Subaru Impreza GC8 & RS Forum & Community banner
1 - 20 of 42 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
What's the newest model year EJ25 ( EJ251 ?) that can be installed in a 2000 RS without rewiring or modification? Or do they all have to (ie, only a 2000-2001 will work)?

I tried searching but didn't come up with what I was looking for...

(Yes, swapping in a WRX or STI motor would be ideal but too costly and the wiring looks like a nightmare)

thanks!
 

·
Registered
99 Aspen White Coupe
Joined
·
443 Posts
I'm not sure, but most any will work, you just might have to reuse your old intake manifold. I think the current model is the EJ253, but I don't know how it's different than EJ251, or when the switch was (08?).
 

·
Registered
Joined
·
94 Posts
i bought a zero milage motor from Jasper engines and had it all installed for 5900. probably the best purchase ive ever made! i do agree a swap is more ideal, but this is just my daily and i dont need boost lol
 

·
Registered
Joined
·
2 Posts
Discussion Starter · #6 ·
"i'm not sure" either, which is why i asked :D I read on here that a 2005 EJ251 requires rewiring, but it's the problem on these boards (and I'm a guilty party as well), that lack of knowledge gets spread around as common knowledge...

I may be buying an RS shortly here with a blown engine and would like to know cost effective options to get it up and running. If low mileage newer motors will require ECU swaps, rewiring, or other hurdles, it won't be worth it, i'll just rebuild the engine
 

·
Registered
99 Aspen White Coupe
Joined
·
443 Posts
05 is "drive by wire" and should only require rewiring if you don't swap the intake manifold. So I'd just swap the intake manifold!

I'm also pretty sure that 98 and older engines won't fit, because phase 1 engines had a different bolt pattern when mating to the transmission. Might have been some other differences, so I'd just look at 99-05.

I bought a used engine less than a month ago for $500 with relatively high miles. Swapped it myself, so less than 600 total, and I don't burn any more oil! Not too hard, really good purchase.
 

·
Registered
00 2.5RS BRP
Joined
·
687 Posts
What's the newest model year EJ25 ( EJ251 ?) that can be installed in a 2000 RS without rewiring or modification? Or do they all have to (ie, only a 2000-2001 will work)?

I tried searching but didn't come up with what I was looking for...

(Yes, swapping in a WRX or STI motor would be ideal but too costly and the wiring looks like a nightmare)

thanks!
I think they have something like vvti in them now...forget what its called but if so then i doubt your computer will work with that


EDIT:^ just read that :D
 

·
Registered
1998 'Rally' Blue RS 2.5
Joined
·
61 Posts
98 has the DOHC whose heads have different port and bolt pattern for the intake...99 was the DOHC to SOHC transition year...Any SOHC (Phase II) 2.5 intake/engine combo will bolt together from 99/2000 thru at lease 05.

After 05, as some have mentioned, the variable timing thing was used so I am not sure about. (I think the intake would still bolt up but the vairable cam timing is something I have not looked into but am sure there would be ECU or other changes required to use in earlier cars)

Also as previously mentioned, 05 was the transition to DBW so the intake would not work without either an ECU and DBW specific wiring changes -OR- considerable machine work and spacer to convert it to a drive by cable friendly intake, however, same pattern so any 2000-2004 drive by cable intake manifold will fit.

How do I know??

I inadvertently bought a 2005 2.5 (wasn't aware it was DBW until it arrived...oops!) to replace my 98 DOHC with so I am learning as I go. I am currently using a 2000 intake manifold and am converting the 98 harness to fit the 2000 intake so it will plug n play into my 98 RS.

Hope that helps...
Les

 

·
Registered
2005 Baja Turbo
Joined
·
1,448 Posts
EJ253 is 06+ impreza 2.5i and has variable valve timing (165->175hp). EJ251 is 99-05 impreza 2.5rs.
That's not quite true. Not all 253's are DBW, 175 bhp engines. IIRC, the 253's do all run a 10:1 CR. My mum has a 253 in her 2003 Outback Wagon. The DBW is just a change to the throttle body, and the 175 bhp came from a combination of the intake manifold and exhaust manifolds being redesigned.

I had an EJ252 in my 2000 Legacy L Sedan, it was a combination of Ej253 block and Ej251 heads (or is that backwards?), though it ran a 9.7:1 CR. I believe the 1999-2000 RS had the EJ251, but I don't know for sure, since I've never owned a car with a 251. ;)
 

·
Premium Member
'17 Impreza Sport, '15 OB 3.6R
Joined
·
9,806 Posts
i bought a zero milage motor from Jasper engines and had it all installed for 5900. probably the best purchase ive ever made! i do agree a swap is more ideal, but this is just my daily and i dont need boost lol
A good point, but jeez at that price I'd have gone with an EJ205 install at Area1320 or ECS. That's what they charge, including the engine and all. Guess it seems steep for an EJ251, is all.

I'm sure most of us would be pretty happy with a fully reconditioned stock engine, regardless of what type of engine we have! So that's a good point.
 

·
Registered
1998 'Rally' Blue RS 2.5
Joined
·
61 Posts
Nope, all stock 98 RS (except for the wing, side graphics and lowering springs)...as far as I know.

And as far as the engine nomenclature EJ25?? I'm not up do date on any of that since doesn't really matter to me. 2.5 is 2.5. The early DOHC ver are plug and play exchanges with each other and the later phase II SOHC are plug n play exchanges for each other..up to the Variable timing versions and I haven't done any research on them. Y'all would know more about that aspect than I.

As far as the variances in factory HP ratings...those are not necessarily that reliable since they are SAE numbers (they gave up Net HP ratings system in 1971 or 1972, I think) and can vary from engine to engine by X percent so a difference of 10 rated HP here or there is basically moot, though the reasoning for the 10 or so HP variation are valid such as lighter internals, changes in cams, slight compression bumps, intake/exhaust changes, etc.

Those ratings can easily be made moot points or magnified slightly depending on what is or or is not done in synergism with the engine design..add too big an exhaust, too much cam or cam timing, over do this or under do that, etc can easily take an 175 HP engine and make it a loud 162 HP engine that "sounds good"


Les

 

·
Registered
01 RS, 02 RS
Joined
·
205 Posts
So has anyone figured out what you would have to do to put it into an earlier car, like 02 2.5rs, i found a low milage motor out of a 05 Outback for not a terrible price?
 

·
Registered
Joined
·
118 Posts
i bought a zero milage motor from Jasper engines and had it all installed for 5900. probably the best purchase ive ever made! i do agree a swap is more ideal, but this is just my daily and i dont need boost lol
sorry to get off topic, but holly shit dude.

you realise you coulda went STi swap with a front mount and a warranty for $1100 bucks less?

even my stealership quoted me $4500 bucks installed for a brand new 2005 2.5RS motor. no offence but you got way ripped off... i mean cool if your happy... but shit... shop around...
 

·
Registered
2006 2.5i San Remo Red SC
Joined
·
1,214 Posts
That's not quite true. Not all 253's are DBW, 175 bhp engines. IIRC, the 253's do all run a 10:1 CR. My mum has a 253 in her 2003 Outback Wagon. The DBW is just a change to the throttle body, and the 175 bhp came from a combination of the intake manifold and exhaust manifolds being redesigned.

I had an EJ252 in my 2000 Legacy L Sedan, it was a combination of Ej253 block and Ej251 heads (or is that backwards?), though it ran a 9.7:1 CR. I believe the 1999-2000 RS had the EJ251, but I don't know for sure, since I've never owned a car with a 251. ;)
actually your right and your wrong at the same time yes the intake manifold changed for a better one. One that most wrx's actually use or swap for. Second the throttle body is changed do to drive by wire set up which is relaiable but needs to be tuned for quicker response or reflash the ECU. Third the V-TEC VVT-i is AVLS or is that the 06+ wrx either way this set up is strickly manually. In other words there are extra lobes on the camshafts for this to work not like V-TEC which as extra cams..once speed builds they switch over to those lobes with the different duration.
For a brand new EJ253 4300 isn't bad at all its alot more relaible and with ECU and maybe harness its a steal of a deal. The only other way would be to look into a wrecked 2.5i yeah there out there but you never know if the engine was abused before hand and if you have the cash for say an engine which you'll have to break in then you can rest easier. Either way good choice if you want to stay N/A but I'm going swap.What I might do is either build up the EJ253 either CAMs or lower CR piston with x rods and boost the bad bwoy. Ohh and for you DOHC N/A guys our SOHC heads flow better tha nboth you and the wrx heads. Even better with boost wrx heads need the boost to flow better. So anyone out there looking to keep your heads keep them there more than able to get the job done. I need a :drunk:
 

·
Premium Member
95 L, 96 OUTBACK
Joined
·
2,918 Posts
Third the V-TEC VVT-i is AVLS or is that the 06+ wrx either way this set up is strickly manually. In other words there are extra lobes on the camshafts for this to work not like V-TEC which as extra cams..once speed builds they switch over to those lobes with the different duration.

They work the same. The new I-Vtec works just like the subaru system. Look it up.



Also bellhousing wise you can bolt 90-08 engines and tranys together. Newer (99+) have 8 bolts instead of 4. The starter is alittle differently bolted but workable. Along with other differences to make them work like linkage changes and halfshaft changes. If you have the right parts you can make use of them.
 
1 - 20 of 42 Posts
Top