rjt76

just wondering if any of you have seen e.t. differences with the hood on and then off? How about mph? Basically how bad does the drag get with it off and how much power do you think that eats up? 1/8 mile?

I ran without mine last year with no hood. my hood was being shipped to me at the time. 8.01 at 87mph

1320_Guy

iTrader: (3)

I have ran with and without one, Didn't notice much of a diffrence. Never swiched during the same night eather. I have a 4" cowl hood, but its not sealed yet so still pulls some hot air with it on.

ZONES89RS

iTrader: (2)

I have never notived a difference, but mine have allways been glass hoods. Now if you went from a steel hood to hoodless maybe?

rjt76

i would think that you would run slower without a hood reguardless of metal or glass style. I would think the drag without it would be great.

smithtc

iTrader: (5)

In the 8th???

You are just beginning to hit the "major" effects of drag. I'd say you may see a "slight" improvement. A mph or two, maybe. Basing this from memory on some research I did several years back. No real world information to provide.

Edit:
To clarify the above...improvement is WITH the hood on, not off.

AlkyIROC

Other than a weight saving, there should be little difference. If anything, you'll probably slow down from wind resistance/turbulence.

I can't find anything in my old NHRA rulebook but under IHRA rules, a hood is mandatory on 11.50 and slower cars.

ZONES89RS

iTrader: (2)

Mandatory for 11,5 or slower? I wonder why?

AlkyIROC

Cosmetics?

The IHRA rulebook is a little sparse on exact rules and can be interpreted different ways. In the ET bracket sections for 11.50 to 13.49 and 13.50 and slower, under Hood, it says mandatory. The faster classes have no section for hood. Under general regulations for hood, it says:

Each car in competition should have a hood over the engine compartment. Side panels may be omitted. Injector tubes may extend through hood, but carburetors may not be openly exposed or uncovered. carburetors, in lieu of hood, must be equipped with a metal flash shield covering the top, back and sides.

Simple terms, slower cars are supposed to have a hood. Faster cars, altereds and dragsters that run a carb, must have something covering the carb such as a scoop, air cleaner etc to control a fire flash.

From reading through that rule, it seems my toilet system because the toilet throttle bodies are considered injector tubes and not a carb (no fuel goes through them), do not need to be covered. I don't have air filters on them and maybe I'll pull the aero scoop off the hood and just have them poke through the cowl. The only reason I installed the short aero scoop was to cover the toilets. There's only about 2" from the top of the toilets to the underside of the scoop.

Maybe I'll fabricate a way to attach the aero scoop with Dzus fasteners to take it off at the track and put it back on to protect the toilets while in transit.

ZONES89RS

iTrader: (2)

Wow, i learned something on that one. Verry interesting man.

automec

a few years ago i was doing some testing with my RA2 hood off. was running 11.6 at 113 on a 100 shot. that evening i put the hood on and went out and ran 12.0 at 110. lucked out with the other guy red lighting on me. 2nd round pulled the hood back off and ran a 11.55 at 113. after that i got a flat steel hood and cut a hole in it for the air filter to race with.

ZONES89RS

iTrader: (2)

Well, that is a actual drag on the car, amazing you lost so much, so with a RA box installed you wouldnt actually be worth the small power gain, wierd?

87_TA

My 82 picked up almost 1/10th, the dominator carb is only about 2" lower than the 2.5" cowl causing restriction. Made one run picking up .08, next pass they warned me I needed a cover for the carb if not using a hood. Been leaving it on since, but still need a solution for the restriction - being that dropping the engine is not an option, I guess that leaves me getting another hood.

Shon Webb

What would be the purpose of you running your car without the hood?

rjt76

as stated in the quote you used my hood was in shipment.

vwdave

In my case where the holley 58mm sticks up over the radiator support, I would theoretically get a ram air effect.

87_TA

In my case as stated, my carb is very close to hood and wanted to see if it was a restriction - and it was.

Shon Webb

It's not much of a difference of racing with it or not. The only problem you may run into is if it's windy out and you running against the wind, but other then that if the track doesn't stop you then it's not much of a difference.

ezstriper

years ago we tested a corvette, did run slower without the hood, when we first took our new car out end of last season, we drove it to tech with no hood, they asked if we had the hood during tech...Rob

KWIK84

iTrader: (5)

At my local, you can go without a hood....as long as you are running an air cleaner assembly. Found this out from a guy who lost his hood @1000' and just ran the rest of the season without one.

DIGGLER

iTrader: (1)

i run without the hood quite frequently because i get tired of wrestling with the pin on hood.
i swear, every time i put the hood back on the car goes slower. lol
however, the car has only made a dozen passes so far.

rjt76

i got a 3" cowl sealed to a carb tray and i am hoping for a better run with the hood. with the stock hood and a drop air cleaner i could feel the horsepower disappear lol. the heat under that hood combined with that crappy drop air cleaner was a joke. also i dumped that flowmaster 80 series ( i hated the sound) I have a dynomax ultraflow to install. The th350 trans change from the 700r4 cant hurt either. I would like to run 7.7 at 90mph+ hopefully. It just seems that the motor and car should be good for itleast that...