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motor swaps

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Old 03-26-09, 04:15 PM
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motor swaps

so i jsut bought a 88 gtu for 400 bucks. the guy had it running about a week ago and then it just stopped working. after getting it home i went to the local junk yard because a friend of a friend took his '90 rx7 there and it ran before he took it there. i talked to the guy that runs thae show and he told me if i pull the motor i can have it for 100 bucks. most likely cheaper tho. now i want to know is this a possible motor swap or would it be difficult. like would i have to swap wiring harnesses and ecus? and both are non turbo. any response will be greatly appreciated!!! thanks
Old 03-26-09, 05:40 PM
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Swap in the S5 short block (minus the front cover) and the S5 intake manifold. The S4 throttle body will need to be modified slightly to fit the S5 manifold, and you will need to set up a mechanical or electric means of activating the S5's VDI. All electronic parts need to stay S4.

http://www.rotaryresurrection.com/2n...o_s4_swap.html
Old 03-26-09, 10:20 PM
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ok so what kind og modifcations need to be done to teh throttle body to make it fit on the s5 manifold?
Old 03-26-09, 10:40 PM
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I think he means you have to rig the manual OMP from the s4 to work with the electric OMP from an s5. The s4's use a metal rod to tie the throttle body and the OMP together to control oil flow under acceleration.

Couldn't he just "wire" the s4 OMP wide open, or are there harmful effects of that?
Old 03-26-09, 11:03 PM
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so is it possible to use the electric omp off the s5 or would i have to use the manual one? like i couldnt possibly wire it in somehow?
Old 03-26-09, 11:57 PM
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I'm pretty sure that would require an s5 engine harness and ECU, in other words, too much BS. Anything's possible, though.
Old 03-27-09, 12:07 AM
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i couldnt wire it up to a toggle switch or to the ignition. like bypass using a stock wiring harness and ecu. just run my own wires.
Old 03-27-09, 04:30 AM
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Simplest work around is to block off the MOP and pre-mix, use the S4 intake, ecu, wiring, etc.. You will need the S5 flywheel to maintain engine balance.
Old 03-27-09, 11:39 AM
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Originally Posted by thejallenator
so is it possible to use the electric omp off the s5 or would i have to use the manual one? like i couldnt possibly wire it in somehow?
Originally Posted by RotaryRocket88
...All electronic parts need to stay S4....
No, you can't use the electronic S5 OMP with the S4 ecu / wiring. You wouldn't want to anyway, since they're prone to failure. You will want to use the s4 front cover and s4 omp (or premix instead).

The S4 TB only has to have a little metal ground off the bottom to clear the VDI chamber on the S5 intake manifold. Search "S5 manifold swap" for details.
Old 03-27-09, 03:06 PM
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basically the easiest thing i could do it just buy this http://www.pineappleracing.com/index...ROD&ProdID=103 and just add 2 stroke everytime i fill up my car? and is there a certain gas to 2 stroke ratio i shoulc use?
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