I am waiting to see if a "Cat-Back" Exhaust will become available. If one does not, I plan to have a custom 'Cat-Back' built with 2.5" mandrel-bent SS piping, a MagnaFlow Camaro-style SS muffler and 4" polished tips. I would also replace the resonator with a 'glasspack' muffler. ;)

Intake an exhaust for me, I really want to get that damn resonator replaced with something that has way more flow.

custom full 3" mandrel bend SS exhaust, apex'i muffler no cats, or resonator. And probably an RSM intake...and depends what else comes out.
jeff

If anything EVER comes out for the 3.9....I'm hoping for a CAI and a nice cat-back exhaust.

Mike

custom full 3" mandrel bend SS exhaust, apex'i muffler no cats, or resonator. And probably an RSM intake...and depends what else comes out.
jeff

Neither the 3.5 nor the 3.9 push enough air to justify a 3" exhaust.

Anything over 2.5" and you're going to kill the torque, which is one of the few things these engines have going for them.

Either a car, deer or telephone pole hood ornament. :D er... Weight reduction? ;)

I was thinking maybe SCGA1's avatar :D To me that would be the best upgrade of all...

Neither the 3.5 nor the 3.9 push enough air to justify a 3" exhaust.

Anything over 2.5" and you're going to kill the torque, which is one of the few things these engines have going for them.

on most engines 3" exhaust is the standard after exceeding 300HP. And due to the ratio, if you have about 300HP you should be clost to 400TQ given the ratio on these motors and what exactly you mod, so losing 15 TQ is fine by me for a tone and better flow.
jeff

True.. of course true duals can keep dual 2.5inch pipes and still be ok. :D

I was thinking maybe SCGA1's avatar :D To me that would be the best upgrade of all...I wish I could have her in my passenger seat, everywhere I go! :)

on most engines 3" exhaust is the standard after exceeding 300HP. And due to the ratio, if you have about 300HP you should be clost to 400TQ given the ratio on these motors and what exactly you mod, so losing 15 TQ is fine by me for a tone and better flow.
jeff

Hey, if you can get to 300HP in a G6 GT with just a new muffler and an RSM intake, then you've broken the laws of physics so pipe diameter will no longer matter. Heck, even RSM's SC kit will only get you to 280.

Ratio? You mean the HP/TQ ratio? It isn't going to be linear for very long when you start playing with things that are going to push a G6 over 300HP (which, by the way, will require the installation of a 4T65 'cuz the 4T45 ain't gonna take much more than about 250 without turning in its notice).

Hey, that reminds me...we should all send GM a big group THANKS for hamstringing modding efforts with this pitiful tranny.

Hey, that reminds me...we should all send GM a big group THANKS for hamstringing modding efforts with this pitiful tranny.
I don't get how it's GM's fault they put in a tranny rated to handle only what the stock engine puts out? I mean, the exhaust isn't loud enough, so we change it. The intake isn't good enough, so we change it. Why should the tranny be any different?
Has anyone even tested what this tranny can actually handle? There's a guy here in town that has an 04 Impala that ran 12's on the stock tranny.

Hey, if you can get to 300HP in a G6 GT with just a new muffler and an RSM intake, then you've broken the laws of physics so pipe diameter will no longer matter. Heck, even RSM's SC kit will only get you to 280.

Ratio? You mean the HP/TQ ratio? It isn't going to be linear for very long when you start playing with things that are going to push a G6 over 300HP (which, by the way, will require the installation of a 4T65 'cuz the 4T45 ain't gonna take much more than about 250 without turning in its notice).

Hey, that reminds me...we should all send GM a big group THANKS for hamstringing modding efforts with this pitiful tranny.

im not saying those mods alone will bring me to that level at all, because like you said its breaking the laws of physics, but getting it accomplished before I bring it to that point would be a +
and what does the 4T65 come out of?
jeff

and what does the 4T65 come out of?
jeff
It's mostly on the supercharged 3800's (Grand Prix, Impala, Monte Carlo, and Regal). I think the CTS uses it too?

well i would be more happy removing the tranny and having it strengthened by professionals. Than wasting all my time in seeing if this tranny would bolt up to our motor, custom housings and such, blah screw that. And I dont see why this tranny necessarily would go out at 250 when according to the fact sheets its at roughly 200HP now, makes no sense.
jeff

EDIT. I see the 4T45-E is

Type: four speed front-wheel-drive, electronically
controlled, automatic overdrive transaxle
with electronically controlled torque converter
clutch
Engine range: 3.0L - 3.4L
Maximum engine torque: 205 lb-ft (278 Nm)
Maximum gearbox torque: 325 lb-ft (440 Nm)
Gear ratios:
First: 2.95
Second: 1.62
Third: 1.00
Fourth: 0.68
Reverse: 2.14
Maximum shift speed: 5800 rpm
Maximum validated gross vehicle weight: 1990 kg (4347 lb)
7-position quadrant: P, R, N, OD, 3, 2, 1
5-position quadrant: P, R, N, D, D3 (Malibu)
Case material: die cast aluminum
Shift pattern: (2) two-way on/off solenoids
Shift quality: variable bleed solenoid
Torque converter clutch: pulse width modulated solenoid control
Converter size: 245mm (reference) (diameter of torque
converter turbine)
Fluid type: DEXRON VI
dry: 74.7 kg (164 lb)
wet: 85.1 kg (187.6 lb)
Fluid capacity (approximate): bottom pan removal: 7L (7.4 qt)
Complete overhaul: 10L (10.6 qt)
dry: 12.5L (13.2 qt)
Pressure taps available: line pressure
Transfer design: two-axis design, link chain assembly
Assembly sites: Windsor, Ontario
Chevrolet Cobalt
Pontiac Pursuit
Chevrolet Malibu & Malibu Maxx
Pontiac Grand Am
Pontiac G6
Saturn Ion
Saturn Vue
Chevrolet HHR


and the 4T65-E which is in the 3.9 G6

2006 Hydra-Matic 4T65-E Transaxle
(M15/MD7/MN7/M76)
Type: four speed front-wheel-drive, electronically
controlled, automatic overdrive transaxle
with electronically controlled torque
converter clutch.
Engine range: 2.5L - 5.3L
Maximum engine torque: 280 lb-ft (380 Nm)
Maximum gearbox torque: 400 lb-ft (542 Nm)
Gear ratios:
First: 2.92
Second: 1.56
Third: 1
Fourth: 0.7
Reverse: 2.38
1-2 7000 rpm
2-3 6500 rpm
3-4 6000 rpm
Maximum validated gross vehicle weight: 2903 kg (6400 lb)
7-position quadrant: P, R, N, OD, 3, 2, 1
5-position quadrant: P, R, N, D & DSC +/-
Case material: die cast aluminum
Shift pattern: (2) two-way on/off solenoids
Shift quality: variable bleed solenoid
Torque converter clutch: pulse width modulated solenoid control
Converter size: 245mm and 258mm (reference) (diameter of
torque converter turbine)
DEXRON IV
BOT190M1 - all wheel drive fluid for power
take off unit
93 kg (205 lb) (M15) (wet)
96.6 kg (212 lb) (MN3) (wet)
97.2 kg (214 lb) (MN7) (wet)
112.5 kg (248 lb) (M76 with power take off
(PTO) Unit) (wet)
Fluid capacity (approximate): bottom pan removal: 7L (7.4 qt)
9.5L (10 qt)
12.7L (13.4 qt) (dry)
13.1L (13.8 qt) (M76) (dry)
Pressure taps available: line pressure
Transfer design: two-axis design, link chain assembly
M15: 245/258mm torque converter
MD7 - 245mm China Applications
MN7: 258mm torque converter and heavyduty
gearbox
M76: 245/258mm torque converter & (AWD)
Assembly sites: Warren, Mich. (M15, MN7, M76)
Shanghai, China (MD7)
Chevrolet Malibu (M15)
Chevrolet Malibu Maxx (M15)
Chevrolet Impala (M15)
Chevrolet Monte Carlo (M15)
Chevrolet Uplander (M15, M76)
Buick LaCrosse (M15)
Buick Lucerne (M15)
Buick Terraza (M15, M76)
Buick Rendezvous (M15, M76)
Pontiac Grand Prix (M15, MN7)
Pontiac Montana (M15, M76)
Saturn Relay (M15, M76)

and heres your standard 6speed numbers too

2006 F40 (MT2)
Type: transverse front wheel drive, six
speed manual transaxle
Engine range: 3.9L
Maximum engine torque: 245 lb-ft ( 333 Nm )
Maximum gearbox torque: 295 lb-ft ( 400 Nm )
Gear ratios: MT2
First: 3.77
Second: 2.04
Third: 1.32
Fourth: 0.95
Fifth: 0.76
Sixth: 0.62
Reverse: 3.54
Final Drive 3.55
Maximum validated gross vehicle weight: 3527 lb ( 1600 kg )
Case material: aluminum
Center distance: 197 mm
Fluid type: Castrol BOT 0063
Transmission weight: 56 kg ( 123.5 lb )
Fluid capacity (approximate): 3.1L / 3.27 qt ( dry )
Power take off: no
Applications: Pontiac G6

now you tell me if there is something wrong with these rated numbers.
jeff

If you had the money and were serious...

FWD LS1 Conversion ;) You could skip right over blowing money on the 3.5/3.9L and get serious. :)

GM Rates all their trannys low for liability reasons. I dipped into mid 14's with my GA and never had any issues with the tranny. At the time that those specs where drafted 205f/lbs was probably the most being pumped into a 4T45 by any GM vehicle.

GM Rates all their trannys low for liability reasons. I dipped into mid 14's with my GA and never had any issues with the tranny. At the time that those specs where drafted 205f/lbs was probably the most being pumped into a 4T45 by any GM vehicle.

hmm well i dont want to do too much to my car, I just want intake, exhaust, PCM upgrade (when available) some springs and SC(and of course all incorporated performance parts to allow such a mod). The supercharger is going to bring the most power out of all these projected mods of course. I just hope it does not bring my cars tranny to a halt. I dont drive this car hard rarely, due to my payments haha.

hmm well i dont want to do too much to my car, I just want intake, exhaust, PCM upgrade (when available) some springs and SC(and of course all incorporated performance parts to allow such a mod). The supercharger is going to bring the most power out of all these projected mods of course. I just hope it does not bring my cars tranny to a halt. I dont drive this car hard rarely, due to my payments haha.
Supercharged GA start running into problems around 22oWHP, but switching to a full synthetic and installing a larger cooler will prolong is life, and its all how you drive it to.

whats a GA? im not used to domestic engine codes, I thought ours was a LX9(engine)? for 3.5 anyways.
jeff

GA= Grand Am ;)

I don't get how it's GM's fault they put in a tranny rated to handle only what the stock engine puts out? I mean, the exhaust isn't loud enough, so we change it. The intake isn't good enough, so we change it. Why should the tranny be any different?
Has anyone even tested what this tranny can actually handle? There's a guy here in town that has an 04 Impala that ran 12's on the stock tranny.

How is it their fault? Same way it's their fault that THEY put in a quiet exhaust and a "blah" intake. Because THEY built it...that's how it's their fault. It was probably good business sense in that it was likely less expensive the the 65, but lacked proper forethought on their part.

The Impala has the 4T65. That's why he doesn't have any problems running 12's on it. The 4T65 is essentially a strengthened 4-speed variant of the venerable TH350 - dang near bulletproof.

GM Rates all their trannys low for liability reasons. I dipped into mid 14's with my GA and never had any issues with the tranny. At the time that those specs where drafted 205f/lbs was probably the most being pumped into a 4T45 by any GM vehicle.

Exactly why I threw out 250. That's giving them a generous 25% allowance for liability.

Do the same for the 4T65 and you're looking at around 350lbs. Pretty healthy.

The 205 is the new higher rating to accomodate the G6. Prior to that, it was slightly below 200 because the 45 was relegated to the Malibu, GA, and other related mid-size models - all sub-200.

Nonetheless, spoolin has the right idea. Both trannys can be strengthened considerably and for less expense than buying a new one - and should seriously be considered prior to installing forced induction.

Near the end of 2006 I will be getting the best performance boost out there: dumping the G6 and getting a GTO (hopefully!).

Near the end of 2006 I will be getting the best performance boost out there: dumping the G6 and getting a GTO (hopefully!).

Sounds like an easy way to boost the HP and torque considerably!

I believe the actual rating numbers are Power over time ratings...

For instance... a 4L60E stock has been known to handle 500lb trq for a short time...but its rated at 360ft lbs. Another words... even though a tranny says it will hold only 200HP I believe their intentions were 200hp for 100,000 miles. (or 75K..something to that effect..) The transmission WILL hold more power than that for a lesser amount of time.

I believe the actual rating numbers are Power over time ratings...

For instance... a 4L60E stock has been known to handle 500lb trq for a short time...but its rated at 360ft lbs. Another words... even though a tranny says it will hold only 200HP I believe their intentions were 200hp for 100,000 miles. (or 75K..something to that effect..) The transmission WILL hold more power than that for a lesser amount of time.

I wouldn't doubt it for a minute. My old Cheviac Grand Chevelle SS started out as a boring GrandPrix with a TH250 mated to a 301. When I swapped in the 350 out of my Chevelle (see where the name comes from?), I left the 250 in just to see what happened. It lasted for almost 100 miles before it lost 2nd gear entirely.

Not an experiment I'm willing to try again on the G6, since the stock 4T45 isn't much better than a TH250.

I wouldn't doubt it for a minute. My old Cheviac Grand Chevelle SS started out as a boring GrandPrix with a TH250 mated to a 301. When I swapped in the 350 out of my Chevelle (see where the name comes from?), I left the 250 in just to see what happened. It lasted for almost 100 miles before it lost 2nd gear entirely.

Not an experiment I'm willing to try again on the G6, since the stock 4T45 isn't much better than a TH250.

comparing those two trannys in relative HP is not accurate. technology and alloys being used in the 4T45E are different than what they used to be.
jeff

I'm currently working with 2 companies right now for some performance products for the 3.9L...however I don't wanna jinx anything ;)

comparing those two trannys in relative HP is not accurate. technology and alloys being used in the 4T45E are different than what they used to be.
jeff

Yeah, the fourth gear, the lockup converter, and the electronic sender in place of the old worm gear speedo drive certainly makes the 45 a MUCH hardier tranny that the 250.

Yeah, maybe some of the internal parts are of a different metal than good old-fashioned case hardened steel, but I'll guarantee you that the engine that gutted that TH250 would ream a new hole right in a stock 4T45's butt.

At any rate, you missed the point of the post. Read it again from the perspective presented by the quote from S8ER99 - it's to give him props with an experience from real-life that illustrates his statement. (If I had nursed it along, the 250 would have lasted just fine...)

yea my mistake, im finishing up a 12 hour shift...hiding from boss haha. sorry if im incoherent.
jeff