Hello, just wanted to know how many other guys cars were at 220 or above in traffic... what you did to cure overheating problems. mine is 220 or just above if i'm driving in traffic. have any of you guys wired a toggle switch to the cooling fans. if so, how? i have just the one single cooling fan. thanks for you help and ideas. tom

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86 iroc 305tpi auto. mild cam

 

160 deg. thermostat should cure your prob. it took care of mine

 

Hello, i thought a 160 thermostat would keep the car in open loop. i just put in a 180 thermostat. anybody else run a 160? thanks for all your help, tom

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86 iroc 305tpi auto. mild cam

 

I use a 180* t-stat and a 200* secondary fan switch. Mine will only see 220* on a 95*F day at extended idle, and even then, it won't go above it. Also, make sure you have at least 50% water in your coolant mix. I would avoid a 160* t-stat unless you live in a warm climate year round. Just my $0.02.

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1990 IROC 350
Mods: Too busy trying to make it run right to mod it.
Airfoil, Dynomax cat-back, MSD coil, 180 t-stat, Bald Eagle tires,
Hypertech fan switch, Accel 23# injectors, Holley module, ported plenum,
Ported Daytona Yellow stock base, Moroso valve covers, other stuff,
Streetdampr, Ruger P95DC, hot wife, new oil filter, !cats, !TBC, !AIR.
18.0 @ 85MPH since I'm one big-a$$ MF
"It's better to have and not need than to need and not have."

 

Sorry Mckenzie, I just noticed you have the single fan. Try a switch if you don't mind having to operate it, and also some water wetter with about 30-40% antifreeze in your coolant mix. You may even want to go as far as converting to a dual fan setup, if that's possible, so one of your fans can be easily controlled by a switch that you select in the coolant passage. Also, flushing your coolant system couldn't hurt. Hope this helps.

[This message has been edited by JETHROIROC (edited September 20, 2001).]

 

160* tstat doesnt put your car in open loop mine is fine of course here in FL you get quite a few hot days out. My car will run around town at 180* even with the 160* tstat.

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91 Z-28 Coupe
L-98, 700-r4
Borla cat back
Performance Resource chip
Centerline wheels
K&N, Gutted air boxes
Gutted cats
Best Pass = 13.710 @100
Best 60' = 1.842
on M/T Sportsman Pros

Race Car:
S/P 91 Camaro Z/28
454 LS7 crate motor
Crane Roler cam
Dart intake
1000cfm TRC Carb
Powerglide w/brake
3000# with driver

 

You could also try cleaning off the radiator. Take it out and use a good pressure washer to get the dirt out of the fins.

You might also want to get a new fan motor, maybe your old one is getting tired.

 

i dropped in a 160, and now it doesn't go about 220 much...
next step is to drain/flush the cooling system, refill it with some 40* below, and add a fan toggle switch. should do right nice.

p0

 

If your car gets over 220 I fail to see how a 160 tstat will help over a 180 unless the opening is bigger or your 180 is not working right and is now a 215 tstat.
220 should be the upper limit and that is stop and go driving in Phoenix in July at 3 oclock in the afternoon.

 

putting in a colder t-stat does nothing when the fan doesn't come on in traffic. don't you think the 'stat is open at 220 degrees before the fan kicks on? how can the radiator do it's job when there is no cool air being drawn through it? the stock fan is set to come on at something like 238 degrees. untill that fan kicks on or untill the car gets rolling, the rad can't do it's job effectively, and the engine is gonna get hot. all that is needed is a cooler fan switch or do like i did. locate the pressure switch in your AC line. it is on the passenger side wheelwell. when the AC is turned on the pressure switch turns the fan on. the pressure switch has 2 wires coming out of it, so splice into each of the wires and run each of them into your ****pit and connect them to a switch. when you flip the switch and connect the wires the fan will come on. super easy and free. you could take the 'stat out and if there isn't any airflow throught the radiator it is still gonna get hot guys. so this way you can turn your fan on whenever you want, but if you forget to turn it on, it will still come on at the stock setting 238deg and save your butt. that way when your wife drives it and forgets to turn the fan on it will still come on and not smoke the motor. lets use our heads here.

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86 IROC-Z
305 TPI
700R4 W/ shift kit
3.23 gears
T-Tops
maroon with gold stickers and rims/ black interior
43,000 miles
flowmaster exhaust, edelbrock headers, gutted airbox, converter, and MAF, K&N filters.

soon to come are 3.73 gears and subframe connecters.

[This message has been edited by FlameRedMetallic (edited September 21, 2001).]

 

Hey I have a 160 in mine and headers too, have not yet put a heated O2 sensor in it, and after about 5 or so minutes after startup it goes into closed. Oh ya I also have the fan switch hooked up, Ill tell you thats the cure all too.

 

Flame is correct, it has everything to do with the temperature setting that the fans come on. I have tried every temp of T-stat there is, and until I adjusted my Fan temperature in my eprom, they all resulted in the same thing.

The eprom does not turn on the fan until around 230* and then turns off at around 220*. If you want your car to run cooler in traffic, either install the fan switch in the passenger head that comes on sooner, or adjust the eprom.

PS: Running a 160* t-stat causes a lot of other problems. The ecm was not designed around a 160* T-stat and there is a lot more that needs to be changed than just the fan temp enable setting to make it work properly. And those "off-the-shelf" eproms don't do them right either. You loose certain aspects of your "Block Learn" as it too is enabled based on CTS. All a 160* t-stat does, is waste gas and makes your run overly rich @ WOT as the engine thinks it is still in "start up" mode.

 

Im running a 180 degree thermostat right now, had 195 in until yesterday. I installed a switch in my fuse panel cover to turn the fans on when I want, so I can keep the temp where I want it. Ten minute job. My car was running at about 220-230 before, but I keep it less than 200 now.

 

well how i fixed my problem i put in a fan switch put in a 160* live in florida gets hot and took out my ac radiator because my ac was decompressed anyways from the engine swap and was lot cooler after that, next step cowel induction

 

i had a 160 stat all summer and the car ran nice and cool but i noticed gas mileage suffered. i put a 180 last week to prepare for the cooler weather and noticed my gas mileage is better but the car runs a little hotter.

 

mine only climbs over 220 when the A\C is on.

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- David
88' GTA 5.7L TPI MODS---> air foil, K&N, Shift Kit, 180* therm, TB bypass, Gutted CAT, Flowmaster 80 Series

 

i had the same problem except for it was all the time. All I did to fix it was flush the radiator. has not been over 170 since

 

you can get a controller that also kicks on the fans at a lower temp, I got mine at Checker, and set it to turn on fairly early Im not exactly sure the temp, it has its own sensor and relay, you just have to mount it somewhere, I think I payed 20-30 for it and you can adjust it to different settings, it took a while to get what I wanted but now that its set no probs. Just need to find a better place to mount it so it dosent stick out so bad.

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'87 Monte Carlo SS,with '89 IROC 350,700 trans, blew up 3.73 posi stuck with crappy 2.73's neeed gears! hooker headers, flowmaster 2 1/2" exhaust true dualls, recently installed a set of alum vette heads 58cc, new cam for a paxton, recently installed paxton, OMG need a posi bad. Found a guy who can build me a ford 9" (yep sorry guys) for less than 500 then comes all the goodies such as disk brakes so on and so on, will it ever end?? I hope not!!

 

IMO the single most important mod you can do (if everything else is working like it should) is a high flow waterpump.

I went with a Stewart Stage I and it flat works. On my ZZ4 with a new OE radiator and OE dual fan setup it would quickly push 240 in traffic. I installed a 160 Tstat, and the car still wanted to run hot. It just took a little longer to do it. I next installed a Hypertech fan switch. It helped some but not enough. I next installed the Stewart pump. Voila` it works like a charm. On the worst days this summer it rarely saw 200 in heavy stop and go traffic.

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Mike

'90 IROC-Z , 5-speed, ZZ4, G1 Trick Flows
Moderator SEThirdgen

 

wut about a high flow therm.? like a generation 2 at auto zone?

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- David
88' GTA 5.7L TPI MODS---> air foil, K&N, Shift Kit, 180* therm, TB bypass, Gutted CAT, Flowmaster 80 Series

 

Mac,

My '86 TPI runs at about 205°F, in traffic, AC on, 95°, 95% RH, stop and go. I use a 180°F thermostat. The more important thing is to have a coolant controlled fan switch at something below 223°F. As Glenn indicated, the most effective way would be to rewrite the EPROM to about 190°F instead of 223°F. I took the less pristine method of installing a parallel switch to control the fan while still allowing the ECM to do it's job. If I ever have to do an emissions run, I unplug the auxilliary sensor and run like the factory made it - hot.



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Later,
Vader
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Justice and Freedom will Prevail

 

Jeff, I don't if I would say reprogramming the eprom is the MOST effective, as a fan switch is equally effective.

What I would say, is that you don't get dirty or use any wrenches. Do need a 7mm socket/scredriver to unscrew the two screws holding the "cover plate" on the ECM. But its only a 5 minute job, including programming time.

Let go and come over to the "dark side". Experience the power you have always dreamed of but denied.

 

Im runnin a 160...runs 160 all day....less I get on the gas fer a bit (e-way)

then it creeps to 180..

never getsover what the stock therm would read...

I also have dual cooling fans..run constantly

 

I run 165 - 170 with a 160 stat unless i sit around in traffic to long...

that is becuase my secondaries arent coming on anymore... this reminds me, i need topost about that!

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1989 Chevrolet Camaro IROC-Z
L98 - 350c.i. TPI, rebuilt 700R4 auto w/shift kit, Dual catalyst Monza PaceSetter Cat-Back, SLP 1 5/8 Coated Headers, 3.23 Posi rear, Hypertech chip with 160stat, MSD 6A, Under-Drive pulleys, AFPR, K&N's, !Air Box w/ Ram Air, moddified MAF, !TB Coolant, Spohn Dual Cat SubFrame Connectors, Alarm, Keyless entry, remote starter, 92 Z28 AeroWing, Brand New Paint (6/21/01)

Future: ZZ4 TPI w/EGR, T56, 3.42 or 3.73, Spohn strut tower brace and LCA's

1989 Chevrolet Celebrity Eurosport
2.8 MPFI, no mods
225,000 miles and still ticking!

More info and pics on my webpage:http://go.to/iroc-z

AOL IMer: GPA 0point0

 

everything on mine is stock and i've never seen it climb over around 175-180.....no complaints though

 

I used to run it at 180 but since I removed the smog pump it runs at 220-240

 

when i bought the veh., the car wasn't running. i rebuilt the trans and motor...took off all the smog stuff, so i don't know if it ran cooler with the smog stuff on. i only have appx 100 miles on fresh rebuilt motor... will a new motor have a little more heat until it wear in and loosens up? seems to go a little above 220 and then drops (cooling fan comes on) i would like to think everybody for their help and ideas...i like my iroc...bought it as a project car...boy do i have a long way to go. thanks again, tom

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86 iroc 305tpi auto. mild cam

 

I think that every body has to keep in mind our engines are not ment to run at that cool to be using 160* thermos. Our engine maximum performance is at about 180*. Don't ask me how to explain why I just got thru this same ordeal and my father who is a GM certified mech for 32 years told me this and has taught me everything I know until this day. JMO