SumDarkPlace Posted October 24, 2016 Share Posted October 24, 2016 New to this forum. We've picked up a 1986 90 that has been converted to V8. Not sure of the history of the engine, but is running terribly on a flapper efi. Compression seems good and even, and once running it's smooth and powerful. I've found a complete Thor top end, so I'm putting the bits together for a sequential fuel and spark MS3X build. It might be overkill, but I'm planning long term, it won't stay 3,5 forever What problems am I likely to run into mating the Thor to the 3.5? I'm going to use an electric water pump and controller, to reduce losses (but mostly because I found one cheap!) I'm new to the RV8 and MS, but I've worked with a lot of jap performance engines and mappable ecus in the past. Thanks in advance. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted October 25, 2016 Share Posted October 25, 2016 MS3 is massively overkill and complex too. MS1 is all thats needed.... Thor Top end fits onto a 3.5 no real issues, Fuel ump will be needed, in tank RR ones are good as cheap relaible, your need all the othjer normal MS Stuff, but also some bits for the thor itself, including PRV etcas the ecu controls the pump on thor, also swapping out the CTS. HAve a lookie at www.megasquirt-v8.co.uk Any questions ask, I am sure others will add to the questions asked Nige Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted October 25, 2016 Share Posted October 25, 2016 Have to say I enjoy doing a microsquirt installation if not doing anything special. I would also go with MS3 if I was doing one of my own trucks now... Just for future support. Quote Link to comment Share on other sites More sharing options...
Quagmire Posted October 25, 2016 Share Posted October 25, 2016 I have ms2 on my p6, ms1 on my 90. I have to say I prefer ms2 even if it just means I can drive the factory idle stepper, some of the other features are handy too (incorporate afr, the clt/mat correction table etc...). As Bowie says, support going forward is something that should be considered too. If the OP wants to go sequential then they will need ms3. I'd suggest having a read of the feature comparison tables here: http://www.msextra.com/feature-xref.html And figuring out what is required, what is nice to have, what the budget is and then go from there. Have fun! Quote Link to comment Share on other sites More sharing options...
dangerous doug Posted October 25, 2016 Share Posted October 25, 2016 If your buying the top end make sure you get the push fitting that feeds the fuel rail and the rocker covers. The breathers are in different places on the inlet manifold and the oil fill is on the other side and a lot taller Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted October 25, 2016 Share Posted October 25, 2016 I think the oil fillers unscrew from the rockers Quote Link to comment Share on other sites More sharing options...
dangerous doug Posted October 25, 2016 Share Posted October 25, 2016 They do yes but then you have a flame trap under the throttle body. I also tries using 2 left bank ones but that didn't work out nicely either. Maby I'm just fussy. Quote Link to comment Share on other sites More sharing options...
SumDarkPlace Posted October 25, 2016 Author Share Posted October 25, 2016 5 hours ago, Hybrid_From_Hell said: MS3 is massively overkill and complex too. MS1 is all thats needed.... Thanks Nige I'm deliberately going over complex, as I'm intending to go sequential. The 3.5 is effectively a testbed to learn the MS, and what I can do with it. A different block will come in the future, once I have got the hang of things. Quote Link to comment Share on other sites More sharing options...
SumDarkPlace Posted October 25, 2016 Author Share Posted October 25, 2016 2 hours ago, dangerous doug said: If your buying the top end make sure you get the push fitting that feeds the fuel rail and the rocker covers. The breathers are in different places on the inlet manifold and the oil fill is on the other side and a lot taller Thanks, good to know! I suspect I'll be fabricating a lot of pipework anyway Quote Link to comment Share on other sites More sharing options...
SumDarkPlace Posted October 25, 2016 Author Share Posted October 25, 2016 5 hours ago, Quagmire said: I have ms2 on my p6, ms1 on my 90. I have to say I prefer ms2 even if it just means I can drive the factory idle stepper, some of the other features are handy too (incorporate afr, the clt/mat correction table etc...). As Bowie says, support going forward is something that should be considered too. If the OP wants to go sequential then they will need ms3. I'd suggest having a read of the feature comparison tables here: http://www.msextra.com/feature-xref.html And figuring out what is required, what is nice to have, what the budget is and then go from there. Have fun! Definitely planning sequential, and COPs. Never liked the idea of batch fire and wasted spark, it seems so wasteful! Quote Link to comment Share on other sites More sharing options...
SumDarkPlace Posted October 25, 2016 Author Share Posted October 25, 2016 The previous owner fitted a walbro uprated fuel pump during the diesel>petrol conversion, so I'll try running with that initially. As long as it has the legs to keep the pressure there at top end Quote Link to comment Share on other sites More sharing options...
elbekko Posted October 26, 2016 Share Posted October 26, 2016 If you're using the Bosch/Thor injectors, you'll need 3.5 bar of fuel pressure, not the 2.5ish the flapper runs at. So make sure the pump can actually handle that. Quote Link to comment Share on other sites More sharing options...
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