Solving V8 Conversion overheating, Exhausting out the HOOD is THE answer |
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Solving V8 Conversion overheating, Exhausting out the HOOD is THE answer |
stewteral |
Apr 24 2010, 11:00 AM
Post
#1
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Old Member Group: Members Posts: 384 Joined: 4-December 07 From: Camarillo, CA Member No.: 8,424 Region Association: Southern California |
Hey V8 conversion 914ers,
I’ve been running my car for some 7 years now and chose to exhaust the radiator out the bottom of the car. It seemed to work fine, but in the 100 degree summer heat of Willow Springs, I was seeing water hitting 250 degrees with fans blazing. We all know that from the 60’s, race cars have vented out to TOP of the hood and it worked well for a friend’s Corvair 327 Chevy we ran at Riverside (142 MPH on the short course back straight). However, I originally didn’t want the car to look too “radical.” When I got the car running it had 11” fender flairs, side scoops, roof scoop and a wing……Ya’ cops won’t notice my car! With some time before my next event, I redid the whole radiator layout where I sealed the bottom of the trunk, HACKED a hole in the hood and fabricated radiator shrouding and an exhaust air dam. I upgraded my fans too. This morning in 60 degree temps, I took the car for a drive AROUND town at low speeds to see if I could keep it from overheating in traffic, as it used to. What I found surprised me: I drove the whole run with NO fans and water temp at 140 degrees. When I was caught by a stop light, the temp went up to 160, but once moving again, it moved back down. I jumped on the freeway and both oil and water dove down to 120 again. EUREKA, I have found my solution! Conclusion: -Of course 120 is lower than desired, in spite of the 180 degree T-stat, but I’m aiming at the right temp ON-Track in Summer. If I want to so some street driving, I can always tape off some of my intake opening. -In the previous configuration, I would have had to run the radiator + oil cooler fans and worry about over heating, now with NO fans, the temps are on the low side. -Before, the oil temp would exceed the water temp by some 30 degrees, now the oil matched the water temps, at least in street driving. -The internal hood bracing defines the hole shape as a trapezoid, so I cut all the width I could get right to left. The back edge is defined by the rear wall of the trunk and from there I measured 12” forward, held my breath, and cut. -If your V8 car is on the edge of overheating and big fans aren’t enough, give this a try. Mine is a pure “racer” design, but our friend byndbad914 came up with an attractive louvered approach that keeps his 500 HP small-block cool. In another design, AndyS created a very attractive molded “air dam” for his LS1 conversion. Being pleased to see all the work was worth it, I wanted to pass it along. Best, Terry Attached image(s) |
stewteral |
May 8 2010, 08:32 PM
Post
#2
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Old Member Group: Members Posts: 384 Joined: 4-December 07 From: Camarillo, CA Member No.: 8,424 Region Association: Southern California |
Hey V8 conversion 914ers, I’ve been running my car for some 7 years now and chose to exhaust the radiator out the bottom of the car. It seemed to work fine, but in the 100 degree summer heat of Willow Springs, I was seeing water hitting 250 degrees with fans blazing. We all know that from the 60’s, race cars have vented out to TOP of the hood and it worked well for a friend’s Corvair 327 Chevy we ran at Riverside (142 MPH on the short course back straight). However, I originally didn’t want the car to look too “radical.” When I got the car running it had 11” fender flairs, side scoops, roof scoop and a wing……Ya’ cops won’t notice my car! With some time before my next event, I redid the whole radiator layout where I sealed the bottom of the trunk, HACKED a hole in the hood and fabricated radiator shrouding and an exhaust air dam. I upgraded my fans too. This morning in 60 degree temps, I took the car for a drive AROUND town at low speeds to see if I could keep it from overheating in traffic, as it used to. What I found surprised me: I drove the whole run with NO fans and water temp at 140 degrees. When I was caught by a stop light, the temp went up to 160, but once moving again, it moved back down. I jumped on the freeway and both oil and water dove down to 120 again. EUREKA, I have found my solution! Conclusion: -Of course 120 is lower than desired, in spite of the 180 degree T-stat, but I’m aiming at the right temp ON-Track in Summer. If I want to so some street driving, I can always tape off some of my intake opening. -In the previous configuration, I would have had to run the radiator + oil cooler fans and worry about over heating, now with NO fans, the temps are on the low side. -Before, the oil temp would exceed the water temp by some 30 degrees, now the oil matched the water temps, at least in street driving. -The internal hood bracing defines the hole shape as a trapezoid, so I cut all the width I could get right to left. The back edge is defined by the rear wall of the trunk and from there I measured 12” forward, held my breath, and cut. -If your V8 car is on the edge of overheating and big fans aren’t enough, give this a try. Mine is a pure “racer” design, but our friend byndbad914 came up with an attractive louvered approach that keeps his 500 HP small-block cool. In another design, AndyS created a very attractive molded “air dam” for his LS1 conversion. Being pleased to see all the work was worth it, I wanted to pass it along. Best, Terry Hey Conversion Guys, There is yet ANOTHER benefit to exhausting our the hood of the 914 that I forgot to pass on: the 12" trapezoidal piece defined by the hood support ribs weighed 5 LBS!!! Ah!....More weight reduction!! (IMG:style_emoticons/default/smile.gif) Terry |
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