grind4it

So, I have FINALLY finished my modified LS1 swap into my once dead 1985 Corvette. Today is a good day.

Only one issue and I hope that someone here can help me solve it.

I am running at 200*F – 225*F

Here is what I have done so far:

Replaced the thermostat

Replaced the radiator cap

I tried to get the block to burp by filling through the coolant temperature sensor, rocking the car and slightly reving the engine with the cap off.

Is it possible that the block still has not burped?

I am running the factory 1985 fans. They are both coming on at 180*F
Is it possible that these fans are undersized? I have been following this build http://mcspeed.homestead.com/LSXC4.html the only difference is that I used a larger cam, CNC ported 243 heads and that’s about it. In this build they used the factory fans.

Any help would be great, thanks Mark

mrx8200

iTrader: (1)

My car sits right in that range stock. I don't think there's anything wrong with temps in that range.

01ssreda4

iTrader: (96)

These cars/engines run 230 stock.

grind4it

I don't want to sound like a total idiot, but am I understanding correctly that the 2001 LS1 I put in my corvette has an operating temp 230*F?

At what temperature should I become concerned? My after market gauge only goes to 250*F Also, I have a 185*F thermostat shouldn't run cooler?

Again, I am not trying to sound like an moron, I just don't want to screw up my engine.

Thanks, Mark

HotSilverBird

lol hell no! ....you have a problem someplace. You should be around 190-200. I have a 99 ta and a 02 formlula and have never seen over 205 even in the middle of summer.

grind4it

Thanks, any idea what might be wrong?

zamora7

iTrader: (4)

My car runs consistently at the 210* mark on my factory gauge, but from what I've heard/read they run slightly higher than that. I think the fans when stock come on at the 220* range.

Quick Sh0t xMLx

Seems pretty normal to me. Around town in my C5 in the hot weather the car is always between 215-230, it cools down on the highway.

grind4it

Okay, I feel a little better. Can anyone tell me at what point I need to worry? The after market gauge only goes to 250*F and I am using a factory thermostat.

HotSilverBird

Lets get serious here......when is it at 225? Why would it be any different than the old engine?

Both my ls1 cars run at 205 just like my OLDER 89 GTA did.

NHRAFORMULA00

iTrader: (2)

230 degrees is hot! should not be that high. Have you tried to bleed the air that could be traped in the heads out? There is a small hose under the throttle body(it connects both heads together),let the car run for a while and pull the hose off while its running for at least 10 seconds to see if bubbles come out.Some times air gets traped in the heads and creates HOT SPOTS.Do this three or four times in like 10 minutes and all the air should bleed out.When the car has cooled simply make sure radiator is topped off.

01ssreda4

iTrader: (96)

seriously, you will never get an accurate temp reading from a factory gauge. I run an aftermarket gauge and I have seen as high as mid-230s in the summer with the ac on and idling. Car ran perfect at that temp, no issues. And stock fan low setting is in the low/mid 220s. These motors dont run 190 unless you have a 160 thermostat and have your fans set to come on early or its cold as ****.

grind4it

I'm not running factory gauges. This is a Auto meter gauge. When I parked the car it was up to 230. When I was driving I was at 210. It was 77 outside and I do not have AC. What do you think?

01ssreda4

iTrader: (96)

Sounds pretty normal, As long as it doesnt get too much over the mid 230s you are fine IMO. I got on mine at about 236 to see if there was any missing or pinging and it was perfect.

needtransam

iTrader: (2)

I have a similar issue but mine "sometimes" gets hot but when its parked after a drive, since i turn on the engine the fans kick in and cool it down rapidly until the Temp gauge goes back to the middle

LilJayV10

iTrader: (39)

Are you running electric fans? If so where is the temp sensor at? After I did my head/cam swap it took forever to get all the air out.

After you run it is the coolant level going down at all?

I am going off the factory gauge so who knows what temp I am actually at.

soundengineer

iTrader: (16)

230 is very normal if you havent changed any fan settings...
just because you have a colder thermostat doesnt mean its going to run less hot.. just means its going to get the slower because it opens sooner.

also.. being an 85 corvette.. if you still have the stock radiator.. you need to buy a new one and upgrade to a new radiator designed for an ls1
that will help greatly

if you are running the ls1 pcm, then change the fan settings to come on lower to keep you on the 210~220 ish range

ls1's make the most power at in that range

1quickirocz

LS1
The PCM commands low speed fans on under the following conditions:

• Engine coolant temperature exceeds approximately 108°C (226°F).

• When A/C is requested and the ambient temperature is greater than 10°C (50°F).

• A/C refrigerant pressure exceeds 1482 kPa (215 psi).

• After the vehicle is shut off if the engine coolant temperature at key-off is greater than 113°C (235°F) and system voltage is more than 12 volts. The fans will stay on for approximately 150 seconds.

The PCM commands High Speed Fans on under the following conditions:

• Engine coolant temperature reaches 112°C (234°F).

• A/C refrigerant pressure exceeds 1710 kPa (248 psi).

• When certain DTCs set.



this is right from GM Service Info for a 2001 camaro with a LS1. I think your ok. have no worries. As long as it cools down when the fans cut on then your good.

sjsingle1

iTrader: (1)

radiator clogged? or full or leaves n crap in the front?.......mine was

eamador11

You are correct, stock LSx motors run 225-230 deg. Put a 160 stat and retune fans accordingly and youll be at 180deg cruising; 220 max in 90+deg weather in traffic. 275-300 deg is where you should worry