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Keep it cool - Boss 302

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I am in the process of improving the cooling capability in my Boss 302.
Here is what I have now:
Stock Boss 302 motor with a AED tune with 102 octane race gas.
Open upper grill with screens as pictured.
Oil cooler 972 Setrab in lower grill area.
Ford Performance all aluminum radiator.
All the hood vents I can fit in this hood.
Here is what I am planning:
Fluidyne all aluminum 3 row radiator.
Motorcraft yellow coolant. 50/50 mix.
Run this air deflector as pictured to allow more air through the lower grill.
Fabricate some side plates within the grill area to funnel more air.
Questions:
Will adding Water Wetter (1,2 or 3 bottles?) improve this cooling?
Will the changes work better than what I have currently?

Boss 27.jpg

IMG_8321.jpg
 

carver

breaker of wrenches
445
598
ontario
Great looking Boss !
It looks like you have pretty much got it covered. My Boss is stock and I have no overheating so far, but I'm in Canada and don't see the high temps like South Cali and Arizona !! Those guys might have some other additional recommendations. ( tranny cooler and rear end cooler )
Guess it depends on the level of competition your involved in. :hellyeah:
 
I am making one change to the list above as far as parts go. I decided to go with the Kenny Brown triple pass radiator. I need to keep things as cool as possible until I figure out to get my AEM CD7 working properly so I can monitor temps of the oil and the coolant. It has been hot in Minnesota for the past few weeks. I think the rear end cooler may be next in line for cooling add-ons. The transmission is being cooled by a Shelby transmission cooler scoop for now. The car primarily sees track days which consist of six 25 minute sessions in a day.
 
Open upper and lower grills help temps quite a bit. Most people run the 302S style grills or like a Roush bar style. The lower grill especially has a very small opening compared to the 302S one which is fully open. I didn't see in the post but if you have the S grills ur pretty much covered
 
The cooling temp / oil temp challenge is a battle most of us stubborn, will not remove the air conditioner group fights. I have a 2012 with the Boss 302 lower fascia so a bit different mix, but this is my view and there are additional thread out there on the site with more information.
- Biggest improvement is the front grill opening it up. Went from the fog lights to rough style bar knock-off, ultimately cutting the bars and adding honeycomb mesh from https://www.customcargrills.com/Custom-Grill-Mesh.asp. Each iteration made a difference
- water wetter helped a few degrees with the 50/50 coolant mix; followed the bottle instructions based on the cooling capacity
- hood vents made an improvement
- if you can box it to the radiator (i.e. no condenser) everyone on the site lists that as the biggest delta and Calipaldi Racing also confirmed
- the marginal improvements, no step change were the 302s radiator, high speed fan, high flow water pump. They all helped when the car was not under load so cool down was quicker or low push laps.
Good luck, this is really trying to find the balance between oil and coolant temps within the shared air box
 
100
109
Utah
Open upper and lower grills help temps quite a bit. Most people run the 302S style grills or like a Roush bar style. The lower grill especially has a very small opening compared to the 302S one which is fully open. I didn't see in the post but if you have the S grills ur pretty much covered
BKBoss302: I was wondering if you have or will upgrade your water pump or maybe go with an electric water pump to increase flow and pressure due the big increase in water pump pressure needed when using a 3 pass radiator?
 

ArizonaBOSS

Because racecar.
Moderator
8,730
2,734
Arizona, USA
Despite the smaller surface area, the lower grille opening is more crucial to vehicle cooling than the upper grille is. The air velocity is much higher down there. That ramp is an interesting idea and may help. Boxing in the radiator/oil cooler is a must. Get the oil cooler as close to the radiator as possible to eliminate air stagnation--however this will drive up the engine coolant temps.

Coolant...on the race cars we aren't allowed to run any--so we run straight water plus one bottle of Water Wetter. I don't believe that additional WW will help at all, based on the product information on the bottle.
The Ford Racing radiator looks nice but didn't do any better than the factory B302 radiator under race conditions. I switched to a C&R radiator and that had a major positive difference in CHTs. The Fluidyne may be equivalent, not sure. The Fluidyne cost is certainly better.
Even with all this, both @captdistraction and I have heat control issues at high altitudes (4500ft) in the heat (95F) for extended runs. Much of this is RPM-related, as well. If you can get away with driving a gear higher in spots where you don't have to wring the car's neck, it will help quite a bit.
 

Ludachris

Chris
Staff member
Moderator
1,658
1,962
Exp. Type
HPDE
Exp. Level
5-10 Years
Newcastle, CA
I am in the process of improving the cooling capability in my Boss 302.
Here is what I have now:
Stock Boss 302 motor with a AED tune with 102 octane race gas.
Open upper grill with screens as pictured.
Oil cooler 972 Setrab in lower grill area.
Ford Performance all aluminum radiator.
All the hood vents I can fit in this hood.
Here is what I am planning:
Fluidyne all aluminum 3 row radiator.
Motorcraft yellow coolant. 50/50 mix.
Run this air deflector as pictured to allow more air through the lower grill.
Fabricate some side plates within the grill area to funnel more air.
Questions:
Will adding Water Wetter (1,2 or 3 bottles?) improve this cooling?
Will the changes work better than what I have currently?

View attachment 66077

View attachment 66078
This thing looks great. Well done.

Please do create a profile for the car with some more photos. I can connect this thread to it to act as your build thread.
 

Dave_W

Cones - not just for ice cream
979
1,271
Exp. Type
Autocross
Exp. Level
20+ Years
Connecticut
Even with all this, both @captdistraction and I have heat control issues at high altitudes (4500ft) in the heat (95F) for extended runs.
Reminds me that I had the temp light come on during my Boss Track Attack. It was early July in a heat wave, temp was 100F or a little over. Being from New England, where we get 95F with oppresive 95% humidity, I really didn't mind the "dry heat" of Utah at all, as long as I kept hydrated.
 

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