40s V8 cooling

[Fieldsy]

I have been looking for something about this for about an hour but can't find anything even tho I am sure it has been done befour so anyway. I have just got'n my 40 back with the 308 in it and havent even driven it yet but I have some concurn about the ability of the stock raditor's ability to cool the 308, It has a elec fan from some jap car on it because the holden fan is way lower than the 2f's one was. and I am asumeing it wont cut it. but am I wasteing my time with the stock rad? what are the other blokes on here with v8's in 40's cruisers useing and how does it work?

[dumbdunce]

40 series radiator is pretty hardcore, they are a big area and have 4 rows of tubes. if it is in good condition it should do the job.

to get the best airflow through the radiator, go for an engine driven fan and a fan cowling that forces maximum airflow through the radiator instead of around it (which is the case when the cowling is removed). it doesn't take super sheet metal skillz to build a decent fan cowling.

electric fans just don't cut it, the motor in the middle of them always blocks airflow to a significant chunk of the radiator and they just don't move enough air when the motor is working hard. they are good when you're trying to maximise power and/or minimise noise and there is HEAPS of radiator to spare but for best cooling efficiency an engine driven fan just can't be beaten.

cheers

Brian

[Fieldsy]

I would like to use a motor driven fan but it is way too low. like the hub is only about 4 in above the bottom of the raditor.

on a side note I am very happy with what you said about the rad

[dumbdunce]

I would like to use a motor driven fan but it is way too low. like the hub is only about 4 in above the bottom of the raditor.

that's pretty gay :(

if you have to go electric, and it sounds like you will need to, try for a fan that has a taller, narrower motor, so it covers less of the rad with "dead" space, and the rules about cowling still apply - try and rig it so the fan isdrawing air through the whole radiator, not just across the area of the fan.

also make sure you run the correct temp thermostat.


cheers

[the_smoo]

my 308 conversion was done by someone else, but i can take some pics of the setup if you like. it runs the motor driven fan, but doesnt have any cowling..

[Fieldsy]

yeah that would be cool I would like to see how the fan lines up

[Daisy]

modified AU twin thermo fans?????

they'd do the job wouldnt they?

[Shorty40]

253 with standard radiator. Motor driven fan. No cowl.

However, the engine is so far back in the bay that I have nearly 12 inches in front and behind the radiator. Fan lines up with the radiator fairly well.

Engine runs nice and coooooool

I can get a pic if you want.

[the_smoo]

heres some pics....

[ORSM45]

im running std 40 series radiator, works fine. if you want extra cooling put a 60 series radiator in, they are a bit wider.

does anyone have the width and height measurements for the ford fans?

[dumbdunce]

if you want extra cooling put a 60 series radiator in, they are a bit wider.

but aren't they shorter? I think the frontal area works out about the same?

[Fieldsy]

I have herd about useing AU fan's and I recall seeing something about it on here but I can't seem to find it ( at work so must surf fast ) Arnt they pritty cheep and work well? cant find it

Smoo my fan might sit a bit lower I'm not sure and like you shorty my motor is way back in the engine bay so maby I am just over reacting and a fan on the motor will do OK after all.

[ORSM45]

if you want extra cooling put a 60 series radiator in, they are a bit wider.

but aren't they shorter? I think the frontal area works out about the same?

yeah tiny bit. but the 60 is still bigger. off the top of my head, i think the 40 is around 350sq. in.

the 60 is closer to 400sq in.

if you want real cold get an international 7 core. mark from JPC had one of them in his old V8 40 series.

[Mechman]

i have the same setup as the smoo... no cowling as yet, but i am thinking of making one... just coz i can.
running good qual coolant makes a huge difference too. check all the makes and you will find a huge diff in the boiling point. i uses 70% mix and it runs a treat.

just as aside.. smoo... what carb are you running?

my fan sits in the same place but i have a 253.

[mudtoy]

I've found that if you have to go electric, the VP/VN thermo fans and cowls are an almost perfect fit for the 40 radiator and they seem to move good air.
My 40 with a mild 308 ran sweet on this set up but once I stroked it she needed more (so to speak). So in went a 70 series radiator...only a little wider but much deeper. That did the trick, but in the search for cooling even more HP, I am now looking at a 60 series radiator.

[Fieldsy]

Funny thing hapend this arvo. I was in the local repco and their in their shop was a brand new 60s rad for $200 . yes It's still their. Mudtoy that's bad new's my 308 is allready stroked and bord out 80tho

[revin]

If your worried about Electric fan motor blocking the front of the Raditor make sure you get 1 that pulls air thru not pushes,Also run a bypass switch so you can lock the fan on all the time instead of running just off the thermostat switch.

[ORSM45]

Funny thing hapend this arvo. I was in the local repco and their in their shop was a brand new 60s rad for $200 . yes It's still their. Mudtoy that's bad new's my 308 is allready stroked and bord out 80tho

whatever you do, dont get a repco thermo switch, its a pile of junk. (i think ive said this 50billion times now.)

what revin said is right. put a switch to over ride the thermo switch.

fieldsy just move to melbourne, it'll never over heat

my electric fan could run 10-20 degrees under normal operating temps if i left the fan on all the time. (depending on climate conditions) it survived a 37 degree day, and my car is black.

[mudtoy]

might sound funny but for some reason the chevs hold their temp better than the holdens when whacked into fourbies...

[Fieldsy]

fieldsy just move to melbourne, it'll never over heat

Moveing to Albury at the end of next year does that count

[Raymond Spackman]

If your 308 is bored out 80 thou the walls of the bore would nearly be nonexistant. has it been resleeved? The most I would go on a 308 is 40 thou. I was told by an engine builder with bores too thin that will cause heating troubles for a start. Have your bores been sonic tested for thickness?

[Fieldsy]

The walls are very bloody thin yep I know this dosent help my cooling and It cant be rebored out anymore but the motor didn't cost me anything so even if I do kill it I am still ahead It also has stage 2 heads, flat top pistons, a mild cam, stroker crank, bigger mains, and electronic dizzy, I have just replaced all berings, rebuilt heads, new rings, rockers, fuel pump, oil pump, water pump, timeing cover, timeing chain, cam, and all hoses filters and clamps.

I hope it keeps running for a while

[DAZ]

fieldsy just move to melbourne, it'll never over heat

Moveing to Albury at the end of next year does that count

I was born in Albury and have spent most of my time there i built my truck in Albury .I run a stroked 350 chev and was told the larger late model radiator will cope if you use it as a car it will but driving it hard in mud and hills and your on the edge get a little mud in there you won't keep it cool once a chev gets hot it will stay hot as there is a lot of steel . I lowered my radiator to get the fan closer to centre and the fan was that big it went past all 4 sides of the radiator with a cowel i also fitted an engine oil cooler which helped . In my truck it never boiled but always ran hot when put to the limit .In my opinion the standard radiator will not cope on its own with a 350 i agree engine driven is the go but you need to lift its cooling affeciancy buy 25% there are many ways to achive this .

I have since changed my truck and am nervous as to weather im going to have more probs than b4 ill no in a few weeks . I am now running an 80 serries radiator ( alloy core ) and the ford fans you mentioned if you still require the measure ments request it on my thread to remind me . If any one won'ts some i know a bloke who is selling some new he never ended up useing .

[vraamm]

i have a 350 in my shorty and have had some cooling probs in the past. i am currently happy with cruiser radiator but will consider getting something wider in the future. i have a tighlty fitting shroud with the fan blades half in and half out of the shroud (supposed to be the way to go). I ran an electric fan for a while (a big davie-something or other?) that turned on at whatever temp i wanted but that was real crap. now have a chev viscous hub with an EA falcon 10 blade fan. works a treat even at 35C, 120km/hr or going hard on the beach. be wary of getting heavy duty radiators as anything over 4 rows usually means that each row is not offset so efficiency is lost.