Tuesday, January 16, 2007

ej25 swap into L SOHC version

Arg! I have done the swap. I have removed a 1.8l from my 95 OBDI L and installed a SOHC 2.5l from a 2001 (OBDII) car.

It depends... It will run perfectly fine off the 1.8 ECU, it will run rich though. if you want it act 100% like a 2.5 RS then change the harness and ECU Etc.

I did it cause my 1.8l had so many oil leaks i was sick of chasing down and wanted more power.

2.5 bolts right into the mounts and trans, i used a stock 2.5l flywheel clutch and pressure plate althoug the 1.8s will work.

Due to the idle air control setup and connections to the ECU, the 1.8 throttle body was retained. a blockoff plate was made to cover the idle air port on the newer 2.5 manifold.

the new style fuel injector connectors were spliced onto the 1.8 harness becuase i used the newer style injectors on the 01' 2.5.

crank and cam sensors, engne temp sensor, and oil press switch all plugged right in to the 1.8 wiring.

the temp gauge sensor was rewired, the older 1.8 had a small sensor with 1 wire whereas the newer 2,5 had a newer 3 wire sensor, i changed the connector to the newer sensor, blocked off two of the pins and ran the bottom wire to the temp guage.

I used the 1.8 coil pack and had plug wires made. if using a DOHC 2.5 stock 2.5 wires should work. I needed old style connectors on the coil end and newer style on the plug end. GOt them custom made and overnighted for 50 bucks from kingsborne wire werks.

EGR did not exist on the 2.5 so i hooked the harness to the solinoids which i retained and just plugged them off.

Knock sensor is not used

stock 1.8 intake and MAF sensor are used.

the only thing i can say to watch out for is the crank trigger on the timing sprocket that triggers the crank sensor.

the older cars it was all the same one, but for the newer (i think 2000 and up) there is a different ring on the manual trans cars. So if you want to use the 1.8 ECU you need to switch it over to the other timing spocket, or reuse the 1.8s

thats all i can think of.
Ive got over 7,000 miles on the 2.5 with the 1.8 ECU. I drive it hard too. it does run alittle too rich, occasionally when going WOT it bogs slightly cause when the ECU switches modes is over fuels, after a week i was used to this and learned to drive at 99% throttle and it does great, no problems. it will bog when really cold out for the same reason unless you let it warm up. if you start and drive it when cold it bogs if you get on it, if you let it warm up for a few min. it runs like normal.

Gas mileage on the 2.5 with the 1.8 ECU is around 26-28 MPG and i hit WOT at least 3 times every time i drive it.

Some vacuum lines will need to be rerouted, just sit down with a service manual and match them up. they will match up, just takes some time. My local dealer photocopied the pages i neededform the service manual for me. I am really happy with the results, it only cost me about 200 bucks because I already had the engine.

ej25dohc into ej18 car faq

okay. i have a 93 FWD L. 5 speed, ej18 car, i have a 98 DOHC RS motor (from an automatic RS) in my car now.
its a FWD with rear disc conversion +gastank.crossmember.sway blah, but this last conversion has driven me to nuts.

but - it runs, it pulls HARD, has no bogs and IT IDLES!!!!!!!!!!

its using
-1.8L engine wiring harness
-1.8L ecu and all wiring
-1.8L radiator / fans
-1.8L FWD tranny, flywheel, clutch (cable)
-1.8L crossmember
-1.8L throttle body with intergrated TPS and IAC
-1.8L MAF sensor, airbox, intake pipe
-1.8L ignitor
-1.8L charcol canister
-1.8L fuel pump
-1.8L fuel lines / filter
-1.8L brake booster line
-1.8L throttle body coolant line
-1.8L PCV setup

-2.5L DOHC motor
-2.5L intake manifold
-2.5L injectors
-2.5L sensors (all)
-2.5L coil packs
-2.5L plug wires

disabled (bc my car dosnt care anyway)
- no EGR - block off plate fab'd with alcoa 6061 t6 and dremmel tool
- blocked off IAC on manifold - use ej18 throttle body unit
- 1 million vacume lines blocked off - block off everything that u dont need for the bare essentials

--u can use from either ej18 or 98 DOHC ej25:
--throttle body gasket,
--exhaust manifold (they are the same dimensions - i measured them),
--catalytic convertor - EJ25 is bigger though + same for exhaust
--water pump - same part number
-- radiator cap - ditto although GDA is same also and supposedly 1.1 bar pressure (higher --> better)

**issues - ej18 powersteering lines are bent wrong for the ej25 motor, so it makes taking intake manifold off a hassle. also, u need to use the ej25 bracket to mount it on the engine with.

************************************************** **

it is a simple swap.
everything bolts in, mates up etc.

what i had problems with:

1. my ignitor was toast to begin with. i ran on front 2 cylinders for a while before i realized that #2 and #4 wernt getting spark. BTW your engine will run with the front 2 cylinders only, its slow but not that bad for 2 cylinders.
2. i had a million vacume leaks. use the charchol canister and its ej18 setup
3. ej25 powersteering pump has no plug on it. i have no idea what the ej18 plug on it does. so far, no issues
4. make sure your intake manifold gasket is good. mine was destroyed (by my stupidity and not recognized untill now). toast by #3, leads to intake manifold backfire in #3 and horrible loping idle.
5. dont mix up plug banks from coil. ie making #2,#4 fire at #1,#3 times. BAD.
6. i thought my headgasket was toast (it was the 3 layer). it probbly wasnt, but 13 hours yesterday made me have the new shiny metal 4 layer gasket . shiny. metal. 4 layer headgasket to take more boooooost...... its not that hard to swap. if u have some monkey knowedge, do it yourself. u need 2 friends to hold the cams in place for the left bank (#2/#4) they need to be centred @ lift and will spin out - scary noise if not attended to. note - GDA manual works perfectly - even the teeth #s are the same for spacing for the DOHC motor. same lifter setup etc for 87-98 dohc ej25. 96 is hydro lifter.
7. issues with bogging - not really. i dont have any bogs in my powerband. im guessing its not ideal - 1.8L map, but its not very far off.
8. redline issue = YES . it cuts at 6,000 rpm. im going to get it hacked to 7,000 by yoshio - hopefully with better power curves................

hmm anything else...... blah. i need to sleep right now. oh yeah, if u can rent / steal / buy an engine crane, id suggest u do so. we dropped the entire crossmember and jacked my car up a million inches to slide from underneath. its not bad, but the steering gear line up procedure SUCKS. (got it missmatched 4 times) blah.

any questions, hit me. pm me email me aim me, whatever. hawk296 is the bomb. hes saved my arse so many times on this swap........