I'd say you'd probably see a 35-45 rwhp increase. 
Bolt On HP Increases
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Racer
Joined: Aug 2006
Posts: 403
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From: Huntsville Alabama
Bolt On HP Increases
Just curious, let's say a Vararam gives 25hp, a power duct gives 7hp, catback gives 5 hp, headers give 30hp, etc. (guessing at advertised hp)
From these bolt-ons, and assuming they are capable of delivering the advertised HP, would the additional HP in the example be at 72hp or does one bolt-on deminsh another bolt-ons performance? Hopefully I articulated the question correctly.
From these bolt-ons, and assuming they are capable of delivering the advertised HP, would the additional HP in the example be at 72hp or does one bolt-on deminsh another bolt-ons performance? Hopefully I articulated the question correctly.
Burning Brakes
Joined: Nov 2011
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From: Chandler, AZ
St. Jude Donor '12
I don't think they add up that way, they compliment each other and only under IDEAL condition do they deliver the HP they say. So my guess would be with all that you stated maybe 45 hp tops?
Last edited by Todds427; Dec 4, 2011 at 08:49 AM.
Melting Slicks
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I doubt you'll see 72 hp from those mods. The suggested 35-40 might be pretty close.
Team Owner
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St. Jude Donor '09-'10, '14
Some add ons work with each other to gain the maximum numbers advertised. Like the vararam provides for more air. headers enable you to extract that air more efficiently. so you won't see 55hp increase on those two.
BUt with just a good axleback system you will extract more air efficiently so it will boost the numbers some. I think 5 is a little low though.
Same thing with headers. Headers alone will help, but again you won't be able to add 30 for headers and your 5 for the axleback.
Say you had headers and stock exhaust. The stock exhaust would prevent you from gaining the full 30 on the headers. But if you had a good exhaust, it would enable you to get the full 30 on your headers. So if you have vararam, headers and exhaust you should be able to get a full 30+. But without all three, you won't see the full potential of any single one. Air intake+air extraction system=quality air intake and extraction=more hp. That's why they advertise up to!
Simplistic but I hope you get the idea.
BUt with just a good axleback system you will extract more air efficiently so it will boost the numbers some. I think 5 is a little low though.
Same thing with headers. Headers alone will help, but again you won't be able to add 30 for headers and your 5 for the axleback.
Say you had headers and stock exhaust. The stock exhaust would prevent you from gaining the full 30 on the headers. But if you had a good exhaust, it would enable you to get the full 30 on your headers. So if you have vararam, headers and exhaust you should be able to get a full 30+. But without all three, you won't see the full potential of any single one. Air intake+air extraction system=quality air intake and extraction=more hp. That's why they advertise up to!
Simplistic but I hope you get the idea.
Last edited by RetiredSFC 97; Dec 4, 2011 at 12:28 PM.
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Melting Slicks
Joined: Feb 2001
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From: Northville, MI
If you were to but the engine on a dyno you would find out the Veraram, power duct and mufflers would add 0 hp while the Headers might at 7-20 depending on design. At the track a good Veraram system ( sealed engine comparment items) would add about 0.1 sec (about 25-30 hp) with no other changes due to the cooler, more dense air going into the chambers. The Power duct will slow the velocity of the air entering the engine and loose 5 hp. The real change would be a quality tune to the PCM to allow the Veraram and Headers to do their work. An exhaust system after cats would yield 0 hp over a Z06 exhaust which GM found added about 2.5 hp on the Z06 engine. We have had club members who worked at the Proving grounds, P&M, Rouch, etc and there often mentioned the above improvements in their testing. A chassis dyno is dependent on settings, day etc and gives varying results. A few product companies were known to make a base run and then add their product and continually tune the car to get the best advertised results. You want to get a good baseline, go to a drag strip and make your changes and test immediately. Trap speed will give you a good indications of real HP.
Race Director
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If you were to but the engine on a dyno you would find out the Veraram, power duct and mufflers would add 0 hp while the Headers might at 7-20 depending on design. At the track a good Veraram system ( sealed engine comparment items) would add about 0.1 sec (about 25-30 hp) with no other changes due to the cooler, more dense air going into the chambers. The Power duct will slow the velocity of the air entering the engine and loose 5 hp. The real change would be a quality tune to the PCM to allow the Veraram and Headers to do their work. An exhaust system after cats would yield 0 hp over a Z06 exhaust which GM found added about 2.5 hp on the Z06 engine. We have had club members who worked at the Proving grounds, P&M, Rouch, etc and there often mentioned the above improvements in their testing. A chassis dyno is dependent on settings, day etc and gives varying results. A few product companies were known to make a base run and then add their product and continually tune the car to get the best advertised results. You want to get a good baseline, go to a drag strip and make your changes and test immediately. Trap speed will give you a good indications of real HP.
Race Director
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Very similar to my results. My best thru the manifolds with gutted cats was 12.89@109.97mph. Sounds like you'd have me slightly out of the hole, and I wouldn't quite catch you, either. Isn't it amazing how these cars respond to boltons? Back when I was a young guy, you had to have one tremendous musclecar to run in the 12s, and they sure as Hell didn't get 25mph, either!!
Drifting
Joined: Jul 2004
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From: Pingree Grove IL
I’ve had this setup for a long time now, headers, intake, exhaust, tune. I might be going a little further next year or spring of 2022. 373 or 390 gears and a vig3200 converter, installed by finish line performance in Plainfield IL. I want it, just haven’t pulled the trigger yet. I could only hope for a low 12 on street tires.