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Hey all,

What are your suggestions on using an RBE25det head on my current motor? To be able run higher boost? Is this a watse of money? RB25det Head cost around 700buks 2nd hand.

Regards Shorty =P

Edited by shorty_01
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my swap is finished now :). It take me from 15:00 Friday to 16:00 Sunday without a rest, just a few hours of sleep right in the garage :D.

rb25det neo inside.

Parts needed:

- rb25det neo with the same final ratio in the front diff as it is in the rear

- airbox for air filter from a turbo car (or you can use a pod filter)

- intercooler with pipng

- frontpipe from a turbo car (the rest of the exhaust system will work but it is wise to change it for turbo parts, i will do it in the nearist future)

- harness for boost solenoid and boost solenoid itself (enr33 has this harness in s1 versions, but there is no one in s2)

- adsorber canister from a turbo car (or a one-way valve in it`s pipng)

- a pipe for a vacuum brake booster (NEO has an outlet pipe on the manifold in the other direction) but u can modify the stock enr33 pipe, but remember that it has a one-way valve in it.

- ecr33 ecu suitable for your crankshaft position sensor (i have hitachi black sensor same as neo has on my rb25de). Note that afaik mitsubishi and hitachi sensors have different fittings, so they can be used only with the same camshafts.

i think this is all, may be i forgot smth.

what was done:

- right part of front suspension disassembled as i don`t know other way of taking out right driveshaft.

- gearbox removed -- maybe someone can take a 4wd engine out with it still in the car but we couldn`t.

- all auxiliary devices where transfered from the old engine.

- oil pressure sensor, O2 sensor, TPS (needs mechanical modifing because it interfere with the TCS housing on the NEO, but don`t use NEO TPS sensor as it has different resistance -- it cost me an hour of thinking what is wrong with the car :P), all other sensors are the same.

- there was harness work for vtc, aac, boost control solenoid and i think this is all. there is no need to connect "air regulator" used for cold start -- it is fully mechanical on the neo. the only thing that i miss is the FICD solenoid -- so i have a small drop in rpm when a/c engages.

i think this is all you need to know :D. this is not very hard -- the hardest part was to install the gearbox.

i`m in russia now -- never visited AU, but maybe some day i can do this :thumbsup:

idle is the same as it was on rb25de -- about 700 rpm when hot. it still reacts with higher rpm for power steering load, but there is a slight drop in rpm when a/c engages -- but just for a second -- after that aac increases rpm fo normal level.

neo engines have mechanical valve for adding rpm under ps load, but there is no place to fit this valve in r33. well, u can fit the power steering high pressure pipe with this valve into r33 and it will work. unfirtunately this pipe was damaged in the accident in the stagea i took engine from.

there was no time to make any pictures, sorry. there is a small video of the first start made by a cell phone, awfull quality.

Car runs better than before (i feel good torque from 2500 rpm) but sure it can do it better :(.

The nearist todo: to swap exhaust to a stock turbo version or some jdm cat back exhaust (i`m not sure my wife will like it :)) -- N/A exhaust is evil on a turbo car. After that i`m planing to do some dyno measurements.

Cheap mechanical boost gauge shows 0.25 kpa before 4500 rpm and 0.5 after boost solenoid engages, but i`m not sure it is accurate enough -- i`m looking where to purchase defi or apexi gauges.

Edited by Stronzo

oh, i forgot: the fuel evaporation system (black canister near to the air filter box) still isn`t functioning. It is ECU controlled in NEO -- so now control valve is closed all the time, but i`m sure i can make it work -- the problem is i don`t feel anything negative (gazoline smell in hot wheather) :( -- so there is no motivation to fix it :).

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