I'm wondering the direction the coolant flows. I am going to run with no heater core so i'm trying to figure out if i can remove the coolant lines at the front of the engine on top the manifold. I think the coolant flows from the water pump thru the heads to the passenger side but then i'm lost. Does some of the coolant flow to the heater core,radiator, and the front coolant line. Anyone know?

 

 

Thanks jime. Thats the way i thought it went. So there shouldn't be any problem removing them.

 

Well just an update with this. There is a problem removing those coolant lines. My car would over heat due to the thermostat not opening. I tried 2 diffrent brand new thermostats so they were good. I have ended up running no thermostat and have no problems.I'm not exactly sure why the thermostat would not open but i beleive it to be that there is no coolant flow to the back of the thermostat coming from the top metal coolant line.

 

Holy ****. That is awesome. I mean its bad that your car was overheating but I was having the same problem. I crimped and welded shut my heater core lines because I don't have a heater in my 240 now. So it was overheating. So you just pulled out the T-stat? How is it not running too cool? I'm going to try that tomorrow.

 

I just pulled the thermostat It does run alot cooler. I'm not sure how cool though.I'm going to try to either hook the the top coolant line back up so the thermostat opens or try and run with no fans to get the temp up a little.

 

I just pulled the T-stat housing off and was very suprised. I've never pulled the T-stat off the VQ yet so I was suprised to find that its attached to the housing. How did you get your off? Did you just cut the little support legs and it came out or what?

 

Mine i think was oem had 2 screws securing the legs on.I just removed the screws and it came out. The aftermarket ones i bought the legs i could push together and turn the actuall thermostat and it would come out.A new thermostat with housing is only $15 so if you break it it's no big deal.

 

if you guys find its to cool like that you can make a little metal plate to bolt in there and you can exsperiment with diff size holes in a metal plate.
the plate can be bolted down like the thermostat is inside using the same bolt holes

 

That sounds like a great idea. Are you still runing a heater core?If not is this what you have done? Anyone know what the optimal temp is? I though it was like 165 but i could be wrong.

 

i still have my heater core and the stock is 183F. I would bet that your engine is running to cold which could be bad . If your engine is to cold could hurt HP to .

I run a 350z thermostat which is 169F stock which is perfect for what i have ,when i get the cash i will get a griffin to make sure it stays around that mark.

As for the plate idea i think you should atleast keep your temps in the 160's with a obd 2 tool you could see the exact temp your running

 

My t-stat has tamper proof flathead screws on it. The kind that are in bathrooms and ****. You can only tighten it because the loosening side is all bevelled(Sp?). WTF? Dumb move on Nissans part.

The stock t-stat is a 180 degree. My car always ran between 180 and 185 at speed. Occaisionally it would creep to 200 in traffic. Running cool is not bad for HP but could be bad for the motor because the oil doesn't get warm enough to be fully viscous. Ideally you want the motor to be at ambient temp and the oil to be in the low 200's. The cooler the motor the cooler the intake charge stays and therefore the more advance you can run. I'm going to pull mine out and I'll be able to tell what its running at because I have guages. If its real low I'll definitely give ya a heads up.

It doesn't seem to make sense that the 350 T-stat would help in this situation as the stocker is already open. T-stats are either open or closed. So when the stocker is open it is still posing a restriction because of the actual shape of the unit. Running no T-stat removes that restriction and allows the rad to do its job full time. This is certainly not a good final solution but it should work for a while. Maybe adapting a T-stat from a domestic V8 would work because those have much larger units than ours. I don't know. Just thinking out loud.

 

they all have the tamper proof bolts i replace them with tiny allen bolts .
i use a dremil to carefully cut a flat head slot for a screwdriver to take them out

 

Mine were phillips screws.

 

good call Kris. I'll do that.

 

Well I pulled it out using Kris's method and its now running way too cold at speed. On the highway I never see above 130. Crusing around town its up between 140 and 170. When its sitting for a long time it will climb indefinitely without the fans on. But once I flip the fan switch it will drop like a rock. At idle I can get it to drop down to like 140. I need another solution... The restriction seemd like a possibility but I don't want to do something ghetto like that.

 

what temp are you looking for?

 

I did a writeup a long time ago about changing the thermostat opening temp. It will work for both the 4th and 5th Gen thermostats. Just finished doing a 170 deg one for the 3.5 swap. Very simple and very effective.

You should also change the fan temp settings as well so the fan comes on at the lower temp as well, that can be done with a simple resistor in the temp sensor wire to the ecu.

 

I was hoping for a fairly consistant 170-190. I can't get near that on the highway.

Jime, you got a link to that writeup please. Thanks.

 

http://forums.maxima.org/showthread....ght=thermostat

I now put the spacer in the other end, pull out the shaft and drop the spacer in and replace the shaft, its much easier.

 

Thanks man. I'll check that out when i have time.