My car is doing much better on temps. I still think there's an issue with the oil temp, but it's not bad, not bad at all. I replaced the radiator and put in a 180* thermostat. I cheaped out and went with the stock replacement. But, it looks like the new stock replacements are about 30% thicker. So now at highway speeds even pushing it, the coolant stays at about 185*. In the city, at a light, it will climb, not real fast, but it goes over 200*. The coolant will eventually get hot enough to trigger the fan, if it sits and idles long enough. Seems normal to me.
The oil temp climbs on the highway when pushed, got up to 210* on a 20 mile trip today. At idle, the oil temp will drop. I was pushing it in the city on the way home, after I got off the highway, got the oil up to 217*. Not sure what, if anything can be done for this, or if it's even a problem.
My next step is to buy a PCMFORLESS chip and have the fan come on sooner. What do you guys think, 210* coolant temp for the fan?

Here is the new radiator with the old one:


And here's what came out of the vaccuum cleaner:

them leaves will cause all sorts of issues... seriously... you have half a forest in there.

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Had!

The temps I describe are post leaf removal. What do you think, is 210* a good temp for the fan to come on?

I usually avoid the threads on temps, oil, octane, but I will give my opinion. The temps you describe are just fine. I just can't justify the cost of a "chip", and adaptor board to cut on the fan 20* degrees sooner. These temps drove me crazy for a couple of years too, now with a new OE radiator like yours and even with a 195* thermostat it's fine. But if you do the "chip", I wouldn't go any lower than 210*

Joel

I know I'm obsessing, but I've always thought heat = bad. The people at PCMFORLESS have a product to sell, so I know I have to take what they say with a grain of salt. But they say even for my basically stock 87, the chip will make it run better. My big "mods" are a catback and cut airbox. The fan turn on is a bonus.
PCMFORLESS is generally well regarded, so I factor that in when listening to what they say.

IMHO you never needed a new radiator. The debris was causing your problem. I don't think you need a PCMforless chip. If you want the fan to come on earlier you can get one of those midamerica/ecklers type switches or use a lower temp switch from gm that turns your primary on/off at a lower temp.

Matthew

Just a lower temp switch will do it, no change to the computer?

I tend to agree with Matthew about the radiator.
Yep, just a 210 temp switch, you'll be fine.

BTW, Summit probably has better priced on the temp switch than mid/eck.
They also have a programable one that reads the external heat on the radiator fins and can be set to any temp you want.

Temps sound fine. The oil is barely getting warmed up at 217F. I'm always up at those temps on the street with the stock radiator. The coolant is supposed to climb past 200F. I'm surprised it didn't climb up to 228F to trip the fan on, even on a cold day at idle.

Basically until there's airflow through the radiator, coolant flow alone won't cool the car off, except on the coldest of days. So it'll keep warming up until there is airflow, whether it's the fan coming on or the car starts moving.

Without the Z51 oil cooler, the oil can easily run 30F+ warmer than coolant if you drive it hard.

People say the C4 runs hot, but I say they're full of it and have no concept of what hot is. I had to abuse my car badly before I ever tripped the high temp warning lights. The car won't even boil over until past 265F, so you have plenty of room for error. Now, if the fan(s) are both cranking and the temp doesn't start dropping, I'd be worried.

I contend that's it's virtually impossible to overheat a stock C4 with a halfway maintained cooling system on the street.

I am with everyone here... The temps are fine.

You have to realize that the metals used in modern engines are designed to expand at set rates. If the temps are messed with too much, those rates can be effected.

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Yes. I don't know if you/your year had both a primary (puller) and secondary (pusher) fan. You can get a gm switch to turn on the primary earlier or an aftermarket one to turn on the secondary sooner. I personally have the secondary fan turn on installed on my car by the PO. Temps almost never climb over 210 but it annoys me the fan is always on.

Matthew

Ok, thanks all. I'll quit obsessing over the temps. I'm just one of those particular kind of guys who wants things "right". It's a flaw, because "right" is subjective, and often a moving target.
I'll look into the switch, and compare the price with the chip. I guess I was justifying the chip with the fan on issue. I still feel like I'm missing something without the chip. I know, a chip won't do much for a stock car, and I believe it, for the most part.

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Yep

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On your 1987, the main fan is controlled by the computer. Only the auxiliary fan, if so equipped, is controlled by the aux fan switch in the left head. Without additional wiring you can't change the main fan temps with a just a switch change. I don't know what switches or switch kits you might be considering. 210° for the main fan to come on is a very good choice. I wouldn't go any lower. My fan only comes on in heavy stop and go traffic or idling. I have the factory installed radiator core. Driving down the highway below 90° ambient temps my car barely hits 180° with a 180° stat (too cool, really). On the highway the oil eventually tops out at 230°, cruising. I also have a manual fan switch for track use.

RACE ON!!!

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Thanks for the info. My 87 only has 1 fan. So, I guess I'm back to a chip or a manual switch to get the thing on at 210*?

The manual switch is easy and costs $5, $8 if you want an LED indicator n the dash.

I have a manual on my LT1 but rarely use it.

If you want to do anything, go to Moates.net and buy the kit with 2 chips and an adapter for $55, then buy the burn 2 chip burner for like $80, then download TunerproRT for free. You can make any changes you want, and you will have less money in it than if you buy a pcmforless chip. Then in the future if you mod more, you can change things for free instead of paying again.

Your temps are fine, both oil and water. I didn't see where you said exactly what temp the main fan comes on but 205 is what I like with a 180 stat. If yours comes on at 210 to 215 then I wouldn't spend any more money on it. If it don't come on till 228, although not bad, I'd buy the stuff and make the change in the chip. I'll walk you through how to do it.

personally I like the temps a bit lower. Either way, you need to make yourself something like this :
[IMG]http://i39.tinypic.com/2ufennp.jpg[/IMG]
[IMG]http://i43.tinypic.com/smf6nc.jpg[/IMG]

^^Works for Mice as well.

Nice work mseven. I'll post up some pics of my debris screen too when I get home.

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Gee that's fancy.
I can't find any pictures of mine right now. But below is a pic from when I cleaned out my rad area. For the screen I made a cardboard template first, it was easier to trim to get it right. Held it on with a couple zip ties and some factory screws. Painted it black to blend in. Just chicken coop wire from HD. Total investment, about $6.00.

Matthew

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