91 camaro racer

iTrader: (2)

today i was driving my 91 camaro on the highway to do some carb tuning. my temp gauge got to the 0 in "220" so i am guessing around 230 or so.

my engine is a pre-86 350 with aluminum heads, headers, cam(.458 lift), non-computer controlled anything. stock radiator with stock style dual fans wired to a manual switch(came stock with single fan), 160* thermostat, and just recently flushed.

i was driving around town and the temp got up to 220 or so with the fans on. that is usually as high as it gets. then when i went on the highway driving at 75 mph it got to 230. the fans were on constantly through out the drive. i do have an air dam installed but it has seen better days.

any ideas on what i could do to get it to drive cooler? i dont like it being that high.

Ozz1967

iTrader: (4)

If it's anything like my 84, the temp gauge is off. I have a 180 themostat and a 215 fan switch (single electric fan), but the gauge reads 240+ when the fan kicks on so my guage is about 25* hot. Unless your coolant is boiling over, I wouldn't worry about it if it steadies out at the 23o*mark. You can hit it with an IR thermostat/gauge to see what the temps are running in the radiator.


If the temps keep going up, i'd flush the system and replace the hoses and make sure your air dam is in good shape.

91 camaro racer

iTrader: (2)

yeah i will have to find my infared temp gauge and check it. i havent noticed any coolant boil over. the resivour is still at the same level i set it at.

i will double check my air dam. if it is bad i will find a new one.

Ozz1967

iTrader: (4)

If it cools fine around town but heats up at highway speeds, then that's a good indicator of a bad air dam or even possibly a flow problem, hoses, water pump going bad etc.

91 camaro racer

iTrader: (2)

It stayed a little warm around town too

dr3wberryTM

230 in summer isn't too bad. And if your gauge is off (good possibility) then you don't really have much to worry about

91 camaro racer

iTrader: (2)

yeah i am going to run it here in a little bit to check some things and i will check the temp with my infrared gun. should i check it where the sensor is between 1 and 3 plugs or at the thermostat housing?

dr3wberryTM

I would imagine the housing. But I suppose you could check both. Lol

mantaguy

iTrader: (5)

Check it at the thermostat housing.

91 camaro racer

iTrader: (2)

ok thank you

91 camaro racer

iTrader: (2)

Checked the temp with my gun. When the gauge reads 220, the thermostat housing reads 175-180. So yeah I think my gauge is off just a little...

Now is it usually the gauge or the sender in the head that is incorrect?

Ozz1967

iTrader: (4)

90% the gauge. Remember, by now the "newest" Thirdgen is 22 years old.

91 camaro racer

iTrader: (2)

thats true

mantaguy

iTrader: (5)

I would change the sending unit 1st,that also has 22 yrs of crust and rust on it,so it wouldn't hurt to change that.

Bob88GTA

iTrader: (2)

Racer, Just some info on how the air dam functions.

These cars cannot cool themselves at highway speeds without an air dam in place. You fans do absolutely nothing above 35 mph except get in the way of air flow.

Note the air dam does not force airflow up in front of the radiator, it's purpose is to create a vacuum behind the radiator, so that air is sucked in from the front (air moves from a hi pressure area to a lo pressure area).

I H8 WWD

iTrader: (5)

My 2cents. Make sure your fans are pulling air, not pushing. Buy a new air dam, they're cheap.

Never heard it explained further, thanks.

91 camaro racer

iTrader: (2)

That makes a lot of sense thank you. So would it make any difference if someone curved The lower edge forward to make it a little scoop? Or is it better as a straight down piece?

91 camaro racer

iTrader: (2)

Both fans are working correctly. My air dam was loose and I could bend it back easily. Replaced some missing bolts and fixed a crack. It should be good now.

91 camaro racer

iTrader: (2)

the old sending unit did look pretty bad. swapped it out for a new one and the gauge is still off the same amount. 220 on the gauge is 175 at the thermostat

mantaguy

iTrader: (5)

This is the diagnosis for temp.gauges for the Firebirds.I assume their the same for the Camaro's

Well now you know it's your gauge.

91 camaro racer

iTrader: (2)

yeah i will just end up getting a new temp gauge. figured i would at least try the sender first.

what book is that?

mantaguy

iTrader: (5)

Service Manual for my 86 TA.

91 camaro racer

iTrader: (2)

never updated this.... ended up getting a water temp gauge and sender from glowshift. installed the gauge and now it reads perfect. the stock gauge was bad.