How did I blow it up?
 

Hi All,

I have just bought a 96 type RA straight from Japan for use on track days but I have blown the big ends eating a porsche, first time out, lap 15 :)

A few queries:
1) Does the import need mapping just because of the fuel, I ran V Power?
2) What is the maximum safe boost for this engine? I have a blitz SBC which peaks around 1.1 bar.
3) What's the safe prolonged rev limit for this vehicle, me thinks I gave it too much too long :(

I have lots of queries but lets see what this returns, I think it's to do with ALL of the above.

Gary

Number one is your culprit i would say,the fuel over here isnt as good as over there in Japan, you may have had DET and knocked the big ends out,Getting it re-mapped might have been a good idea,you would also know the answers to number two and three.

Badluck.

Thanks, just means I have two hobbies now, track days and rebuilding engines :)

Or a failed oil pump due to its age - that's what happened to my 98 STi

I wouldn’t think that running v power would cause your problem even if the car was mapped for Jap fuel in fact it’s the best thing you can do in your circumstances short of running octane boosters, its possibly down to a number of reasons and those are not necessarily listed above

Your standard your standard boost is 13.64psi so just under a bar.

I'd whip the ecu out and have a look to see if there is some dodgy chip that's been fitted in Japan....they're often the cause of failures on "fresh imports".

But usualy this would be piston failure..

3 answers to this......

oil pump fail/sticking valve
low oil on the day
low oil in past which caused big end wear

Thanks, Interesting suggestion. Maybe time for a bit more info. The kid in Japan, I say kid as I imagine him to be 4'2", has done a lot to it. It's stripped out, roll caged, coil overs, bigger rad, induction, braced to death, you get the picture. He knew what he was doing and it's not the first time it's been driven in anger, so I'm thinking it might be something to do with coming to the UK or just me rattling 8000 revs down the straight in the hunt for Mr 911. One thing I thought was, if he's raised the boost he would have re mapped it. I'm wondering if he has swapped the ECU back when he let it go as its a standard ECU, I presume this is mot mappable?

I shall take it apart and have a look see. It's easy to get at, its ratchet strapped to the centre consul !!!

I'm having a standard WRX engine fitted, second hand, to get it back out on track, whilst have the original lump rebuilt just don't want to be swapping it every weekend and it's hard to know what went wrong. Will a good look at the crank help me?

I am thinking, get it rebuilt, mapped and not too many revs in future. Whats the safe limit for revs?

God I can go on eh.

You probably just overheated the cylinders, picked up a piston and knocked the ends, when you strip it if you have scoring on one or more pistons this is what happened, holding at high revs for too long is the cause, as std the car is speed limited and can never do that, so we delimit them and .... A blast thro the gears is great and not a problem, prolonged high revs in a high gear is baad. You are not the first and definately won't be the last. Mapping can help but is no guarentee.

cheers

bob

Also if you're running the OE TMIC they become ineffective very quickly with sustained periods of high boost

Is this true of all mapped Imprezas ? Will they all do this if friven flat out for a while (more so than other cars) ?

Whats's an OE TMIC
 

Sorry Guys, Scooby Newbie, whats an OE TMIC?

Original Equipment (i.e. Subaru) Top Mount Intercooler, as opposed to a FMIC (Front Mount Intercooler)

Took me a while to figure this out so don't worry

Dave

isnt 8000rpm a bit high for a RA?

yes sorry, as above. You mentioned the mods and you said a bigger rad, but I'm not sure whether that is relating to the intercooler or not. If you have the original intercooler for that year its mounted on top of the engine and is small and 'slanty' relative to the larger squarer later models.

But if this car is for trackwork a front mounted intercooler (FMIC) is the way to go :)

"8000 revs down the straight in the hunt for Mr 911"

Try changing up into fourth next time :-)

Ha, You assume I wasn't in fourth!!! That was my problem, every time I put it into 5th, it was no sooner time to change down, so I chose, wrongly, to hang on another couple of seconds into the braking area. Short shifting for me next time.

is the rev limit no 7500:wonder:

get yaself over to Welcome to Type-RA.co.uk - Home of the Subaru Impreza WRX Type RA, Impreza WRX STi Type RA, Impreza Type RA V Limited, Scooby V. Ltd :thumb: