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13b-msp motor in a FB with 2nd gen EFI

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Old 10-30-15, 02:44 PM
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NV 13b-msp motor in a FB with 2nd gen EFI

Back in the First gen game and it been years. I picked up a GSLSE that someone had modded back in the days and then started taken it apart. It had a carb on it and that is long gone. Motor seems oky and has decent compression 80ish I believe. Anyways I have a rx8 and was checking CL and found a smoking deal a completed rx8 motor with wiring ecu and pedals. The rx8 computer requires way to much to run properly in another car. I really picked it up as a spare for my 8 but I have be pondering about slamming it into a first gen just to have something different. Racing beat makes an intake adapter that allows you to bolt a 6 port 2nd gen manifold on the motor. Its really designed for a carb set up but the stock fuel injection should also fit.

Rx8 6 port short block
GSLSE front cover and dizzy with drive gear
2nd gen water pump??????
auto rx8 counter weight
light flywheel ??????
GSLSE stock trans


So what you guys think go EFI with electronics from a s4, s5, or something else or Carb(Weber or Holley)
Old 10-30-15, 04:08 PM
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interesting, its possible. i think i would use the Rx8 intakes, as they are better. the Rx7 injectors would drop right in, if you used the S5 ecu, it would run the VDI, and could possibly run the 6pi, although its solenoid output to motor, so something needs to be done there.

that all being said, not sure that the timing or fuel is right for a 230hp engine
Old 10-30-15, 05:40 PM
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Custom intake, twin Nikki carbs.
Old 10-30-15, 07:51 PM
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Originally Posted by Cookboy
Custom intake, twin Nikki carbs.
I've been waiting for someone to say twin nikki's. 20B with a twin nikki manifold that's what I wanna see.

Waaaay ot.
Old 10-30-15, 08:04 PM
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Originally Posted by Cookboy
Custom intake, twin Nikki carbs.
I actually mocked a mani for 2 nikkis up this summer. The linkage would be complicated, and they take up a lot of room. Also, just the carb is 5 and 3/4 high, so fabbing an air cleaner to feed both of them is a tight squeeze in the FB. Especially if you have a strut tower bar like I did when I was playing with the cardboard mock ups.
Old 10-30-15, 08:14 PM
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Originally Posted by wankel=awesome
I actually mocked a mani for 2 nikkis up this summer. The linkage would be complicated, and they take up a lot of room. Also, just the carb is 5 and 3/4 high, so fabbing an air cleaner to feed both of them is a tight squeeze in the FB. Especially if you have a strut tower bar like I did when I was playing with the cardboard mock ups.
Do it split cable like a motorcycle. But you'd have to keep all the ports mixed. I dunno, just thought it would be real cool to see.



EDIT: If done, it would be a pure aesthetic thing... Hot rodish.

Last edited by Qingdao; 10-30-15 at 08:18 PM.
Old 10-30-15, 09:31 PM
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Originally Posted by wankel=awesome
I actually mocked a mani for 2 nikkis up this summer. The linkage would be complicated, and they take up a lot of room. Also, just the carb is 5 and 3/4 high, so fabbing an air cleaner to feed both of them is a tight squeeze in the FB. Especially if you have a strut tower bar like I did when I was playing with the cardboard mock ups.
2 of these.

13b-msp motor in a FB with 2nd gen EFI-image-1777725499.jpg
Old 10-30-15, 09:37 PM
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i think most of us can agree it's not an ideal situation, but a S5 ECU sounds interesting enough. it definitely sounds worth a try since you already have the car and the engine.
Old 10-30-15, 10:03 PM
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Originally Posted by diabolical1
i think most of us can agree it's not an ideal situation, but a S5 ECU sounds interesting enough. it definitely sounds worth a try since you already have the car and the engine.
OK so I'll keep an eye out for s5 wiring and ecu. Yea the rx8 intake is much better but did know how tb would work out and the tps as well
Old 10-30-15, 10:05 PM
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Originally Posted by 9bobo9
OK so I'll keep an eye out for s5 wiring and ecu. Yea the rx8 intake is much better but did know how tb would work out and the tps as well
Also anyone have a s5 wiring diagrams?
Old 10-31-15, 08:49 AM
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If it's a series 1 renesis it has 6 injectors you would need to control. You also need to figure out the throttle and all the actuators. Renesis had electronic throttle with a single blade.

Renesis has a 5 stage induction system, with electronic throttle and independent control of secondary and aux ports. Then it had VDI and a variable length induction pipe to the airbox. It is Porsche or Ferrari level of complexity.
Old 10-31-15, 03:44 PM
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rx8 info

Originally Posted by arghx
If it's a series 1 renesis it has 6 injectors you would need to control. You also need to figure out the throttle and all the actuators. Renesis had electronic throttle with a single blade.

Renesis has a 5 stage induction system, with electronic throttle and independent control of secondary and aux ports. Then it had VDI and a variable length induction pipe to the airbox. It is Porsche or Ferrari level of complexity.
Yea that's my main reasoning for deleted the rx8 electronics and intake. I under stand the complexity and have most of the wiring and pedal. I just want something a little easier to manage so 2nd Gen efi seems more viable but I could just throw a weber on it and run a gslse dizzy and be done
Old 10-31-15, 04:13 PM
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you could probably situate and fix the secondary port sleeves in the open position and create a delayed secondary butterfly for the secondaries based off an FC intake manifold if the adapter truly fits the MSP and adapts to an FC UIM.

aside from that, i really don't see why it wouldn't work. however i doubt you will even reach stock MSP power levels even with a free flowing exhaust system. mainly due to ECU tuning variables and the lacking tuned MSP HP intake. but is it worth it? if you can manage to tweak it to optimize the stock ECU via piggybacks or hacks, i do think so. just keep in mind, the MSP series 1 has the worst track record for longevity of any rotary since the early 70's, if you can rebuild it then that will eliminate costly overhauls if you plan to drive it alot or race it. even stock non abused cars wear out the rotor housings in less than 100k miles, granted i had a customer with an original 250k mile S1, i honestly have no clue how he got that lucky to have it go for so long.

Last edited by RotaryEvolution; 10-31-15 at 04:18 PM.
Old 10-31-15, 11:25 PM
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Wow 250k that's crazy. I use to work for mazda as a mechanic years ago. I swapped rx8 motors out like weekly. Almost all were auto 04 cars with low compression.
Old 11-01-15, 06:14 AM
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the S1 4 port auto is horrible, i won't even buy one to flip because they are engine killers.
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