Installed 3.9 FD and worse acceleration
03-31-2008, 11:16 AM
#22
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Originally Posted by raditz
I have just installed the 3.9 FD on my revup, and tested it with a friends nonrevup Z, and now I have worse acceleration than before. Now all the advantage that I take on him thanks to the shorter gearing, I loose it in the moment that I change sooner than him.
All the Z that have installed the 3.9 FD in Spain have the same problem...is that normal aswell there in the States???
All the Z that have installed the 3.9 FD in Spain have the same problem...is that normal aswell there in the States???
If you just race a short difference, it might look like he's faster because you have the shift first. Go to the track and race him for a quarter mile where you'll both have to shift several times. If you're racing a similar car and you have to shift and he doesn't, he will always look faster. You need to race for a longer distance.
Another thing is that your car might spin the tires more in low gear now. You might need to alter your starting line driving technique or get better tires.
03-31-2008, 09:52 PM
#26
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Originally Posted by Alberto
No-last time I checked the UTEC didnt log shifts times lol...
03-31-2008, 09:54 PM
#27
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Originally Posted by __jb
How are you and your friend racing? You should gain the distance (and more) back when he shifts.
If you just race a short difference, it might look like he's faster because you have the shift first. Go to the track and race him for a quarter mile where you'll both have to shift several times. If you're racing a similar car and you have to shift and he doesn't, he will always look faster. You need to race for a longer distance.
Another thing is that your car might spin the tires more in low gear now. You might need to alter your starting line driving technique or get better tires.
If you just race a short difference, it might look like he's faster because you have the shift first. Go to the track and race him for a quarter mile where you'll both have to shift several times. If you're racing a similar car and you have to shift and he doesn't, he will always look faster. You need to race for a longer distance.
Another thing is that your car might spin the tires more in low gear now. You might need to alter your starting line driving technique or get better tires.
04-01-2008, 01:19 AM
#28
Originally Posted by raditz
I have just installed the 3.9 FD on my revup, and tested it with a friends nonrevup Z, and now I have worse acceleration than before. Now all the advantage that I take on him thanks to the shorter gearing, I loose it in the moment that I change sooner than him.
All the Z that have installed the 3.9 FD in Spain have the same problem...is that normal aswell there in the States???
All the Z that have installed the 3.9 FD in Spain have the same problem...is that normal aswell there in the States???
04-01-2008, 07:15 AM
#29
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I raced a couple WRX's with full boltons and we were all dead even before my 4.08's...still dead even after until I got into the powerband in 4th and I really walked off bad, worse than I did on him when we were both stock. the tighter gearing really only helps me with coming out of corners....i'm at a higher RPM than I was before so I've got more power on tap. it really helps with Solo II stuff, I wouldve been a good second and two or three tenths slower with my stock final drive ratio (around a high 30's course).
Last edited by ke0ki2k; 04-01-2008 at 07:19 AM.
04-01-2008, 03:42 PM
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for some reason my 5at g35 is a bit slower when racing my friends 6mt 350z after getting my 3.53 pumpkin installed. its good from a stop but by top of 3rd its dead.. we usually go neck and neck till 120 but now once i hit 4th its all over for me. not trying to thread jack but since were on the subject already...
04-02-2008, 01:36 AM
#34
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I have datalogged a launch and I have a best shift time of 0,3 seconds and a worse of 0,5, this time is from WOT to WOT.
I also have used a Car Performance Software, introduced the data of my car with both gears, and doesn't matter what shifting time you tell the program to use, the 3.5 gearing accelerates faster in 400m, 1000m, 2000m...
I also have used a Car Performance Software, introduced the data of my car with both gears, and doesn't matter what shifting time you tell the program to use, the 3.5 gearing accelerates faster in 400m, 1000m, 2000m...
04-02-2008, 02:34 AM
#35
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Originally Posted by Alberto
Its your shifting. You are losing more ground because you are shifting more often and you arent good at it. If you could learn to NOT lose momentum during shifts, you would be faster at all mph and rpm's and wouldnt fall back at those spots.
I am not being mean, just honest, I know EVERYBODY can drive like pro's online....
edit-before anybody steps in and tries to say "driving from a roll isnt a big factor", its HUGE, as can be seen below.
http://www.youtube.com/watch?v=-gafwal26KU
I am not being mean, just honest, I know EVERYBODY can drive like pro's online....
edit-before anybody steps in and tries to say "driving from a roll isnt a big factor", its HUGE, as can be seen below.
http://www.youtube.com/watch?v=-gafwal26KU
04-02-2008, 06:23 AM
#36
Originally Posted by Sensi09
Sure shifts make a difference, but you were pulling from the beginning before any shifts were made.
04-02-2008, 08:26 AM
#37
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Thread Starter
Originally Posted by Alberto
Thats not the point. The point is look how better shifting can make 5+ cars difference. And thats with only 2 shifts involved! From a 1st gear roll its an even bigger difference.
What I was trying to say with that post is that ME (with my shift times) made better acceleration with the 3.5 FD than with the 3.9
04-02-2008, 09:11 AM
#38
Originally Posted by raditz
But what would happend if the other driver shifts as fast as you? is then the 3.9 FD worth it?
What I was trying to say with that post is that ME (with my shift times) made better acceleration with the 3.5 FD than with the 3.9
What I was trying to say with that post is that ME (with my shift times) made better acceleration with the 3.5 FD than with the 3.9
04-02-2008, 10:20 AM
#39
Originally Posted by Alberto
Thats not the point. The point is look how better shifting can make 5+ cars difference. And thats with only 2 shifts involved! From a 1st gear roll its an even bigger difference.
As food for thought, raising the rev limiter a bit as you raise the FD ratio can help mitigate the difference in shift points.
04-02-2008, 10:23 AM
#40
Originally Posted by rcdash
Well let's be fair - differences are exaggerated in your car because of the turbo. You are maintaining momentum in all aspects of the drivetrain and turbo as you shift. That's a huge plus as you maintain energy levels in turbo and engine...
As food for thought, raising the rev limiter a bit as you raise the FD ratio can help mitigate the difference in shift points.
As food for thought, raising the rev limiter a bit as you raise the FD ratio can help mitigate the difference in shift points.
and raising the rev limiter has already been brought up.