Ring and Pinion Gears (help)

[mrace240sx]

Has anyone out there done a ring and pinion gear swap on their S13 or S14? Nissan Motorsports has the set for $430 and Im trying to get some info about it.
I am looking to lower the gear from our stock 4.083 to a 4.636, Ive heard it can lower your quarter mile time as much as a full second. You lose some top end and get worse
gas mileage but this isnt a daily driver so I really dont care, I just want to go fast hehe.

I know Don from PDM has this listed as one of the mods he did to his S13, I just want to know how hard it is to do, and any reviews or info about it, and why nobody else seems to be doing it? Ive heard it is one of the cheapest and most noticable mods you can do, yet nobody seems to be doing it?!?!

I am seriously considering it as an option to turbo. hell, a CAI, catback exhaust, headers, pulleys, and gear swap just might get me fast enough for alot less money.What do you guys and gals think?

[Jeff240sx]

Hey man.
I don't think that I would raise the ratio with a turbo.  If anything, it would seem logical to want to be in the turbo spool up for as long as you could.
Plus, you would have to do a map of your gears, to find out what rpms each shift would put you at, and if it is in the turbo spool-up area, or below it.
Running the numbers on CarTest:
Stock
0-60 - 7.2
1/4 mile - 15.8 @ 87.8mph in 4th
Top Speed - 133
EPA - 23.3 combined
Swapped ring and pinion
0-60 - 7.4
1/4 mile - 15.7 @ 88.4mph
Top Speed - 129
EPA - 21 combined

I wouldn't do it.  If anything, I'd lower the ratios, like 300zx tt's have 3.86 or something, and Silvias have 3.7-ish.  That is for more time in the boost zone.
-Jeff

[whateverjames]

i'm not going turbo, i'm going with all motor SOHC, and i plan on getting the nismo 3.70 gears. my car could the gears now actually, but i'd like to get a little more power and make better use of the gears.

[wherezmytofu]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (mrace240sx @ Mar. 28 2002,12:23)</td></tr><tr><td id="QUOTE">Has anyone out there done a ring and pinion gear swap on their S13 or S14? Nissan Motorsports has the set for $430 and Im trying to get some info about it.
I am looking to lower the gear from our stock 4.083 to a 4.636, Ive heard it can lower your quarter mile time as much as a full second. You lose some top end and get worse
gas mileage but this isnt a daily driver so I really dont care, I just want to go fast hehe.

I know Don from PDM has this listed as one of the mods he did to his S13, I just want to know how hard it is to do, and any reviews or info about it, and why nobody else seems to be doing it? Ive heard it is one of the cheapest and most noticable mods you can do, yet nobody seems to be doing it?!?!

I am seriously considering it as an option to turbo. hell, a CAI, catback exhaust, headers, pulleys, and gear swap just might get me fast enough for alot less money.What do you guys and gals think?</td></tr></table><span id='postcolor'>
gear ratio is whats it's all about...

shorter gears(gear with higher number) faster acceleration because the wheel turns faster, they make u stay at higher rmps causing less mpg, lose top speed

longer gears (geat with lower number) slower acceleration becuase the wheel doesnt turn as fast, takes londer to get to higher rmps, better gas and higher top speed

herea a gearing calculator to help you better understand gearing. notice that this is the gearing numbers u can achive higher mph from momentum like 2-3mph..also dont explect a 155hp engine to pull all the way tot he max mph
http://www.geocities.com/z_design_studio/

<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/cool.gif" border="0" valign="absmiddle" alt=':cool:'>