Keeping it cool

[-Nemesis-]

Max you really need to follow through on this:

http://lextreme.com/forums/showthread.php?t=4183&page=2

 

[-Nemesis-]

Some quotes from a very interesting Autospeed article I just found:

Air will only flow if there is a pressure differential. This is a really important point to grasp – air doesn’t pass through the radiator just because the car is moving forward. Instead, there needs to be a higher pressure in front of the radiator and a lower pressure behind it – that is, a difference in pressure.

So the airflow through a radiator doesn’t depend on the pressure in front of the core; it depends on the pressure difference across the core. IOTW, the air exit is just as important as the air entrance – if the air exits aren’t big enough (or the airflow doesn’t pas through them quickly enough), pressure will build up on the downstream side of the heat exchanger, decreasing the flow that’s occurring through it.

Article:

http://autospeed.drive.com.au/A_2159/cms/article.html


Which I think is 100% my problem, being so tight in there there's no way for the air to escape.....

 

[-Nemesis-]

About scoops:

Bonnet entrance vents – eg to an intercooler – are located and shaped to build-up a positive pressure on one side of the heat exchanger. For example, this Impreza WRX uses a very large forward-facing scoop to cause increased air pressure on the top surface of the intercooler. If at the same time there is a lower pressure on the other side of the ‘cooler, air flows through it. However, this in turn directs more airflow into the underbonnet space, creating an even greater need for a lot of exit flow capability.

So if you’ve added a bonnet scoop to pick up air – or you have enlarged the standard scoop – it’s quite possible that there’s a pressure build-up under the bonnet which is dropping the efficiency of your radiator, intercooler, oil cooler and/or air-conditioning condenser.

Get rid of that pressure build-up and all of the above will work better...

 

[Max Hardcore]

We have swapped the Hoses around a couple of days ago, and i will be testing over the next few days but i can say it runs much cooler now......
Thanks Nemises and Twisty, thanks to your keen eye i may be able to get an m90 under there seeing it cools now

 

[jcclures]

When I started my engine conversion I tested a few things one of which was I removed the thermostat and tested it by bringing it to the boil on the stove.
I am starting to think it would be a good idea to buy a good gauge to fit in my Nissan but test it against my thermostat on the stove, this would then give me a reference point from which to work from once you start to drive the vehicle.
I think that would apply to all of us that are using these engines in conversions.
What do you think?

 

[-Nemesis-]

We have swapped the Hoses around a couple of days ago, and i will be testing over the next few days but i can say it runs much cooler now......
Thanks Nemises and Twisty, thanks to your keen eye i may be able to get an m90 under there seeing it cools now

No probs mate. You certainly know someone who's good with the bling metal fab, looking good

 

[sideshow]

unless u have a gauge with numbers its useless

i got an alloy rad today shots on my old copper one

temp sat on 77 when driving doin 80 kph

then got up to 83 85 when stopped

that was this arvo

so i hope to test it on a hot day

but i also have a trd 71 degree thernmostat about 140 bucks

then i drilled more holes round the edge to get more water flow thru it

i will now buy the oil tmep sender to go with my device
which measures water/oil temps and turns on thermo fan at whatever temp i want

the old radiator is for sale if anyone wants it

its a tripple core with 2 thermos
plus ill throw in a 14 inch thermo for 100 bucks

 

[Rickfred]

G'day fellas,
Hey Sideshow, your Hilux engine bay looks great!!

Here is some ideas I have used that may help with cooling dramas.
I have run a 3 row, triple flowed "fine core" (flat plates for heat exchange fins that have 360 degree contact to tubes and the tubes are staggered so hot air from the front does not go directly onto the aft row, etc) using standard Hilux tanks in a 2wd with a Holden V8. Again not a cheap radiator, but I have had no cooling problems and have ran the same setup for 16 years in this car. I have used the same setup (execpt using alloy) in sprint cars with success. Very simple. The "fine core" is said to be up to 40% more efficient and triple flowing 15%. This thing does not get hot! I have a 188 deg thermostat fitted to get some temp into the motor! In Winter (Sydney) I have to block off a small section of the radiator otherwise the engine runs too cool going to work in the mornings, works well!

Another "old trick" I have used on race and street cars with an engine filling the bay right up causing hot air to "dam up" the engine bay is to fabricate a small lip and fit it under the aft lower edge of the radiator in the airflow under the car causing slight turbulence and therefore a low pressure area below the radiator sucking the hot air down and out under the car. No good in traffic, but helps when the car is moving. Manufacturers have used the same method for years. Check under the front of a HX for example.


I hope this helps some of you guys!
Regards,
Freddy

 

[sideshow]

from what i have come across most toyota gauges will read the same from 80 to 100 degrees
so i fitted a digital temp gauge
with my custom 550 dollar triple core copper radiator
it would get to 113 degrees on a hot day say around 30 degrees
cause i had no room i had a 10 and an 11 inch fan on my triple core

it did not work prperly but if i ran the toyota gauge it never got too hot
and never boiled

but with the digital gauge it got hot but never boiled

now with new alloy rad it wont go past 90 ish
this is with a slim line 16 inch fan and the alloy rad is not as big

the difference is

copper triple core at 10 mm per core thats 30 mm of cores
new alloy cor at 26 mm per core it has 2 so that 52 mm of cores

52 mm against 30 mm just doest compare
then u have alloy cools much better

so all i got to say is all these old school radiator shops are ok for std cars
but for minimal room and high performance alloy kicks butt


i can easily prove this cause i have a digital temnp gauge thats has an lcd screen with the exact temp

in a week or so ill order more of these gauges
and connect an oil temp sender to it aswell so i have water and oil temp

thats my 2 cents worth

 

[Rickfred]

I agree Sideshow, we had much better results in the Sprintcars with the alloy units. The old school radiator is still in my Hilux 'cause it still works. I triple flowed the alloy Sprintacar units to give a bit more margin as cooling a 740hp V8 being thrashed all night needs every advantage it can get. It was a simple matter of cutting the top and bottom tanks a third of the way across and welding in the baffles with the TIG.
For those unfamiliar it makes all the water flow through all the cores. Stops some water going into the top tank (or side inlet tank) across the cores and straight back into the engine. Old school trick, but works. Some builders do it for you cheap enough.

Thanks for putting up the dimensions of your alloy core. Can you please measure up the fan thickness as well (if is not inconvenient) and the overall thickness of the radiator and fan mounted? My Hilux 2wd is a '79 and the engine bay I think is a little shorter than yours. After 16 years it is nearly time to take the old girl off the road for some body tidy up and a fresh powerplant, hence my interest in the 1UZ set up. (The old story, that's a couple of projects down the way. Too much to build and a 36 hour day is required!!)

Also, Sideshow can you plesae put up a pic of your digital temp gauge when you have it. I am building a V6 powered Hiace work/travelling rig and am putting a dash in that actually will read info that is usable instead of "oranges & bananas"! I need to monitor the auto trans temp as these big fronted (hi-roof) beasts really heat the auto up. If it suits the dash it could be the go.

Check Ya!
Freddy

 

[sideshow]

i will try hard this week to order 20 of these units
and some extra oil senders as these dont come in the std kit

i just need some spare time to organise it

 

[nathan]

who made your radiator sideshow? i need one for mine and if yours cools it good, might as well get one, also what was a ballpark price?

 

[sideshow]

mr enforcer

he does awsome work

im not to sure on prices best to ring him

number is 02 97557844

i have limited room and it works better than anything else ive tried

i can even put back of bonnet down again

he told me to go alloy ages ago but i tried other things

my stupidity i didnt do this ages ago

i didnt want anyhting fancy or shiny in my engine bay but

i dont mind it now

the engine runs much better too

 

[nathan]

i think ill know what you mean by limited room, my bonnet will be almost 3 inch closer to the motor than yours due to channeling, ill give them a try tomorrow, should i just ask for an alloy radiator to fit a hilux and cool a V8? or does he know you, so i can say one like yours?

 

[sideshow]

just tell him similar to sideshows radiator

 

[Max Hardcore]

Hey sideshow nice radiator.
I might have to get one of those trd thermostat's.
Mr enforcer sure does nice work doesn't he, what temp do you have your thermo's coming on?

 

[sideshow]

yer he is very good welder

the trd thermostat is around 120 trade

my thermos come on at 86

 

[nathan]

sorry to go off track, but sideshow, you use a CRS sump correct? how did you make the dipstick work, as my sump has no provision for a dipstick, and im confused, dont wanna drill holes in the wrong spot

 

[sideshow]

on the other side of the enigne at the back there is a plug

just punch it thru and it will fall thru to the bottom

then swap over the dipsticks

then silicomne the orig plug and hammer it in the orig dipstick hole

 

[nathan]

is there any chance you have a picture?
i had a rear sump originally, and i think the dipstick hole was part of the sump