Special thanks to all members who contributed to the original thread on this subject

Quaife 6-Speed Conversion for FGP F35 5-Speed Manual Transmission!

Quaife has recently announced the availability of a 6-speed conversion kit for the 2005+ Cobalt SS Supercharged, ION Redline, and SAAB 9-3 equipped with the 5-Speed GM F35 Transmission!

This post is designed to supply you with as much information regarding said conversion as possible, and will be updated as information changes or becomes available.

Currently available to you in this thread are the following:

• Gear Ratios for both transmissions
• Text Readouts from Quaife's own QSpeedCalc, a program that calculates your vehicle's speed, rev drops, etc. when gear ratios, tire sizes, and engine speed are input.
• Graphs generated by QSpeedCalc

If anyone actually performs this conversion and is graceful enough to make a how-to during the procedure, a link to that persons thread will be added here. (Although I'm not so sure many people will be tearing apart their own transmissions for this... I think. )

Quote from Quaife Site:

Now, on to the specifics:

Cost:
GM F35 6-speed synchromesh, Cobalt SS SC, Ion Redline - $4,195.00 - Link (Price updated 05-20-2007)

Gear Ratios:

5-Speed FGP F35 Transmission:

Type: Transverse front wheel drive, five-speed manual transaxle ( Optional with limited slip differential )
Engine range: 2.0L I-4 supercharged
Maximum engine torque: 200 lb-ft ( 271 Nm)
Maximum gearbox torque: 258 lb-ft ( 350 Nm )
Wheel+Tire Circumference: 2044mm
Gear ratios: MU3

• First: 3.38
• Second: 1.76
• Third: 1.18
• Fourth: 0.89
• Fifth: 0.7
• Reverse: 3.17
• Final Drive Ratio: 4.04

Maximum validated gross vehicle weight 2300 kg
Case material: aluminum
Center distance: 76.5mm
Fluid type: Castrol BOT 0063
Transmission weight: wet: 45 kg ( 99 lb )
Fluid capacity (approximate): 1.7L / 2.0 qt. ( dry )
Power take off: no
Applications: Chevrolet Cobalt SS Supercharged, Saturn ION Redline, Saab 9-3 Turbo

5-Speed FGP F35 Transmission using Quaife's 6-Speed conversion:

Type: Transverse front wheel drive, five-speed manual transaxle ( Optional with limited slip differential )
Engine range: 2.0L I-4 supercharged
Maximum engine torque: 200 lb-ft ( 271 Nm)
Maximum gearbox torque: 258 lb-ft ( 350 Nm )
Wheel+Tire Circumference: 2044mm
Gear ratios: MU3

• First: 2.72
• Second: 1.89
• Third: 1.368
• Fourth: 1.045
• Fifth: 0.833
• Sixth: 0.704
• Reverse: 3.17
• Final Drive Ratio: 4.04

Maximum validated gross vehicle weight 2300 kg
Case material: aluminum
Center distance: 76.5mm
Fluid type: Castrol BOT 0063
Transmission weight: wet: 45 kg ( 99 lb )
Fluid capacity (approximate): 1.7L / 2.0 qt. ( dry )
Power take off: no
Applications: Chevrolet Cobalt SS Supercharged, Saturn ION Redline, Saab 9-3 Turbo

QSpeedCalc

The following section was generated using QSpeedCalc, with the above gear ratios and wheel diameters as input.
Three sets of readouts and graphs were created per transmission, one per each commonly used redline:

• 6450(stock)
• 7000(GMPP Stage 2)
• 7200(attainable through aftermarket tuning and generally agreed upon as "safe")

Text Readouts:

5-Speed @ 6450rpm:

Gearbox:- 5-Speed Cobalt SS Supercharged @ 6450rpm
Tyre:- Pirelli Pzero Rosso Asymmetrico 215/45/18
-------------------------------------------------------------------------------------------
Top Gear gives 26.947 MPH/1000 RPM and a top speed of 173.806 MPH at 6450 RPM

Engine speeds in top gear:-
30 MPH = 1113 RPM 40 MPH = 1484 RPM 50 MPH = 1856 RPM 60 MPH = 2227 RPM
70 MPH = 2598 RPM 80 MPH = 2969 RPM 90 MPH = 3340 RPM 100 MPH = 3711 RPM

Top Speed in 1 gear = 35.995 MPH
And changes into 2 gear at 3359 RPM dropping 3091 RPM
Top Speed in 2 gear = 69.127 MPH
And changes into 3 gear at 4324 RPM dropping 2126 RPM
Top Speed in 3 gear = 103.105 MPH
And changes into 4 gear at 4865 RPM dropping 1585 RPM
Top Speed in 4 gear = 136.701 MPH
And changes into 5 gear at 5073 RPM dropping 1377 RPM
Top Speed in 5 gear = 173.806 MPH
************************************************** ****************************************
5-Speed @ 7000rpm:

Gearbox:- 5-Speed Cobalt SS Supercharged @ 7000rpm
Tyre:- Pirelli Pzero Rosso Asymmetrico 215/45/18
-------------------------------------------------------------------------------------------
Top Gear gives 26.947 MPH/1000 RPM and a top speed of 188.626 MPH at 7000 RPM

Engine speeds in top gear:-
30 MPH = 1113 RPM 40 MPH = 1484 RPM 50 MPH = 1856 RPM 60 MPH = 2227 RPM
70 MPH = 2598 RPM 80 MPH = 2969 RPM 90 MPH = 3340 RPM 100 MPH = 3711 RPM

Top Speed in 1 gear = 39.065 MPH
And changes into 2 gear at 3707 RPM dropping 3293 RPM
Top Speed in 2 gear = 73.764 MPH
And changes into 3 gear at 4615 RPM dropping 2385 RPM
Top Speed in 3 gear = 111.897 MPH
And changes into 4 gear at 5280 RPM dropping 1720 RPM
Top Speed in 4 gear = 148.358 MPH
And changes into 5 gear at 5506 RPM dropping 1494 RPM
Top Speed in 5 gear = 188.626 MPH
************************************************** ****************************************
5-Speed @ 7200rpm:

Gearbox:- 5-Speed Cobalt SS Supercharged @ 7200rpm
Tyre:- Pirelli Pzero Rosso Asymmetrico 215/45/18
-------------------------------------------------------------------------------------------
Top Gear gives 26.947 MPH/1000 RPM and a top speed of 194.015 MPH at 7200 RPM

Engine speeds in top gear:-
30 MPH = 1113 RPM 40 MPH = 1484 RPM 50 MPH = 1856 RPM 60 MPH = 2227 RPM
70 MPH = 2598 RPM 80 MPH = 2969 RPM 90 MPH = 3340 RPM 100 MPH = 3711 RPM

Top Speed in 1 gear = 40.181 MPH
And changes into 2 gear at 3749 RPM dropping 3451 RPM
Top Speed in 2 gear = 77.165 MPH
And changes into 3 gear at 4827 RPM dropping 2373 RPM
Top Speed in 3 gear = 115.094 MPH
And changes into 4 gear at 5431 RPM dropping 1769 RPM
Top Speed in 4 gear = 152.596 MPH
And changes into 5 gear at 5663 RPM dropping 1537 RPM
Top Speed in 5 gear = 194.015 MPH
************************************************** ****************************************
6-Speed @ 6450rpm:
Gearbox:- 6-Speed Cobalt SS Supercharged @ 6450rpm
Tyre:- Pirelli Pzero Rosso Asymmetrico 215/45/18
-------------------------------------------------------------------------------------------
Top Gear gives 26.793 MPH/1000 RPM and a top speed of 172.818 MPH at 6450 RPM

Engine speeds in top gear:-
30 MPH = 1120 RPM 40 MPH = 1493 RPM 50 MPH = 1866 RPM 60 MPH = 2239 RPM
70 MPH = 2613 RPM 80 MPH = 2986 RPM 90 MPH = 3359 RPM 100 MPH = 3732 RPM

Top Speed in 1 gear = 44.729 MPH
And changes into 2 gear at 4482 RPM dropping 1968 RPM
Top Speed in 2 gear = 64.372 MPH
And changes into 3 gear at 4669 RPM dropping 1781 RPM
Top Speed in 3 gear = 88.936 MPH
And changes into 4 gear at 4927 RPM dropping 1523 RPM
Top Speed in 4 gear = 116.425 MPH
And changes into 5 gear at 5141 RPM dropping 1309 RPM
Top Speed in 5 gear = 146.055 MPH
And changes into 6 gear at 5451 RPM dropping 999 RPM
Top Speed in 6 gear = 172.818 MPH
************************************************** ****************************************
6-Speed @ 7000rpm:
Gearbox:- 6-Speed Cobalt SS Supercharged @ 7000rpm
Tyre:- Pirelli Pzero Rosso Asymmetrico 215/45/18
-------------------------------------------------------------------------------------------
Top Gear gives 26.793 MPH/1000 RPM and a top speed of 187.554 MPH at 7000 RPM

Engine speeds in top gear:-
30 MPH = 1120 RPM 40 MPH = 1493 RPM 50 MPH = 1866 RPM 60 MPH = 2239 RPM
70 MPH = 2613 RPM 80 MPH = 2986 RPM 90 MPH = 3359 RPM 100 MPH = 3732 RPM

Top Speed in 1 gear = 48.543 MPH
And changes into 2 gear at 4864 RPM dropping 2136 RPM
Top Speed in 2 gear = 69.862 MPH
And changes into 3 gear at 5067 RPM dropping 1933 RPM
Top Speed in 3 gear = 96.519 MPH
And changes into 4 gear at 5347 RPM dropping 1653 RPM
Top Speed in 4 gear = 126.352 MPH
And changes into 5 gear at 5580 RPM dropping 1420 RPM
Top Speed in 5 gear = 158.509 MPH
And changes into 6 gear at 5916 RPM dropping 1084 RPM
Top Speed in 6 gear = 187.554 MPH
************************************************** ****************************************
6-Speed @ 7200rpm:
Gearbox:- 6-Speed Cobalt SS Supercharged @ 7200rpm
Tyre:- Pirelli Pzero Rosso Asymmetrico 215/45/18
-------------------------------------------------------------------------------------------
Top Gear gives 26.793 MPH/1000 RPM and a top speed of 192.913 MPH at 7200 RPM

Engine speeds in top gear:-
30 MPH = 1120 RPM 40 MPH = 1493 RPM 50 MPH = 1866 RPM 60 MPH = 2239 RPM
70 MPH = 2613 RPM 80 MPH = 2986 RPM 90 MPH = 3359 RPM 100 MPH = 3732 RPM

Top Speed in 1 gear = 49.930 MPH
And changes into 2 gear at 5003 RPM dropping 2197 RPM
Top Speed in 2 gear = 71.858 MPH
And changes into 3 gear at 5211 RPM dropping 1989 RPM
Top Speed in 3 gear = 99.277 MPH
And changes into 4 gear at 5500 RPM dropping 1700 RPM
Top Speed in 4 gear = 129.963 MPH
And changes into 5 gear at 5739 RPM dropping 1461 RPM
Top Speed in 5 gear = 163.038 MPH
And changes into 6 gear at 6085 RPM dropping 1115 RPM
Top Speed in 6 gear = 192.913 MPH
************************************************** ****************************************
Graphs:

5-Speed @ 6450rpm, 7000rpm, & 7200rpm:

5-Speed Comparison:


6-Speed @ 6450rpm, 7000rpm, & 7200rpm:

6-Speed Comparison:

 

Thanks Pyro for taking the time to complie all of that data together for us.

 

Is it really worth it? Doesnt seem to go any faster but I guess it will help you get up there alot faster

 

Are there new torque capacity ratings?

 

I'm liking that first gear ratio. ALOT.

 

Just a little note, the 5-speed comparison graph is the same as the 6-speed one. WHOOPS. I'll fix when I get home.

As far as torque capacity and things like that, I'll do my best to research what I can, but any additional information would be greatly appreciated.

 

Now they have removed the pricing from their site?!?

http://www.autotech.com/quaife/index2.htm

 

Its still there. Youre half right though.

This page has the price listed: http://www.autotech.com/quaife/gears/gears.htm
This one says to call them: http://www.autotech.com/quaife/gears/GMF35.htm

 

They changed it again. The gears page did not have a price when I posted the link, it does now. Regardless, still no capacity numbers there.

 

Why don't you put a graph together comparing the 5 speed to 6 speed at 7000 rpm shift points. That should give you an idea on how the car will pull different between the gears.

 

price GONE!

 

Wow...

1st gear alone is enough reason for me to swap

 

this would be the ultimate mod...... this would be a more important swap than the twin screw It seems that 1st gear is lengthened ( stock is too close, IMO ) so it helps with traction and launches, 2nd gear is closer for quicker acceleration, if this is all that this coversion changed it would still be worth doing, not sure about the ridiculous price though..

 

I want this kit! I love my 6spd Z28, and I would love to have my SS/SC converted to a 6spd!

 

price seems a little steep. Am I reading correctly that this is jsut for the gears? so you have to also install everything or have someone do it? and the lsd isn't included in that price?

 

I wonder if GM will warrenty this since they are contracted with Quaife and this a Quaife product designed specific to their car?. And I pray the Torque Capacity is higher. Brandon if your gunna pay $4,000 for the 6 speed gearing then why not go the extra $900 for a LSD?

 

you missed my point, paying 4k for just the gears without the lsd is really expensive for not much improvement.

gm wouldn't warranty that because it doesn't come stock.

 

now there my friend you are very wrong......they warranty corsa exhausts...and they arent stock.....not sure though....a 6spd conversion would allow more top end and power capabilities if im right....so it could go both ways if you look at it....depends on if gmis looking to support the aftermarket or not.....id say probably not simply because of more top end allowing the car to go faster then its aerodynamically designed to handle....

 

Like a said b4 and ill say again it would be an interesting mod that i would like to do in conjunciton with LSD but that would be a bit down the line depending on how i feel putting over $10,000 into this since my dad is thinking about the Camaro Hardtop Convertible after he pays off the coby (I cant wait). And b4 any1 says anything i would be paying for the mods on this car myself not my dad.

 

I asked GM if they would warranty a stock transmission that had a Quaife LSD installed, by GM technicians. The answe, NO. They won't be warranting this upgrade either.

 

i would go for this if i could pick the gear ratios for this, but since they have allready set them it doesn't seem worth it.

 

the only problem with this is the price; its an expensive part to buy and i dont see it being cheap to install.

it would be an awesome mod if someone could figure out how to do it cheaper.

 

comon ..comparing a cat back to a tranny?

 

so if you bought a corsa exhasut and it rusted trhough...GM would replace it? Now if it was factory installed and DELIVERED as part of the car from the factory, then it could go udner the original factory warranty. As far as i know, you can't get a corsa exhaust from the factory. Regardless of that, you can not get a 6spd cobalt ss/sc from the factory, there.. so it would not be covered under the factory warranty. Please, call you dealership and ask them(ignore the chuckles in the backround from the other employees) if the will cover your tranny if you installed a 6spd gear set into your ss/sc.

 

I just want the first gear and the LSD. I wonder how much they would charge just for the first gear and the appropriate synchros.