I need to open my Trans to replace the Syncros and while I'm there was thinking about installing 4.923-1 final drive. What are the pros and cons with this mod? I know it should lower my top speed but that's fine. Basically is there anything I need to know before doing this mod?

 

Is this a track car or daily driver?

 

hopefully you have a quiet exhaust system if you do a lot of hwy driving.

 

Track car but I use from time to time to go to work on 50mph roads to and from. I have a buddy club exhaust that sounds nice, not too loud.

 

https://honda-tech.com/forums/showth...ts+final+drive

 

It also depends on the type of track you go to. If you go to a track with a lot of high speed straights, you'll run out of gear really quickly. If you race on short courses like Tsukuba (for example) 4.9 is really nice, but you'll be very busy. I think 4.7 is the best of both worlds, and good enough for a daily driver. I drive my car for 4+ hours on the highway with no stereo system and its not so bad.

4.9 is very purpose built and I personally would use it only if I knew for sure that my car is track only, and the track has straights no longer than a mile long.

 

Prepare for a lot of shifting. What final drive is in the car now? The acceleration increase alone is far worth it imo even for a daily driver.

 

http://www.youtube.com/watch?v=N1Dv_...0&feature=plcp

 

Stock, what is it 4.4? I thought it didn't make the car any faster in a 1/4 mile, just hits the vtech sweet spot faster no matter what gear you're in?

 

Nice!

 

I've read endless comments and threads on this issue but still think this mod is the way I'll when my R is running again. Unless I've overlooked it I've never heard of anyone removing the 4.928 final drive after installing it.

 

http://teammfactory.com/gearcalculat...ission+1+%26+2

OP If no one has ever pointed this out to you I hope you find it helpful. Notice though the graph is shown with 1st gear also changed out also.

 

As said before you will be busy... I don't track my R but it is a weekend warrior and just driving around town I find myself in 4th or 5th. I love it, this coming from the stock FD and also having a JDM 4.785 in my GSR before.

 

FD rocks

 

I pray when I finally get my R running I'm not disappointed by the 4.9 F/D coming from a boosted set up. I've read about all types of gear changes till I'm blue in the face so it's probably going to be trial and error. Gotta just try I guess.

 

just got mine installed a couple of days ago.. and i LOVE IT! best mods ever,
although i got a straight cut FD. It whines like a supercharger lol it kinda gets annoying from time to time lol but worth it IMO

 

^^^I'm sure it's loud being straight cut. So what kind of F/D is it and what made you go with a straight cut set up? Is that the only mod to your trans?

 

If yours is straight cut it is a 4.928 made by Gear-X. MFactory is the only company that makes a 4.923 (semi-helical).

Unless you're making a lot of power there are only a handful of tracks you will top it out at. Unless you're on a roval there are only a couple on the east coast. One of my sponsored racers (Andrew Meeks a.k.a. Hooch'n) runs the MFactory 4.9 FD and helical LSD and topped it out on the back straight at VIR but nowhere else that I know of.

 

I'm still on the fence of a mild/low boost build or the 4.9 gearing. Lost all interest in drag racing and don't really care about tracking either. I'll just keep flipping the coin till I come to a decision of what route to take.

 

i love my 4.9 fd

 

You keep the stock 1st Dan or use the 3.07?

 

kept my stock first gear....its pretty dam short but i don't use first at the track so it really doesn't bother me. on the street the 4.9 it feels sooo good. on the highway its not bad but i drive slow anyways and keep it at about 4k or less.

 

Looking at MFactory's gear calculator it looks like the 4.9 would make the car very aggressive on the street. The reason I asked about keeping the stock 1st was traction. Being geared that low I figured it would just light the tires up even if the car only had bolt on parts and tuning.

 

If you're going to do a low power boost setup (300whp or less) run the MFactory 4.05 FD and long R/R close gear set (1.636, 1.313, 1.028). One of my customers is running this in his low power boosted track car (270'ish whp iirc) and is happy with it thus far. Another also runs it in his N/A track ITR (166whp Mustang) and prefers it over a 4.928 on the street (only tracked the 4.928 once in his other ITR so he didn't feel he had a valid comparison on track).

 

Changing all those gears/ratios sounds good but that's all in perspective as to how/what turbo would be desired. Might work great but being me and not wanting to break the bank I'd probably just leave the ITR tranny stock for street use.