DR_Knight

iTrader: (23)

Been running a s5t2 keg with s5 manifolds and s4 throttle body, s4 engine harness, trek and all that crap. Rewired alternator already for s5. I see it more as a track car and only use headlights, tail lights, signals, radio and speakers, dome light gauge lighting, so basic. Now I need to make this legal and I like my motor so don't feel like getting a s4 keg.

I already know what equipment is needed but now I need the help from the rx7club community to discuss wiring s5t2 ecu to s4na chassis harness.

I have swapped chassis harness before so I can do it again to s5 if need be but if anybody has wiring tips without changing chassis harness, much appreciated.

I already know the basics where most people say it won't work but I'm asking those who have done it. This must be able to pass state ref.

Option 1.
Wire s4na harness to s5t2 ecu
Option 2.
Change chassis harness
Links and other threads much appreciated.

^Zircon248

iTrader: (5)

I've done it, its been a pita but did'nt cost much and thrust me it is time consuming. I did made some plan of wich wire goes where from the S4NA body harness to the S5T2 emission harness but I don't know where those went. Best thing to do is get all the schematics from S4 and S5, do one system at a time and check the routing of every sensor's connectors. So if you go that route plan ahead so you don't mess thing up ! Also, I did get the Rtek 1.5, got rid of the OMP and do premix.

Well you have to understand those schematics before starting to cut down stuff.

So in difficulties order:

1. Swap the electronics from the S4 to work on the S5 engine
2. Swap the body component from the S5 (full S5 conversion)
3. Redo by yourself the wiring and match S5 to S4 (keep in mind that this one does not cost that much and is time consuming but it can be done)

Good luck !

DR_Knight

iTrader: (23)

Yeah figured I'd have to go that route of repinning the harness. Very familiar with the fsm wiring diagrams so not too worried. Guess all I really need this thread for is if someone has the wiring repinning already done. Will be much appreciated

j9fd3s

iTrader: (3)

having just finished an REW to S5 rewire, i think i would just buy an adapter, and then move some wires around, except for that it'll plug in.

GrossPolluter

iTrader: (1)

Now are you going because you want to register your car with the engine swap, or did you get pulled over and now need to make sure everything is legal?

If you got a ticket from an officer to go to the state referee , the engine swap is illegal unless you registered it, then you would need the original engine that came with the car, s4 na, or s5 na. All the smog equipment must be there. I believe in ca you need factory cats or "bolt in ca carb legal cats, none of those weld in 49 state legal cats. air intakes are legal as long as they are 50 state carb approved. Intercooler upgrades are legal. I'm not sure about going from tmic to fmic though.

j9fd3s

iTrader: (3)

my friend used to work at the BAR, and the T2 swap doesn't need to go to the ref, because it was an option in the first place.

although it does need to be the correct series, S4 engine in S4 car, and it does need to have all the emissions parts on it, for the series.

if you do out of series, the S4 engine in S5 car is illegal, because you can't put an older engine in a newer car, and the S5 engine in an S4 car is legal, but needs to go to the bar.

since the T2's look so similar, and the big difference is the ECU/afm/bac/anything else with a part number, i'd just run the ecu/afm i'm supposed to and tell them i have the correct engine.

the cats are a grey area, if bought them now i think you need a carb number on them, but if you bought the cat between 1991 and 2008, then you don't.

any "mods" need the CARB sticker/reference, and they are all on the internet. if you are enterprising, HKS sold a CARB legal T4 kit and FMIC.... along with the intake.

GrossPolluter

iTrader: (1)

It's been so long, I think you are right on that one. I remember people with Hondas needing to register DOHC v-tec engines, but I think that was the civics then. I know they also had a way to distinguish between usa and jdm engines for the Honda engines. I think it was the last number on the blocks.

I remember intercooler mods were legal, but as far as going tmic to fmic, I don't remember. Cat back exhausts just need to pass sound regulations

DR_Knight

iTrader: (23)

Closure to this. I wanted to get the swap bar'd in case of a state ref but I procrastinated so ended up getting a ref ticket. Went to the ref and for the record fmic is legal on turbo car and intake piping and filter are legal on obd1.