On the 'mildly' Cheap SS Monte Carlo chasing a 9.0____(oil pan woes)

GroceryGetter83

LS Mafia
Supporting Member
Sep 18, 2018
676
2,406
93
Tampa, Florida
No. The low pressure was created right where I have my intercooler. I believe it's some of the reason I'm having issues.

My past experience with my son's 80 Cutlass was it had all kinds of overheating issues until we reinstalled the factory chin spoiler/damn (wrong term I'm sure) under the radiator. Once we installed that it never had an overheating issue again at highway speeds or under heavy load. And that motor made alot of heat in a hurry without any issues for the cooling system.
I’ve got the factory front air dam on mine and it’s never overheated. And I’m talking about sitting in traffic in Florida in August. Temps never went over 205*F.

0A9D031F-B8C7-4932-938B-F0427CC48FDF.jpeg
 
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motorheadmike

Geezer
Nov 18, 2009
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Saskatchewan, Truckistan
Look at post #6



I don't have a coolant overtemperature issue, only an IAT issue. Without meth it will see 230 degrees. With meth 190. Yes, my shroud is tight and the radiator works. The issue is the lack of low pressure under the rad as you described. I'm guessing here, but the stock rad worked fine with the high HP 305 lol(180 hp). It's designed to create a low pressure behind the radiator, but my issue is I have the cac very close to the factory air 'dam' or whatever it's called and it's impeding air flow through that contraption that GM thought was a good idea - resulting in a 24" x 8" air opening for the radiator..

I plan to cut out more of the factory steel piece and then put a chin spoiler below the radiator. I am going to pull the the black lower piece off from the enduro bumper. I believe you are spot on with your description - I have have no low pressure area behind the radiator and cac. Also, keep in mind that I don't overheat this thing with a single row factory radiator (until I lifted the head) making 800 or so HP at speed. On the street it works fabulously - below 210 all the time unless I get into hill climbing at 30-40mph. City driving, highway driving it never sees 205.

Regarding bleeding the air out of an LS - yes it's a chore UNTIL you drill 2 or 3 1/8" holes in the t-stat. Before I drilled the holes it would take 5-7 heat cycles to get full of coolant. It probably will be a problem if I drive it in weather below 30 degrees, but I don't think drag radials and snow work well together so I'll leave it home when it's like that out ;).

I am going to do your oil pump mod while the radiator is out because it's pretty easy presently to get the balancer and front cover off. How much oil pressure does it yield? I really don't wan tot empty the oil pan in the name of an extra 10psi of pressure.

Yeah, those holes aren't helping. The MCSS airbox is designed to use air velocity from a high pressure area at the grill moving across the HXs and to the low pressure area behind the HXs. If I was going to make a suggestion it would be to seal up the stock ducting, divorce the intercooler from that area and lay it flat, put a scoop under the car to feed it (you can even make it adjustable for track vs street), and duct it to the low pressure area behind the core support. Isolate it from the heat source and give it a dedicated air stream. Its what I did with my TBSS. That will help both your IATs and any future demands on your cooling system from things like towing.

Edit: Oil pressure isn't oil volume. Pressure doesn't bleed the pan, volume does. You should see upwards of 70psi with the shims and porting.
 
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1320John$$$

G-Body Guru
Sep 18, 2019
951
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Pennsylvania
Yeah, those holes aren't helping. The MCSS airbox is designed to use air velocity from a high pressure area at the grill moving across the HXs and to the low pressure area behind the HXs. If I was going to make a suggestion it would be to seal up the stock ducting, divorce the intercooler from that area and lay it flat, put a scoop under the car to feed it (you can even make it adjustable for track vs street), and duct it to the low pressure area behind the core support. Isolate it from the heat source and give it a dedicated air stream. Its what I did with my TBSS. That will help both your IATs and any future demands on your cooling system from things like towing.

Edit: Oil pressure isn't oil volume. Pressure doesn't bleed the pan, volume does. You should see upwards of 70psi with the shims and porting.
Mike what pound rad cap are you running
 

motorheadmike

Geezer
Nov 18, 2009
8,976
27,522
113
Saskatchewan, Truckistan

motorheadmike

Geezer
Nov 18, 2009
8,976
27,522
113
Saskatchewan, Truckistan
Sorry the question was actually supposed to be directed to 64 nail head

LOL - all good. The Monte acutally has two rad caps. One on the rad tucked into the core support and one in the upper rad hose.
 
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Northernregal

Sloppy McRodbender
Oct 24, 2017
3,359
12,828
113
Red Deer, Northern Montana territory
Look at post #6



I don't have a coolant overtemperature issue, only an IAT issue. Without meth it will see 230 degrees. With meth 190. Yes, my shroud is tight and the radiator works. The issue is the lack of low pressure under the rad as you described. I'm guessing here, but the stock rad worked fine with the high HP 305 lol(180 hp). It's designed to create a low pressure behind the radiator, but my issue is I have the cac very close to the factory air 'dam' or whatever it's called and it's impeding air flow through that contraption that GM thought was a good idea - resulting in a 24" x 8" air opening for the radiator..

I plan to cut out more of the factory steel piece and then put a chin spoiler below the radiator. I am going to pull the the black lower piece off from the enduro bumper. I believe you are spot on with your description - I have have no low pressure area behind the radiator and cac. Also, keep in mind that I don't overheat this thing with a single row factory radiator (until I lifted the head) making 800 or so HP at speed. On the street it works fabulously - below 210 all the time unless I get into hill climbing at 30-40mph. City driving, highway driving it never sees 205.

Regarding bleeding the air out of an LS - yes it's a chore UNTIL you drill 2 or 3 1/8" holes in the t-stat. Before I drilled the holes it would take 5-7 heat cycles to get full of coolant. It probably will be a problem if I drive it in weather below 30 degrees, but I don't think drag radials and snow work well together so I'll leave it home when it's like that out ;).

I am going to do your oil pump mod while the radiator is out because it's pretty easy presently to get the balancer and front cover off. How much oil pressure does it yield? I really don't wan tot empty the oil pan in the name of an extra 10psi of pressure.
Fill your rad through the top hose on the water pump, much easier and less of a fight.

Do you have an IC pic with the front off?

Maybe this high tech solution will work?
MCR_0054.jpg


Bonus points for doing this and it working.
Screenshot (36).png


Yeah, those holes aren't helping. The MCSS airbox is designed to use air velocity from a high pressure area at the grill moving across the HXs and to the low pressure area behind the HXs. If I was going to make a suggestion it would be to seal up the stock ducting, divorce the intercooler from that area and lay it flat, put a scoop under the car to feed it (you can even make it adjustable for track vs street), and duct it to the low pressure area behind the core support. Isolate it from the heat source and give it a dedicated air stream. Its what I did with my TBSS. That will help both your IATs and any future demands on your cooling system from things like towing.

Edit: Oil pressure isn't oil volume. Pressure doesn't bleed the pan, volume does. You should see upwards of 70psi with the shims and porting.
I see 80psi @ 6000rpm and 40psi @ idle with the shims, I believe a single #8 nut was 0.125" of shim?
 
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motorheadmike

Geezer
Nov 18, 2009
8,976
27,522
113
Saskatchewan, Truckistan

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