Lone Star Cooling problems

[undy]

I've got a LS427 with a fairly radical 428 FE in it. Since I've owned it the car has a tendency to run hot in bumper to bumper stopped or near stopped traffic. I was running the typical LSC provided Spall non-shrouded electric fan behind the Griffin aluminum radiator. Correct me if I'm wrong, but I think it's the garden variety 2ea 1" row Griffin. In the search of "the perfect cooling" setup I went with Flex-a-lite's new shrouded fan set up. It's the one that moves more air than any of their other models... so they say. Now the friggen car runs hotter at idle than it did before! It boiled over and blew steam all over everything this weekend and it was only in the 70s.. I'm also running am Edelbrock aluminum water pump. The fan's getting full voltage and running in the right direction. I'm at a loss... At this point in time I don't care what it costs I just need a cool Cobra..

[slithering]

I use a "Zirgo" cooling fan (3500 cfm) with a custom made shroud that encompasses the entire radiator. They make a larger cfm fan now. I also use Evans Cooling System coolant. This is a waterless non pressurized system that works great with my 427 sideoiler. I have no heating issues, and I'm in a rather hot summer region.

Chris

[trularin]

I had to up the CFM on my fan to 3800. I tried the 16 " multi-blade units rated at 2200, didn't cut it.

I also increased the water pump speed by dropping the crank pulley diameter.

May I suggest you check the rubber mounts for the radiator while you are at it, they wear away over time.

[rblong]

Pulley sizes

I have been posting my progress on the attached post.

Bruce

[rblong]

Ok, jumped over to this post because I have worked out all details with shrouds and such on another post (pulley size was it's name and I did some pretty extensive testing) and have made miles of headway. I have the 2350 CFM Spal. Want to go with at least 3000 - I am limited to single 16". I see a Spal that does 3000, but there are a lot of disclaimers on specs that make me a little nervous, BeCool makes a 3150 that they call a "radical" fan and actually sets off the radiator about 1/4 inch but they say still moves tons of air. I see Chris is running a Zirgo and they make a 3500, but it scares me when I see the cost at less than $100 bucks. I don't mind deals but this is 1/2 of anyone elses. Trularin you have a 3800 - what size and brand is it?

I guess I am trying to see what looks the best. Last thing I want to do it put one on that moves tons of air but goes out on me in the middle of nowhere!

Bruce

[CSX 4027]

Sounds more like timing than fans. Check your distributor curve. I would have the shortest curve possible and be running 18-20 at idle and 32-34 all in depending on your motor, the build, the compression, the plug readings etc etc etc.
A low initial timing setting like 10-12 could be your problem.

[trularin]

I was the validation engineer for the SSR ( yes, I work the GM stuff ), anyway, Bosch was asked to supply fans for the truck. One they sent was a two speed high flow fan with 3800 CFM.

It took four or five tries to get a mount and frame that would work, but it really makes a difference in stop and go traffic.

Look at this from a different point of view, if it doesn't over heat while driving and only while sitting, then you have ttwo places to start:

1. The water pump is not turning fast enough to move the hot water.
2. There is not enough air moving across the radiator to cool the water.

If it was radiator size, it would over heat more often and in a variety of traffic.


I hope this helps.

[Clois Harlan]

Dave has some very good points but I am inclined to think you need to check your timing and how lean your carb is running. Also, have you burped your water system. Do this by loosening your water temp gauge (cold engine) and starting up the engine leave this fitting cracked open until all the air in your system has purged and water starts slowly leaking out, then tighten. Also, how is your oil pressure?

Clois

[rblong]

Timing (bout 16 - 40) and oil is correct per Keith Craft (his motor). All flushed and air bled. Running on rich side (as I want). As mentioned I have pretty much worked out the bugs, but want to have a little extra air flow.

Anyone used any of the fans I mentioned?

Thanks
Bruce

[undy]

Spal's 3000 cfm fan is a "race only" fan, meaning open motor with a short operational life. I talked to Spal tech and they were emphatic about not using it for the street. I'd heard that Zirgo's 3300 cfm (I believe..) is extremely over rated. I lot of fan manufacturers post exagerated "free air" ratings. The rubber meets the road when you put it behind a radiator and the negative static pressure increases dramatically. The hi-flow fans usually fall on their face then. I wish all the manufacturers would publish the fan curves for their fans. Another thing to consider... Typically when you up the fan cfm you usually up the fan(S) amp draw too which might tax your existing electrical system, necessitating some electical work too.

I'm running Flex-a-lite's new shrouded 16" fan rated 3000 cfm plus. It has a nice black nylon shroud that was fairly easy to adapt to the LSC. I've never fed it with the proper voltage (10.9 VDC so far) so I can't make any claims to fame, or failure for that matter. This weekend I plan on installing my new 140 amp alternator and rewairing my charging/fan circuits. My 6 3/4" bottom pulley's supposed to be in today so that'll go on this weekend too along with the new 180 deg hi-flow t-stat and the water wetter. I'll post my results after..

Dave

[undy]

"Phase one's" done and at least I've got an electrical system that's up to snuff. Before with the car running at idle I was getting 10.9 volts at the engine fan and 11.9 volts alternator output. I'm now running 14.2 volts at the fan w/ the fan running and the car idling. The alternator output is also 14.2 volts. I've not run the car up to temp yet as I broke the cap tube on my fan thermostat. The things done today are as follows:

1. Removed March's 5.5" lower pulley and replaced it with an OEM 6.75"
pulley. The result is increasing the water pump speed from 8% underdriven
to 12% overdriven.

2. Replaced the alternator with a new 140 amp 1 wire hookup. It also
produces 80 amps at idle.

3. Ran a new #4 stranded copper lead from the battery to the new
alternator.

4. Ran a new #8 stranded copper lead from the battery to the engine
cooling fan.

5. Installed a new "hi-flow" 180 deg thermostat.

I've got to wire in a new fan thermostat, add the glycol and pour in some water wetter.

I'll post results after some high temps and prolonged idling.

Dave

[Tim Brewer]

All excellent points, as I am STILL fighting my overheating problems. I'm not sure if this is a problem or not, but I have my fan wired without a thermostat to run 100% of the time. I only have a toggle switch to turn it off if I need to.
What do you think?
Tim

[strictlypersonl]

Your problem will hopefully be solved by replacing the underdrive pulley with a stock one.

FWIW, If you have a the typical 22" x 19" size, the 2 x 1" core radiator is only rated to 400 bhp.

[trularin]

Dave, let us know what your results are.

Not that I have a heating problem, but I am interested in knowing what other people had to do to deal with it.

BTW, I have the 600 bhp rad. I think it is three rows.

[rblong]

I have the 22 x 19 3" thick. Since installing the inlet shroud I have no problems whatsoever at speed - will run 185 or so even at 95 plus temps. I installed the fan shroud and it will now maintain 195-200 in stop and go traffic at same 95 plus temps. The fan shroud does impede total air flow at speed so I at speed temps are not about the same as in traffic. I really think in my case the inlet is a must, but the fan shroud may not be needed if I had a higher CFM fan for traffic. I am really in pretty good shape now and don't have to eye the temp gauge like I used to.

Did I mention the inlet shroud is a must - it made the biggest difference of all!!!!

Bruce

[jwoodard]

Bruce,

You can improve your airflow at speed by fabricating small (say 2" x 3") air passages in your fan shroud. Place them close to each corner and attach a flap over each of rubber or some other pliable material. At speed the flap opens by air pressure against the flap and allows more air to flow through. At idle or slow speed when your fan is on the flap closes and causes all the air to be pulled by the fan. Hope that makes sense.
I had a similar set up on my Lone Star as you have fabricated and my fan shroud had those little flaps. Here's at picture but you really can't see the flaps.
After doing the inlet shroud and fan shroud I never had any heating problems and ran under drive pulleys.

Nice work with the aluminum!

[392cobra]

Great that you chimed in on this Jim.

That is a neat idea about the air flow hatches.I had forgot you had done that.

Finally got a inlet shroud template made this weekend.

Bruce is using milled aluminium.What was yours made from ?? Thickness ?

What make/model shroud and fan is that ?

[jwoodard]

Fred,

I'd like to take credit for those little suckers but they were part of the shroud when I purchased it. I bought the fan and shroud combo from Vintage Air in San Antonio. Here's a link to their online catalog:
http://www.vintageair.com/catalog.asp
Look on page 70, part number is 34317-VUF. CFM rating is 2700.
The dimensions are just right for the Lone Star radiator by turning it sideways and doing some real minor triming.

I fabricated my inlet shroud from a piece of aluminum that Lone Star had sitting around and I don't recall the thickness. It was brushed and I just polished it.

[rblong]

Come to think of it my boys 69 Camaro Griffin shroud has them also.

[392cobra]

Undy,
Were you able to get the thermostat wired in and check out the results of phase one ?