Power bulge hood vs. flat hood.
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Re: Power bulge hood vs. flat hood.
As far as a weight difference, I would guess no more than 5 lbs including the mounting hardware. I wouldn't mind having them on my car if they actually did anything, but they do nothing aside from try to make the car prettier.
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Re: Power bulge hood vs. flat hood.
I doubt it's even that much of a difference. I have one of each in my barn and I can't feel any weight difference. The power bulge hood actually originated on the 80-81 Turbo TA, where it was not a functional intake but gave some clearance and a place to mount those cool turbo mode indicator lights. On the crossfire equipped TA it was a functional intake, but I think it was only in 82, well have to hear from some CF experts on that one.
I would go for the PB hood if I were you, it's a very unique look and the flat no vent hood makes yours a dead giveaway as a v6.
I would go for the PB hood if I were you, it's a very unique look and the flat no vent hood makes yours a dead giveaway as a v6.
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Re: Power bulge hood vs. flat hood.
I doubt it's even that much of a difference. I have one of each in my barn and I can't feel any weight difference. The power bulge hood actually originated on the 80-81 Turbo TA, where it was not a functional intake but gave some clearance and a place to mount those cool turbo mode indicator lights. On the crossfire equipped TA it was a functional intake, but I think it was only in 82, well have to hear from some CF experts on that one.
I would go for the PB hood if I were you, it's a very unique look and the flat no vent hood makes yours a dead giveaway as a v6.
I would go for the PB hood if I were you, it's a very unique look and the flat no vent hood makes yours a dead giveaway as a v6.
Flat hoods didn't just come on the V6, you know...
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Re: Power bulge hood vs. flat hood.
FWIW...my '84 T/A with the 5.0 Liter H.O. had a functional powerbulge hood. Sounded great when you got into it!
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Re: Power bulge hood vs. flat hood.
I have a factory powerbulge hood that weighs 21lbs..
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Re: Power bulge hood vs. flat hood.
Ditto. Thats the same as mine also. I think 84 is the only year for it though. And if your looking for a good air cleaner lid..... good luck. Ive seen rusted crappy ones sell for like $25. Ive had my out for one for a few weeks now.
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#8
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Re: Power bulge hood vs. flat hood.
Flat hoods didn't just come on the V6, you know...[/QUOTE]
True, but flat hoods (no vent) were only on reg firebirds right, so most must have been v6.
I didn't know they did Carb models with the functional intake.
Of course, there's a reason why all the hood induction stuff was done away with. Once we learned about aerodynamics we realized they are actually reducing air density in the intake.
hence the switch to ram air or CAI front mounted intakes.
True, but flat hoods (no vent) were only on reg firebirds right, so most must have been v6.
I didn't know they did Carb models with the functional intake.
Of course, there's a reason why all the hood induction stuff was done away with. Once we learned about aerodynamics we realized they are actually reducing air density in the intake.
hence the switch to ram air or CAI front mounted intakes.
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Car: 1989-92 FORMULA350 305 92 Hawkclone
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Re: Power bulge hood vs. flat hood.
I didn't know they did Carb models with the functional intake.
Of course, there's a reason why all the hood induction stuff was done away with. Once we learned about aerodynamics we realized they are actually reducing air density in the intake.
hence the switch to ram air or CAI front mounted intakes.
Of course, there's a reason why all the hood induction stuff was done away with. Once we learned about aerodynamics we realized they are actually reducing air density in the intake.
hence the switch to ram air or CAI front mounted intakes.
They just pull cool air instead of warm underhood air.
The front cold air RA setups don't go to positive psi till they are over 100mph anyway.. (from what Im told)
Sooo for most people they are both just cold air kits with a factory cold air kit,(in my bill murry voice from caddy shack "which is nice")
Last edited by TTOP350; 04-14-2012 at 12:56 PM.
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Re: Power bulge hood vs. flat hood.
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Re: Power bulge hood vs. flat hood.
I thought I heard/read that some 82 T/As had the flat hood?? bulge optional?
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Re: Power bulge hood vs. flat hood.
Neat when original, but soon a single side bulge or scoop on a car said you have a 4 or 6 cylinder to the masses.
Course even worse is the acceptance of stick on fake bulges or scoops as they showed up on brand new cars, not just bought at Kmart n stuck on a dirty Esprite in the parking lot.
Course even worse is the acceptance of stick on fake bulges or scoops as they showed up on brand new cars, not just bought at Kmart n stuck on a dirty Esprite in the parking lot.
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Car: 1992 firebird. 1984 Trans Am
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Re: Power bulge hood vs. flat hood.
My 84 ta had a 305 4bl carb with a functional hood.
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Re: Power bulge hood vs. flat hood.
If you can find a bulge hood, then go for it. Weight difference, if any, would be minimal, and you can't beat the look on any thirdgen Firebird, IMO. It's too bad they aren't being reproduced(other than the mythically-elusive fiberglass version supposedly made by VFN), because I think the Power Bulge hood defines the generation.
All '82-'84 Power Bulge hoods were functional, CFI and carb. I'm of the belief that it was a standard feature on Trans Ams. But like TTOP350, I'd also heard that some '82 TAs had flat hoods, though I've never seen one. But if some TAs had flat hoods, then perhaps the bulge hood was part of a "performance package," so that would mean it was possible that not all TAs got one. But I'm pretty sure it wasn't an individually-orderable option.
I shopped for a TA in 1982, and they all had bulged hoods. It was the definitive characteristic of the "all new" Trans Am, which is why it's hard to believe that any TAs would not have had a bulge hood.
When re-introduced on the Formula, I think GM could've/should've made it functional for the 1987 LG4 and the 1988+ LO3. It would've been a nice touch to distinguish a base-V8 Formula from a base model V8 Firebird. I've read some people say GM did do that, but AFAIK, GM didn't do that.
All '82-'84 Power Bulge hoods were functional, CFI and carb. I'm of the belief that it was a standard feature on Trans Ams. But like TTOP350, I'd also heard that some '82 TAs had flat hoods, though I've never seen one. But if some TAs had flat hoods, then perhaps the bulge hood was part of a "performance package," so that would mean it was possible that not all TAs got one. But I'm pretty sure it wasn't an individually-orderable option.
I shopped for a TA in 1982, and they all had bulged hoods. It was the definitive characteristic of the "all new" Trans Am, which is why it's hard to believe that any TAs would not have had a bulge hood.
When re-introduced on the Formula, I think GM could've/should've made it functional for the 1987 LG4 and the 1988+ LO3. It would've been a nice touch to distinguish a base-V8 Formula from a base model V8 Firebird. I've read some people say GM did do that, but AFAIK, GM didn't do that.
Last edited by LAFireboyd; 04-14-2012 at 07:18 PM.
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Re: Power bulge hood vs. flat hood.
They just pull cool air instead of warm underhood air.
The front cold air RA setups don't go to positive psi till they are over 100mph anyway.. (from what Im told)
Sooo for most people they are both just cold air kits with a factory cold air kit,(in my bill murry voice from caddy shack "which is nice")[/QUOTE]
this is exactly where the GM engineers figured out they had been wrong about aerodynamics.
The bulge hood intakes do take in cold air, so on a dyno or on a starting line they are bringing in denser air. What no one had been taking in to account was the effect of the air moving over intakes that face backwards or upwards ( or anyway but straight into the airstream ). If the air does not move straight into the intake, it will create vortices and low pressure centers, reducing the air density and pressure.
Ram air does not create pressure above one atmosphere, like a turbo or supercharger, at least not at any speeds street cars go, but the forward facing intake makes as little vortices as possible and keeps the pressure as close to one atmosphere as possible. Any other intake would have LESS than one atmosphere pressure, the more vortices it generates and the more diverted from the air stream, the lower the pressure will get.
To sum up, reverse or upwards facing intakes will only be as effective as most modern CaIs until they start moving at which time they will become less and less efficient as you speed up.
again, shaker hood scoops and rear mounted intakes are gone for a reason.
I'm not saying its uncool, if I had an HO carb motor w/ original intake I'd prob keep it that way, but it was definitely an engineering error that actually lowers performance.
There are many other examples of ways in which auto engineers (as well as aeronautical engineers) had to abandon some long held design beliefs when the science of aerodynamics became widely understood, ESP with the use of wind tunnels.
But also back to the original question, yes power bulge hoods look awesome on third gens and don't add any noticeable weight.
The front cold air RA setups don't go to positive psi till they are over 100mph anyway.. (from what Im told)
Sooo for most people they are both just cold air kits with a factory cold air kit,(in my bill murry voice from caddy shack "which is nice")[/QUOTE]
this is exactly where the GM engineers figured out they had been wrong about aerodynamics.
The bulge hood intakes do take in cold air, so on a dyno or on a starting line they are bringing in denser air. What no one had been taking in to account was the effect of the air moving over intakes that face backwards or upwards ( or anyway but straight into the airstream ). If the air does not move straight into the intake, it will create vortices and low pressure centers, reducing the air density and pressure.
Ram air does not create pressure above one atmosphere, like a turbo or supercharger, at least not at any speeds street cars go, but the forward facing intake makes as little vortices as possible and keeps the pressure as close to one atmosphere as possible. Any other intake would have LESS than one atmosphere pressure, the more vortices it generates and the more diverted from the air stream, the lower the pressure will get.
To sum up, reverse or upwards facing intakes will only be as effective as most modern CaIs until they start moving at which time they will become less and less efficient as you speed up.
again, shaker hood scoops and rear mounted intakes are gone for a reason.
I'm not saying its uncool, if I had an HO carb motor w/ original intake I'd prob keep it that way, but it was definitely an engineering error that actually lowers performance.
There are many other examples of ways in which auto engineers (as well as aeronautical engineers) had to abandon some long held design beliefs when the science of aerodynamics became widely understood, ESP with the use of wind tunnels.
But also back to the original question, yes power bulge hoods look awesome on third gens and don't add any noticeable weight.
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Re: Power bulge hood vs. flat hood.
Just get a WS6 hood, they look best.
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#22
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Re: Power bulge hood vs. flat hood.
News to me, but I wouldn't be surprised since I know very little about 82-84's vs. 85-92's. Would like to know the answer to this nonetheless, I think that would make it the only pre-4th gen T/A to not get a different hood standard as part of the package.
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Re: Power bulge hood vs. flat hood.
The April 87 issue of Popular Hot Rodding included the article-"Fresh Air Induction For Budget 'Bird", which was the magazine's project 87 LG-4 Formula Firebird. Over a series of articles, the staff had added headers, body panels, head work, and such to boost the performance of the anemic 87(and do I know that!). The article showed how they fabricated an aluminum sheet to seal the rear facing hood bulge for $25. This resulted in a 14 horsepower gain at the rear wheels. Pretty low cost investment.
I will try to post the article if I can get it to upload to the website.
I will try to post the article if I can get it to upload to the website.
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Re: Power bulge hood vs. flat hood.
April 1987 issue of Popular Hot Rodding, Jim Losee is the author.
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Re: Power bulge hood vs. flat hood.
^ I had a 84 t/a that had that exact filter setup, i didnt know it was anything aftermarket, i thought it was just stock, lol
#26
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Re: Power bulge hood vs. flat hood.
The April 87 issue of Popular Hot Rodding included the article-"Fresh Air Induction For Budget 'Bird", which was the magazine's project 87 LG-4 Formula Firebird. Over a series of articles, the staff had added headers, body panels, head work, and such to boost the performance of the anemic 87(and do I know that!). The article showed how they fabricated an aluminum sheet to seal the rear facing hood bulge for $25. This resulted in a 14 horsepower gain at the rear wheels. Pretty low cost investment.
I will try to post the article if I can get it to upload to the website.
I will try to post the article if I can get it to upload to the website.
#28
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Re: Power bulge hood vs. flat hood.
I guess what I was trying to show was that you could make your own cold air set up. Here is the final article of the Budget Bird build, showing the tests and horsepower increases witht he modifications that were done.
#30
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Re: Power bulge hood vs. flat hood.
No wonder it has goofy power numbers, they ran it in overdrive and not 1-1 in 3rdgear
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Re: Power bulge hood vs. flat hood.
Our 92 firebird came stock with a flat hood and it has a V8 305. We switched the hood out for the bulge hood though.
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