I have a "spare" VQ35DE and plan to build it for FI, going after ca. 500-550WHP.

I already have ~50mm thick radiator and wonder what should I do next regarding engine cooling.

Found two possible options: use HR gaskets and mod the block -or- do "pathfinder" mod.

Any comments on that?

 

Just go waterless with evans cooling

http://www.evanscooling.com/

 

Way too radical for me. I prefer old school water-based coolant.

 

go with both...

 

The pathfinder mod is bolt on. No data I have seen to say which is more effective. I use pathfinder mod and evans coolant. If you are starting fresh, evans is worth it. It does cost more initially, but you will never have to replace it. I have never heard of a person running evans to experience headgasket failure, by the way. When my one of my fans failed, coolant temps skyrocketed but evans handled the spike no problem.

 

is it worth going from distilled water wetter to evans ?

As far as cooling ideas there is
54mm Aluminium radiator
2x 12" SPEL fans
Fan shroud
weather stripping foam in between rad and shroud, then rad and AC condenser
Path finder mod
Radiator cooling plate
Samco / Z1 hoses
Swirl pot
water wetter - engine ice - evans (not sure which is best)
Vented bonnet
and using E85
oh and Oil cooler

 

SPEL or SPAL? lol ... just giving you ****!

I run a single 16" on a custom bracket and it does just fine ...

IMO cooling fans dont do much over the speed of 30mph ... above 30mph its the passive air that cools your radiator -

 

I'll chime in and say if you do the pathfinder coolant modification you need to buy the OEM clamps. don't use worm clamps.

 

What's wrong with worm clamps?

 

HR head gaskets and block mod is 100% bullet proof as there is nothing to fail.

On the other hand I can use coolant crossover tube from JDM VQ30DET which has two thermostats in it (I believe 95 C+ 105C).

 

I already have ~50mm radiator, I use OEM fans and shroud, and my hood looks like that one:



Oil cooler is on my shopping list as well. Contemplating going cheap and dirty
and getting an ebay oil cooler + decent fittings/lines/etc.

I didn't consider using a swirl pot. Will check out.

 

During heat cycling over time, they can loosen. On my setup, there was evidence of small leaks everywhere there were worm clamps.

 

Nothing is bullet proof. I have heard of a couple of HR head gaskets failing (with HR TTY bolts). I have never heard of an HKS headgasket failing (with L19s).

That aside, if the question is which would cool better, there is no data to reach a conclusion.

One of the benefits of Evans is that coolant becomes less prone to leaks. The fluid is thick enough that even without a clamp at all (worm or otherwise), coolant leaks minimally. It also has a really nice smell. :-)

 

Eliminate the OEM oil cooler, run an aftermarket oil cooler with a sandwich plate between the filter and block. Helps a lot. My Mishi rad is at ambient temp at the bottom, even during summer. It's kind of freaky. All of this in addition to the HR gasket and pathfinder mod and you should be good. If you went waterless too... You'd be looking really good.

 

I'm in the process of doing a build on my car and I asked aroind about the hr gasket setup. It's been almost 6-8 yrs since I did research on the best headgaskets/stud combo, so I figured that in that time there might be something new/better. I got a pretty definitive that hks/L19 is the best.

As far as Evans? I can't speak on that as I have done very minimal research on that.

 

Thanks for the comments, I'm leaning towards HR-style HG. This way there is no extra thermostat to fail.

BTW how do I size oil cooler? The hottest days in summer here are like 30-32*C max.

 

This will sound harsh... Don't be so naive to think that a possible second thermostat failing is a bigger issue than having to do extra machining to fit a headgaskets and tty bolt combo that a good majority would advise is not the best on the market. You would be better off IMHO, not running the cooling mod and running the hks/l19 combo.

 

OP do both + evans

 

Both the pathfinder mod and HR gasket with the machined block are what I'm looking to do on mine. No one has mentioned doing them together, is it a problem ?

 

Not sure - I think it would work fine but not be helpful. The way I read the coolant diagrams (link here to JWT PDF) is that the pathfinder mod provides the most coolant flow across all configurations (when both thermostats are open).

I think the HR gasket and mod really only make sense from an OEM perspective because you do have better flow around the cylinder heads with the exhaust side being treated first and no additional expense of the pathfinder parts.

Assuming you are going to install the pathfinder parts, the heads and the block seem to get equal flow so the whole issue with heads getting better coolant circulation with the HR gasket seems to goes out the window (again based on how I read the coolant flow diagram side-by-side comparison provided by JWT).

In addition, if you choose Evans coolant, the whole problem with flash boiling at the heads goes out the window, so none of this really matters, including probably the pathfinder mod.