so my friend just blew his GSR motor

Easy, the GSR was well beyond it's engines safe top speed at 70mph.

 

Why was the engine rebuilt 6 months ago? It could have been a shoddy rebuild, which I see more often than not these days.

 

Sorry Ryan, it was a sad attempt at humor. I meant that the car is not capable of 70mph even with a good motor.

Just like Korr said, bad rebuild at the dealer.

 

Don't need pressure, just an odd bit of engine...say a piston, but more likely a connecting rod...to come undone and hence try to free itself in whatever direction it was traveling at the time, barring other bits getting in its way. I've seen a rod break out a portion of the block on a Chevrolet 5.7l while the vehicle was idling.

 

not sure what a GSR engine is over there, if someone here told me their GSR engine was rebuilt by Honda then there might be reason for concern... GSR is a mitsubishi "performance" model badge.

anyhoo, now that we've established my circumstances have no relevance whatsoever... my GSR "let go" once, not as bad as this, and i had a lot less knowledge about what i was looking at back then, so it wasn't much more than a busted belt, siezed water pump, and possible valve/piston collision. this was just under light load at about 20mph in 2nd gear through a busy intersection.

 

holes in the block are usually caused by a rod letting go. Cause: bad bearings, over revving, etc. How much oil in the engine when it blew? Since it was rebuilt 6 months ago, I'd want to look at the main bearings, the piston pin areas. Are they blue? If so, lubrication failure, is the bearing surface scarred? could be the result of a bad fit. the motor needs to come apart.

Art

 

I suspect a conrod let go.

Properly built, those engines should be able to turn 9krpm+ for a short time and still be 'OK' (not that I'd do it willingly...) At 70mph, how fast is the GSR motor turning? Unless it's 12k+, I suspect a bad rebuild.

If the rebuilder didn't torque a rod cap properly, it can come off at any time, and put a hole right through the block, even at idle.

 

Just a guess, but I would say he was driving an Acura(Honda) Integra GSR. but you are in AU.

And it went right after a rebuild at a dealer? Extremely poor workmanship. Those are good motors and come in a variety of trim. Having a GSR motor blow should fall back on the dealer that did the work.

 

I agree. But, I've seen this too many times and it is always a driver error. The motor was rebuilt six months ago, and if your friend drives it spirited/aggressively at all, to the slightest degree, these symptoms would have come up a lot sooner than the not-so-sober night.

The story you are getting at 70mph is typical. Lets take that speed and add 20 to it for story-error. Now, going 90mph in 5th, dropping it down 3rd, accidentally hitting it into first - could not have been done without a blip. I doubt he did that. Now, trying for fourth and hitting second, that is all too typical. The motor didn't "just go". He mis shifted and is trying to cover his ass. But when misshifts happen, they will result in bent valves, and not a thrown rod. The head would be severely messed up, but this... I guess the only thing I can shed doubt into my own prognosis would be oil level. Lack of it = bam.