90 getting hot after rebuild
Thread Starter
Melting Slicks
Joined: Jan 2004
Posts: 2,992
Likes: 0
From: Henryville IN
90 getting hot after rebuild
I rebuilt the 90 this winter it is bored 30 over ,zz9 cam ,195 heads ,TPI big mouth ,over size SLP runners ,polished and ported ,headers ,58 TB. Ok the problem now. This is getting hot pretty quick even with both fans running and I did put in a 160 thermostat when I say hot I mean between 240-248. Some one said I need a bigger radiator now. This is a auto and I still have the air. Any suggestions? If I do need a bigger radiator where do I go for it and what do I ask for? 
Thread Starter
Melting Slicks
Joined: Jan 2004
Posts: 2,992
Likes: 0
From: Henryville IN
It doesnt seem to get hot real fast it takes a while. But do they have a better water pump then stock to help out also? Does Griffins build a bigger radiato that will fit a C4?
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Originally Posted by 1hot90
It doesnt seem to get hot real fast it takes a while. But do they have a better water pump then stock to help out also? Does Griffins build a bigger radiato that will fit a C4?
As to the water pump, check Summit, they sell an impeller disk that pop rivets onto the back of your pump's impeller (this is for the "star" impellers not all are) I just made my own disk from some stainless steel and riveted it on. The disk prevents cavitation of the pump (water going behind the impeller instead of being moved through the pump) and moves more water.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
First, the 160* thermostat won't help, or make it run cooler. Once the stat is open, whether it is a 160* or a 195*, the water is free to get hotter. How many miles have you put on this? New engines tend to run hot. It may pay to get some run time on it, being careful not to let it over heat badly, before you start investing in cooling system upgrades. Was the radiator out and checked by a pro while the engine was out? The area between the condenser and the radiator has been cleaned? Retarded timing can contribute to running hot. IF a higher capacity radiator is needed (unlikely), our own sponsor, De Witts makes a great, two row, all aluminum, replacement radiator. It's a bolt in and has approx double the cooling capacity of the stocker, which is at least adequate in most cases.
RACE ON!!!
RACE ON!!!
Le Mans Master
Joined: May 2000
Posts: 7,033
Likes: 12
Did you check that you don't have a bad head gasket? If this thing didn't overheat b4 you did your mods I don't think it should overheat now. 248 is getting very hot. With your mods if your stock system is in good shape it should be able to cool your setup.
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Le Mans Master
Joined: Oct 1999
Posts: 6,366
Likes: 34
I have a 90 with a 355, ZZ9 cam, afr heads as well. with a stock chip it gets to 240 no problem and real fast sitting still. I thought it was going to blow up on the smog dyno. I remember panicing when driving on the streets because it got so hot.
With a custom made chip, I am cruising at 180ish on the highway probably 200-210 in traffic. what temp are your fans comming on?
I later pulled the radiator, cleaned it out with a hose, inside and out. then shot compressed air through the fins. this helped out a lot I noticed. there was a ton of sand in the fins.
With a custom made chip, I am cruising at 180ish on the highway probably 200-210 in traffic. what temp are your fans comming on?
I later pulled the radiator, cleaned it out with a hose, inside and out. then shot compressed air through the fins. this helped out a lot I noticed. there was a ton of sand in the fins.
Burning Brakes
Joined: Feb 2003
Posts: 1,218
Likes: 0
From: Rolla Mo
Alan try turning on the heater for about 15-20 minutes. I had both of my radiator hoses off, did the refill procedure, and she was getting VERY hot. I was driving across town the other day and ended up running the heater in 95+ temps outside to help drop the temps. After about 15 minutes or so, she dropped right down to 185-200 range, and not a problem since. I dunno why, but it did work.
Doug
Doug
