first off, i have a 95 jdm b16 sir motor which has a final drive of 4.4. i want more acceleration (and lsd) so i was thinkin of getting a 98 itr tranny (4.785 fd) but those are damn hard to come by. so my next thought was to get a 96 itr tranny (4.4 fd) and swap in a 4.785 fd since the 1-3 gear ratios are exactly the same.

first question: is that possible (im thinking yes, but jus making sure)?
two: im not too familiar with trannies..so basically..what does increasing the final drive do? will it increase acceleration in the lower gears?

any help would be awesome! thanks

 

Yes, it would work.

That would also effectively make it a closer-geared transmission than the 98+ spec ITR tranny.

The 4.40 FD ITR transmissions feature shorter 4-5 gears than the regular 4.7 FD transmissions.

I'm not exactly sure as to what all parts from the 4.7 trans you would need for the swap, but it has been done.

Changing the final drive gear of your transmission to the 4.7 will effectively multiply the torque your engine makes even greater than the 4.40 does. When you multiply torque, you go faster.

 

thanks man, that was exactly what i was looking for. appreciate the help

 

I am pretty sure you would need to swap in the '98 spec JDM ITR first gear as well. I know this is the case for installing an ATS 4.9 into any other tranny minus the '98 spec, countershaft and final drive teeth have to match accordingly, and the only way to accomplish this is to have the '98 spec JDM ITR first gear.

 

yea i was reading that on the ats website..but im not changing it to a 4.9 jus 98 spec 4.7. and the 98 spec and 96 spec first gears are the same (i think..the ratios are the same for sure). so wouldnt it be alright if the first gears are the same?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92TypeR &raquo;</TD></TR><TR><TD CLASS="quote">I am pretty sure you would need to swap in the '98 spec JDM ITR first gear as well. I know this is the case for installing an ATS 4.9 into any other tranny minus the '98 spec, countershaft and final drive teeth have to match accordingly, and the only way to accomplish this is to have the '98 spec JDM ITR first gear.</TD></TR></TABLE>

haven't heard of that but now that you brought up the ATS thing, can someone confirm?

 

If you already have a B16 hydro trans, you already have a "ctr" transmission minus the LSD. The ratios of the CTR are the same as a B16, 1-5 and 4.4 final drive. The only thing different is that the CTR came with an LSD.

I don't know about you but a 4.785 geared B16 trans sounds like punishment on the expressway to me.

If you want more acceleration, maybe get a GSR shortblock and put your B16 head on it, a little more torque and potential than a B16. Then add an LSD to your B16 trans. You'll need a GSR differential's ring gear to make it fit.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92TypeR &raquo;</TD></TR><TR><TD CLASS="quote">I am pretty sure you would need to swap in the '98 spec JDM ITR first gear as well. I know this is the case for installing an ATS 4.9 into any other tranny minus the '98 spec, countershaft and final drive teeth have to match accordingly, and the only way to accomplish this is to have the '98 spec JDM ITR first gear.</TD></TR></TABLE>

that's is exactly what you need for both the ATS and the ITR

i have the 4.785 fd and it sits at about 3,900 at 80 mph (that's a guestimation and my tires may be smaller than normal)

I would go with the 4.9 ATS, it's gonna cost the same or maybe a little more and will cost the same to have put in, plus ATS sells it as a kit with the first gear and everything else you need... .If you are concerned with highway MPH, put in an LS 5th gear while you are at it and that should put you right back to around where you started off with your 4.4 FD

Dave

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JohnnieChimpo &raquo;</TD></TR><TR><TD CLASS="quote">I don't know about you but a 4.785 geared B16 trans sounds like punishment on the expressway to me.</TD></TR></TABLE>


yea, haha. he forget to say that its for autocrossing/road racing only, he has another car for a dd. youre welcome mike haha

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JohnnieChimpo &raquo;</TD></TR><TR><TD CLASS="quote">If you already have a B16 hydro trans, you already have a "ctr" transmission minus the LSD. The ratios of the CTR are the same as a B16, 1-5 and 4.4 final drive. The only thing different is that the CTR came with an LSD.

I don't know about you but a 4.785 geared B16 trans sounds like punishment on the expressway to me.

If you want more acceleration, maybe get a GSR shortblock and put your B16 head on it, a little more torque and potential than a B16. Then add an LSD to your B16 trans. You'll need a GSR differential's ring gear to make it fit.</TD></TR></TABLE>


you have no clue and no real life experience.....

a final drive is the best mod on a b16!!!! EVER.....rpms jump 300-400...ohhhh noooooo soo much punishment on the freeway!!

a b16 with a 4.785 is gonna be faster than a gsr with a 4.4 tranny!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chad &raquo;</TD></TR><TR><TD CLASS="quote">you have no clue and no real life experience.....</TD></TR></TABLE>

I couldn't agree more. The ATS FD has been the best mod I've done, even compared to the 2.0L build!

There is so much internet myth about increased wear/tear and poor feul efficiency with a higher FD...but they are all just that, myth. The ONLY reason I would deem reasonable to why you would want a lower cruising RPM is if the car is just too loud to comfortably drive, which is the case sometimes.

This thread reminds me of some of the posts in this thread

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chad &raquo;</TD></TR><TR><TD CLASS="quote">


you have no clue and no real life experience.....

a final drive is the best mod on a b16!!!! EVER.....rpms jump 300-400...ohhhh noooooo soo much punishment on the freeway!!

a b16 with a 4.785 is gonna be faster than a gsr with a 4.4 tranny!</TD></TR></TABLE>

no clue, no experience? You're half right. I have no experience with little B16s, I've only played with GSRs, B20s and H22s. I have installed a ITR LSD in a B16 trans and it required the parts I said it would.

Reguarding punishment on the freeway, I meant my punishment, not the engine's. You're correct the revs at 70mph would only be 350+/-rpm. I just can't justify spending $1200 for a JDM ITR trans or (I'm not sure what the final drives cost) $350 + installation on a final drive that like you said will only change the revs slightly, 35mph @ 8000 vs 38mph in 1st. For me I feel the money would be better spent on some displacement or a nitrous kit not 400rpm.

 

well I switched to the JDM tranny out of necessity....and noticed a very subtle difference, it's like my car just suddenly woke itself up, same power, just seemed like more was readily available ....it's hard for me to explain,

Dave

 

Ok. guys I have related question and don’t want to start a new topic so I’m asking here.
I have eg9 with y21 tranny and 4.266 FD – I want to buy and intstall 98 ITR FD set (4.785 with the first gear). Will it fit into my y21 with no problems (just p&p)?

Thanks

 

so a 4.9 final drive in a 96-97spec itr tranny isn't all that bad on the highway?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by UNKNOWN_MEMBER &raquo;</TD></TR><TR><TD CLASS="quote">so a 4.9 final drive in a 96-97spec itr tranny isn't all that bad on the highway?</TD></TR></TABLE>

I made a 4200 mile roadtrip on my '96spec w/ATS FD.

I like it because you will never have to downshift to pass people. You'll know exactly what I'm talking about once you drive one with that setup.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JohnnieChimpo &raquo;</TD></TR><TR><TD CLASS="quote">

no clue, no experience? You're half right. I have no experience with little B16s, I've only played with GSRs, B20s and H22s. I have installed a ITR LSD in a B16 trans and it required the parts I said it would.

Reguarding punishment on the freeway, I meant my punishment, not the engine's. You're correct the revs at 70mph would only be 350+/-rpm. I just can't justify spending $1200 for a JDM ITR trans or (I'm not sure what the final drives cost) $350 + installation on a final drive that like you said will only change the revs slightly, 35mph @ 8000 vs 38mph in 1st. For me I feel the money would be better spent on some displacement or a nitrous kit not 400rpm.</TD></TR></TABLE>

Hmm.....guess you don't know who Chad is?

Anyways, the ATS fd with all necessary parts is somewhere around $750. I have never installed the kit, but I have disassembled a tranny so if you have some wits and some tools the installation is free. I would love to get the ats final to help with acceleration instead of adding more hp.

 

so would you recommend a 4.7 or 4.9 fd in a 96 itr tranny?

 

either one is great, but if you are gonna have the tranny out might as well go with the 4.9 and put in the LS 5th gear for those highway trips

I would do it and know that you have basically nothing more to do to the tranny anymore....(except a stronger LSD) unless you start thinking about gearing for road racing or if it puts you into fifth gear with drag racing...but i doubt that would happen

Dave

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mr abstract &raquo;</TD></TR><TR><TD CLASS="quote">so would you recommend a 4.7 or 4.9 fd in a 96 itr tranny?</TD></TR></TABLE>

4.9 and keep the ITR 5th, you'll regret it if you change it out.

 

2 for 2 for the 4.9 fd. sounds good to me. thanks for the input guys!