Hello!

I'm interested in getting a cam for my 2001 C5 Corvette. I want to keep it relatively reliable and still pretty efficient in gas, cause its the automatic (am I delusional for this? Does such a thing even exist?). I'm primarily looking to get that chop sound. Power isn't the goal here. I already have the Borla Attack catback exhaust, and I'll get long tube headers at the same time as the cam.

Doing this cause I'm gonna have to pull out the engine to replace those damm rear main seals, also to replace the harmonic balancer. Rather do the cam and headers now when the engine is out.

Any recommendations or tips would be fantastic.

Have a great rest of your day!

 

What rear gears does it have?

 

It's got the G92 (3.15) performance auto.

 

Assuming it's factory - either 2.73 or 3.08 gears

A choppy cam won't play well with your factory gears or torque converter. If you're worried about fuel efficiency - I would encourage you to go another way.

 

Which way would you recommend? I'm thinking just headers after a bit of research.

 

If the motor is coming out anyways , a small cam is not a bad way to go.
I just did a Comp FSL cam with some CNC ported 243 heads and the car pulls hard to 6500RPM with a factory idle.

If you want to wake up how the car feels, rear gears will do more than anything else. Gears multiply torque, the standard rear on the C5 Automatic is a 2.73 final drive ratio
imagining if have 350 ft/lbs of torque and are in 3rd with with your automatic transmission (1:1 ratio)
350 x 2.73 = 956 ft/lbs of torque at the wheels

If you swap to 3.73 gears: 350 x 3.73 = 1306 ft/lbs of torque at the wheels.

With deeper gears, you can get away with more cam... but I just spend a few thousand dollars of your money already

 

Try the Green above if you are so inclined.
Where are you located?

 

I just put a BTR stage 3 in mine.

Only driven it about 10 miles so far, because Minnesota...
I love it.

But I also have a 6sp with the 3:42's.

YMMV

 

I think I misunderstood your post above. I can’t imagine how, lol, but I did…. Reading your other thread, you mentioned you do not want to degrade your mpg. Well, I get that 👍

You shouldn’t lose any mpg with headers, but will need to have it tuned, so be mindful that $700-ish for tune and dyno.

The tuner will also tune out the AIR system. The AIR system is designed to help heat the pup cats up quicker, but you won’t have the pup cats(pre cats) after the header install anyway. So now would be the time to yank that gear out.

Let us know how your project goes and post some pics. Good luck!

 

[QUOTE=Tommy Bahama Fan;1609502484]I just put a BTR stage 3 in mine.

Only driven it about 10 miles so far, because Minnesota...
I love it.

But I also have a 6sp with the 3:42's.

YMMV[/

Tommy, I’m also in Minnesota and I’m considering a similar setup for my 01 base manual.



How do I confirm what rear gear ratio my car has for sure? I’ve seen references to the 3.42 gears, but I want to verify what’s actually in the car before deciding on a cam.



This is my first Corvette and I’m still learning the platform. The car has about 180k miles, so right now I’m working through some maintenance items to get it dialed in for spring (tracking down a couple small oil/coolant leaks, fluids, etc.). Once everything is sorted, I’m planning long tubes and an X-pipe, and then eventually looking at cam options.



Any advice on confirming the rear gear ratio or cam choices that work well with the stock gearing would be appreciated

 

[QUOTE=mhasbrouck24;1609503473]Look inside either the glove box (1999-2004) or the rear compartment (1997-1998) for the Service Parts Identification sticker. If it's a manual, it will always be a 3.42 stock (you'll see GU6). If it's an auto, look for either GU2 or G92/GU5.

GU2 - is the 2.73
G92/GU5 - is the 3.15

 

KyleDrives is correct. All manuals have the 3:42 from the factory.

 

Gotcha are the 3.42 the ideal gearing ratio to have a somewhat aggressive cam or do many manual owners change their ratio?

 

The cam rpm range is important, I replaced the previous Comp cam that had an rpm range of 1900-7000 with a milder Comp cam # 54-412-11 that has a 1200-6000 range. The older cam really woke up after 4k rpm but was just ok below that. Daily driving has improved a lot with this new cam change, all the systems work better together now. The car has 3:15 gears, long tube headers, AFR cylinder heads, a mild torque converter and a shift kit with an HP Tuners transmission program. The best change of all was the HP Tuners download for the transmission 15 years ago that got rid of the part throttle acceleration lag.

 

I always go gears first.

An old hot rod adage: Start from the back and work your way forward. Not suggesting doing this blindly, but if you have a general idea of your end goal this allows you to enjoy each progression without downside; manual OR auto. This as opposed to living with a built engine that is mismatched to an underperforming trans/rear setup.

2004 mn6…
First thing I modded on my car was 4.10 gears and made a huge improvement with a stock engine. Later added a mild cam and 243s and they get it on with the lower gears. Next up is headers.

I also had a new 2003 mn6 vert back in the day, first thing was 3.90 gears. Better for highway commuting, but still really woke that car up as well 👍.

 

Comp cams has idle clips in the cam detail page gallery.

https://www.compcams.com/xfi-rpm-216...en-iii-iv.html

 

Thank you this is helpful!

 

In general - the numerically higher the gears, the more cam duration you can get away with.

Over simplifying here
All gas engines have a 'sweet spot' where they make maximum horsepower. This is usually a approx 2000RPM range that you are trying to get into the right spot.
As a general rule, the higher duration number of a cam, the higher in the RPM range that sweet spot will occur.
The way that Horsepower is calculated <HP = (Torque x RPM) / 5252 > the higher RPM peak torque is produced, the higher a horsepower number will be
300# torque @ 5000 RPM = 286HP 300# torque @ 7000 RPM = 400HP
SO we all want to build high RPM screamers... right...

The downside is by gaining high RPM torque, you are trading away lower RPM torque. Trade away too much and the car is boggy on the street. As a side effect, the higher RPM peak torque occurs, the more peaky a engine tends to get. An engine that rev's to 9000RPM will probably make very little torque at 1500RPM.

The gears are a bit of a hack for this. As I talked about in my previous post, gears multiply torque. If you've traded away a bunch of low RPM torque to the engine gods with a high duration cam, you can get some of it back with the gears. Along with this, you use the gears to lower the MPH/engine RPM ratio so you don't have to be going 100MPH to get 'on' the cam. Spinning higher RPM at a given MPH will increase fuel consumption.

It's all an eco system, and this ain't the half of it.

 

I have a friend who purchased a 1999 FRC last year. He installed a BTR Red Hot cam in it, plus long tube headers.

It's quite nice. It chops a little at idle and at low RPM too. It may not be quite what you're looking for since you have an automatic, but it woke up the venerable LS1 at high RPM. It dyno'd 385 at the wheels after tuning.

 

Given that you're not looking for a performance upgrade, you don't want to lower your MPG, and you really just want a better sound, I think think some of the things mentioned above wouldn't be the best fit for you. You DEFINITELY don't want anything like a BTR stage 3. There's also no need to do a gear swap. You already have 3.15 gears, and the main reason for a gear swap would be performance, which you already said is not what you're looking for. A gear swap will have absolutely no impact on your sound.

In general, any cam that's going to create a lot of chop will have a negative impact on your gas mileage. Headers alone can definitely make a noticable difference to your sound. However, headers alone don't create chop. Also, a note regarding headers. You don't necessarily delete your AIR system. It will depend on what headers you get. Depending on where you live, you may need to keep your AIR system in order for your car to pass inspection/emissions.

Given your stated goals, if you do decide on a cam, you'll likely want something relatively mild. However, if you just want a better sound, but don't necessarily need chop, just headers will probably be your best option.