Hey all;

I have searched the forum a bit and a found a few topics that cover temperatures, thermostats and the like, but most of them are so hijacked that the final answer to me is lost in the scuffle......

So I have a couple questions here regarding my L98 1987 Corvette Convertible. it is an 8 / Y series engine.

(Background) MANY SBC motors, love horsepower, reliable engines, tuning, Building engines, trans, paint body etc........

1. Is it it bad to put a 180 thermo in the car? My thought is that although Chevy originally designed it to have the 195 thermo in it (I believe to assist with emissions issues) it just runs too hot at 210 plus when idling. NO SBC I have ever had likes that kind of temperature at really runs optimally @ 180-190.

2. In conjunction with my above query, I would also like to go with a lower temperature fan switch. (about 195-200 on to 185ish off)

Is this so bad to do? Will it mess with the ECU? I suppose I am a creature of habit from long ago, but I just can't get over the higher temps and want to change this........

I will readily admit I am no professional with the "Newer" computer controlled engines..........so here I am "asking before prying/trying"!!

also one more question..... please....

Have any of you tried the Auto Xray 7000 model yet? I have a line on one for a really good price and see that it live streams, prints, up loads, has definitions, makes toast, etc...........

Thanks a bunch in advance guys, and as usual, I genuinely appreciate the positive feedback........

Don

P.s. this ain't my last question!!!!!

 

I'm going to be cool here. These cars are how many years old now? and they were designed to run with 195 stats and a lot are still going strong.

Do what you would like to do if you think you are better then all the GM desingers out there go at it.

The fans are set to come on at 228. There is nothing wrong with that again the way it was designed.

As far as any other SBC running that way or getting the most out of it. If it had a 195 stat in it and had a clutch fan it would see 230's at idel untill the clutch fan engauged fully. to bring it back down. the same elect fans do today.

It is you car do as you please. Not trying to be a smart a@@.

 

The C4 is designed to run hotter than some other cars and it's done to help with emissions.

As far as what you see for temps, you might check to see what amount of debris is clogging the front of the A/C condenser and the radiator. All of the air for engine cooling comes up from under the car (that's why they are called "bottom breathers"). Get the condenser and radiator clogged up with debris and the radiator won't be able to cool the engine properly. Regardless of the thermostat installed. The 'stat temperature value is simply a temperature when it's fully open.

You can also look thru the radiator shroud to see what's between the condensor and radiator. Use a garden hose to flush out junk that is caught between the tubes and the fins. I'll bet you'll get a ton of garbage out.

Another thing to consider is the age of the car and the miles on it. After years of coolant passing thru the tubes, they do get thinner and lose their ability to properly transfer heat. So maybe a replacement radiator is something to consider. A lower temp opening 'stat won't help if the radiator cannot cool the coolant.

Also, it may be time for a complete coolant system flush and hose replacement. If the hoses are original, you may have a hose partially collapsing and cutting the coolant flow.

I'm jut not a fan of a manual switch or a replacement ECM chip that changes when the fans come on. My 87 never hits more than 200 in street driving and I don't even see much more than 210-220 during summertime track days.

 

I bought an auto xray 7000 recently. It didn't work quite right and I could never get it to communicate with my PC. I traded emails with their technical service for a week then gave up and returned it to amazon.com.

Oh, as you shop for a scanner read the fine print. Most will only stream live data for OBDII & our '87s are OBDI.

 

Hooked;

Well, In all honesty I have to say it does strike me a bit smart alecky...(forum rules prohibit a better answer than that!) I don't claim to be smarter than GM's designers, as a matter of fact I did plainly state I am not a pro with the newer computer controlled cars.........Hence my question.....

As far as the design, that's great......it was during a time when emissions concerns ruled the day before technology caught up and horsepower no longer suffered.

Text communication is funny; you mean one thing yet it seems a bit harsh or rude per se' to the receiver.

As for an answer? well, it really is not there; basically just a few statements that don't give me the why, or real facts to base a decision on.

Thanks all the same.

C4;

Thank you for your input, I will check those items out and report....

3D87C4;

Thanks for the tip........ the one I ordered does pull live action like the same brand 6000 model........just takes a moment or so.....here's hoping.........

 

180 wont hurt anything also a fan of lower temps.
Gets hot as hell in the summer here so its 160s in all of them with fans on sooner. Never an issue wirh emissions. Flame suit on

 

I've been running the Mid America 200 degree fan switch with great success. Turns the fan on at 200 degrees and off again at 185.

http://www.mamotorworks.com/corvette?frame=1.944

If you get a low temp fan switch just match it to a 180 or lower thermostat.

Otherwise if you have a 200 degree fan switch and a 195 degree stock thermostat the fan will run too often because they will be fighting each other. They are too close together.

You neeed to space them out with a 180 or 160 thermostat to keep the fan from running too often.

On a single fan car the MAD switch allows you to go back to stock if you wanted by simply disconnecting it. The stock setup takes over again at stock operating temps. Snap the connector back in and it's low fan temps again.

I've been running mine for years without any problems. Car runs great and have never failed an emission test because of it. When I used to use my car for slow moving local parades it did a fantastic job of keeping my temps in check in hot weather.

 

Cuisinartvette, Pacer;

Thanks......I appreciate the info.....Ill look at the link to check it out....

Have a great day.........

UPDATE: I checked out the Mid America Motorworks kit.......... looks nice...other nice items there too.... thank you for the link.

 

I'm not a fan of those hot temps either. I have a 170 stat and lowered fan temp, plus a lower temp switch(200 on) for the aux fan. My vette runs around at 180 and once in a blue moon, sees 200.

 

100% These cars were designed by the GM engineers to run hotter---however the engineers "design" just may have been influenced just a little bit ---by the EPA.

I use a 180* stat w/fan on/off temps reprogrammed and I'm happy (the Vette sure seems like it's happy too)

 

I like toast!!

Pacer has the right idea, make sure there is a good differentiation between thermo and fan switch. It really wont matter much what thermo you are using 'cause your motor will run at what the cooling system and environment will allow it to run at. That being said, I have always installed a lower thermo in my vehicles just to have it open sooner. I have a 160* one in my '85 to make sure the engine temps dont get too cool that my 4+3 wont engage and yes my car runs cooler than 160* when its cool outside.

 

Oh, dear. A dead horse is about to get a good flogging.

Don, there two basic kinds of people in this world: those who think these Corvettes run too hot, and those that think "they were designed that way." If you think the Hatfields and McCoys could not get along, wait until you experience this.

I am firmly in the "too hot" faction and, curiously, every single C4 Corvette owner -- past and present -- that I meet personally feels the same way. The only place I have met the "designed that way" argument is on these pages.

The EPA argument (reduced emissions) actually applies to all catalytic converter-era cars, so we would reasonably expect them all to have this hot-running characteristic. But we all know from our experience with other cars and trucks that they do not. The C4 Corvette stands out like a sore thumb, and the number of times the heating issue is mentioned on these pages is testament to that. Even my 385-hp, 5.7 liter Tundra engine stays cooler than the 'Vette's, even after towing a travel trailer up a long, steep hill to my house at low speed. The reason: it has an adequate cooling system. Which my '94 Vette does not, 'cause the fans are whirring madly after the same trip, but without the travel trailer (BTW -- new radiator, coolant, and thermostat, block completely flushed, 185 comfortable degrees while on the highway).

Here's my theory, lengthily explained, and you can take it or leave it along with the others:

The 'Vette's radiator is adequately sized for the job -- BUT -- its placement is the problem. Radiators cool the circulating fluid by means of air flowing through the spaces between the cooling fins and carrying away excess heat. Usually radiators are placed directly behind an opening to admit ambient air, and are vertical so they present a perpendicular surface to the incoming air flow -- thus air passes directly through the cooling fins. But look at your Corvette; 1) the air pickup is below the level of the radiator, and the entering air is diverted upward at a steep angle; 2) direct airflow to the radiator is impeded by the condenser unit; and 3) the radiator itself is tilted backwards so that the diverted air from below (that which gets by the condenser) passes OVER the cooling fins instead of THROUGH them.

At highway speeds this is not much of a problem because the considerable turbulence inside the radiator shroud is pushing air all around, including through the fins. But as soon as speed drops the airflow immediately becomes inadequate for the reasons cited above. Notice how quickly the temps come down when the fan(s) come on -- I believe that is because the fans are placed directly behind the radiator and draw air directly through the cooling fins rather than over them.

Anyway, that's my story and I'm sticking to it. Many will howl in protest and cite that tired mantra of the engineers knowing more than me --I won't argue that, but will point out that styling designers and marketing types also had a hand in your Corvette's creation ("Hey guys, let's make the hood low and swoopy to look fast!"). One might also note that Chevy designers were responsible for the late, unlamented Vega, so we know they are not infallible

BTW, I have installed two manual switches to activate either or both fans when I see the temp climbing beyond my comfort zone -- 210 degrees or so. Works like a charm.

Now I await the flames. Casting even the tiniest pebble of criticism at these cars is like calling sombody's wife ugly on this board: "YOU CAN'T SAY THAT, YOU %$&*# SUMB*TCH!"

 

OMG, that is some funny stuff there!!!!

Guys;

I really appreciate the positive feedback on this issue;Obviously this topic is a real HOT Tamale.

No reason to abuse the old glue horse of a topic.

I have heard enough here to decipher a few things; Obviously the ECM is NOT affected by the temp change, and that it has no historical of promoting any adverse issues.........

So, pretty much appears to be a personal preference issue.

..........and personally I prefer a cooler Small Block Chevy........

I really appreciate the time spent helping me on this issue explaining some of the nuances of this specific car type/engine combo.

I'll be back.

Regards,

Don

 

You're welcome, hopefully my experience was the exception.

The couple of times mine did work it did stream live data, but only to the handheld unit. I wanted the info to go straight to the computer & that doesn't appear to be an option.

The only solution their support guys offered was to download and update the internal software, but with no communication to the PC this was impossible.

Let us know how your's works.

 

3D87C4:

I will most certainly do that.

I was having quite a time deciding which unit to get. I had no idea about the live feed option on some of them. I was sold when I was loaned an AutoXray 6000 unit. It worked pretty darn well, and it live fed....just took a few moments to get interfaced with the ECM and OBD1 system.

I want with the 7000 for a few reasons, all the features of the 6000, plus back lit screen larger in size than the 6000 good button layout....and a great price......

Heck at first I thought I just needed a code reader (or a paper clip!) Then I got edjumacated. LOL

In any case, as long as it will help me to find/track issues in this electronic jungle, for me it will be mission accomplished for the same price as some simple readers.....