C5 Cam Shaft Upgrade
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You could, just depends on how you use the car, since the 3.90 will increase your normal city rpm’s about 200 rpm.
If it were me, I’d stick with 3.73. Here’s some figures:
Gear. Ratio 3.73. RPM. Speed. Ratio 3.90. RPM.
1…………………….5076.….35……………….5308.
2. ……………..……5323..…70………………. 5556
3. …………………..5163. ..110……………. 5399
4. …………………..5257… 160. ………………5497
4. …………………..2300. …70……………….. 2405
You could pull more rpm…. For my interests, I wanted a cam that would be happy in the 5000-5500 range, with 6000 attainable, and how I feel it should have come from the factory.
If you really want to turn up the wick, you’ll want upgrades to the trans and converter, and headers. In that case your in A&A territory cost wise all in with the gear swap, which what all the blower guys will say and they’d be right.
The thing about doing deeper, but not too deep, and then a mild cam is that you can stop there and drive it a while. The LS6 Power Max and 3.73’s is a pretty big jump alone, but not too radical if you want a blower some day. The 3.73 gears would spool up that centrifugal blower like right now.
If it were me, I’d stick with 3.73. Here’s some figures:
Gear. Ratio 3.73. RPM. Speed. Ratio 3.90. RPM.
1…………………….5076.….35……………….5308.
2. ……………..……5323..…70………………. 5556
3. …………………..5163. ..110……………. 5399
4. …………………..5257… 160. ………………5497
4. …………………..2300. …70……………….. 2405
You could pull more rpm…. For my interests, I wanted a cam that would be happy in the 5000-5500 range, with 6000 attainable, and how I feel it should have come from the factory.
If you really want to turn up the wick, you’ll want upgrades to the trans and converter, and headers. In that case your in A&A territory cost wise all in with the gear swap, which what all the blower guys will say and they’d be right.
The thing about doing deeper, but not too deep, and then a mild cam is that you can stop there and drive it a while. The LS6 Power Max and 3.73’s is a pretty big jump alone, but not too radical if you want a blower some day. The 3.73 gears would spool up that centrifugal blower like right now.
Instructor
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Thanks forum for all the info, great thread - I've been considering a cam swap on my 01 vert with a manual and the 3:42 gears - would like to do the supercharger but I 'm not sure I want to get into a hood swap and all the other ancillary changes and the $$ involved just doesn't seem like something i could justify - with just the cam swap what else would you need to switch out? At what point does the added HP (thinking if I went with the supercharger) suggest getting a more robust tranny? Rear-end?
Thinking if I could get around 400 or so to the wheels I would be happy ( well at least happier) - I've got an Air-raid cold air, Corsa X pipe and tigershark tips but haven't had it dyno tuned after they were put in
Any and all suggestions welcome
Thinking if I could get around 400 or so to the wheels I would be happy ( well at least happier) - I've got an Air-raid cold air, Corsa X pipe and tigershark tips but haven't had it dyno tuned after they were put in
Any and all suggestions welcome
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To upgrade to the 3.73 rear gears, do you simply swap out the gears in the existing rear differential or do you need to purchase an entirely new rebuilt rear differential?
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Most try to buy a low mile, 3 rib C5 Z06 diff, which come with 3.42 gears. To get 3.73 gears, you're either going to have to buy just the gears (and carrier, if you don't have the 3.15 diff now), or buy a whole new/reman diff from a vendor.
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In searching on Summit for 2004 Corvette, they provide a lot of options and size i.e. 7.5" vs. 8.5". Any recommendations on brand/size?
https://www.summitracing.com/search?...d=3.73%20gears
Also, I've noticed some gear sets are listed as "heat treated" and "non heat treated". What's the value of the higher cost "heat treated" gear sets? Are those specifically treated for drag racing or track applications?
https://www.westcoastcorvette.com/pr...17022964924462
Last edited by MSG C5; Feb 3, 2022 at 04:25 PM.
Team Owner
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St. Jude Donor '05
Id do a mild cam and maybe longtube headers. Get a retune and call it a day.
Get a flat rate price from the guy in writing first. Know you ought to change valvesprings and seals while its being done
For true street cams I like to keep the duration@050 somewhere in the low-high teens max. Lots of torque good idle.
Get one with a gentle ramp to give longevity and by all means you want a cam on a steel core not cheap cast iron
Your stock lifters are fine..with 25k mi you got yrs of driving to do!
Get a flat rate price from the guy in writing first. Know you ought to change valvesprings and seals while its being done
For true street cams I like to keep the duration@050 somewhere in the low-high teens max. Lots of torque good idle.
Get one with a gentle ramp to give longevity and by all means you want a cam on a steel core not cheap cast iron
Your stock lifters are fine..with 25k mi you got yrs of driving to do!
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Thanks.
In searching on Summit for 2004 Corvette, they provide a lot of options and size i.e. 7.5" vs. 8.5". Any recommendations on brand/size?
https://www.summitracing.com/search?...d=3.73%20gears
Also, I've noticed some gear sets are listed as "heat treated" and "non heat treated". What's the value of the higher cost "heat treated" gear sets? Are those specifically treated for drag racing or track applications?
https://www.westcoastcorvette.com/pr...17022964924462
In searching on Summit for 2004 Corvette, they provide a lot of options and size i.e. 7.5" vs. 8.5". Any recommendations on brand/size?
https://www.summitracing.com/search?...d=3.73%20gears
Also, I've noticed some gear sets are listed as "heat treated" and "non heat treated". What's the value of the higher cost "heat treated" gear sets? Are those specifically treated for drag racing or track applications?
https://www.westcoastcorvette.com/pr...17022964924462
Call Motive gears. They are one of two US manufacturers of C5 Corvette gears, and the other, Yukon, just got into the game. They sell on sites like Jegs, etc., but I would call them direct first and get all your questions and concerns addressed.
There are various levels of heat treating. The hardest gears can handle the most power, but are also more brittle and have a shorter life span. In other words they are for racing.
All Motive’s gears are hardened and they are the go-to source.
https://www.motivegear.com/auto-part...nesize%3A_ANY_
Heres the Motive gears on Summit:
https://www.summitracing.com/parts/m...ette/year/2004
Last edited by vette4fl; Feb 3, 2022 at 05:05 PM.
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Pretty sure you’re looking for 8.25.
Call Motive gears. They are one of two US manufacturers of C5 Corvette gears, and the other, Yukon, just got into the game. They sell on sites like Jegs, etc., but I would call them direct first and get all your questions and concerns addressed.
There are various levels of heat treating. The hardest gears can handle the most power, but are also more brittle and have a shorter life span. In other words they are for racing.
All Motive’s gears are hardened and they are the go-to source.
https://www.motivegear.com/auto-part...nesize%3A_ANY_
Heres the Motive gears on Summit:
https://www.summitracing.com/parts/m...ette/year/2004
Call Motive gears. They are one of two US manufacturers of C5 Corvette gears, and the other, Yukon, just got into the game. They sell on sites like Jegs, etc., but I would call them direct first and get all your questions and concerns addressed.
There are various levels of heat treating. The hardest gears can handle the most power, but are also more brittle and have a shorter life span. In other words they are for racing.
All Motive’s gears are hardened and they are the go-to source.
https://www.motivegear.com/auto-part...nesize%3A_ANY_
Heres the Motive gears on Summit:
https://www.summitracing.com/parts/m...ette/year/2004
Great. Thanks for the information. One last question on the required parts. What Valve Seals would you recommend? In researching this I'm seeing both 1-piece and 2-piece based on the C5 year. Can the originals be used if I'm installing new LS6 valve springs?
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Heres a good video to help you get a picture in your minds eye of the spring/seal job.
The seals he’s using are an aftermarket OEM style. The LS6 springs in the video are no longer blue, just gray.
Melting Slicks
Joined: Dec 2004
Posts: 2,847
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From: Sleepy Hollow- NJ
Thanks forum for all the info, great thread - I've been considering a cam swap on my 01 vert with a manual and the 3:42 gears - would like to do the supercharger but I 'm not sure I want to get into a hood swap and all the other ancillary changes and the $$ involved just doesn't seem like something i could justify - with just the cam swap what else would you need to switch out? At what point does the added HP (thinking if I went with the supercharger) suggest getting a more robust tranny? Rear-end?
Thinking if I could get around 400 or so to the wheels I would be happy ( well at least happier) - I've got an Air-raid cold air, Corsa X pipe and tigershark tips but haven't had it dyno tuned after they were put in
Any and all suggestions welcome
Thinking if I could get around 400 or so to the wheels I would be happy ( well at least happier) - I've got an Air-raid cold air, Corsa X pipe and tigershark tips but haven't had it dyno tuned after they were put in
Any and all suggestions welcome
Depending on power levels, how you drive the car (street only) and tires used (street vs. DRs) an upgraded tranny and diff may never be needed. Especially going FI on otherwise stock motor/power.
I had 418whp (NA not FI) go for a very long time/tens of thousands of miles on stock MN6 trans and 3 rib diff. Street driving the car with a street tire.
Running same trans (140k miles later) with a z06 3 rib on FI 634whp/568rwtq and am now likely on borrowed time.
CAI and catback are negligible for HP gains. As are long tube headers on an otherwise stock motor. Most of the power you'll find after these mods will come from the tune itself not so much the additional parts.
Last edited by Johnny Hardcore; Feb 4, 2022 at 11:04 AM.
Melting Slicks
Joined: Dec 2004
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From: Sleepy Hollow- NJ
Some good points!
Still, he has an A4, so he needs to consider that a more aggressive cam may require a higher stall converter, another couple grand. In addition, a bigger cam will want headers, another couple grand….
I was approaching the OPs intentions from both budget and overall performance. With the additional expense mentioned, he would be in supercharger price ranges. Just depends on his budget and how far he wants to go.
Still, he has an A4, so he needs to consider that a more aggressive cam may require a higher stall converter, another couple grand. In addition, a bigger cam will want headers, another couple grand….
I was approaching the OPs intentions from both budget and overall performance. With the additional expense mentioned, he would be in supercharger price ranges. Just depends on his budget and how far he wants to go.
A new converter is about $1k from TX Speed as well as other suppliers. So it's not "thousands of dollars". It's one thousand dollars.
In full agreement that steeper gears are a must when going with a cam that makes power higher in the curve. More cam needs more gear.
Racer
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In Oct of 2021 I had new Cam install along with supporting mods and a couple of while its apart replacement parts I did not do headers was only looking for 390 to 400 HP my car is 6speed still on stock clutch will do headers when I do new clutch cars was dyno tune as part of package @ 406 @ 6200RPM cost was over 7k with tax Yes i know i could have gone with supercharger for not much more and more HP but truth be I love the sound of a cam car and not so much the whine of SC hope this helps
New o2 sensor
Custom cam ECS
spring kit titanium retainers, GM LS7 lifters and guides
Texas speed 2.5 5.3 heads
timing chain HV oil pump
push rods
most important new power bond harmonic balancer new belts and gaskets NGK sparkplugs and wires
New o2 sensor
Custom cam ECS
spring kit titanium retainers, GM LS7 lifters and guides
Texas speed 2.5 5.3 heads
timing chain HV oil pump
push rods
most important new power bond harmonic balancer new belts and gaskets NGK sparkplugs and wires
Le Mans Master
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In agreement with grinder on the cam specs. Doing a stock LS6 cam swap is likely going to be a big let down. At least based on years of feedback from those that have posted on the forum about making this mistake. The LS6 power max is a better option than the two LS6 OEM cams offered. Still I would go 224/224 or 228/228 at a minimum.
A new converter is about $1k from TX Speed as well as other suppliers. So it's not "thousands of dollars". It's one thousand dollars.
In full agreement that steeper gears are a must when going with a cam that makes power higher in the curve. More cam needs more gear.
A new converter is about $1k from TX Speed as well as other suppliers. So it's not "thousands of dollars". It's one thousand dollars.
In full agreement that steeper gears are a must when going with a cam that makes power higher in the curve. More cam needs more gear.
My comment is based on the OP stating he’ll be using his mechanic at $157/hour. That would add about another thousand.
Melting Slicks
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From: Sleepy Hollow- NJ
Race Director
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In Oct of 2021 I had new Cam install along with supporting mods and a couple of while its apart replacement parts I did not do headers was only looking for 390 to 400 HP my car is 6speed still on stock clutch will do headers when I do new clutch cars was dyno tune as part of package @ 406 @ 6200RPM cost was over 7k with tax Yes i know i could have gone with supercharger for not much more and more HP but truth be I love the sound of a cam car and not so much the whine of SC hope this helps
New o2 sensor
Custom cam ECS
spring kit titanium retainers, GM LS7 lifters and guides
Texas speed 2.5 5.3 heads
timing chain HV oil pump
push rods
most important new power bond harmonic balancer new belts and gaskets NGK sparkplugs and wires
New o2 sensor
Custom cam ECS
spring kit titanium retainers, GM LS7 lifters and guides
Texas speed 2.5 5.3 heads
timing chain HV oil pump
push rods
most important new power bond harmonic balancer new belts and gaskets NGK sparkplugs and wires
Melting Slicks
Joined: Dec 2004
Posts: 2,847
Likes: 1,144
From: Sleepy Hollow- NJ
In Oct of 2021 I had new Cam install along with supporting mods and a couple of while its apart replacement parts I did not do headers was only looking for 390 to 400 HP my car is 6speed still on stock clutch will do headers when I do new clutch cars was dyno tune as part of package @ 406 @ 6200RPM cost was over 7k with tax Yes i know i could have gone with supercharger for not much more and more HP but truth be I love the sound of a cam car and not so much the whine of SC hope this helps
New o2 sensor
Custom cam ECS
spring kit titanium retainers, GM LS7 lifters and guides
Texas speed 2.5 5.3 heads
timing chain HV oil pump
push rods
most important new power bond harmonic balancer new belts and gaskets NGK sparkplugs and wires
New o2 sensor
Custom cam ECS
spring kit titanium retainers, GM LS7 lifters and guides
Texas speed 2.5 5.3 heads
timing chain HV oil pump
push rods
most important new power bond harmonic balancer new belts and gaskets NGK sparkplugs and wires
You get the lope of a big cam, the slight whine of a centri charger, the awesome whoosh of a BOV and gobs of power.
Stock like driveability under 3000 RPM even with the bigger cam.
Racer
Joined: Jan 2003
Posts: 461
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From: Free state of Florida
Exactly what builder said I could do both, was not trying to build a high HP car just give mine a few more pony's, I do know enough that horse power always finds the weakest link. I fail to mention I have a convertible to really have fun I need a roll cage so I'd be chasing the rabbit hole besides breaking my own rule of spending on mods just to get HP of C6/C7 zo6 when i could just buy that
Melting Slicks
Joined: Dec 2004
Posts: 2,847
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From: Sleepy Hollow- NJ
Exactly what builder said I could do both, was not trying to build a high HP car just give mine a few more pony's, I do know enough that horse power always finds the weakest link. I fail to mention I have a convertible to really have fun I need a roll cage so I'd be chasing the rabbit hole besides breaking my own rule of spending on mods just to get HP of C6/C7 zo6 when i could just buy that
I won't part with my first C5. I've since purchased many cars including 2 more C5s. Which both came and went. When I get bored I make upgrades.
Yet I've still not ever found myself shopping C6's or C7's of any variant. They just don't do it for me on any level. I dabbled with buying a C8 after seeing them at Carlisle for the first time. Nixed that idea, supercharged the C5 and bought a $70k truck instead.