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Sorry I miss read about the 25det crank.

Why the low rev limit. Mark 1 of my 25de revved to 8 and mark 2 revs to 7400 due to fuel supply.

With 320rwkw it was happy to bang limi all day it wasn't revs that killed it anyway.

And there is bugger all difference in the cams mainly the cam timing but that won't stop it revving

I think its the exhaust back pressure at high rpm, cam timing and cams...a little bit of everything. The RB20 actually makes more power as the new engine falls over after 6,500rpm

So will try new turbo with bigger housing, going for the 12cm2, cam gears, cams etc and I am pretty sure will find a bucket load of top end. Will throw the 20G back on to compare to see if the billet turbo is any better. I think the 20G could be a good thing if we can get it breathing up top and get it to hold onto power. A solid 4,000rpm range of 300 odd rwkws would be pretty solid result

The 12cm housing shall at least enable me to flow plenty and see what the compressors will flow

Yes, the character of the 2L is more fun. Will be interesting to see how is goes for traction at the track when driving in anger

Phillip Island in late April. Trying to get my new suspension and rear end in for it so that I can throw in my new gearbox. I have to put the rear end in with the gearbox otehrwise will need to do the tailshaft twice. Gearbox feels fine but concerned it will have trouble with the torque of bigger engine on E85 with more power and track work. it has done 210,000kms but at the end of the day not "not going to go" because of functioning RB20 gearbox may let go

If the RB20 didnt split that heater hose then i would never have put this engine in. This was the "too cheap to pass up in case I got EPA'd engine" that I hoped would never get used.

Anyway. So after a Saturday of wasting Racepaces dyno time with fiddling with the 20G and 12cm housing...we are pretty sure we have run out ofcompressor but simply couldnt get thet thing to hold boost.

So knowing the Hypergate only had a piss weak 11 psi spring I have grabbed 3 more springs and should be able to find a good combo to get the gate to hold about 19psi...and us bleed what we want from there.

So cam gears are in. Tomei 256/8.5mm cams are in. 12cm housing on. 19psi springs in the gate and she is rolling onto the dyno still with the 20G as we speak. Plan is to get a good baseline for the 20G to back to back with the T67 and 73HTA.

All this testing is a ball ache, but the engineer in me loves it :)

I must admist I was having long , close looks at your car. I really like how you have done htings.

I think there is a definite thinking to how to build a car when you are a frustrated engineer that wants to drive and build cars for a living :) Not always the easy way, or the quick way OR the the cheap way....but he cool way :thumbsup:

Engine is meant to have new GTR valve springs. No signs that there is anything wrong with the engine at the moment, Seems all setup related. Not really a problem...just a combo not really working well together....which is to be expected when you throw 500cc at a 2L setup.

request thread title change to "A boy and his hatred for 350+ rwkw RB25de+t because broken in the head"

I am with you...the only thing that helps with the disdain I have for this motor is that its cheap and looks like an RB20, so is 2/3 the recipe of an RB20 :)

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