An evil plan is afoot

[BaronVonChickenPants]

A few great scrounging scores lately have meant I now have a few engine options for my tourer.

Gearbox will be EJ 5spd AWD from an S1/2 EJ22 Liberty, I have the flywheel to match the gearbox.

The basis for my evil plan kinda revolves around a complete EJ18 with loom and ECU, loom needs some "minor" repairs but everything important is there, this cost me bugger all so I am prepared to ditch it for a better option, thinking of using this as a temporary engine while a build a better one.

I have:

• Jap spec EJ20 DOHC intake manifold
• EJ25 short block, can not legally be registered as engine number is written off
• EJ20 short block, needs rebuild, engine number is all good
• Box of assorted ancillaries-aircon compressor, ps pump, etc
• May be getting another EJ25 short block with a legit engine number

So here's my evil plan so far (mind you vague at best):
Rebuild EJ20 using EJ25 internals, possibly shave the block slightly, maybe rehone the bore for EJ25 pistons.

The ultimate goal is the biggest capacity and best NA performance from the EJ20 block now and in the future lightly supercharged, 6psi or there abouts, enough to give it some pep, and an RS WAIC.

So thinking maybe having the block O-ringed while I rebuild it.

At this point I'm completely open to suggestions, what would be the best compromise between performance gained VS money spent.

I figure I'll have to get a new loom and ECU as well, thinking EJ25.

Is there any significant advantage between DOHC and SOHC heads aside from ease of fitting (yes I know some people have fitted DOHC to MY's, don't want this to get into one of those conversations, I won't to know purely performance perspectives)

Ultimately the tourer will have the crossbred kit so stoppping won't be a problem.

Will also be fitting L series control arms and lower stiffer suspension to improve handling.

I'm not after a performance monster, just a nice ride that goes hard.

Jordan.

[discopotato03]

I would be researching the EJ25 engine casings as although I'm not sure I did hear that they are wider between the head faces than an EJ20/22 .
Another thing to research is which are the closed deck casings because these are preferable in a performance application . Basically the tops of the cylinders are better supported and don't tend to walk around (breaking head gasket sealing) under high loads .
I did read at USMB that some people feel that the EJ25 was never designed from the outset to be a turbo engine and may not be terribly reliable if given purple hearts with turbo heat/torque .
Heads . In earlier times the twin over head cam valve trains (preferably with direct cam lobe on inverted bucket) was the way to make a performance cylinder head . The four smallish valves gave lots of valve area in a compact pent roofed combustion chamber so they breathed well and could have efficient combustion characteristics . The valves are small and light meaning they don't need a lot of spring pressure to seat them or prevent valve bounce . Direct lobe on bucket actuation is a quite low friction system . Some of the later SOHC 4 valves per cylinder heads do it with less moving parts (1 cam plus low friction roller tip rockers) making the head cheaper to manufacture and service and they can have the good chamber design as well . You don't get the variable cam timing sophistication thats available to twin cam heads but you may not need/want that either . SOHC EJ heads are not as tall as the DOHC version because the cam sits lower in the head casting (between the two rows of valves not above them) and doesn't require the taller "cam chest" area of the DOHC head .

Probably the easiest move would be an EJ22 Turbo engine (SOHC) if such a version exists in an MY . Supercharging is not childs play when you consider the blower drives involved and also the belt driven half turbo style blowers dont make much boost down low . If you must have the DOHC engine use the twin scroll header and turbo bits to have broad ranging torque and response .

Best of luck cheers A .

[steptoe]

EJ25 engine written off ??


the number is still legible ? surely a block has the right to be reconditioned and registered in anything again.

number illegible ? go to RTA and get a police check done on it, ask to have it machined off and reissued with a new number - just as an engine without a car ?? i wonder ??

you just wanna hide 2500cc inside 2000 cc !!

[BaronVonChickenPants]

EJ25 engine written off ??


the number is still legible ? surely a block has the right to be reconditioned and registered in anything again.

number illegible ? go to RTA and get a police check done on it, ask to have it machined off and reissued with a new number - just as an engine without a car ?? i wonder ??

Apparently something to do with it being replaced under warranty, was supposed to be destroyed or something *shrugs*

you just wanna hide 2500cc inside 2000 cc !!

Hell yeah

Jordan.