just to hot

[dillon_94]

our motor was running hot like 240 under caution but cooled down some while racing and now im going threw the whole cooling system to make it not so hot. what should be the first thing to do? well other then get a 4 blade fan and not the plastic p.o.s. no stat just a restricter, i think 30% under drive pulleys (water pump is bigger) and a stock pump that had every other fin cut out, (used this kinda pump for two years with no problems)

where should the fan shroud stop? ive heard have the fan 1/2 in and 1/2 out and ive heard have the shroud over lap 1 inch.

also after the main we had the car idling and spraying water in the radiator to cool that down and noticed the headers glowing red,

the motor is a little 327 with camel hump heads 11.5-1 with a holly 750, not sure on the jets but the air bleeds are turned out 1.5 turns if that matters, in a dirt modified
Thanks

[AmickRacing]

Step one, make sure the radiator is clean. You can take it out and lay it in a swimming pool (or other large water holding device) and let it soak a while, then gently "tap" it against the bottom. You'd be amazed how much dirt these thins can hole even if you spray them out at the car wash.

If the radiator is getting old (couple seasons?) I'd consider just replacing it.

In a late model, ducting from the tip of the nose to the sides of the radiator to help guide the are through it really helps. Not sure how much you can do on a mod, but anything to help block the sides and force the air through the radiator will help.

As for the shroud, if at all possible making one that's a smooth transition from square to round is the best, this reduces turbulence, a regular box one is probably better than none, but they have their flaws.

I always shoot for around half of the fan in the shroud, with 1" clearance around the fan to the shroud. I don't think you'd notice much difference with how much of the fan is "in" the shroud, long as there's some in there.

For what it's worth, I'm running a WISSOTA late model motor, steel heads, with the front ducted, a shroud, 180 deg t-stat, and one of them plastic flexi-fans (don't like it, but they aren't my favorite either), and I have a heck of a time getting up to temp. Currently I've got around 3/4 of the radiator blocked via some plastic on the shaker screen and it barely gets to 200 when it's working hard.

Here's a pic of my shroud btw.
https://fbcdn-sphotos-a.akamaihd.net...92759411_n.jpg

With the headers glowing, you likely have some other issues going on. I'm not great with motors, but glowing headers I believe is usually caused by improper timing (getting the burn to start too late in the stroke and continuing to burn out the exhaust), or possibly a very lean condition causing higher exhaust temps.
Might double check the plugs and look in the exhaust ports to see how things are burning, and double check the timing.

[sj valley dave]

We run our pulleys with a 15% reduction turning the engine 8400 rpm, 4 blade GM fan, Adams water pump and you need the fan 1/2 in and 1/2 out...No thermostat or restrictor with a double pass (that's the restriction), have to run 4 strips of duct tape to keep heat in it on a 95-100 degree day...Glowing headers is usually a sign of retarded timing or too rich a mixture, causing fuel to burn in the header. If it was lean enough to turn steel glowing red, what do you think would happen to your aluminum piston? Melt down a piston...If it's still running I'd look at rich mixture/timing...