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Alright... Diablo's heart has had it. It's a 2002 SP, running 5psi boost and is probably pushing 120kw at the wheels.

175,000kms old, it started making this really nasty noise after a recent run when I've over-reved it down while down-shifting just before a tight left turn. Engine oil was low as well. All 3 conditions together meant that the bearings might have been worned. Head cover was removed and the lifters were fine. The noise continued to occur even after a bit of cleaning. It happens when the car starts, sometimes when it's idling and sometimes when it's accelerating but doesn't appear when cruising at a constant speed.

So here are my 3 options (but please share if you have other options in mind):

A) I source another engine with lower kms and do a swap. Cheapest labour out of all 3 options;
B) I just work on the bottom end, replace the bearings and do all the seals and belts. Middle ground in terms of labour;
C) I take this opportunity and rebuild the entire engine. Upgrading selected internal parts to extend the life of my engine and to run a bit more boost.

Q1) What are people's thoughts on this?

For Option (C), I've read every single post I could find on the forum and they all say 'do what you need to do to get the results you want'. Sensible... if only I knew how each part of the engine would affect the end result. Which upgrade would safe guard what and what I can do without depending on what I want... they're all a mystery to me atm.

What I ultimately want is about 160kw at the wheels and I want it to last another good 200,000kms given regular servicing. Ideally running 2 or 3 boost settings so I can turn it on low boost in the rain, medium boost for normal city driving and high for spirited runs.

Q2) What should I upgrade and or get done if I choose Option (C) to achieve what I want above? (i.e. overbore?)

Q3) Is there anything else that I should do / upgrade at the same time? (regardless of which option I go)

As this is a rather expensive exercise, I'd like to get a second opinion as well.

Q4) Can people please recommend some referrals? (I live in Sydney and I'm willing to go anywhere in town)

*Thanks in advance.

Talked to an engine builder today, 200 extra to over bore to any standard size. His thought is why wouldn't you?

300 to balance and lighten. For na (what I was asking about) he says shooting yourself in the foot not ruling it.

Std rebuild, 2k including pistons and bearings. Not sure about rods.

I'd you want top make reliable power and run that for lots ok km, I would only do a full rebuild. I think you might be surprised how little you save just doing "rings and bearings"

Of course you can spend more, but I think that is outside the scope of where your aiming to get too.


Edit: re reading, I think I'm actually saying b.c. I think b should be spilt in to "simple reCo" or "built"

C implies head work, cams ect (too me) I'm not up on turbo stuff but sounds like this might be over kill for you r power target
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Also look at your oil pump depending on how much Rev you give it. the relief valve its the week, point they can be modded, our an external put in.

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Well.. if a full rebuild is only around $3k then that's somewhere I can bear with.

Unfortunately, I haven't found a source who would be anywhere near that price yet...

Don't think i'll need cams since i'm staying with turbo? (I could be very, very wrong though).

Thanks mate.

Buy supertechs and some ebay rods, do a rebuild yourself, or with a competant forum members help and then go run 20psi.

Dann

NitroDann wrote:Buy supertechs and some ebay rods, do a rebuild yourself, or with a competant forum members help and then go run 20psi.

Dann

Thanks Dann... but you and I both know my mechanical knowledge is only sufficient for GT5

That price was for me to get them the block and sump, they do the technical stuff, re assemble and give back to me. I would then need to put the head on and install into car.

Probably should have said that, my bad. :-$

Engine in/out isn't that hard, but would be a bit daunting for a first timmer. Pain in the ass with out the tools too.

Thinking about it more, I'm going to hazard a guess and say you've got no space and can't loose the car for a week or 2?

If you can live with out the car and have a friend / forum acquaintance that can help out then you could send it any where to get done.

By the reports the Ebay rods / pistons are ok for use.

Try pm img wozzah 1975 to get a non Sydney price.

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Question is how much you are prepared to spend to spend. I'd work backwards from there - that is, the "best" solution in my opinion is a rebuild, then working back to an engine swap as the last (and cheapest) option.

I don't have a budget in mind but anything over $5k would not sit too well.

The things I'm looking for are like what sailaholic said about 'balance and lighten' - you'll only ever do this when you have pulled the engine down to its pieces so it would be a good idea to do it at the same time.

Clutch is another possibility since minimal labour would be required if it's done at the same time.

$3000-$3500 for a full rebuild, where you drive up to the workshop and hand the keys to the mechanic, he does the lot, and pick it up and pay when done.

Start adding costs in there if you wanna put in fancy cams, forged pistons, balancing, lightening, polish/porting etc.

cams $400-$1000 grinds-new
pistons $400-$800
balance+lighten $500ish
full headwork $500ish

I disagree on some you're pricing.

balance and lightening QUOTED 300 by torque team in Brisbane yesterday.

I think your head work is a bit light. 1000 is what its costing me, for a port , shave, valve seats recut and valves cleaned up. New cams fitted and clearances checked.

New valves, lifters, spring a are extra to that if required.

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Im pretty sure wozzah1975 quoted around 1500 for a full rebuilt head WITH cams and porting.

Also pistons are NOT 800, and besides who would you put pistons in when they arent an issue till 350hp but rods dont cop 250hp?

Dann

NitroDann wrote:Im pretty sure wozzah1975 quoted around 1500 for a full rebuilt head WITH cams and porting.

Where was this done at...?

BadBong

Something to check is the keyway on the crankshaft?

NMX16 was experiencing some similar symptoms in his SP..

Brilliant write up with pics a few pages back in this thread..


t

Wozzah build race engines.

thats his job.

Dann