missingsid Posted October 15, 2009 Share Posted October 15, 2009 OK so the title rules out half the members here I tried to ask one of the exulted ones but it seems that he has an issue with a gearbox. Will a P38 4.0 EFI manifold and Plenum work on a 3.5 with Megasquirt? I have looked at the MS topic and it looks like all the later injectors are the same so it comes down to the air flow rate. Will it flow too much air to be set up correctly? Can the panel please advise Cheers, Marc. Quote Link to comment Share on other sites More sharing options...
Aragorn Posted October 15, 2009 Share Posted October 15, 2009 I suspect it will be fine. If the manifold runners are larger than the 3.5 equivalent you'll probably shift the power up the rev range a bit, but i cant see it being a problem and i doubt theres much difference in the runners anyway. Quote Link to comment Share on other sites More sharing options...
steve_d Posted October 15, 2009 Share Posted October 15, 2009 See no reason why not. It will only breath as much as it needs which begs the next question Why not fit a whole 4.0 and not just the top bits? You know you want to. Steve Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 15, 2009 Share Posted October 15, 2009 As long as you can sort the plumbing, yes no reason it won't work. Didn't they have a returnless fuel line or something? Quote Link to comment Share on other sites More sharing options...
missingsid Posted October 15, 2009 Author Share Posted October 15, 2009 Ah, So a slightly different fuel system that might me an issue? thanks for the quick replies. Marc. Quote Link to comment Share on other sites More sharing options...
missingsid Posted October 15, 2009 Author Share Posted October 15, 2009 See no reason why not. It will only breath as much as it needs which begs the next question Why not fit a whole 4.0 and not just the top bits? You know you want to. Steve Top bit £25. Whole bit £xxxxx Quote Link to comment Share on other sites More sharing options...
Dave W Posted October 15, 2009 Share Posted October 15, 2009 The only problem I can think of would be the clearance (or lack of) for the distributor. Obviously you don't need the distributor as such for the ignition if you go MS but you do need something to drive the oil pump. You'll need to supply a fuel pressure regulator (an adjustable after market one like the Mallory one) as the Thor doesn't have a regulator on the manifold (or a return) but uses a regulator at the pump instead. This isn't a bad thing though as it will allow you to adjust the pressure to suit your engine/fuel requirements/injectors. Quote Link to comment Share on other sites More sharing options...
missingsid Posted October 15, 2009 Author Share Posted October 15, 2009 Thanks, You have matched one of my thoughts. The other is a bit of a concern but hopefully MS and a lower Dizzy for the oil pump drive. Marc. Quote Link to comment Share on other sites More sharing options...
LittleBlue88 Posted October 15, 2009 Share Posted October 15, 2009 Am i right in thinking the Thor-type manifold doesnt have a thermostat housing? Quote Link to comment Share on other sites More sharing options...
missingsid Posted October 15, 2009 Author Share Posted October 15, 2009 I am looking at an early P38 manifold GEMS not Thor. I would love a Thor but I have never seen one yet. Cheers, Marc. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 15, 2009 Share Posted October 15, 2009 Early P38 manifold gains you nothing whatsoever over the earlier stuff - it's basically the same. Throttle mouth is the same diameter etc. etc. it's just a few drillings and ancillaries that are different. Only worthwhile thing is going from flapper to hotwire which gets you clamp-down type injectors and loses the injector resistor pack (high impedance injectors). Quote Link to comment Share on other sites More sharing options...
Dave W Posted October 15, 2009 Share Posted October 15, 2009 I am looking at an early P38 manifold GEMS not Thor. I would love a Thor but I have never seen one yet. Cheers, Marc. You fooled us with the 4.0, as above, no benefit really in changing to a GEMS manifold. Thor manifolds are available, I've seen a few come up - I have one in the garage somewhere. Quote Link to comment Share on other sites More sharing options...
missingsid Posted October 16, 2009 Author Share Posted October 16, 2009 Sorry about the confusion. I wanted an EFI for Megasquirt and this came up cheep so I wanted to get it but needed help. This information is even better as I could not side to side it with an old one. It is interesting that the throttle mouth looks bigger until you compare it. Main reason for going with this one was cost and the fact that it was newer than the other ones for sale so I expect less wear on the throttle spindle? Actually it looks more compact (a bit). Fridge, I didn't know that you had lots of manifolds! If this has high impedance injectors then this could potentially work with Microsquirt? I know you are not keen on it but it is waterproof and small so it seems a good idea if it can handle the power. Do you have any EDIS-8s for sale as I am after one Thanks for the great information so far. Marc. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted October 16, 2009 Share Posted October 16, 2009 As long as you can sort the plumbing, yes no reason it won't work. Didn't they have a returnless fuel line or something? GEMS doesn't, well at least the one in my garage has a regular return just like the hotwire setup. Am i right in thinking the Thor-type manifold doesnt have a thermostat housing? Neither does RR GEMS system, the thermostat is a plastic housing that sits in the bottom hose -think it is the same/similar in a 300TDI. I'm putting together a GEMS 4.0 setup to go in my RR, converting from the hotwire setup on my dead 3.9, so when I'm done I'll let you know of any wiring differences. Quote Link to comment Share on other sites More sharing options...
lansalot Posted October 16, 2009 Share Posted October 16, 2009 You can get EDIS8s cheap from http://www.trigger-wheels.com/ Quote Link to comment Share on other sites More sharing options...
Dave W Posted October 16, 2009 Share Posted October 16, 2009 The flapper 3.5 Plenum/manifold is easier to MegaSquirt than the hotwire because the idle control is built in and you don't need to worry about it. You could use the injectors from the GEMS manifold if the flapper injectors are low impedance but MS will work happily with both anyway. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 16, 2009 Share Posted October 16, 2009 Fridge, I didn't know that you had lots of manifolds! If this has high impedance injectors then this could potentially work with Microsquirt? I know you are not keen on it but it is waterproof and small so it seems a good idea if it can handle the power. My doubts about MicroSquirt are based on using high impedance injectors - it definitely can't handle 8 low impedance ones, and even high impedance is borderline. Why do you need your ECU to work underwater unless you're bolting it under the car? Wires can be moved, my ECU is above my head so if it gets wet I've got bigger problems. TBH once the PCB is conformally coated they'll handle the odd dunk anyway - ask Rog! The microsquirt also needs the MAP sensor mounted externally. My setup is 3.5 top end with 3.9 injectors & fuel rail, and will be getting a PWM idle valve. The flapper one is fit-and-forget but you then have none of the idle stabilisation / stall prevention that you get from the ECU controlled one. No I don't have any EDIS-8's for sale at the moment, check my sig Quote Link to comment Share on other sites More sharing options...
missingsid Posted October 19, 2009 Author Share Posted October 19, 2009 Thanks all for the help. See you all soon on the Megasquirt topics Marc. Quote Link to comment Share on other sites More sharing options...
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