Blown Rb25Det 690Rwhp R33

[Jonahs33Liner]

I have an R33gtst with a complete rb25det series 1, a few weeks ago i was close to its top speed and all of a sudden heard a bang from the engine, lost all compression an had no response it just rolled to a stop, had a look and found a hole in left hand side of my block, its abit bigger than the size of a 52mm tacho face. It has had a good 30g spent on the engine including a fully forged bottom end, heaps of head work, bigger cams, bigger fuel system, greddy plenum, nearly everything was replaced with aftermarket gear, 4inch exhaust, t04Z ran 25psi low boost and 42 high making 690rwhp, uses a custom made switch wired to the microtech handcontroller to change from low to high whilst driving. It was only on low boost when the engine failed. The guy i bought it off and that built it has sadly passed away and he was the only one that knew the car inside out and who i spoke to if i ever needed anything. Ive pulled it apart and the only thing wrong with the head is one of the valve heads has snapped right at the start of the stem. Conrod & Bearings 2 & 3 have big chunks out of the left hand side where im guessing it hit the block. Is there anything else i should be checking or doing while i have the head off so when it goes back in there are no more dramas? I am not going to bother re-using any of the bottom end parts that are still okay and go for a completely new forged bottom end to ensure this doesnt happen again. Have been thinking about building a 30 block, fixing the broken valve and fitting the 25 head back on top because of the lag i used to get, or is a whole rb25 a must with the set up i have for this type of top end? Any advice would be muchly appreciated as i want to get the rebuild started asap and get it back on the road running even better than before cheers

Will post pics of the hole in block, head and bottom end internals in the next day or 2.

Edited May 17, 2012 by Jonahs33Liner

[Bsa]

Build the 30 and I suggest next time not saying you did it on the motorway

[NutR33]

if you have broken one valve, i personally would be replaceing all the valves or at a minuim removing and checking them.

It sounds like the motor was fairly serious, which means it prob has seen some big revs over its life, if one has valve has failed, whats to say that it wont happen again with the new bottom end.

Cheers

Luke

[Dobz]

RB25/30 is the go

Take pics of the damage and your setup.

Edited May 17, 2012 by Dobz

[GTScotT]

All new valves through the head and a general service. Put it back together with the new RB30 bottom end you suggested and have it retuned.

You dont need to have an RB25 for the setup you described. It will be a different outcome from 25 to 30 but I think the added torque will be a good thing in terms of lag. You should be happier than before.

Props, sounds like a nice car.

[Guilt-Toy]

id replace the ecu also.. imagine the timing drift on that! the timing is something you dont want to drift.. believe me.

[Rolls]

I dont understand why someone would run a $30k engine off a microtech.