4.08 Final Drive on HR : any laptime improvment ?
03-31-2014, 10:52 AM
#1
Registered User
Thread Starter
4.08 Final Drive on HR : any laptime improvment ?
Hi,
I have an HR which is tuned for the track.
Here is the list of my mods :
AP racing 6 pots BBK 362mm-Pagid RS 29 brakes pads-
BC Racing RS Coilovers-Cusco Arms-Recaro Pole position seats-Stillen oil cooler kit 19 rows-GReedy trust oil pan-Kinetix HFC-Stillen dual High flow intakes-Injen SES1987TT exhaust with custom H Pipe- Rota P45 19 inch-Yokohama AD08 255/35 19 front 275/35 19 rear-4.08 Final drive-JWT 6 kg Flywheel-JWT Clutch-ZSpeed HD CSC-Wilwood HD clutch mastercylinder-DM Performance ECU Reflash (340 hp-391Nm)
I've just installed a 4.08 Final Gear.
I've done some acceleration test and i'm quite disapointed by the results.
A 38-100 mph (60-160 km/h) takes exactly the same time than stock FD.
A 50-100 mph (80-160 km/h) is a little slower than stock FD (1-2 tenth).
Ok i need to change gear more often, that's why i loose the benefit of the faster acceleration... But for just the impression you feel the car is faster but it isn't at all...
On the road though, on twisty roads, the car feels much faster between corners. The car is never between 2 gears like it is sometimes with the stock FD. The driving pleasure is a lot better.
But the main utilisation will be the track. I start with Bugatti Le Mans the 21/04...
So for you guys who are tracking your car and have the HR (on DE?) did you saw an improvment in your laptimes with this 4.08 Final Drive ?
Please tell me yes, because although the driving pleasure is better, the main reason i bought theses gears are to improve my laptimes with better corner exits and elasticity...
I have an HR which is tuned for the track.
Here is the list of my mods :
AP racing 6 pots BBK 362mm-Pagid RS 29 brakes pads-
BC Racing RS Coilovers-Cusco Arms-Recaro Pole position seats-Stillen oil cooler kit 19 rows-GReedy trust oil pan-Kinetix HFC-Stillen dual High flow intakes-Injen SES1987TT exhaust with custom H Pipe- Rota P45 19 inch-Yokohama AD08 255/35 19 front 275/35 19 rear-4.08 Final drive-JWT 6 kg Flywheel-JWT Clutch-ZSpeed HD CSC-Wilwood HD clutch mastercylinder-DM Performance ECU Reflash (340 hp-391Nm)
I've just installed a 4.08 Final Gear.
I've done some acceleration test and i'm quite disapointed by the results.
A 38-100 mph (60-160 km/h) takes exactly the same time than stock FD.
A 50-100 mph (80-160 km/h) is a little slower than stock FD (1-2 tenth).
Ok i need to change gear more often, that's why i loose the benefit of the faster acceleration... But for just the impression you feel the car is faster but it isn't at all...
On the road though, on twisty roads, the car feels much faster between corners. The car is never between 2 gears like it is sometimes with the stock FD. The driving pleasure is a lot better.
But the main utilisation will be the track. I start with Bugatti Le Mans the 21/04...
So for you guys who are tracking your car and have the HR (on DE?) did you saw an improvment in your laptimes with this 4.08 Final Drive ?
Please tell me yes, because although the driving pleasure is better, the main reason i bought theses gears are to improve my laptimes with better corner exits and elasticity...
03-31-2014, 11:08 AM
#2
Registered User
In total I spent over $1000 for everything when I swapped mine. I sure hope that it betters track time and that I didnt waste my money. It sure feels a lot faster to me. I raced a g35 stock and won him by almost a car length and about a week ago I raced an 06 and pulled on him by a car and a half with my mods being 4.08 and injen cai. Could be that the g35 driver was better.
03-31-2014, 11:18 AM
#3
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Not a track guy....but would say that depends on the track/course layout. A smaller/slower course would make the 4.08 shine by it keeping you with a higher rpm and speed through turns?
As you mentioned there is little gain in acceleration but the gains is there! Hype and buttdynos make 4.08s sounds like it's the must have mod! Other members have done similar straight line test and the result are the same...
In short the gears changed the cars rpm/shift pattern up to the driver to take advantage of it!
As you mentioned there is little gain in acceleration but the gains is there! Hype and buttdynos make 4.08s sounds like it's the must have mod! Other members have done similar straight line test and the result are the same...
In short the gears changed the cars rpm/shift pattern up to the driver to take advantage of it!
03-31-2014, 11:29 AM
#4
Registered User
yes higher gears probably just makes it feel faster but it actually isn't. If this is true I might switch back to stock gearing especially since bmurray just went on the dyno and it shows about a 5% loss in whp.
03-31-2014, 11:39 AM
#5
Registered User
I cant tell you how they are in road course type racing since I only drag race but I'm mainly commenting on what you said about acceleration being the same if not slightly slower with the 4.08 gear, I too have found that to be true in a way.
I have acceleration videos to show that as well. Since I broke my 4.08 gear set I've been back to the stock 3.5 FD and actually really like it, acceleration from "a roll" is better in my opinion, especially one you get in the higher gears such as 3rd and 4th.
I still need to hit the drag strip with the stock FD to see how the two differ in terms of E.T and Trap speed.
Again I wouldn't know when it comes to road course but just like King said, I can imagine 4.08 gears really shining in smaller, more technical tracks or in autocross events.
I have acceleration videos to show that as well. Since I broke my 4.08 gear set I've been back to the stock 3.5 FD and actually really like it, acceleration from "a roll" is better in my opinion, especially one you get in the higher gears such as 3rd and 4th.
I still need to hit the drag strip with the stock FD to see how the two differ in terms of E.T and Trap speed.
Again I wouldn't know when it comes to road course but just like King said, I can imagine 4.08 gears really shining in smaller, more technical tracks or in autocross events.
03-31-2014, 11:50 AM
#6
Registered User
I cant tell you how they are in road course type racing since I only drag race but I'm mainly commenting on what you said about acceleration being the same if not slightly slower with the 4.08 gear, I too have found that to be true in a way.
I have acceleration videos to show that as well. Since I broke my 4.08 gear set I've been back to the stock 3.5 FD and actually really like it, acceleration from "a roll" is better in my opinion, especially one you get in the higher gears such as 3rd and 4th.
I still need to hit the drag strip with the stock FD to see how the two differ in terms of E.T and Trap speed.
Again I wouldn't know when it comes to road course but just like King said, I can imagine 4.08 gears really shining in smaller, more technical tracks or in autocross events.
I have acceleration videos to show that as well. Since I broke my 4.08 gear set I've been back to the stock 3.5 FD and actually really like it, acceleration from "a roll" is better in my opinion, especially one you get in the higher gears such as 3rd and 4th.
I still need to hit the drag strip with the stock FD to see how the two differ in terms of E.T and Trap speed.
Again I wouldn't know when it comes to road course but just like King said, I can imagine 4.08 gears really shining in smaller, more technical tracks or in autocross events.
Wouldn't the 4.08 be better in a roll race though. I mean since you start in a higher rpm already in your power band.
03-31-2014, 12:01 PM
#7
Registered User
I wish I could show you the videos but I decided to delete my Google+ account the other day since I never used it, turns out it took my Youtube channel with it 
trying to recover it as we speak.
I feel that the stock FD is especially good in a roll race, taking advantage of the HRs top end power especially now with the PPEs I feel the motor is in a sweet spot anywhere above 5.5K rpm lol.
trying to recover it as we speak.I feel that the stock FD is especially good in a roll race, taking advantage of the HRs top end power especially now with the PPEs I feel the motor is in a sweet spot anywhere above 5.5K rpm lol.
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03-31-2014, 12:40 PM
#8
Registered User
I wish I could show you the videos but I decided to delete my Google+ account the other day since I never used it, turns out it took my Youtube channel with it trying to recover it as we speak.
I feel that the stock FD is especially good in a roll race, taking advantage of the HRs top end power especially now with the PPEs I feel the motor is in a sweet spot anywhere above 5.5K rpm lol.
trying to recover it as we speak.I feel that the stock FD is especially good in a roll race, taking advantage of the HRs top end power especially now with the PPEs I feel the motor is in a sweet spot anywhere above 5.5K rpm lol.
lol yea plus with the gears it shows a loss on the dyno. No one can really explain this. I think am going to switch back to stock FD but man I wasted a lot of cash.
03-31-2014, 01:03 PM
#9
Registered User
03-31-2014, 02:05 PM
#12
Registered User
Thats what I was thinking too but more and more people are saying that stock is better. Just wondering did you see a loss on the dyno when you did your gears?
Last edited by The_Assassin; 03-31-2014 at 02:07 PM.
03-31-2014, 02:31 PM
#13
New Member
iTrader: (4)
*by the way I'm very glad to have the 3.9 fd over the stock 3.5; love it!
Last edited by BigBlue; 03-31-2014 at 09:04 PM.
03-31-2014, 04:51 PM
#14
There is a 3.3, 3.5, 3.7, 3.9 and 4.08 FD.
I enjoy the 4.08 gearing! I did not notice a loss in WHP on the dyno. On the drag strip I did notice a loss in the 1/4 due to less traction with street tires and the extra shift I had to make.
On the track, at Watkins Glen the car seems to be in the powerband more often. It really depends on the track your on.
I enjoy the 4.08 gearing! I did not notice a loss in WHP on the dyno. On the drag strip I did notice a loss in the 1/4 due to less traction with street tires and the extra shift I had to make.
On the track, at Watkins Glen the car seems to be in the powerband more often. It really depends on the track your on.
Last edited by Lakeside; 03-31-2014 at 04:52 PM.
03-31-2014, 05:27 PM
#16
Registered User
There is a 3.3, 3.5, 3.7, 3.9 and 4.08 FD.
I enjoy the 4.08 gearing! I did not notice a loss in WHP on the dyno. On the drag strip I did notice a loss in the 1/4 due to less traction with street tires and the extra shift I had to make.
On the track, at Watkins Glen the car seems to be in the powerband more often. It really depends on the track your on.
I enjoy the 4.08 gearing! I did not notice a loss in WHP on the dyno. On the drag strip I did notice a loss in the 1/4 due to less traction with street tires and the extra shift I had to make.
On the track, at Watkins Glen the car seems to be in the powerband more often. It really depends on the track your on.
Yea thats what I was thinking too that it shouldn't show a loss on the dyno. I read on this forum and from a quick research I did on google that there is in fact a loss. I will be redynoing next week or so to see if there is a loss. Check out this thread.
https://my350z.com/forum/intake-exha...project-2.html
Scheduled appointment on Saturday to get the intakes installed and then get re-tuned.
Going to start by doing another baseline run with the current setup/tune, then install the intakes, and see where it goes. I want to re baseline because i now have the 3.9 final drive. and last time i dyno'd with the 4.08 gears (at the time was making 292whp, 264tq), the car's numbers were down to around 285/259. Bobby said every car that has a shorter gear in it, for some reason, just drops power on the dyno.
The car hit 303whp and 272tq with the 3.5 final drive in.
So basically if my baseline is 290 (where as I hit 303 with the 3.5 fd) and i gain 10whp with the intakes and retune, then i can assume 313ish whp with the 3.5 fd, no?
Going to start by doing another baseline run with the current setup/tune, then install the intakes, and see where it goes. I want to re baseline because i now have the 3.9 final drive. and last time i dyno'd with the 4.08 gears (at the time was making 292whp, 264tq), the car's numbers were down to around 285/259. Bobby said every car that has a shorter gear in it, for some reason, just drops power on the dyno.
The car hit 303whp and 272tq with the 3.5 final drive in.
So basically if my baseline is 290 (where as I hit 303 with the 3.5 fd) and i gain 10whp with the intakes and retune, then i can assume 313ish whp with the 3.5 fd, no?
03-31-2014, 09:52 PM
#17
Registered User
Thread Starter
There could be a little loss on the dyno perhaps caused by drivetrain losses. Since the FD is shorter there are more drivetrain losses.
No laptimes before after for the HR users ?
No laptimes before after for the HR users ?
04-01-2014, 06:06 AM
#19
Registered User
There is a 3.3, 3.5, 3.7, 3.9 and 4.08 FD.
I enjoy the 4.08 gearing! I did not notice a loss in WHP on the dyno. On the drag strip I did notice a loss in the 1/4 due to less traction with street tires and the extra shift I had to make.
On the track, at Watkins Glen the car seems to be in the powerband more often. It really depends on the track your on.
I enjoy the 4.08 gearing! I did not notice a loss in WHP on the dyno. On the drag strip I did notice a loss in the 1/4 due to less traction with street tires and the extra shift I had to make.
On the track, at Watkins Glen the car seems to be in the powerband more often. It really depends on the track your on.
04-01-2014, 07:01 AM
#20
Shorter gears will be advantageous in some scenarios, and disadvantageous in others. There's no one silver bullet - hence why race cars have different gear ratios per track.
Sounds like the 4.083's may not be a match for the track you're on. I'd bet they help you in some corners/straights, and hurt you in others.
For street driving, I'd think the 4.083s really make a difference (I don't have them). One thing that's always annoyed me with the Z is that there's a dead spot from a roll in the lower speeds...which is where you spend a lot of time on in normal street driving.
For example, you're cruising at 20-30mph, and want to accelerate. I suppose you could double-clutch down to 1st, but you'd probably light up the tires. In reality, you'd put it in 2nd (or already be there), but you're not in your powerband & have to wait for the upper RPMs.
The higher gears help that scenario.
Sounds like the 4.083's may not be a match for the track you're on. I'd bet they help you in some corners/straights, and hurt you in others.
For street driving, I'd think the 4.083s really make a difference (I don't have them). One thing that's always annoyed me with the Z is that there's a dead spot from a roll in the lower speeds...which is where you spend a lot of time on in normal street driving.
For example, you're cruising at 20-30mph, and want to accelerate. I suppose you could double-clutch down to 1st, but you'd probably light up the tires. In reality, you'd put it in 2nd (or already be there), but you're not in your powerband & have to wait for the upper RPMs.
The higher gears help that scenario.