Originally Posted by amunoz3 (Post 9577339)

okay guys still beating the crap out of it with 360 whp lol my tires are bald now from wheel spin 1st and 2nd gear heh lol. give me one more week of beating it and ill say anything 360 whp and down is worthless for a manual swap

Originally Posted by grimple1 (Post 9605740)

well that's not really a fair comparison. a stock auto tranny doesn't have the rear gears or high rpm stall that would be comparable to a manual. I'm not sure I can think of one factory stock vehicle that does.

I understand the argument but I don't really think it's a fair comparison. Does anyone run a 5-speed at the drag with stock clutch?


The auto's potential lies in it its consistency with shifts and constant boost during shifts. Currently, the FD manual trans potential lies in it's ability to hold higher hp (which is what we're trying to figure out on this thread - where does the auto tranny detonate due to hp) and an increase in "driver involvement."

That being all said, I think the auto tranny on these cars has had almost no serious testing on what it can and can't do. The supra guys constantly lay down 600s on their Getrag auto transmissions. I'm not saying Mazda has such an auto transmission in the FD; however, I don't think it's as fragile (or non-potentate) as auto owners have been led to believe. Course we don't actually know b/c the auto owners are told to "swap it for a 5-speed." :icon_tup: Think of this thread as a research thread and not a "auto vs. manual" debate.

Originally Posted by Bernardd (Post 8434831)

This is a link to mods I've done on my datsun jatco 3n71b. I also have a zip file with the rebuild info for nissan jatco's from keas. You might be able to apply it to the mazda trans. PM me with an email address to send it to if you want/need it.

http://www.z31performance.com/forum/....php?f=3&t=889

Originally Posted by bajaman (Post 9697600)

No air conditioning, I take it?

Originally Posted by rx7dreamn1 (Post 9697822)

i have an auto now but am doing a swap i cant stand when people say "your cars nice but its an automatic "lol but i was gona keep it auto and upgrade as in the similar posts

Originally Posted by grimple1 (Post 9698600)

you could tell them that some of the fastest cars in the world are automatics or semi-automatics but I'm sure they wouldn't understand.

Originally Posted by 1Revvin7 (Post 9610292)

I think its time for a scatter shield...

https://www.rx7club.com/showthread.php?t=872321

Originally Posted by grimple1 (Post 9712572)

who made the shield amunoz? Did you change stalls?

Originally Posted by amunoz3 (Post 9883218)

488 whp the auto tranny is still running strong. :scratch:

Originally Posted by He's On Toroids (Post 9884043)

Good to know that the auto can hold that hp, let us know how many miles/runs you get on it. (might want to update that Sig now :) )

I am taking my 90K auto in for flushing and synthetic swap. Don't know if the transmission has ever been flushed before, I'm crossing my fingers that it won't hurt anything. Thoughts?

Originally Posted by tsmysak1 (Post 9437243)

94 Touring - Auto
Koyo, downpipe, everything else stock

Been off the forum for a while - largely because the 7 has been on stilts in the garage.

I am posting for the record. Perhaps this will help some others someday.


Built the engine back to stock because I wanted the auto trans to live a long life. Rumor is that a stock one is good for 350 HP. The one that came with the car lasterd about one year. I have no idea how many miles on it. Possibly over 100k. When it failed, it started to slip one morning. Limped it home and later swapped it out of a 30,000 mile stock tranny.

It felt and ran good, but also died shortly thereafter. Maybe 5000 miles at most. I am a moderate driver at best. I do not trash the car because I do not like laying under it. The second tranny made a horrible noise and did not go into gear, so I pulled it.

Bought a third tranny off the forum from a local. Supposedly is was a $4000 rebuild from Level 10 transmission. Supposedly new with a brand new stall convertor. I bit... got it cheap becasue the guy was doing a manual swap.

Put it in, the convertor was too thick and it damaged the front seal in the tranny. Leaked all over everywhere. I pulled it out, change the seal and smoothed up the welding flash on the convertor that cut the seal.

Tranny lasted about 200 miles. Towed it home.

I took all three trannys to A&A Transmission in Indy. These guys have a good rep with racing transmissions and one person there is a Jatco guru. Here is what I have learned.

The trannys are notorious for the pins walking out of the planetary gears. They have a high pressure issue at highway speeds (where I did most of my driving), and the material used in the stock convertors has a tendency to dissentigrate and wind up in the cooler or pan filter. In all three trannys, the pins were loose, includinig the low mile one. All three have convertor failure. It is possible that the previous failures left debris in the coolers, which exacerbated the failures of the following two. I blew the cooling system out each time, but that was not sufficient. You have to pull all coolers and hi-temp pressue clean (FYI).

All the trannys showed signs of slipping on the clutches and steels. The steels were burnt on the third gear.

I got a stall from a professional race builder in California. He replaced the suspect materials in the covertor clutch with high end materials and rebuilt it. Cost was around $480, which I think it was money well spent. Anyone looking at building up an auto probably should consider this as mandatory.

The planetary can be welded to hold the pins. I suggest doing this also to prevent higher mileage failures on your new expensive rebuild.

There are aftermarket shift kits that improve the high pressure issue with this tranny. This is not a concern for race cars (that are driven little), but is for cars that are going to be driven alot on the highway. The high pressure can damge the internals..I am noting this here, not as a expert but something that you should check out if you ever repair or rebuild one.

Also, stay away from Level 10. The internet has a ton of bad press on them and this tranny I had was built very poorly. The reliability improvements were not done and it looks like they reused too many old stock parts. Supposedly this was their high end rebuild. The pins in the planetary gears were about ready to walk out. Again, it lasted less than 200 miles....

One more thing. Make sure you buy a very high quality (OEM) filter. The aftermarket ones we found to have leaks around the seam. When we pressure tested, the filter sucked air... very bad...Also, all three trannys had the o-ring cut on the filter from improper installation. This is something that is a big concern. Whoever installs your filter needs to pay close attention not to damage the ring.


Cost was about $2350 for everything, tax included. I think the Mazda replacement was $2500, but no stall and standard components....I would not suggest going that route in light of the improments that need to happen.