Hey guys I've been searching around but I have not found what I need yet. I have an '89 CRX DX 5spd in great condition and I am under the impression that the only difference in the Si and the DX trans is the final drive? So if this is true what FD will bolt in to my '89 DX??. 88-91? 89-91? '89 only? I know there are some differences in the 88-89s and the 90-91s... Really the bottom line is that I have an Si tranny that is 20 spline (not sure what year) and it matches my DXs 20 spline so I am hoping I can use the Si FD since the shift fork is broken and 2nd gear grinds.

I just figured this may save me some time so point me in the right direction guys, thanks.

 

You should be able to do what you're proposing. Just make sure the bearings are the same size. I can't remember off the top of my head if there's any difference between the 89 and 90-91 bearing sizes.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wiZCo &raquo;</TD></TR><TR><TD CLASS="quote">You should be able to do what you're proposing. Just make sure the bearings are the same size. I can't remember off the top of my head if there's any difference between the 89 and 90-91 bearing sizes.</TD></TR></TABLE>

Yeah I wish I knew the year of the Si trans for sure but that may not be a problem since the splines are the same. If I have a break at work tomorrow I'll be able to break open my DX and just start comparing the two to see what may be different, just wanted to try and get a heads up here first

 

Isn't 88 different spline count over the 89-91. Again though I don't know about bearing size.

 

Swapping a diff over isn't as easy as 'bolt out, bolt in'. You need to shim, and triple check the heck out of it. Ask 2point2, he recently rebuilt his H22 tranny.

I always thought it was easier to swap shift forks then diffs.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX Toad &raquo;</TD></TR><TR><TD CLASS="quote">Isn't 88 different spline count over the 89-91. Again though I don't know about bearing size. </TD></TR></TABLE>

Yeah, 21 vs. 20. This will be an issue of bearing size and shimming it properly like ludesrv pointed out.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX Toad &raquo;</TD></TR><TR><TD CLASS="quote">Isn't 88 different spline count over the 89-91. Again though I don't know about bearing size. </TD></TR></TABLE>

Yes the 88 is different but not sure the count, 21 or 22 maybe?. either way my '89 is 20 spline so I know the Si is at least an 89 or newer. If bearings are bad I'll just buy new ones so no big deal there.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ludesrv &raquo;</TD></TR><TR><TD CLASS="quote">Swapping a diff over isn't as easy as 'bolt out, bolt in'. You need to shim, and triple check the heck out of it. Ask 2point2, he recently rebuilt his H22 tranny.

I always thought it was easier to swap shift forks then diffs.</TD></TR></TABLE>

I know what you mean, lol. The plan is to just swap the ring gears and use as much of the DX parts as possible to disturb the DX tranny as least as possible so to speak. I'm pretty sure the Diffs would just swap over but I think that would be more trouble likely.

I am using this to finally get some hands on experience with trannies, I've worked on Hondas in some form or another now since '96 and I somehow just never messed with transmission internals. I am learning alot for sure.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wiZco &raquo;</TD></TR><TR><TD CLASS="quote">Yeah, 21 vs. 20. This will be an issue of bearing size and shimming it properly like ludesrv pointed out. </TD></TR></TABLE>

but luckily not an issue in this situation


Modified by VtecSyndrome at 9:27 PM 9/19/2007

 

Well I am suprised nobody else chimed into this one? being that this is so straight foward. anyway for anybody that cares or for future people that find this thread through archive search I decided I would post my results to not leave this question unanswered like so many other deadend threads. Not to much to say about it other than yes, the Si final drive does bolt right in place of the DX parts. All I needed to swap was the main shaft since it was 16 teeth to the DXs 18 teeth and the ring gear from the differentials, Si=68 teeth and the DX=70 teeth. I also went ahead and swapped on all my DX gears and synchros since they looked flawless compared to the Si's, the blocker rings were showing some flatness instead of looking perfectly round like they should. If the Si gear set looked as good I could have just swapped the whole unit and saved some time but this way I know I am all good. and on to the pics:

Heres the DX tranny freshly opened up

Here was the culprit behind the 2nd gear grind the guy (who I bought it from) mentioned, broken freakin shift fork!!




And everthing taken out (other than shift rods and bearings)




Don't forget the Diff bolts are reversed thread!!


All the main shaft gears taken off and spread out

DX main shaft next to Si shaft and just in case your curious for some reason, no the DX shaft will not even spin or fit with the Si ring gear. I tried just for the hell of it DX=18t Si=16t


And going back together in the order everything came off


And VOILA!!! My Dx tranny is now an Si! And one more thing if your curious, the bearing sizes on the 2 diffs are different sizes so just swapping the diffs over would not work. Maybe if you had the same years it would but again I had an '89 DX and used parts from a '91 Si so that may be the only reason it would not work for me.
Thats pretty much it, I still have to put the case back on and then paint it but hey, that's the easy part.

 

 

yes it will

 

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

wtf???! are you kidding me? no freakin **** it fits ..way to jack your post count nOOb! why don't you actually read more than just the title before becoming captian obvious with your genius post.

 

so what did you you torque your fd and the main shaft bolt to....
i just did the same but i put a 88 si in a 91 dx.... talk about a biotch....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1989rexsi &raquo;</TD></TR><TR><TD CLASS="quote">so what did you you torque your fd and the main shaft bolt to....
i just did the same but i put a 88 si in a 91 dx.... talk about a biotch....</TD></TR></TABLE>


Torque?? I torqued it with my 1/2 impact, no spes. I know some peole will flame me for it but it will only be people that don't realize this will not be a problem, Torque head bolts, rod bolts and thats just about it. Everything else I never torque nor do my other Mechanic friends. We've worked on enough Hondas to know how tight things need to be and what does and does not need to be torqued. And my "mentor" (so to speak) races in the Honda challange and has been for about 3-4 years now, NEVER had a problem due to improperly tourqed bolts (never will either)

 

funny thing.. that is what i did also coulndnt find any specs...

 

Can you "feel" the difference in the two?

I have a 90 STD that I just put a 5-spd DX tranny in, I got the tranny for free, but had to replace three bearings and the IS seal, I have a SI tranny in my garage that I want to put an LSD in first.

The DX tranny alone made the car a whole different car and so much more fun to drive.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GreenBean &raquo;</TD></TR><TR><TD CLASS="quote">Can you "feel" the difference in the two?

I have a 90 STD that I just put a 5-spd DX tranny in, I got the tranny for free, but had to replace three bearings and the IS seal, I have a SI tranny in my garage that I want to put an LSD in first.

The DX tranny alone made the car a whole different car and so much more fun to drive.</TD></TR></TABLE>

I have not put it the car yet but yes, the Si trans is ALOT better than the DX. The DX is alot better than a 4spd as well which is what the STD is, the DX tranny does suck though. If you think the DX tranny made the car fun to drive then you will probably think the Si feels like a freakin Type R.

 

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

I have not put it the car yet but yes, the Si trans is ALOT better than the DX. The DX is alot better than a 4spd as well which is what the STD is, the DX tranny does suck though. If you think the DX tranny made the car fun to drive then you will probably think the Si feels like a freakin Type R.</TD></TR></TABLE>

The Si trans has it all over the CRX/Civic DX trans. I know from experience, WHY CAN'T I HAVE MY LS/VTEC YET!!!!!!!!!!!! Sigh

 

Looks good!

I love cracking open transmissions.

 

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

The Si trans has it all over the CRX/Civic DX trans. I know from experience, WHY CAN'T I HAVE MY LS/VTEC YET!!!!!!!!!!!! Sigh</TD></TR></TABLE>

It's cause you are spending too much time on HT.

 

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

The Si trans has it all over the CRX/Civic DX trans. I know from experience, WHY CAN'T I HAVE MY LS/VTEC YET!!!!!!!!!!!! Sigh</TD></TR></TABLE>

Well apparently your not spending enough time on the streets selling your body, I mean come on man you got an LS/Vtec to BUILD!!! Now go get your ***** on, NOW!!


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

I love cracking open transmissions. </TD></TR></TABLE>

Thanks, I too love cracking these biotches open now. makes me feel real smart like (in voice of forrest gump)


Modified by VtecSyndrome at 7:35 PM 9/24/2007

 

sorry I take the weekends off from H-T! LOL!

 

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

It's cause you are spending too much time on HT.</TD></TR></TABLE>

I guess

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

Well apparently your not spending enough time on the streets selling your body, I mean come on man you got an LS/Vtec to BUILD!!! No go get your ***** on, NOW!!
</TD></TR></TABLE>

Well at $0.50 it takes a while, and you haven't been calling as much.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GearSpeedEF7 &raquo;</TD></TR><TR><TD CLASS="quote">sorry I take the weekends off from H-T! LOL! </TD></TR></TABLE>

Yeah you miss so much. How can you live like that.

 

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

Yeah you miss so much. How can you live like that. </TD></TR></TABLE>

Makes me a happier man and free from the noob take over from Friday night till Monday morning!