phunk2

Just as an interesting note... the oil/water exchanger made a comeback in the middle of 370z production. Perhaps 2011 or 2012. A half-*** band-aid by Nissan in attempt to get the ridiculous VHR oil temps under some control. You wouldnt believe how fast the VHR oil temps start to climb until you witness it.

But I couldnt agree more about ditching it. Its needless mess and complication for a car that is going to have a real oil cooler anyway. Its only remaining perk is faster oil warm-up which is a little bit of a concern with the front mount oil cooler. I would recommend letting the car warm up sitting still with no airflow for a minute or two just to let it get a little heat in the oil before putting all that airflow across the core. Even with the thermostatic sandwich, warmup takes much longer since the sandwich does not have 100% bypass.

phunk2

In the picture I posted, notice you can barely see in the corner of the picture that the oil cooler water line on the thermostat housing was plugged. You can pull the hose barb out because its just pressed in. Once out, I just tapped it for a NPT plug to seal it up. The 370z thermostat doesnt even have a hose barb there and might be a direct bolt up. It looks the same at a glance at least.

Unfortunately the big steel water pipe has to be welded on that end. While you are at it, you can do the throttle coolant line the same way. On the back water pipe you can just pull the barb out and tap it and plug, but you have to weld it up on the driver side steel pipe.

Another step is to ditch the radiator bypass hose... the big one hanging across the front of the engine. In theory this isnt the greatest idea but in practice it hasnt seemed to have a negative effect on my built DE for about 10 years now.

Escobar

iTrader: (27)

So you can pretty much delete all those small hoses then? Crazy. All you need is the lines going to the radiator on the top and bottom and the 2 that go through the firewall?

phunk2

ya I get rid of all that stuff. We also run the big pipe thats on the passenger side through the V of the block and through the center of the timing cover

bealljk

iTrader: (13)

It's up for argument/debate but it my opinion that the coolant bypass is in place to circulate coolant while the thermostat is closed. With that being said, I removed mine and put a small (3/8") hole in my thermostat plate to provide this circulation. My oil cooler and my heater core lines were also deleted and plugged.

taywan

iTrader: (53)

Str8dum- why can't you run a boost controller on a stock block? Or do you mean it isnt wise to?

Nobody would go uprev w a built block, why not?

And the cooler/warmer, could you not just delete the plate and connect the hoses and let the fluid flow?

Escobar

iTrader: (27)

good idea, that would be a hell of alot easier then having that stuff welded.

phunk2

You would not do that in theory because you have created a significant internal leak in the cooling circuit. The water has an easy route around the radiator regardless of thermostat position. I would expect this to significantly reduce the efficiency of the cooling system since a large percentage of flow will recycle without first seeing the radiator.

But the other side of that argument is that the stock oil/water exchanger isnt very restrictive to begin with, therefore this was happening all along. The counter argument would then be that eliminating this passage all-together should increase cooling system efficiency quite a bit by enforcing that all water is cooled by the radiator before recycling.

taywan

iTrader: (53)

So what about capping both lines ?

phunk2

Nothing wrong with the idea of it. I havent personally found a cap that I trusted the quality of for that purpose. Vacuum caps are always made of the worst quality rubber that I wouldnt trust not to break-down quickly.

But if you find some sort of cap that seems high quality enough and you are positive it will not blast-off from the water pressure, than this would produce the same results as plugging or welding just not as "clean" but obviously more reversible if that matters to you.

Escobar

iTrader: (27)

yea I think the best scenario is just to remove and weld it. Thats great it will help with cooling. Good info guys.

Escobar

iTrader: (27)

My other concern is my kit did not come with the " power steering pump fitting" # 45 on the parts list. Is this something thats required or can you work around it by bending the lines? Also, if im missing a stud or 2 from the kit, can I use the oem studs for the manifolds or they too long? thanks guys

phunk2

I am pretty sure you need it. I had a problem with my original Greddy one and I just took the stock one and cut it and welded it in the proper direction. That was a long time ago because when I moved my PS to the driver side of the motor I had to do it all different anyway.

I do not use any of the Greddy studs. I use all factory studs and I shorten a couple of them where they need to be short. I also dont use the provided Greddy nuts and lockwashers, I lathe the stock ones to a smaller flange diameter and tap through the locking part on the end so they thread nicer. I use them without any washer like stock. I also machine the Greddy manifold flanges flat where the nuts seat on them. The first couple times I discovered that the combo of SS studs and nuts seizes up and becomes extremely difficult to ever remove later, thats why I dont use the Greddy hardware. Plus I dont like how minimal their thread engagement into the cylinder head is. Their cast flanges are not flat, which is why I machine them. Tightening an uneven surface does a good job of seizing up the hardware too. The Greddy manifold hardware is very nice but it doesnt work out well for the exhaust manifolds. The lock washers end up bending open and smushing into the oversized flange holes, etc. Its a big mess. Much nicer the way I have been doing although I understand that way wouldnt be so simple for those without a full shop.

bealljk

iTrader: (13)

I bent mine but I messed it up in the process - it didnt seal up properly I bent it back and RTV'd it and it seems to hold.

I would cut and weld as phunk did as it's pretty important to free up as much space as you can.

I used OEM hardware on the flanges...I didnt machine-down the flanges but in hind-sight I should have - pretty good idea

Escobar

iTrader: (27)

ok, so since im having the coolant pipes welded I'll just have the power steering line welded up as well after I cut it. No big deal. So when you say you use the stock studs, do you leave all of them installed and just cut the ones that are too long? I found it very strange that greddy wants you to remove some and leave them out??? why would you want less studs for support and less area to make a good seal? makes no sense to me.

Escobar

iTrader: (27)

so I got my hr oil filter stud today and its un equal lengths as you can see in the pic. The other pics I saw in the thread it looked the same on both sides? It threads in all the way but just seemed odd? Im assuming the long threaded side goes into the engine and the short part sticks out for the filter.

phunk2

ive never played with that so I wouldnt know which way it is intended to go. If you try it both ways with the sandwich plate it might just end up only working one way. Just make sure everything gets adequate thread engagement and that the long end doesnt cover up anything that it shouldnt when threaded in.

phunk2

As for the studs, I dont remember which locations I ended up using, but it doesnt matter so long as you have 2 studs per exhaust port, across from one another, and that you can actually get a nut on them. There might be a spot or two that you can only get a nut on as you slide the manifold down the studs.

Escobar

iTrader: (27)

got ya. Thanks Charles!

Escobar

iTrader: (27)

its out! wasnt bad really. gonna get it on the stand and start bolting up turbos!