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Who knows mate, I wasn't at much more power than that myself remember. If you notice any loss of water or overfull overflow bottle it will have lifted... Mine has been doing it for ages it just failed completely the other day on the dyno.

The stock head studs are crap, designed to be the weak link so as not to damage the bottom end. If you are worried, get a set of ARP studs fitted, or VQ37 bolts are pretty good apparently. The heads shouldn't even have to come off...

Who knows mate, I wasn't at much more power than that myself remember. If you notice any loss of water or overfull overflow bottle it will have lifted... Mine has been doing it for ages it just failed completely the other day on the dyno.

The stock head studs are crap, designed to be the weak link so as not to damage the bottom end. If you are worried, get a set of ARP studs fitted, or VQ37 bolts are pretty good apparently. The heads shouldn't even have to come off...

Hmm ok that's kinda worrying...remember 6 months ago when I came over and you fixed the dodgy ECU connector and my overflow bottle was almost empty???

Edited by ironpaw

Are the head gaskets for the VQ35 the same as those for the VQ25? I see Nismo do VQ35 gaskets...

Nope, its a larger bore on the VQ35de and the water jackets don't line up either. Other than that the blocks seem to be identical.

Apparently the head gasket is the same for any VQ25 so there may be some aftermarket options in the US but I couldn't find anything in Japan when I searched. Unfortunately they wont be performance gaskets.

Either we leave these engines near stock or pay big bucks for custom parts, at least the 3.5de L19 studs fitted fine, perhaps with the main bolts replaced also we can push for much more? My pistons showed no signs of damage...

Finally got the engine back together, I also designed the block coolant mod today. It was too close to the rear coolant pipe to connect it there so I fed it up to the rear bleed point, all uphill so the air has a chance to make its way up quickly. It just needs a ball valve on top for bleeding and to fit the last 90 degree -10 fitting. I should have the car back on the road by next weekend. :cheers:

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  • 3 weeks later...

Well, few problems today.

It ran up fine, he did a fair bit of low end tuning first with no issue. Water level didn't drop, temps were under control and dropped back as soon as he backed off. All looked sweet until this weird missfire developed. Lucky there was a donor VQ25dd at the shop, I swapped some coilpacks around and found it wouldn't fix the issue so next I checked and gapped the new plugs. Again no issue with them. We decided to check the fuel side and found one of my Walbro's wasn't pumping properly causing it and after topping up the tank all was fixed. Looks like I am upgrading the pumps again...

The tuning continued, we decided on a safe 26psi tune which in AWD and with extra correction produced 310kw. I may drop the shaft and push for a good number some time later, once I am sure the engine is fine, but for now the car feels very strong and great to drive on the road. Definitely faster than before.

I have ordered a new set of 4000 DBA disks with A1RM pads for the Brembo's, that should sort out the brakes, then its ready for Phillip Island when I can get there. :)

Good to hear your hard work with gaskets & studs has paid off; I'm assuming you had an opportunity to fit the shorter geared front diff at the same time. :thumbsup:

310kw's at all 4 is a great result; you must be stoked!

The larger blades on the 76mm comp should help a lot compared to the smaller 71mm particularly midrange.

A little too much midrange, its making some funny surge noises at small throttle openings while coming on to boost. Glad its got the surge slots.

I still have my old GT3040 and it has a non-port shrouded comp cover. It didn't surge but it can depend on tuning if they are close to the edge. The compressor flow of a GTX 76mm comp is pretty similar on paper.

I wish you could back to back test this GT3040 against the GTX3076 I would love to see if there have been any real world gains with a billet wheel.

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