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ahh cheers dude. Yeah my kando lines are fine as far as i can tell. They also sent me the wrong size banjo fitting first time round haha.

I got my package last week from Kando, mofo sent me the wrong crush washers lol.. 2x too many medium ones and 2x short for the smaller ones...

Still waiting on my hypergear turbo... [haz a gate mounted on it] wooooo

  • 3 months later...

So no updates in a while. Good news is my compression test was all between 167-170.

Bad news is latest test shows 161,155,140,150,144,113. I am suspecting that the head is warped, don't think the headgasket could be that rooted all round could it? Warped head means throw away yeah or is it able to be machined true again and i will just run a slightly thicker headgasket to compensate? Either way bad news.

But the good news is that i have 2 RB30 bottom ends sitting in the shed waiting for me to pull the engine out :)

Should also say that i did do 4 track days with the NEO in and it was amazing to drive. It never missed a beat until i got to Winton for the matsuri this year and it did nothing but overheat. Flushed (forwards and backwards) the engine and radiator, took the thermostat out, front bar off, replaced radiator and nothing could keep it cool. Once it got over 100deg it would just keep going to 120+deg.

Cool down laps (fast and slow and varying RPM) spraying water over the intercooler and radiator, pouring water on the radiator. Nothing could bring the temp down except shutting it down and leaving it sit.

I pretty much decided i wasn't going to drive 20 hours to not drive so i thrashed it as hard as i could until it started to overheat (maybe 4-5 laps a session) so i can't say it didn't treat me well, i was giving it hell. Not showing any signs of a f**ked headgasket. No oil in water or bubbling radiator, just the low compression. It still idles fine and drives fine, obviously you can feel its substantially down on power but still gets up and goes when it comes onto boost.

Anyway, the general plan in RB25/30 NEO, 6BOOST high mount, 45mm Turbosmart gate, Hypergear SS2, Greddy FFP, Xspurt 1000cc, E85.

Yeah i know that that is what made me suspect head gasket in the first place, i just meant no other signs, usually you get the overheating, oil/water mix and bubbling in your cooling system.

Yeah me too for the same reason haha. I was going to do a leak down test but in the end i decided i will take the time to do everything properly and the way i wanted it. Before i wanted to keep it with standard plenum and manifolds with low mount internal gate. But i decided with the height the car sits at and being able to see the roll cage through the rear window, if i get pulled over i will be getting defected anyway, not much i can do to hide it.

May as well go and make it an all out track car now and drive it until rego expires or the boys in blue catch up with me haha. I was thinking about it today as well, when i replaced the manifold studs the second time i forgot to hook the wastegate actuator up and i took it for a drive. I was watching all my guages when i went WOT but i saw the boost spike to 2.4 BAR (35psi) and ever since then i have had the overheating issues. Is a single spike like that enough to lift the head? If so it explains a few different things.

I am really hoping that the head just got lifted and hasn't warped at all.

Yerp, I know that from personal experience... Stock VQ's don't like 50+ psi apparently. :P

A set of ARP or oversized bolts and a new MLS head gasket should have you up and running again, unless it leaned out severely...

My stock NEO is still holding up after countless days of abuse, just recently we decided to screw ARP head studs in one at a time so the engine stayed sealed, just for safety! Have had a boost spike similar when i blew the bottom gate line off and its still good :)

I have a spare Neo sitting in my shed, and 2 RB30 blocks. I'm going to put one Neo head on an unopened block and see how it goes. I'll also slowly rebuild the other 30 and just wait for the first one to go pop.

RB25/30 Neo, Hypergear SS2, External gate, 6Boost, Greddy FFP, X-Spurt 1000cc injectors, Adaptronic, E85.

That's the general plan :)

  • Like 1

Got the head skimmed in preparation for Cometic MLS head gasket, apparently the head was pretty much dead straight, good news! The machinist removed 4-5 thou so not enough to effect compression really. Will be running a standard size (1.3mm) head gasket.

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