Wideblock-RX-7 shifting issues

coltboostin · Post by **coltboostin** » Thu Sep 18, 2008 11:29 am

Well, as some of you know, my car has had a shifting issue from day one. It all but locks you out after 4k rpm, which is not going to work well with a turbo set up that is at full song well past 5k. Initially on the Twins, the car made 567whp on mild boost. Great, but useless since I could not shift the car.

I tried a different clutch, no change. Different flywheel, no change, different trannys, no change, new Pilot bearing, no change. The Input shaft was smoth on the pilot bearing. I was stumped

Before my thrash to get the car shootout ready-I had an idea. IF there was an lalignment issue, I could runt he car sans pilot bearing as a quick way to check. I was otu of options, so I did. Low and behold- it shifts SIGNIFICANTLY better without it. Now, I cant power shift he car, btu I can slow shift it at higher RPM's without an issue. This tells me there is an alignment issue.

I have not though of a cheap solution, since he car works well as is. I think I may just leave a small turbo on the car, and build another project to quench my big power, big trap speed needs.

Just FYI, since it seems a lot of people want to try this swap out.

jeffball610 · Post by **jeffball610** » Fri Sep 19, 2008 7:55 pm

So what would cause this slight alignment issue? I would guess that is has more to do with the bellhousing area than anything. The bellhousing should hold it true to the block. Is there a "spacer" plate between the block and tranny? What about the alignment dowl pins? I'm sure the pilot bearing is not a critical part, but if the transmission is out of alignment, it could cause other issues down the road.

Since you swapped out transmissions and flywheels already, that helps to trouble shoot it some and leaves the bellhousing or engine block area that are the likely trouble areas.

Post by **DJpowerHaus** » Sat Sep 20, 2008 1:53 am

I am using a B2600 bellhousing with an RX7 (Series 5) transmission and it shifts fine under full power (340hp) at any and all RPMs I've driven it at. Full power shifts at 8000rpm even. Not sure what your problem is. Sure its not a problem internal to the transmission?

coltboostin · Post by **coltboostin** » Sat Sep 20, 2008 12:09 pm

I cant think that all 3 trannys I have had in the car were bad?! I'd be pretty annoyed if that was the case.

coltboostin · Post by **coltboostin** » Sat Sep 20, 2008 2:20 pm

What clutch are you using?

77amc · Post by **77amc** » Sat Sep 27, 2008 11:04 pm

Now I'm no pro but what if the driveshaft is too long and jamming things up? Like ya said, 3 tranny's cant all be bad, and the pilot bushing removal made things better.. Unless the trannys were all disasembled and a gear or more was installed backward or a wavy shim or..?
Or if the rear diff was moved during the build up..?

Just my .02

E

coltboostin · Post by **coltboostin** » Sun Sep 28, 2008 8:19 pm

77amc wrote:Now I'm no pro but what if the driveshaft is too long and jamming things up? Like ya said, 3 tranny's cant all be bad, and the pilot bushing removal made things better.. Unless the trannys were all disasembled and a gear or more was installed backward or a wavy shim or..?
Or if the rear diff was moved during the build up..?

Just my .02

E

The tranny is still int he stock location, and uses the sock mount. the rear end was not moved at all.

I have gone through an ACT 2100, 2600, and now this POS South bend Clutch. removing the pilot bearing is the only thing that has helped thus far.

Mr Hyde · Post by **Mr Hyde** » Mon Oct 13, 2008 7:55 pm

Lets compare parts since we know coltboostin's been through a couple of clutches and flywheels...

DJ, what flywheel, clutch/pp combo are you using, and what shift fork/throw out bearing are you using?

Geoff

coltboostin · Post by **coltboostin** » Sat Oct 25, 2008 7:10 pm

If I stay wideblock, I will likley go with a comp or an ACT 2600, again but new