jumbomechanic

Hi guys,
The other day on the track my 1998 sti type r blew all its coolant out of the reservoir overflow and the engine went dead!
During my session the boost had been uncontrollable, sometimes close to 2 bar!
Since then, the engine will crank but wont go anywhere near starting!

So, today I removed the spark plugs to see if they were corroded, to confirm if the head gasket had blown....................

Instead, I found ALL 4 spark NGK plugs with the iridium tips missing!!! OMG!!!!

No wonder the car wont start!!

But now Im left wondering............

1. What would have caused that (would it be the overboosting)
2. What caused the coolant to overflow
3. What do I need to do to get the engine fixed and get back on the track?

Please help, as im fearing the worst and dreading taking it to my local subaru specialist....... £££££££££

merlin24

iTrader: (1)

Overboosting causing the head(s) to lift, combustion gases enter the cooling system and over pressure occurs dumping the coolant out, lack of cooling around the water jackets cause the combustion chamber temps rocket out of control /on set of det and melt the tips off the plugs and possible piston crown meltdown.

Do a compression test to see whats what internally on the engine, but the above scenario normally ends up with an engine being goosed.

Mick

RICHARD J

iTrader: (4)

Like Merlin says your engine is probably screwed & HG has certainly gone. I'd just remove it & strip it to see how bad it is, as a rebuild is certainly on the cards.

jumbomechanic

Thanks guys - pretty much what I was thinking..............

When you say screwed, are we talking new engine needed, or replace pistons, head gasket etc and thats usually enough?

Reason I ask is because I live in Dubai, but am back in the uk for xmas, so if I need to source a new engine whilst Im back, I need to get looking, or will I just be needing internal parts?

I know its impossible to say for sure until its stripped down, but any "usual" outcome advice is appreciated!

Thank you

Type_R_1984

Forge it if it's not been done already.

merlin24

iTrader: (1)

You will only know the extent of the damage once it is stripped and examined.
Crankcases can be bored provided it hasn't burst a liner, heads can be skimmed to correct distorsion and if the crank is shot - why not go for a 2.1 stroker seeing you have to replace the pistons and crank anyway.
You need to pinpoint the cause of the overboosting issue to safeguard your replacement engine (and wallet).

Mick

jumbomechanic

Oh, so it's some serious sh#t!

I have been looking at forged internals and stroker kits, but don't know which way to go? The car is imported from Japan and can not be used on the road here in Dubai, so is purely for track day fun! Trouble is, my budget is tight, as it's just a fun hobby!

So, I'm trying to end up with a strong engine, for as little money as possible, as spares and good labour are very hard to find out here!

I am back in uk for Xmas, so I'm wondering at what point does a newly rebuilt engine become a better option??

The Subaru specialist is so busy he doesn't think he can look at it before I return to uk, which really doesn't help, as I could do with a shopping list/idea of the damage before I come home??

Any ideas of spares/engines/kits etc would be greatly appreciated!

sonic93

iTrader: (16)

By the sounds of it you one and truly smashed it to pieces buy yourself a new age shortblock 800 quid fit that put your heads ancileres on. Buy your self a new oil pump if new engine don't have one

jumbomechanic

So a new STI short block? What exactly does short block mean, and what advantage is the new age one over a ej20 one?

I guess my heads will need re-working if theyve warped?

And then there all the internals to buy? Forged I guess? £££££££

sonic93

iTrader: (16)

The new age uk engines have forged internals as standard there good to a certain extent. There be good for 450bhp. So just a case of getting hold of Matty b (mb developments) he's a breaker get a short block /bottom end and get the heads skimmed and fit them.

AS Performance

iTrader: (4)

STi's only and no guarantee over 400 IMO.......plenty have gone pop just the same, main advantage is the better rods (pistons whilst uprated are not "forged" as an aftermarket Mahle, CP, etc. would be)

jumbomechanic

Thanks for the replies..............

Im sorry to sound stupid, but Im not very knowledgeable on these things.................

Am I understanding that an UK Sti 7 has a stronger bottom end than my current jdm V4 sti type R, but does NOT have forged internals? And it is good for approx 400 bhp?

Does the jdm sti v7 have an even stronger bottom end than the uk sti v7?

What exactly does a bottom end include, and apart from having my heads skimmed, what other parts will I need to replace?

Thanks again guys!

What a costly track day eh???!!!!

merlin24

iTrader: (1)

New age STi has a semi closed deck block ( open deck on V4 ), bolt type con rods (nut type on V4), rear thrust crank (center thrust on V4) and OEM HF Forged pistons (OEM HF forged on V4 STi and Type R).

Mick

jumbomechanic

Wow, thanks for that Mick - really appreciate it!

So using my car purely for track day fun, would you just put the bottom end in as standard with my original heads bolted to it, or would you change any "weaker" items (and what are they please)!!!?

Thanks again for people's help!

ditchmyster

iTrader: (7)

I'd buy my parts from these guys and have them shipped to dubai then you'll avoid UK taxes and duty.

http://realstreetperformance.com/sto...your-block-69/

merlin24

iTrader: (1)

If the budget allows, fit some steel rods and forged pistons for peace of mind because you just know that 400 brake will never be enough

If you are doing track days in Dubai, then good heat management of the coolant and oil systems should be a priority for the well being of the engine.

Mick

jumbomechanic

Thanks again Mick,

So in your opinion (you sound very knowledgeable in this subject), would using a standard v7 sti bottom end with my v4 heads be a reasonable engine?

I guess I would need ARP head bolts, uprated head gasket, oil coller and temp guage and better oil pump?

Do I ned bigger injectors and fuel pump and regulator etc with this set up, or can I use standard things?

I guess a new ecu and remap are needed??

Wow, does it ever end? :-(

Welloilbeefhooked

iTrader: (3)

I have heard before that the oe sti pistons were not forged in the sense that everyone thinks they are, so how are they uprated over standard wrx pistons?

merlin24

iTrader: (1)

If your ultimate aim is 400 with a similar torque figure, then a standard Newage Sti bottom end mated to your type R heads will do the job just fine.

But (and there is always a but) I would prefer to see a Safety margin built into the engine seeing as it is being tracked.
Using steel rods and forged pistons will give you the headroom for any future increase in power/torque plus they will be able to cope with the rigours of the track environment better than a standard bottom end would.

ARP head studs along with the other items you mentioned would be a very wise choice to build a strong engine. You should also consider at least fitting a baffle plate (RCM or Cosworth) to help reduce oil surge on the track.

Mick