Monza cooling??

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Monza cooling??

Postby Gator » Mon Oct 26, 2015 3:06 am

What are you guys with the high out put motors useing for cooling? Not much room to do this! Im going nutts trying to figure out just whitch way to go. Can you show off some pictures under the hood of what you did? I wont to get back on the road with this thing!! I picked this car up cash as is and was told it ran 180 all day long !! What bull shit! Now I need to do some thing!!! Thanks!
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Re: Monza cooling??

Postby Smiley » Mon Oct 26, 2015 6:24 am

post some under the hood pictures and specs on what your car has for cooling currently.

Does it run warm while driving above 30 mph or while stopped idling in gear ?
Last edited by Smiley on Mon Oct 26, 2015 8:22 pm, edited 1 time in total.
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Re: Monza cooling??

Postby cjbiagi » Mon Oct 26, 2015 6:33 am

Here's a copy of something I wrote up awhile back:
There have been tons of tips over the years on cooling. There really should not be any issue with cooling while driving above 30 mph or so. Start with the basics, a good radiator ( I highly recommend an aluminum), proper molded hoses, a good mechanical fan with a shroud, make sure your cooling system is full of no more than a 50% solution of antifreeze along with a bottle or two of Redline WatterWetter, make sure your overflow system is connected and you have a proper radiator cap. Thermostats are always a controversy, I believe in running one since millions of cars use them and they don't overheat. An auxiliary electric fan is always a plus and adding some sheetmetal ducting in between the grille and radiator to direct all of the airflow through the radiator is a good idea. That will vary by make and model, but I added some simple sheets to help direct the air to the radiator and it did help. Also run a good air dam under the front grille area to create a low pressure area under the car as well as behind the radiator which will help promote air flow. That's pretty much the basics, after that you are looking at tuning the engine for the correct A/F ratio and ignition timing which can help. Try running full manifold vacuum to the distributor advance (you are running vacuum advance I hope) and see if that helps your situation since all engines are different. Doing all of this should help with 90% of any cooling issues. Granted the temp may still rise if you are stuck in traffic or God forbid, you are in a parade. There will always be a bit of an issue because of packaging, it's a small engine compartment with a relatively small radiator, but these things should keep you out of danger."
Clyde.........75 Monza 2+2
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Re: Monza cooling??

Postby Gator » Wed Oct 28, 2015 12:40 am

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This it what it was when it got hot on me. I drove about ten miles and then sat at a red light and a block further it started pushing water out in the over flow bad!!
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I was going to change to two 9 inch elect fans but was told this would not work.
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Re: Monza cooling??

Postby Gator » Wed Oct 28, 2015 12:49 am

Now I have the fans in the front to push air into the rad and was going to put the flex fan back on it and try to get a fan shroud to work but its so small in this area it looks like Im going to have a lot of trouble doing this.
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This is with the fans mounted in the front. I picked up a one inch metel fan shroud that I hope works. I have a 15 inch flex fan and the hole is 16 inches. very tight. I hope it lines up.
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Re: Monza cooling??

Postby Gator » Sun Nov 08, 2015 2:24 am

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So this is what I did. Made a cookie sheet into a shroud and added the two fans to it. The cut the area around the radiator out so it sits a little more forward. And hand made new top mounts to hole it all together. Wife mad about cookie sheet!!
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Re: Monza cooling??

Postby Smiley » Sun Nov 08, 2015 3:17 am

Your crank pulley is way too small, it should be larger than the water pump pulley.
Look for a deep groove 1975-1982 Corvette OEM 2 Groove Crank Shaft Crankshaft Pulley # 346300 or # 469558 they are 7.75" O.D. but the belt runs down in the groove so it acts like a 7" shallow groove.
even with electric fans your water pump is not circulating the coolant fast enough, your alternator may be going too slow at Idle to run those electric fans and charge the battery
your radiator and mechanical fan look fine.
9" fans may be a bit small as primaries, you may want to try the mechanical fan with the 9"s in front as helpers.
If you plan on winding your motor over 6000 rpm you should put deep groove pulleys on the alternator and the water pump as well.
With Don Hardy mounts in my 73 I can fit a 17" fan under the stock hood.

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Re: Monza cooling??

Postby cjbiagi » Sun Nov 08, 2015 9:10 am

The other problem with this setup is also the shroud....you are blocking much of the radiator with that pan (shroud). A shroud needs to be around the outside perimeter of the radiator not blocking the fins like this one is. The way this is you are only utilizing two small 9" areas of the radiator. Why did you you remove the mechanical fan? It looked like it fit ok. What you need is a shroud around that fan. A shroud should also be designed so that half of the fan blade depth is inside the shroud with about 3/4" clearance around the edge of the blades. This will allow the fan to pull the maximum amount of air through the radiator. A electric fan in front can help as mentioned, I have one but to be honest it rarely comes on since I utilized all the other tips I mentioned above. Good tip on the crank pulley, I did not even see that. Yes, it needs to be larger as mentioned. The factory setup overdrives the water pump slightly, your is way underdriven.....
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Re: Monza cooling??

Postby Choppachris » Mon Nov 09, 2015 6:29 pm

I'm thinking the crank pulley was under-driven for track use? Your car looks like it was a drag car in a previous life 8). Maybe they under-drove the pulley because they intended to run WOT at all times?

Here's mine, bad angle, but only pic I have with me here at work ;)
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Re: Monza cooling??

Postby EVL VEGA » Mon Nov 09, 2015 7:03 pm

When i bought the car the guy before me used it for mostly local night time street racing. He had a tiny steel radiator in it that just couldn't keep up with normal daytime street driving.
He also only had the body of a thermostat to act as a restriction with all the guts of the thermostat pulled out.
I drove it like that for less than a year and i couldn't take it anymore. I was constantly pulling over to let it cool down then drive some more then do it again.
I put in a generic (Summit brand i think) radiator with two side brackets i had a friend TIG weld on..working thermostat..redline water wetter..it already had a big electric pusher fan on the front..electric water pump.
Worked great after that. One time I drove it in the summer (100+ degrees out) 14 miles up a huge grade to the Barona 1/8th mile track. Raced it all day. Then drove it home. It never got over 210.
The electric fan makes it nice to cool it down..shut off the car but keep the fan and waterpump on.
Here are some pictures of the install. Not very good pics since i wasn't actually taking the pictures to show the radiator or fan setup.
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'73 Vega Hatchback (former Super Gas car)
406 SBC, AFR 210 Eliminator Heads, 9:1 comp, pump gas, 328RWHP/412RWTQ (old heads, no N2O 1/17/04), 6.86 @ 100.8 in 1/8th (No N20 9/4/16), Mike's Trans TH400 (reverse manual), 5000 stall, 12 bolt, 35 spline strange axles, 4.33 gears, spool, hipster transbrake, linelock, backhalved, Alston 3 link, 100 shot NX Hitman+ kit, LC1 Wideband sensor, 31x18.5 MT Sportsman Pros, "Plum Ugly"™ Purple paint.
"Pound to fit..paint to match"
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Re: Monza cooling??

Postby Gator » Wed Nov 11, 2015 2:56 am

Man thats tight!! How big is your radiator? Im thinking I need to check the timing on this too. He has a retarder under the dash that has three settings and I know nuthing about it. It might be giving me trouble too.
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Re: Monza cooling??

Postby Gator » Wed Nov 11, 2015 3:05 am

This is how its turned out so far. I made some hold downs for it to hold it all together.
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Now to wire it up and see how it works out.
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Re: Monza cooling??

Postby cjbiagi » Wed Nov 11, 2015 7:46 am

It looks nice but I still think that pan you are using as a shroud is blocking too much of the radiator. Time will tell.....
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Re: Monza cooling??

Postby EVL VEGA » Wed Nov 11, 2015 11:03 am

Gator wrote:Man thats tight!! How big is your radiator? Im thinking I need to check the timing on this too. He has a retarder under the dash that has three settings and I know nuthing about it. It might be giving me trouble too.

I assume this was addressed to me.
Yes it is tight but since it's an electric water pump and no mech fan nothing is moving near the radiator. Also the motor is bolted to the solid front motor plate so it doesn't' wiggle at all.
It's been about 10 years since i put in the radiator. I'd have to measure it to get the size.
EVL VEGA
'73 Vega Hatchback (former Super Gas car)
406 SBC, AFR 210 Eliminator Heads, 9:1 comp, pump gas, 328RWHP/412RWTQ (old heads, no N2O 1/17/04), 6.86 @ 100.8 in 1/8th (No N20 9/4/16), Mike's Trans TH400 (reverse manual), 5000 stall, 12 bolt, 35 spline strange axles, 4.33 gears, spool, hipster transbrake, linelock, backhalved, Alston 3 link, 100 shot NX Hitman+ kit, LC1 Wideband sensor, 31x18.5 MT Sportsman Pros, "Plum Ugly"™ Purple paint.
"Pound to fit..paint to match"
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Re: Monza cooling??

Postby cjbiagi » Fri Nov 13, 2015 4:52 pm

As I see it, the main difference between a H body cooling system and any other SBC powered car is just the size of the radiator and smaller engine compartment. Otherwise everything is pretty much the same. So having the most efficient radiator to offset the smaller size is a big plus. That along with making sure you have decent air movement with a lower air dam, good radiator fan, shroud etc should accomplish the goal. As far as the thermostat goes, how many of your daily driver cars, new or old, have a thermostat in them? My guess is probably all or most of them. Every new car made has a thermostat and they all cool great. I really don't think a having a thermostat is going to cause any issue as long as it is functioning properly. There are millions of SBC powered cars that are running cool with OEM pumps and pulleys, thermostats etc. The main thing is making sure everything is working as designed and you are not running around with a 10 or 15 year old half clogged radiator. Yeah, the smaller radiator and engine compartment do cause some issues but I don't think you need to reinvent the wheel to get these cars to run at a reasonable temp. The next point is "what is a reasonable temp". Most of us, including myself, probably try yo get them to run cooler than necessary and create our own limitations on what we think is acceptable. We see that magical "200" point and think we are on the verge of destruction. Truth is many cars are designed to run at that or above.
I do believe that going to a aluminum radiator is the way to go. Whether that means a rather expensive drop in unit as I have used or a universal one that you can make work, that is your best starting point. Then go with the basics that all current cars use, a good fan properly spaced, a good shroud, lower air dam, molded upper and lower hoses and maybe some additional ducting to seal the grille to the radiator. Stick with no more than 50% ratio anti freeze/water and a bottle or two of Redline Watter Wetter for good measure along with a properly functioning coolant overflow bottle, stick with factory V8 H body pulleys and you should be in good shape. This should work very well for a normally aspirated V8. If you are really cranking out some power or are using a turbo or supercharger you may have to go to some further extreme's. For most street driven V8 cars this should work well.
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