C5 Corvette Modifications Primer
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Thanks folks 
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From: Bel Air (by way of Fort Worth, TX) Maryland
St. Jude Donor '12 thru '21
Corvette Modifications Primer : A few things to consider if you wish to modify your Corvette for High Performance
So you want to modify your C6 or C5 Corvette for high performance. Here are some things that you should consider first.
What is your driving style? Are you a drag racer? Autocross? Road racer? Weekend warrior? Show car? Stoplight to stoplight? Or simply highway fun? Or a combination of all or some of these choices?
How you drive and enjoy your Corvette will directly determine what modification you should make to your Corvette.
Nothing is free. Every modification you make to your stock Corvette will involve some kind of compromise. You are not going to make 800 rear wheel horsepower and get 30 miles per gallon with a whisper quiet exhaust as well as drive and idle like stock. That is not going to happen.
The trick is to be totally honest with yourself and decide what compromises you can live with and which ones you cannot. For example, if you want to achieve 500rwhp naturally aspirated, expect a big cam with a loping idle. Expect to lose some fuel efficiency. Expect your Corvette to not drive like stock. Expect to void (at least in part) your GMPP warranty.
You can start with simple bolt-ons like an aftermarket air filter, long tube headers and cat-back exhaust system. The next logical step is a camshaft only upgrade or heads and camshaft. Along with the bolt-ons, you can be comfortably at the 425-450rwhp range, all naturally aspirated. Or you could bypass the bolt-ons and simply have a supercharger or twin turbocharger system installed. An alternative to bolt-on might be rear gears (along with a stall converter for the automatics). Gears can also compliment your other modifications.
It all depends on what you wish to achieve.
As you increase the stock Corvette from it's 300-340rwhp (C5-C6) or 435rwhp (C6 Z06) to circa 550rwhp on the stock bottom end, expect to have to upgrade other aspects of your drivetrain, cooling and suspension. Remember, nothing is free.
Beyond 550rwhp, we strongly recommend a forged engine as you will be on borrowed time. At this point, your clutch/stall converter will have to be upgraded along with torque tube connectors, transmission and differential. Cooling must be addressed as well as the always overlooked and often forgotten bulletproof fuel system. At this point, methanol injection for boosted applications is almost mandatory. Suspension, brakes, wheels and tyres should also be seriously addressed, along with additional safety systems like a 6 point or better rollcage and so on.A Corvette that is very fast is no fun if it also does not handle and stop.
High performance is not a cheap hobby and it is best to be very aware of this fact going in so you do not encounter any surprises.
But no matter what your budget, we can tailor a system to suit your current and future needs. So please drop us a line or give us a call to discuss your Generation 5 & 6 Corvette high performance needs.
Phone: 772 539 0997
Email: info@englandgreen.com
AIM: englandgreeninc
Stephen
Very refreshing to get straight information from a top-notch tuner
I am not planning any radical engine mods like H/C or S/C or etc. I use my ride as a GT/DD and if I had 550HP it would really be a waste since I don't drive my car that way and can't justify spending the cash for such upgrades.
My question is, what sort of "enhancements" would you suggest for a Vette owner like myself? I know that may sound like a dumb question, but I just want to enhance my highway driving experience if that is possible. I have Michelin RFs, A Corsa Touing exhaust and a Z06 air box as my only "mods". Thanks
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Suspension and brakes makes a huge difference in the daily enjoyment of your baby, with a relatively low price point and a big return on your investment.
Look into Hawk HPS brake pads along with stainless brake lines and fresh DOT 3 fluid. Brakes will feel like a different car.
Suspension; lower and add Bilstein Sports with some decent sway bars with metal end links like the 2004 Z06 sways.
Daily enjoyment will rise with no detriment to reliability or gas mileage.
Stephen
Look into Hawk HPS brake pads along with stainless brake lines and fresh DOT 3 fluid. Brakes will feel like a different car.
Suspension; lower and add Bilstein Sports with some decent sway bars with metal end links like the 2004 Z06 sways.
Daily enjoyment will rise with no detriment to reliability or gas mileage.
Stephen
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Joined: Jan 2007
Posts: 114
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Suspension and brakes makes a huge difference in the daily enjoyment of your baby, with a relatively low price point and a big return on your investment.
Look into Hawk HPS brake pads along with stainless brake lines and fresh DOT 3 fluid. Brakes will feel like a different car.
Suspension; lower and add Bilstein Sports with some decent sway bars with metal end links like the 2004 Z06 sways.
Daily enjoyment will rise with no detriment to reliability or gas mileage.
Stephen
Look into Hawk HPS brake pads along with stainless brake lines and fresh DOT 3 fluid. Brakes will feel like a different car.
Suspension; lower and add Bilstein Sports with some decent sway bars with metal end links like the 2004 Z06 sways.
Daily enjoyment will rise with no detriment to reliability or gas mileage.
Stephen
Administrator
Joined: Jun 2007
Posts: 66,408
Likes: 2,060
From: Bel Air (by way of Fort Worth, TX) Maryland
St. Jude Donor '12 thru '21
Suspension and brakes makes a huge difference in the daily enjoyment of your baby, with a relatively low price point and a big return on your investment.
Look into Hawk HPS brake pads along with stainless brake lines and fresh DOT 3 fluid. Brakes will feel like a different car.
Suspension; lower and add Bilstein Sports with some decent sway bars with metal end links like the 2004 Z06 sways.
Daily enjoyment will rise with no detriment to reliability or gas mileage.
Stephen
Look into Hawk HPS brake pads along with stainless brake lines and fresh DOT 3 fluid. Brakes will feel like a different car.
Suspension; lower and add Bilstein Sports with some decent sway bars with metal end links like the 2004 Z06 sways.
Daily enjoyment will rise with no detriment to reliability or gas mileage.
Stephen
CF "Young" Senior Member
Joined: Feb 2005
Posts: 4,034
Likes: 26
From: Cupertino CA
St. Jude Donor '12
A nice addition to this would be the (expected) price range of each jump in power. What the low / high range you expect to pay for the parts / tune at each level, and what hidden costs you can expect to incur.
Regardless of that, thanks EG for a great post to open up the eyes of many to the inherent problems with "MORE POWER~".
Regardless of that, thanks EG for a great post to open up the eyes of many to the inherent problems with "MORE POWER~".
Thread Starter
Supporting Tuner
Joined: Sep 2004
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
CI 6-7-8-9-10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Great information here and I'm reading with considerable interest, freshly bitten by the mod bug. Can you comment on intake and exhaust? I keep reading here that factory intake isn't great. Am thinking of Vararam or like up front and Corsa Touring exhaust on 1998 Coupe...
A SLP Blackwing, Vararam, Halltech Stinger, etc. are all light years better than the stock intake filter system.
Catback mufflers should always be viewed as 'aural bling' and should never purchased with performance in mind. Buy catbacks because you like how they sound - not for the alleged performance gains (minimal at best).
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
As a general (and quite vague) rule of thumb, expect to pay anywhere from $50 to $150 per horsepower gained over stock.
How does that equate?
Stock C5 (non-Z06) is circa 300 rear wheel horsepower (rwhp). Add an intake filter system (circa $500), catback mufflers ($1000), complete header system with high flow cats, x-pipe and mid pipes ($1800), complete camshaft system (circa $2000), and a good PCM tune ($500).
You have gained perhaps 80-120rwhp.
Your car is now anywhere from 380-420rwhp depending on the condition of the original engine and the camshaft chosen.
That just cost you $5,800 = or roughly $58 per horsepower. And this is assuming you did all the work yourself!!!
From there, it gets considerably more expensive - heads are circa $2500 for just the parts... a supercharger system is around $6000+... and so on.
And then you have the "supporting modifications" that add zero overall power, but add up in cost quickly - cooling, engine monitoring, fuel system, drivetrain, suspension, brakes, safety.... and so on.
We all love to lament the so called "Corvette Tax" and say that "Mustangs" or "Camaros" or "Supras" do not cost as much..... don't they?
To do any system correctly is costly, it doesn't matter what platform you use - Y-Body (Corvette), F-Body (Camaro/Trans Am), Fox-Body (older Mustangs), Imports et al.
None of them are cheap.
Make no mistake, performance is expensive in time as well as money.
That's why I recommend you have a viable plan going in - so you can avoid the pitfalls, reversals and problems.
Stephen
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Safety Car
Joined: Mar 2006
Posts: 4,554
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From: Godfrey IL
Corvette Modifications Primer : A few things to consider if you wish to modify your Corvette for High Performance
So you want to modify your C6 or C5 Corvette for high performance. Here are some things that you should consider first.
What is your driving style? Are you a drag racer? Autocross? Road racer? Weekend warrior? Show car? Stoplight to stoplight? Or simply highway fun? Or a combination of all or some of these choices?
How you drive and enjoy your Corvette will directly determine what modification you should make to your Corvette.
Nothing is free. Every modification you make to your stock Corvette will involve some kind of compromise. You are not going to make 800 rear wheel horsepower and get 30 miles per gallon with a whisper quiet exhaust as well as drive and idle like stock. That is not going to happen.
The trick is to be totally honest with yourself and decide what compromises you can live with and which ones you cannot. For example, if you want to achieve 500rwhp naturally aspirated, expect a big cam with a loping idle. Expect to lose some fuel efficiency. Expect your Corvette to not drive like stock. Expect to void (at least in part) your GMPP warranty.
You can start with simple bolt-ons like an aftermarket air filter, long tube headers and cat-back exhaust system. The next logical step is a camshaft only upgrade or heads and camshaft. Along with the bolt-ons, you can be comfortably at the 425-450rwhp range, all naturally aspirated. Or you could bypass the bolt-ons and simply have a supercharger or twin turbocharger system installed. An alternative to bolt-on might be rear gears (along with a stall converter for the automatics). Gears can also compliment your other modifications.
It all depends on what you wish to achieve.
As you increase the stock Corvette from it's 300-340rwhp (C5-C6) or 435rwhp (C6 Z06) to circa 550rwhp on the stock bottom end, expect to have to upgrade other aspects of your drivetrain, cooling and suspension. Remember, nothing is free.
Beyond 550rwhp, we strongly recommend a forged engine as you will be on borrowed time. At this point, your clutch/stall converter will have to be upgraded along with torque tube connectors, transmission and differential. Cooling must be addressed as well as the always overlooked and often forgotten bulletproof fuel system. At this point, methanol injection for boosted applications is almost mandatory. Suspension, brakes, wheels and tyres should also be seriously addressed, along with additional safety systems like a 6 point or better rollcage and so on.A Corvette that is very fast is no fun if it also does not handle and stop.
High performance is not a cheap hobby and it is best to be very aware of this fact going in so you do not encounter any surprises.
But no matter what your budget, we can tailor a system to suit your current and future needs. So please drop us a line or give us a call to discuss your Generation 5 & 6 Corvette high performance needs.
Phone: 772 539 0997
Email: info@englandgreen.com
AIM: englandgreeninc
Stephen
Safety Car
Joined: Mar 2006
Posts: 4,554
Likes: 35
From: Godfrey IL
Stephen,
You are being very honest about what one should expect when they attach the mods. That's why we miss your input and your threads on this forum.
I was drawn to your Grond Chronicles very early on when I joined, and I understood what you were doing. I learned a lot (and lived vicariously through you
).
Now that you are in the tuner business, I still don't see you steering anyone to mods just to make a quick buck. Good Man!
You are missed here and we hope to hear from you more often.
Steve
You are being very honest about what one should expect when they attach the mods. That's why we miss your input and your threads on this forum.
I was drawn to your Grond Chronicles very early on when I joined, and I understood what you were doing. I learned a lot (and lived vicariously through you
).Now that you are in the tuner business, I still don't see you steering anyone to mods just to make a quick buck. Good Man!
You are missed here and we hope to hear from you more often.
Steve
Thread Starter
Supporting Tuner
Joined: Sep 2004
Posts: 51,896
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
CI 6-7-8-9-10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Life was just too short to be constantly defending myself against their unsubstantiated, baseless and scurrilous antics.
I'll post again these sections and see how it goes.
Stephen
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
ttt
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
ttt
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
PM savewave, cor07vette or Grumpy.
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St. Jude Donor '03-'04-'05-'06-'07-08-'09
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Nicely done my friend Wish I was closer 
Wish I was closer
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From: The Great Truth: "There ain't no free lunch"
St. Jude Donor '08-'09-'10-'11
Ahem!!! As I posted originally (since been lost in cyberspace) "Very informative post, thanks for taking the time". Seems like a lot of folks agree....Congratulations
Tom
Tom
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Joined: Feb 2006
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From: Sarasota Florida
Good.... no make that GREAT advice EG. It sure is good to see you posting on the C5 section again. I think I speak for 99.9% of us when I say we miss your wisdom, honesty and sense of humour.