Blocking water ports l20b

[d510addict]

I have an L20b with w53 closed chambered head and l16 intake/exhaust. My head does not have the water ports for the intake mani and I was wondering if I could/would it be benificial to plug the lines from the lower rad area to the intake mani and  from the thermo housing to that line that goes from the lower rad to intake? The main reason why i ask this is my motor has been running quite warm (much warmer than with the other head I had on) I know it has warmed up quite a bit in the last few days but the running temp difference is quite high between the two heads and I really do not know of anything else that has changed other that those intake water ports and the outside temps.

[banzai510(hainz)]

try a cooler stat 54 mm 160?????

 

try drilling a 1/8 drill on the stat first to get rid of air bubbles

[Stoffregen Motorsports]

Did you check the head gasket before you installed the new head? Some gaskets may have different coolant passage holes in them. Rare, but I've seen it.

[datzenmike]

The ideal thing to do is drill the head so that there IS coolant flow through the intake. It warms up the air when motor is cold, helping the gas vaporize on col mornings, and cools the intake when it's hot out. By cooling the intake I mean it prevents radiant heat from the exhaust from baking the underside on the intake. Cooler air makes more power than hot. No sense in running over heated air into the motor... it promotes pre ignition, vapor lock, gas boiling in the carb and hard restarts. This will allow the motor to run an a narrower range of temperatures and this will make tuning it easier.

 

The line from the thermostat housing should be kept as it does a better job than drilling a hole in your thermostat.

 

You should be able to run a 180 thermostat with no problems. The easy way out is to run a colder thermostat, but when it gets cold out your motor won't make enough heat and will run like it's warming up all the time. Shitty performance and mileage. Motors are designed to run near 200F. If running too hot....

 

Are you running an L20B but with an L16/18 rad?????

Are the fins bent over or blocked with bugs, dirt, leaves?

Is there a fan shroud in place? This will increase the fan's efficiency.

Are you running proper anti freeze/coolant mix?

Is your timing retarded too much?

Are your exhaust valves too tight a clearance?

Is it possible you have a blown head gasket? Does it burp water from the rad overflow or use water?

[Will]

Are you running an L20B but with an L16/18 rad?????

 

Ah, so perhaps this is why my car has been running a bit hot since I swapped in the L20B !

[datzenmike]

I just checked my L18 and L220B 710s. Can't see any difference. Both are two core but looks like room for a front row. The L20B also has air. L16s may be way smaller on the 510s?

[d510addict]

The ideal thing to do is drill the head so that there IS coolant flow through the intake. It warms up the air when motor is cold, helping the gas vaporize on col mornings, and cools the intake when it's hot out. By cooling the intake I mean it prevents radiant heat from the exhaust from baking the underside on the intake. Cooler air makes more power than hot. No sense in running over heated air into the motor... it promotes pre ignition, vapor lock, gas boiling in the carb and hard restarts. This will allow the motor to run an a narrower range of temperatures and this will make tuning it easier.

 

The line from the thermostat housing should be kept as it does a better job than drilling a hole in your thermostat.

 

You should be able to run a 180 thermostat with no problems. The easy way out is to run a colder thermostat, but when it gets cold out your motor won't make enough heat and will run like it's warming up all the time. Shitty performance and mileage. Motors are designed to run near 200F. If running too hot....

 

Are you running an L20B but with an L16/18 rad?????

Are the fins bent over or blocked with bugs, dirt, leaves?

Is there a fan shroud in place? This will increase the fan's efficiency.

Are you running proper anti freeze/coolant mix?

Is your timing retarded too much?

Are your exhaust valves too tight a clearance?

Is it possible you have a blown head gasket? Does it burp water from the rad overflow or use water?

I have no clue what the rad is out of, its not a stock 521 rad and was there when i purchased the truck, which leads to a problem, I have no shroud for it and the stock 521 shroud wont fit. I am running 50/50 anti freeze/water, 6 deg btdc on my timing and 8 and 10 thousandths (intake/exhaust) cold settings though they are loose setting so probably closer to 9 and 11. I just finished swapping this head so it is a brand new gasket (well I had to start over when I had a shitty seal with the felpro) Now I am using the headgasket reccomended by Nissan (they were NLA through Nissan but I found some on ebay) so I do not beleive it is a blown head gasket. Now with that said, I am having some slight overflow problems with my coolant, but the problem seems more of an air bubble issue as its dumping more water than usually into my expansion tank, def not burning coolant.

[d510addict]

Did you check the head gasket before you installed the new head? Some gaskets may have different coolant passage holes in them. Rare, but I've seen it.

I matched it up and everything seemed good. The gasket is a factory reccommended one from Nissan so I see no reason why it would be missing holes.

[d510addict]

I would also like to note this, with water flowing to my intake but having no where to go but the way it came, it seems like that would cause a lot of potential pressure/air in the line issues. Ive seen what air in cooling lines can do to an sr20det, could this be my issue? Because so far the thing is running consistently warmer even at night than what it was doing with the A87 head that had coolant ports.

 

Now to fix this I would need to drill out those ports. Can it be done with the head on? Or do I need to pull the head again?

[datsunaholic]

You can drill it with the head on, just don't drill too deep and have a REALLY good shop vac to get the shavings out.  Seal the intake and exhaust ports first too.