88/89 CRX Tranny Issue

[bbreon]

OK, I have a ITA CRX. Have had this damn Tranny out way too many times. I've had it to King Motorsports twice now with no fix. I bought a King final drive (4.93) cause I wanted to try the 4.93. It had to be modified by them to fit and they did the install. At the same time, I told them I was having problems with 5th to 4th shifting. I had them put the FD in last Summer. When I got it in the car and out in February, I still had problems with the 5th to 4th. Seems to only happen when I am "briefly" in 5th. When I am in 5th for a long straight, I don't have a problem.

Also, seems when I took the car out in February, not only did I have problems with 5th to 4th, but, I also had a the mainshaft seal folded by King, sooooo, I got lots of oil in the clutch and after 3 sessions, it was slipping in 3rd, 4th, and 5th.

So, I pulled the tranny, again. And I mailed it back to King. They fixed the seal, replaced the 3rd and 4th shift forks and replace the bearings but couldn't findy any thing with 4th or 5th. I put it back in the car. Cleaned up the clutch from before as it was new.

Well, at the track, first time out, 5th to 4th is still sticking. Again, only when I go into 5th briefly, works fine when I am in 5th for a long section of the big straight. But, clutch starting slipping right away. Pulled the started, looked in at the clutch, looks to be dry. I don't think the seal is leaking, haven't pulled the tranny yet though.

So, when a clutch disc gets fouled with oil, is it junk?

And, any idea what is causing my 5th to 4th issues?

[Tom Blaney]

Two suggestions,

first the clutch disk is pretty much junk, even soaking is gas or paint thinner is not going to clean it off, so buy a new one.

Second try a different gearbox, I'm not sure what King could be doing wrong, but something is not aligned properly of not seating for it to give you that much trouble.

CRX gearboxes are pretty cheap and you would be starting out with a different source. Also I found that the car was much faster with 4.5 and 4.7 gearsets.

[bbreon]

Tom, I was hoping you would reply.

I figured as much on the clutch disk and should have known better.

As for the tranny, I am thinking of doing that. Trying to decide now if I send it back to King to have them fix it again or not. I do think it is related to their final drive and the countershaft not having the 4th and 5th gears aligned correctly. Is that possible.

Have you used the Gear X finals? They didn't have these when I got the 4.9 from them but do carry them now. I had an 4.7 ATS crater on me 2 years ago, that was when I tried the 4.9

I'll tell you what, the 4.9 REALLY pulls nice in the corners in 3rd. Top speed with 225's is still high 120's. Why do you think the 4.5 or 4.7 is faster?

[Chip42]

hey - I don't know which CRX model you have, but the 4.7 is a very good fit for the powerband of the Si. the DX might want the 4.9, I have no idea - remember that you can go "over" the power point in the revband and wind up peddling downhill, in a fast enough strait in the Si with the 4.9 this is a very real concern.

as for misalignment on the output shaft (there really is no lay shaft in that box) it's not very likely as it would causde a lot of problems you are not complaining about. some aftermarket finals do have shorter (axially) than stock splining; I've not had a problem with it, but it's something that I could see causing your issues.

you said king had to modify the 4.9 gearset for you. how and why?

Also, 3/4 are 1 fork and 1 selector ring, and 5th is its own ring shares fork with reverse. your problem might be in the selector shaft not wanting to release from the 5th/reverse fork. can't explain the time-in-gear dependant part, though.

[bbreon]

Let me back up. I built the tranny in 2002 with the ATS 4.73 and a Quaiffe. I did the work myself, so I am somewhat familiar with the inerts of the tranny.

In 2007, my ATS 4.73 cratered. I bought a 4.93 from King and attempted to install. The countershaft was too long and the case wouldn't go on. It appeared that King was trying to make these work on mutiple transmission years. I send the countershaft to King. They cut the shaft and placed a spacer between 4th and 5th. I tried to reinstall again. Still no dice. I was in a huge hurry, race the next day, so I pulled the spacer and the case went on.

I went racing, but had problems with 5th to 4th. When I got back, I pulled the tranny and sent the whole thing this time to King.

They said they had alignment issues with 4th and 5th and the shaft was still too long. They corrected and returned.

That leads to this past February 09. First time out since they "fixed". They folded the seal on the mainshaft and it leaked oil into my clutch. Still had 5th to 4th issues.

I sent back to King again. told them to do whatever to make it right. They replaced bearings (never had been replaced, felt a good idea). They said 3/4 shift fork was worn, replaced. They said 5th looked good. All synchros good. They said that the 5th shift arm to shaft had one ball and spring combo and they said it needed two pairs. They installed.

I put back in the car. Made the mistake of reusing the clutch disk. Still trouble in 5th to 4th.


As for the gear, if my HP curve shows no real power gain over 6800 rpm and at 7200 in 5th with 225's I have a 130 mph top speed, I should be fine. Question is, and I don't have Data Acq, is if my HP curve and my typicall RPM ranges are matched.

Tom, do you have Data Acq that shows typicall RPM ranges for the 4.5 or 4.7 vs. HP Curve to show that the 4.5 or 4.7 is a better choice?

[bonespec]

Seems King tried to make a Hydro counter shaft work in a cable tranny case, not gonna happen!

King is now selling GearX FD's from Kiwi/Jeff Owen, I'm also a unlisted seller.

What area are you in? I'm in Cincy, Ohio and if you are close I can offer to look at it.

Ian Green sheared teeth off his 4.7 ATS FD in his ITA CRX in 2007, thought it was just an axle. Come June 2008 it was found the FD was fubared and I installed a GearX 4.9 FD so he could make ITFest, and he did with the help of Kevin Ruck and his garage/lift.

FYI the cable countershaft and mainshaft are 3mm shorter than the hydro counterparts.

Since I don't check in here often, I can be found on HnodaTech, RRAX, or you can email me at bonespec at gmail dot com

Here is a few comparison photos of 4g cable vs 5g hydro shafts and shifter forks.

http://s107.photobucket.com/albums/m307/bonespec/Transmission/General/4g%20vs%205g/

[R2 Racing]

Brent, seriously, if you're having Honda D-Series tranny problems, just have Bone fix it up. He's not that far from you, and it'll be done right. Also, if you're looking at a GearX, he can hook you up on that too.

As for the FD ratio, I know several really fast CRX's that run the 4.9. You know, one's that go to the ARRC, and routinely stand up on the podium.

[Tom Blaney]

Bret, sorry I didn't get back sooner, but I suspect that if you blew the box, and then had king work it over a couple of times, there is something inherantly wrong with it now. Either the bearing are fitting sloppy, or the spacers are loose etc. If the quaiffe is still good which it sounds like it might be easier to start over again, since the most expensive part is the diff. I have never had to fiddle with the parts to upgrade the box, either they fit or they don't. If you have to machine it than it doesn't fit simple as that.

I have used Gear-X before and they work fine, I converted from a 4.7 gear set to a 4.5 since I think the 4.5 is better overall than 4.7. I never liked the 4.9 since it twisted the box too far above the powerband.

I have a box and a new 4.5 and I think by looking at what is in the old box, put some new syncro's & bearings in a new case you will run fine.

Let me know, and we can work out the details.

[Xian]

x2 for having Bone do the work... solid reputation and he knows D-Series boxes inside and out. Also, FWIW, the "RRAX" site he referenced can be found at www.roadraceautox.com (http://www.roadraceautox.com).

Christian

[bbreon]

Guys,

Thanks for the comments, this was the type a analysis that I was looking for. Fortunately, (or maybe unfortunately) the box is back at King. I think Bones is right, I think that they made the hydro fit the cable. I do know of 3 others that have this setup from King and have had no problems. So, that being said, they should be able to make it work. I'll give them one more try, then, I will start with a new tranny as I suspect I can't use anything they have touched with the Gear X. I'll keep you posted.

Tom, you said you have a spare tranny?

[Tom Blaney]

Yes I have a box and a Gear-X 4.5