[C2] How To Keep Hood Open A Few Inches While Driving
#1
Safety Car
Thread Starter
How To Keep Hood Open A Few Inches While Driving
I remember seeing a piece of hardware online some years ago, but can no longer find it. It's popular among racers in order to keep the rear of the hood rigidly propped open a few inches.
If the hood is simply left unlatched while driving at high speed, it will be buffeted and flap up and down. This device holds it tightly in place.
If the hood is simply left unlatched while driving at high speed, it will be buffeted and flap up and down. This device holds it tightly in place.
#2
Pro
I have always left the hood unlatched on my C1 and C2 Corvettes.
The hoods do not lift until 75 MPH and only then several inches.
The C1s however do pose a problem in warm weather when the cowl vent
is open at the same time that the hood is unlatched. The hot engine air
goes straight into the cockpit through the cowl vent.
The hoods do not lift until 75 MPH and only then several inches.
The C1s however do pose a problem in warm weather when the cowl vent
is open at the same time that the hood is unlatched. The hot engine air
goes straight into the cockpit through the cowl vent.
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ohiovet (03-16-2017)
#3
Team Owner
I only remember seeing some small diameter PVC pipe sections cut off to catch the male hood latch pins and sit in the female latches to give the rear of the hood a couple inches of height....
#4
Melting Slicks
I rarely latch my hood and have never had an issue with it opening.
#5
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St. Jude Donor '07
I have always left the hood unlatched on my C1 and C2 Corvettes.
The hoods do not lift until 75 MPH and only then several inches.
The C1s however do pose a problem in warm weather when the cowl vent
is open at the same time that the hood is unlatched. The hot engine air
goes straight into the cockpit through the cowl vent.
The hoods do not lift until 75 MPH and only then several inches.
The C1s however do pose a problem in warm weather when the cowl vent
is open at the same time that the hood is unlatched. The hot engine air
goes straight into the cockpit through the cowl vent.
and, it doesn't lift at any speed I've driven....
Bill
#7
Melting Slicks
Bill, you probably haven't tried hard enough.
When I has my first '57 years ago, I was probably going around 120 when one hood latch popped open. No big deal-that one was prone to do that sometimes like when going over a bump. But then the other one popped open, and before I could even think about it, the hood raised up about a foot, and then slammed shut, closing both latches. Startled me a bit, although I don't think I ever even let off the gas. I slowed down soon after, though.
Rich
When I has my first '57 years ago, I was probably going around 120 when one hood latch popped open. No big deal-that one was prone to do that sometimes like when going over a bump. But then the other one popped open, and before I could even think about it, the hood raised up about a foot, and then slammed shut, closing both latches. Startled me a bit, although I don't think I ever even let off the gas. I slowed down soon after, though.
Rich
#8
Burning Brakes
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C3 of Year Finalist (appearance mods) 2019
Wow--seriously?? Roads are so rough and twisty here in San Diego that if all hatches weren't battened down, they would soon be shaken from their moorings and tossed in a ditch.
#9
Why
I have always left the hood unlatched on my C1 and C2 Corvettes.
The hoods do not lift until 75 MPH and only then several inches.
The C1s however do pose a problem in warm weather when the cowl vent
is open at the same time that the hood is unlatched. The hot engine air
goes straight into the cockpit through the cowl vent.
The hoods do not lift until 75 MPH and only then several inches.
The C1s however do pose a problem in warm weather when the cowl vent
is open at the same time that the hood is unlatched. The hot engine air
goes straight into the cockpit through the cowl vent.
#10
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St. Jude Donor '07
Owned a C1 and C2 at separate times for 54 total years and NEVER heard of leaving the hood unlatch. Respectfully-what is the rationale behind this??? I really hope this isn't a dumb question. Accidentally drove my 66 once with the hood unlatched and it rattled until I stopped and closed it.
Bull
#11
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St. Jude Donor '07
Bill, you probably haven't tried hard enough.
When I has my first '57 years ago, I was probably going around 120 when one hood latch popped open. No big deal-that one was prone to do that sometimes like when going over a bump. But then the other one popped open, and before I could even think about it, the hood raised up about a foot, and then slammed shut, closing both latches. Startled me a bit, although I don't think I ever even let off the gas. I slowed down soon after, though.
Rich
When I has my first '57 years ago, I was probably going around 120 when one hood latch popped open. No big deal-that one was prone to do that sometimes like when going over a bump. But then the other one popped open, and before I could even think about it, the hood raised up about a foot, and then slammed shut, closing both latches. Startled me a bit, although I don't think I ever even let off the gas. I slowed down soon after, though.
Rich
Bill
Last edited by wmf62; 03-16-2017 at 08:18 PM.
#12
Race Director
#13
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I remember seeing a piece of hardware online some years ago, but can no longer find it. It's popular among racers in order to keep the rear of the hood rigidly propped open a few inches.
If the hood is simply left unlatched while driving at high speed, it will be buffeted and flap up and down. This device holds it tightly in place.
If the hood is simply left unlatched while driving at high speed, it will be buffeted and flap up and down. This device holds it tightly in place.
The hood on my vintage racer is loosely tied down with leather straps. At air speeds of about 100 MPH and higher, the hood will rise and stay up until the air speed drops. It doesn't get buffeted. It doesn't flap. It just stays up.
Jim
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65tripleblack (03-17-2017)
#14
Drifting
As a long tme Hot rodder and racer, we try everything to go faster. Some work, some do not. I tried the hood up thing some years back at the track. Final results....
ET was within thousands, temperature was the same. You do not try, you do not know.
ET was within thousands, temperature was the same. You do not try, you do not know.
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65tripleblack (03-17-2017)
#16
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That has not been my experience.
The hood on my vintage racer is loosely tied down with leather straps. At air speeds of about 100 MPH and higher, the hood will rise and stay up until the air speed drops. It doesn't get buffeted. It doesn't flap. It just stays up.
Jim
The hood on my vintage racer is loosely tied down with leather straps. At air speeds of about 100 MPH and higher, the hood will rise and stay up until the air speed drops. It doesn't get buffeted. It doesn't flap. It just stays up.
Jim
#17
Safety Car
Thread Starter
Owned a C1 and C2 at separate times for 54 total years and NEVER heard of leaving the hood unlatch. Respectfully-what is the rationale behind this??? I really hope this isn't a dumb question. Accidentally drove my 66 once with the hood unlatched and it rattled until I stopped and closed it.
It is to see whether or not it makes any difference in the inlet air feed to the carb.
If I model my engine in Engine Analyzer 3.5 using SAE (77 degree F.) air, it develops 482 flywheel HP (which correlates to the 412 RWHP the dyno showed running hood open and fan blowing). If I model it using 140 degree air, it develops 455 flywheel HP.
I have a feeling that the true feed that most engines get is a mix of hot and outside air. I want to see if opening the rear of the hood makes any difference.
BUT, if you read VetRod's post, it looks like he's already done the work.
Last edited by 65tripleblack; 03-17-2017 at 11:54 AM. Reason: Correct horsepower readings
#18
Team Owner
The stainless steel "cookie sheets" in the 63 hood were allegedly introduced to be perforated grills to allow trapped under-hood air to escape to reduce lift (and maybe better cooling) - so somebody thought it was an issue for some reason.
The green eyeshade GM backoffice types ruled it too expensive so the metal pieces became solid sheets and one-year-only decorations.
The green eyeshade GM backoffice types ruled it too expensive so the metal pieces became solid sheets and one-year-only decorations.
Last edited by Frankie the Fink; 03-17-2017 at 10:27 AM.
#19
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I would be more inclined to fix an overheating problem than to drive around with the hood open. I drive with mine closed up tight. No rattles, and doesn't look odd.
#20
Safety Car
Thread Starter
I'm fairly sure that Jim L, 427hotrod and others do this to relieve underhood pressure at high speeds to alleviate lift.
Drag racers try to get cooler air into the carb(s). Some like vetrod say it makes no difference after trying. Others, I'm not so sure, so I'd like to try for myself.
The underlined part of my last post is what I'd like to check into. Just how much power is cowl induction really worth? Did the L88 air box hood make a significant difference? If a sealed hood is supplying the carb with a mix of ambient and heated air, then cold air induction is only "half" as effective as one might think.
Last edited by 65tripleblack; 03-17-2017 at 11:57 AM.