So I Dropped A Rod In Cylinder 6

[09ONE_32]

Hey guys,

I am in need of some advice.

It all started when I was making my way out to QR for a drift practice on Sunday 21st of November I think it was. Coming onto the Ipswich motorway I was in second and gave it a stab and a clutch kick, everything was going fine and dandy until I hit third and then BANG shake rattle rattle grrr (all kinds of nasty noises) I clutched in and the engine died instantly. I was rolling with the clutch in trying to re-start it, but it wouldn't even turn over

Got towed to my mechanics, and then he went to hospital for 2 weeks. So finally we have the engine apart, and the rod in cylinder 6 twisted and then snapped (will post pictures, I'm using it as a paper weight at work). Here is where my problem lies. The engine was a decent piece of gear (or so I thought) It was a stroked RB25DET with forged internals, big set of cams, HKS cast Manifold and an early HKS T04 kit.

To get me back on the road quickly I am thinking of putting an RB20DET back in (car is an R32) while I build up an RB30DET. What I want to know is what are your opinions on this? Another idea was to put a stock RB25 back in while I build the RB30. But RB25's are expensive and hard to source at the moment, and I am only going to be ripping it out in less than 6 months anyway. But how much am I going to have to change to put the RB20 back in? Will the exhaust manifold bolt back up to the RB20? Is the deck height that much difference that the cooler pipes will have to be modified? What about engine mounts and cross member?

In essence I would prefer to put a RB20 in, because they are cheap and they rev and I know I will thrash the living shit out of it and have a great time doing it not caring. If there is going to be way too much stuff to change I will fork out for an RB25 but then have to treat it with kid gloves so it is still in good condition so I can re-sell when the RB30 goes in.

Sorry for the long thread, and thanks for reading.

[predator]

rb20 will drop back in easy enough, but you'll have to stuff around with the wiring changing it back to rb20 which is the ass of the thing..

stock 25 or wait.

[dontfeelcold]

did little bits of metal work there way through the engine and cause any extra damage?

[Duncan]

and why did the rod break? how bad was it pinging? or did a bearing spin?

[Blitz]

Thats a bit of a concern for the rod to do that under those circumstances.

Before you do anything, diagnose exactly what happened.

My first guess is a bearing problem

[andylaurel]

get a 25DE and bolt your shit on

cruise around in it until your built 30DET is finished then start thrashing again.

25DE is around $700

[PHATR32]

25 de sounds good

[09ONE_32]

did little bits of metal work there way through the engine and cause any extra damage?

Yes, yes they did.

Also when the rod broke, the piston continued up into the head and took a chunk out of it (not too bad though). My rebuilt T04 <1500km now has some pretty nasty co-axial play in it. And some "glitter" in the exhaust housing

[09ONE_32]

and why did the rod break? how bad was it pinging? or did a bearing spin?

Thats a bit of a concern for the rod to do that under those circumstances.

Before you do anything, diagnose exactly what happened.

My first guess is a bearing problem

My guess as to why the rod broke is that who ever built it in Japan didn't want to fork out the extra dosh for forged rods and just got the stockos shot peened and treated. Also the rev limiter was set pretty f**king high for a stroked engine, (I just tried to stay away from it) and with a chipped ecu I could not change this as I was waiting for my PFC injectors and an EBC to all go in at once.

I was so hoping for a spun bearing rather than a dropped rod, but alas they look to be in good condition. Especially considering the state of the oil that was in the engine when the car came over from Japan. Oil changes every 500km or so over half a dozen times and the oil was still totally pitch black after 100km or so.

[09ONE_32]

get a 25DE and bolt your shit on

cruise around in it until your built 30DET is finished then start thrashing again.

25DE is around $700

This leads me to my next question.

What about wiring for the RB25DE? Can I use the existing wiring loom and ecu from my RB25DET? Can I swap the DET injectors over into the DE manifold? What compression ratio does the RB25DE run?

I know a few people have done RB25 conversions this way on the cheap, so what kind of power will the DE tolerate with a decent tune?

Finally, how hard is it to get hold of an RB25DE? Is my best bet to cruise the forums looking or just go straight to an importer?