joint to the air plenum?
Jim M.
712W and 710M
712W and 710M
Re: MegaSquirt EFI install
The tops of the injector housings have precision machined round fittings that fit into the original seals (which are brand new, as it happens)Jimm391730 wrote:How confident are you that you won't have a vacuum leak at the joint to the air plenum?
If you mean the flange fitting at the top of the box section then I've yet to fit a seal there. Using the bottle screw I've fitted in place of the eye bolt and cam means I can get much more downwards pressure on the whole assembly - it certainly feels pretty rigid. I might need to wire lock it in place to stop it vibrating free whilst driving but that's not a problem
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Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Re: MegaSquirt EFI install
After a long break, I've finally got my fuel rails back from the welder!
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Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)
Robin
Pinzgauer 710K
MegaJolt ignition
(upgrading to MicroSquirt)