Leakdown And Compression Test Results

[Nate79]

I thought I'd get an idea of the engines health before spending big on a turbo upgrade. It was done at Allstar tuning in Brisbane and they seemed pretty happy with the results.

Compression

1-170

2-155

3-165

4-160

5-160

6-165

Leakdown

1-10%

2-20%

3-12%

4-16%

5-17%

6-10%

After a turbo upgrade my target is 260rwkw. Will the engine be able to handle it and should I be worried about cylinder 2?

Thanks in advance.

[sinistaGTR]

just give it a bash and if it blows up then rebuild it with forged pistons lol

[andylaurel]

thats pretty woeful

they should all be within 3-5 psi of each other

[MerlinTheHapyPig]

from memory.... spec for turbo rb's should be

all above 128psi

no more than 17psi variance

so your motor is within spec.. barely!

it sounds like it's getting to the stage where i would do a 'simple' rebuild, but if you can't do it yourself and have to pay someone to do it, wait until it get's really bad and do a full rebuild.

if it were me and i were running that much power i'd consider taking it apart, inspecting the pistons and bores (especially number 2) and bearings, give it a quick hone and some new rings and head gasket - (ie stuff you can do with engine in the car). If you need to pay someone to do that, may as well do everything while you're there though.

[Cubes]

Bah.. get some life out of it..

Wait until you start smelling it when you drive. lmao.

[Nate79]

Damn, that doesnt sound good at all . Looks like I'll have to put off the turbo and suspension upgrade and spend the dosh on a rebuild. I might aswell get some forged parts and go for a higher power figure later on. Its driven daily but I wanted to build it for track days and hillclimbs. Off to do some research, might have to PM SK and see what he thinks.

Thanks guys.

[Rolls]

Its not too bad, just drive it until it gets to the stage where its really down on power or its using alot of oil.

[GreddyGo]

It isnt really that bad,

How many km's has your engine done?

[Nate79]

Its got 92000 on the clock, but who knows with imports.

[The Mafia]

after 100,000 and a GT30 on the side of mine, and all of my own tuning

all about 160psi

Biggest variance was 4 psi

leakdown was 3% across all 6 cylinders.

Man, 20% leakdown means its f**ked. Rebuild it now before you damage it worse but blowing a piston in half.

[GreddyGo]

^^ True,

But if it's correct it has taken 92000 km's for the engine to wear to your results, do the math and you will still get a fair bit of milage before it goes! Keeping in mind the extra kw also.

Cheers

Josh

[Cubes]

Yep spend all your $$ now on support mods and bolt ons... Then when the motor gets noticably tired you have an excuse (for the missus) to get it rebuilt. Rebuild it now and then try to justify support mods after.. Doesn't always go down too well.

[Sydneykid]

Do they only do a "dry" leak down test?

You haven't put up "wet" leak down results, so I assume not.

Take it back and get them to do a "wet leak down test".

That will tell you if it's a valve seal problem or a ring seal problem.

If it's a valve seal problem then a simple (relatively) head service will fix it.

Post up the results "wet" leak down test and we will go from there.

cheers

[kjb_r33]

to me it looks ok, compression test should be within 10% of each other, cylinder leakage should be no more than 20% (one is borderline). You have to keep in mind that with the cylinder leakage, most of the pressure goes through the ring gaps. As sydneykid said, it should be done wet as well, even a wet compression test will tell you if its rings or a valve sealing problem.