TurboTim

iTrader: (11)

We have been looking for an FX35 to do a single turbo on. Actually our Single turbo system for the G35 should fit with very little mods.If you know anyone interested,tell them to contact us! We will do the first one at a substantical reduction in price for letting us use their vehicle!

jumbosrule

Best places to look for an FX for this type of project would be on one of these two FX sites. I know for sure there are some owners in the SanDiego area.

http://www.infinitiscene.com/

and

http://www.infinitifx.org/

jumbosrule

We have reached a temporary stopping point in the build, but have been totally successful so far. The parts I picked were all centered around the fact that the 5AT was the weak link. I knew I really couldn't build for more than 450whp, or else my tranny was a timebomb. Turns out we are running the GTR injectors at 85% duty cycle and that was at 105 degrees inside the shop. With cooler temperatures during the winter we'd be at risk of maxing out the injectors.

Also, turns out the OEM radiator can't keep up with higher boost. At 12psi = 400whp and temperatures are in check. At 15psi = 430whp, temperatures rise until coolant overflow. A lot of that has to do with having the intercooler, transmission cooler and oil cooler ALL in front of the OEM radiator.

So we turned the boost back to safe operating levels and I'm sitting at 400whp. This car is SO much fun to drive.

Engine bay:





Here's the shop dyno run video with printout at 430whp.

http://www.houston-nissans.com/index...sg8515#msg8515

Definitely close now, but still need to make a few part adjustments to get that balance I want.

thom000001

/\/\/\

Yea the stock cooling system is pretty much completely inadequate once you go FI. We found that on my setup too. Time for more volume so larger radiator.

Tom

djamps

iTrader: (1)

+1 for a cheap, easy and very effective mod. There are several drop in replacements at least for the G/Z, hopefully they fit in your FX without too much trouble. I went with PWR, not a 'perfect' fit but good enough. My temps stay within 5-8c in and out of boost at all times now.

jumbosrule

Thanks y'all - good to know. Also had the suggestion to switch to npg+ coolant. I was recently told that the 35R turbo is a little small for the engine and so IATs go up as boost approaches 20psi - the rad can't keep up.

Maybe time for water/meth... lol.

streetzlegend

iTrader: (2)

Awesome build man, love the FX.

I havent done hard research on npg+ but from the very little knowledge I have of it, it wont benefit you. Reason being is that, your problem is that you have poor flow going through the radiator, if you go with npg+, you still have poor flow, your temps will still go up, although you wont have increased pressure nor boiling of water/coolant, temp will still go up.

Also, I dont think the stock radiator is a problem either, its just the stuff you have infront of it like you said. With a built block, single turbo, 15-17psi, I have a stock radiator and temps are always in the low 190's, even at WOT temps stay pretty much the same as before I went WOT, sometimes it actually drops (this is also in Miami weather), oh and its a maxima. So yeah your radiator is not the issue. I have about 80% water, a bottle of Water Wetter , and the rest coolant. Meth/water will def help, I use it all the time, but with no meth, coolant temps are still the same.

str8dum1

iTrader: (11)

switching to Evans is not trivial either. You gotta completely flush the block of all water. They 2 cannot be mixed for it to work properly.


your situation sounds like headlift....

thom000001

Remember the heat isn't a function of boost pressure but a function of HP in general. The more power you make, the more heat you make (regardless of how you make it). And you need to dissipate it somehow.

The stock cooling system is VERY small. It is about as small as you can make it to keep weight down. When moving at highway speeds it isn't an issue (normally), but at low speeds or no speed (i.e. dyno) it becomes a huge issue. There just isn't enough volume of fluid in the stock radiator to really be adequate for these cars when FI. Most cars have same problem, especially when you hang a big IC out in front too (as you mentioned) to impede airflow. But once you go to a larger volume core, you eliminate the issue.

Tom

jumbosrule

Thanks for the inputs all. Definitely going with a Koyo R 36mm core on the shop's recommendation. Also a Nismo thermostat set 20 deg lower than stock.


Streetz - I can get coolant to spill out the overflow tank but temperatures never rise more than a couple needle ticks. It's not overheating, it just can't contain the coolant pressure. I do think a larger core is the answer. If I drive around for a while the coolant will recede from the overflow reservoir but if I stop the car it starts puking coolant out the reservoir vent. No bueno.
Ideally I'd set up both the tranny cooler and the oil cooler "remotely" so the fans would move air through them no matter where they are. But it's more trouble than it is worth when the new radiator will solve the coolant issue without moving the other cooler cores.

I took a few photos of the engine bay now that the parts have been ceramic coated. Also continued insulation - layer of dynamat and a hoodliner in the bay. I can't romp on the car yet but I definitely have fun.

streetzlegend

iTrader: (2)

Sounds good, I like the dynamat idea. For the coolant, I used to have similar issue with overfill tank getting filled to the max and eventually leaking out, first thing I changed was the radiator cap since it was old, put a 16psi one vs. 12psi stock I had. Problem continued, eventually turned out to be the headgasket(combustion pressure going into cooling passages), no other symptom, just tank getting overfilled with temp still normal. Just make sure the issue your having is not head gasket.

jumbosrule

Yes - great minds think alike! I actually asked the shop to sniff the coolant for that very reason. It's in the job jar.

They seem to have a lot of confidence in the fact that we are boiling the coolant at certain points and then flash heating under prolonged boost. Starting with the lower temperature setpoint of the Nismo thermostat should keep those boiling points in check along with the larger core radiator:

"the thermostat is definitely the lion's share of the problem, its keeping the temps hovering way high for a turbo VQ, the system is definitely getting boiling points with the temps being that high in stock fashion then flash heating under prolonged boost. Lowering the average temperature as a whole then increasing the efficiency of the radiator will bring the overall temps down and keep them in check. That will remove the flash boiling of the coolant as well which will keep the system from pressurizing to the point of overflow"

I'm ok with doing the radiator because my whole build philosophy has been a measure of overkill to ensure longevity. No reason to skimp on this particular system if this build can benefit. New radiator is coming with a higher pressure cap.

streetzlegend

iTrader: (2)

Good, also wanted to mention. I notice your using the HR head gasket, I am hoping that they did the small modification to the coolant passage to benefit from the HR gasket, right?

A cooler tstat will def help, sometimes it kind of annoys me though, since it takes longer for coolant to reach operating temp's, and piston slap dosnt go away till then, so I just sit there longer than I want to. But once your driving, them temps stay low, I have not had any issues with just HR coolant passage mod, water wetter, and thats basically it.

str8dum1

iTrader: (11)

huh? That makes no sense. Once the t-stat is open, its open. It's NOT keeping the temps hovering way high for a turbo VQ If your coolant is that hot, that has NOTHING to do with the T-stat. Thats a radiator problem.

If your tuner is telling you that, I'd find a new tuner.

jumbosrule

Think you might be interpreting what he said a little too harshly. What I got out of that was that the "hovering" was around the OEM thermostat setpoint. Since that's about 20 degrees higher than the Nismo, it takes less heat to reach boiling more quickly. It maintains constant temps there, leaving less room for heat spikes on hard pulls.

With a lower tstat, temp spikes can be absorbed more easily without boiling the coolant, and maintain the lower temp level with less risk.

My temperatures are not rising very much - I'm just puking coolant after hard pulls. It's either because we are boiling the coolant or because there is a headgasket issue. And to answer streetz, yes - the HR gasket was specifically machined for my DE application at the same shop that did the longblock package. Not sure if this matters, but I also included the pathfinder cooling mod in my build.

streetzlegend

iTrader: (2)

the gasket was modified?! your not supposed to modify it, your supposed to modify the actual block, look at this JimWolf pdf http://www.jimwolftechnology.com/wol...HEAD_BOLTS.pdf

Look at the bottom left of the first page, it shows what you are supposed to cut on the block, basically the entrance of the coolant passage into the block from the water pump. The HR gasket is different than the DE because not only the firering but also the openings are spread among all three cylinders (per head), so a more even flow and fluid enters into the side of the exhaust valves for better cooling. But in order to benefit from it more, you need to increase the flow into the block.

jumbosrule

Understand - thanks for the detailed info, seriously.

I'll have to do a little digging. The install shop farmed out the longblock package to a local machine shop they have a relationship with. I never visited the machine shop and the heads arrived assembled to the block with the gasket in place.

Back when all that was happening and I was getting email updates, I thought I remembered them saying they machined the actual gasket but if that sounds crazy then maybe I'm remembering incorrectly. It could have been they completed machining on the block to accept the HR gasket. I'll find out.

streetzlegend

iTrader: (2)

No problem, the HR gasket just drops in with no modifications at all. But the block machining is a must to improve flow. Hopefully thats what they did.

Jtran Studios

iTrader: (3)

in regards to the npg+. it works. it works great. we have ran it on one of our customer's cars and it dropped the temp down 15 degree's across the board. what we love about it is the fact that it nevers boils and basically builds zero pressure. with the npg+ you have to of course drain the block and run the prep fluid through before dumping in the npg+ to make sure the original coolant doesnt contaminate the npg+. if done correctly, it will drop your coolant temp across the board. if you run the npg+ remember you have to remove your thermostat and run rather a zero psi cap or 7 psi cap.

jumbosrule

Great info - thanks.

Interesting in that there's no need for a tstat - simplifies the overall system once you get everything prepped for the npg+. One less thing to break or replace. Pretty cool mod.

Any negatives to running this way? Any long term experience? Why don't more people run this stuff standard?