Took the Astre on its inaugural drive today!

[v8astregt]

Overall not bad. First I had a problem with the trans. Fluid was a little low, but it was still wierd. Well after I reconnected the vacuum modulator underneath, that was good.



Overall, I'm very pleased with my new setup. It runs like a bear, and sounds great!


The only problem I had was that it ran a little on the hot side. I guess it should be fairly hot being that it is 108 outside. I thought the custom brass 4 core would have been enough, but I guess not so. At some times during my brief drive the temps reached upwards of 230*, a lot hotter than I'd like.


So I'll be paying close attention to the "radiator" thread in one of the other sections to say the least! I would like to see who all installed a universal radiator, since I'd rather spend some time to make a $200 universal radiator fit, than spend $500 on the same part, but "bolt in".

[HotfootGT]

Congrats.

Check for airflow to the radiator. You have a lot of restriction now with a bigger hotter engine than stock. You may need to fab a small scoop under the bumper to direct air into the radiator. The stock Astre grille opening is rather small. Also a shroud around the fan would help pull air through the radiator instead of around the sides. look at ways to vent the engine compartment too!

Good luck

[djv8ga]

Josh...I'm surprised you could drive it at all in this heat. 230* in July...Not bad IMO.

[DoozCoop]

When I bought my Vega, the previous owner said he had issues with it running hot (220f after each run), so I installed an electric fan from a beretta in front of the radiator to push more air through it to cool it better. That helped a little, but it still ran kinda hot so I figured it was time for a new water pump. When I had it apart, I noticed the arrow on the fan...and realised the electric water pump motor was turning counter-clockwise (the wrong way). A quick call to Moroso, and they assured me it could be hooked up either way without ruining the pump motor. I reversed the 2 wires, and voila - it stays near 180 now! I use the beretta radiator fan after each run, and it cools down really fast now between rounds.

[heinz057]

josh are you using the smaller water pump pulley? i'm using the smaller monza w/p pulley(5") and crank pulley(7.75) with a 3 row rad it never gets above 200 even in traffic with the temp above 90.

[v8astregt]

Thanks for the replies!

I drove it to work today (.5 miles from home), and of course that was fine. Then after that, I drove it to the Chevron to fill it up with gas, which was 2 miles away. The drive there was great... stayed at 200*. Filled her up. Drove 1.5 miles then the temp started to rise. I had my electric fan going, and even had my hood popped up in the back. About .5 miles from home, the temps started rising all the way to about 235 right before I shut it off. Quite hotter than I wanted.

I'm sure the TH-350 and 3.73's don't help = 2500 rpm cruising. Maybe I'd have to change gears.

I would like to build an air dam to route air, but I'm thinking I would like to get a radiator that would run much cooler and THEN build airdams. I don't want it to be "borderline" cool.

I'm gonna do some measuring after it cools down a little. I would like to see if I can get one of the $200 Griffins to work, I would install one that hangs down somewhat, but I would think that even though some of it would be blocked by the core support, the added capacity would help a lot. I don't think a nice, properly mounted aluminum radiator would be that bad hanging down a couple inches, especially once I get my front valance.

And there's also a 3000 cfm fan I saw on Summit's site. The fan I have looks to be more the 1500 cfm type. Maybe that will help.

What I do have is a Summit high flow water pump. BUT I have a 180 T-stat, which in hindsight, I shoulda done 160, or left it out entirely.

And I like the idea of the smaller pulley, definitely makes sense. I don't care about power loss or whatever.... what does difference does power make if I can't even drive it!


Sorry for the lengthy response. I just sucks... I was all ready to drive it, and I thought I was done. Well, more $$$ to spend!

[SunbirdMan]

The factory V8 waterpump pulley overdrives the water pump by about 40 percent. From what I can figure, this is about the highest overdrive you'll find on a sbc. So, why did GM do it? Smaller radiator requires a higher pumping volume and higher fan speed? I don't know, I wish I could tell you that a smaller waterpump pulley will fix your problem. But that's where I'd start.
Don't run without a thermostat. The restriction raises the pressure inside the engine thus raising the boiling point of the coolant thus preventing steam from forming in the heads. Or so I've been told.
That's a beautiful Astre you got there. Do you ever get tired of hearing that?


Roger

[DoozCoop]

One other thing you may want to check - is your top radiator hose higher that your radiator cap? If so, maybe you have air in your top hose, causing no or little coolant flowing thru the top of your system. That would mean no coolant moving past your sending unit. Jeg's or Summit sells inline radiator caps, which is a tube that you install at the highest point in your top hose. You cut the hose at highest point, install the tube with 2 hose clamps. It has a radiator cap mount attached to it - so you take that cap off, fill it up, and no more worries! here's a link to what I'm talkin about. Hope it helps - it's a relatively cheap fix. http://www.jegs.com/webapp/wcs/stores/s ... ryId=10603

[danarmstrong]

Hey josh,
In my 76 Monza I was having overheating problems and I bought the universal radiator you are talking about. It is the 2-1" row aluminum griffin I would have to check the part # if you would like me to. But it fixed my overheating problems, I have a 14 pusher fan on it for heavy traffic and you can turn it on and watch the temp fall, I live in South Alabama where it gets really hot too. the uviversal was a littel large at the bottom but a little bumping with a rubber mallet and it slips right in. Good Luck,, BTW I don't know a lot about your car but mine is only a bout 275 horse , my 77 is 450 and it has a dual 1 1/4" row griffin and I am still fighting overheating with it, I just haven't had time to try a few things,

Good Luck
Dan

[v8astregt]

SunbirdMan- no I don't get tired of hearing compliments! Actually today was the first time anyone outside my friends and family saw it... it got LOTS of attention! But I will surely find a smaller pulley soon.

And the more I find out, I realize I'm probably best to run a Moroso free-flowing 160 degree type thermostat.

And my top hose is higher than my radiator cap, but I did check that, and there shouldn't be any water in there, but I'll probably add that cap in when I order more parts from jegs.

As far ignition timing, I don't know exactly. It's an MSD Pro-billet so I'd have to check on what springs are on there and such.

danarmstrong- now you've got me worried! Your 77 has 450 horses and runs warm with the Griffin? Well mine is 440, so that's close enough. What else is in your cooling system?

And I do not have a front valence right now, since it appears Vegamods' website is down for maintenence, so I'd have to find some way of contacting them to get one. Then I need to find the black flap.

[heinz057]

you need to have that lower flap to have the air flow up into the rad at cruse speed also go to summit and check this out BRA-3500-01 i also have this in my w/p. check the t stat, make sure it is good. try to find the Moto Rad Fail Safe t stat if it fails it fails open.it seems all these little things should help you

[DoozCoop]

Good suggestion but that probably dosent effect coolant flow as you suggest, as all v8 monza's came from the factory with an upper rad hose higher than the cap.

if you have air trapped in the hose, coolant won't flow - quite common - I saw it often in the 8 years that I worked at East Syracuse Chevrolet. usually in heater hoses, but can happen in radiator hoses as well, have to bleed out the air - Just as I have to do in mine, which is higher than the cap...and it's a pain to get the air out.

Locates filler neck at highest point on cars with low-mount radiators to bleed off air.

- from Jeg's catalog for inline radiator caps (Jeg's brand)

It provides a positive fill point to get all the air out of the system and uses a standard radiator cap.

- from Jeg's catalog for inline radiator caps (CSR brand)

quite common indeed!

[heinz057]

josh check this out
http://www.geocities.com/g_wellwood/automotive/v8vega.html

[dumbcajun]

Try putting the cooler fan in back of the radiator, sucking instead of pushing. Elcetric fans generally work better sucking.

[danarmstrong]

Well with my 77 I have had it a while but haven't had time to mess with it in a year or so ,but I have the 2 row 1 1/4" griffin in it and a csv, or crs not sure electric water pump 36 gpm, and a 14" 2800 cfm fan pushing so I don't have enough air flow but I have a motor plate and I only have about 1-1/2" from the pulleys to the radiator. So a puller fan will definitely help if it will fit. I am planning on moving the radiator forward one day so I can build a shroud and have dual pullers on it. I am running a 165 thermostat also , have tried no thermostat, restrictor broken stat , and a regular stat and haven't seen much difference so far, my timing is locked out at 38 degrees, w/ a 60 over small block 350 , theres part of my problem,
Good Luck
Dan