All 400+ci guys step inside........

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Jun 20, 2007 | 05:20 AM

gtodoug

Thread Starter

Burning Brakes

Joined: Feb 2006

Posts: 903

Likes: 5

From: Miami FL

All 400+ci guys step inside........

Is it normal to have increased coolant temps with a 403ci motor? I recently got my motor installed and I'm doing some break in miles and the motor is consistantly running between 193-202 with very very light driving, and 201-212 sitting at idle.

I am currently running a stock radiator and 160* T-stat.

The motor setup is a 403,afr 225's, 11.5:1 CR.

Please advise. I'm not sure if I should be looking to purchase a radiator or not.

Dougie

Jun 20, 2007 | 01:19 PM

Dvlray6

Drifting

Joined: Dec 2005

Posts: 1,777

Likes: 1

From: Port Neches Texas

St. Jude Donor '07-'08-'09

Quote:

Originally Posted by gtodoug

Mine doesn't do this. I have a 427 MTI built engine. It runs 170-180 most all of the time. 190 under idle in Texas heat in stand still traffic with the AC on. I have the stock radiator, underdrive pulley, stock water pump, and 160 stat.

Jun 20, 2007 | 10:10 PM

UDRIVESLOW

Racer

Joined: Aug 2005

Posts: 425

Likes: 0

From: odessa TX

did they reprogram for the lower coolant temp???
your thermostat does not control your engine temp...............
your fan does.................................... .............................

udriveslow

Jun 20, 2007 | 10:49 PM

gtodoug

Thread Starter

Burning Brakes

Joined: Feb 2006

Posts: 903

Likes: 5

From: Miami FL

I understand that the fan controls the temp and not the t-stat. The problem with controling the fan is that you have no control over it until coolant temps reach 192*. I'm thinking there is air in the system at this point.

Jun 20, 2007 | 11:56 PM

Mike Francoeur

Racer

Joined: Nov 2006

Posts: 354

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From: New Lenox IL

A new motor that's a little "tight" with higher than stock compression will run a little hotter.

Jun 21, 2007 | 10:46 PM

Joe_G

Tech Contributor

Joined: Jul 2002

Posts: 14,950

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From: St. Louis, MO

St. Jude Donor '08

ttt for ya.

JP had pretty constant cooling problems with his cammed LS7 in his C5. It used to run about 230 in traffic with AC on, 200 on the highway. Norris and Roger put in two different types of fans to no avail. It never actually overheated, just ran hotter than we all like, but it wasn't a problem in the end and it ran consistent mid-high 10's in the quarter.

Jul 1, 2007 | 03:26 PM

Joe_G

Tech Contributor

Joined: Jul 2002

Posts: 14,950

Likes: 264

From: St. Louis, MO

St. Jude Donor '08

Hey Doug,

Did burping the air out of the system work?

Jul 1, 2007 | 04:04 PM

Wayne O

CF Senior Member

Joined: Feb 2006

Posts: 23,313

Likes: 25

From: Tucson Arizona

That doesn't seem tremendously out-of-line based on my experience. I checked my coolant yesterday sitting at a light with the a/c cranked and it read 205...it was 108 outside and God only knows how hot on the asphalt. The coolant temp dropped down after I started moving again. I've driven my LPE 403 in the summer heat of Arizona with the stock radiator without any problems