Speedometer cable rt angle adapter suggestions??

[rx7locost]

I guess this is the right catagory. For background, my build is using the RX-7 running gear and instruments. The OEM system uses a mechanical cable from the trans to the speedometer. I dug out my speedometer cable just to see where it will run. Well, it is bad news. It runs right into the tunnel wall. I really don't want to run a cable under my feet. I think the solution may be to find a 1:1 right-angle adapter. Perhaps this is a similar problem with the Miata builds as well. How did you guys run your cables?

I have seen these adapters for GM vehicles and MGB's. I don't know if the threads are the same. Anybody know of a part from another donor that would fit?

[weconway]

I just purchased a second generation Miata ('99-'05) electronic speedo sender. No cables at all, and it plugs into a first gen Miata transmission. The ratios won't match, but nearly every aftermarket speedo can be adjusted to give a correct speed.

I know the Miata and the RX-7 share a lot of common geometry. Perhaps it would fit?

[Miatav8,MstrASE,A&P,F]

I had to hunt for this one. It should be added to the suppliers list.

http://www.texasindustrialelectric.com/speedo.asp

[RWHARTMANN]

rx7locost, I used my stock speedo cable. It has a pretty sharp bend at the trany tunnel and it seems to be working fine.

[rx7locost]

Miata and the RX-7 share a lot of common geometry. Perhaps it would fit

I need to drive the original mechanical speedo from the RX7. I was hoping that the RX and Miata tranny fittings were the same design and somebody had found a rt angle adapter for the Miata. Nothing like stealing good ideas from somebody else.

I had to hunt for this one. It should be added to the suppliers list

The TexasIndustrial link you mention shows the opposite end adapter. It will not work at the tranny end, nor would it fit the clip-on fitting of the RX7 speedo. I was hoping to not have to buy a new ( read $$) adapter, but find one from a junkyard that would fit.

It has a pretty sharp bend at the trany tunnel and it seems to be working fine.

Ralph, I'll have to check again but it seemed that it would be a VERY tight bend in my car. I looked at your build site but didn't see any pics. Can you post one or two showing the tight routing in the tunnel area?

Thanks for the ideas guys. Kepp 'em comming.

[RWHARTMANN]

Chuck, I get some pics of it this weekend.

Ralph

[dhempy]

I'm going to have the same problem. I think I'm going to run my cable into the passenger foot area. It's been a while since I considered it, so I don't recall specifics, but at the time it struck me that it would be only a minor intrusion, and not too difficult to adequately protect.

If this doesn't pan out for me, I'll look into an aftermarket speedometer with and electric pickup of some sort...but probably just put that money into a GPS solution and to heck with an rpm-based speedometer.

FWIW, Chet set his up with an abrupt bend to keep it in the tunnel. He said it lasted a very small number of miles before breaking the cable.

-dave

[Miatav8,MstrASE,A&P,F]

Miata and the RX-7 share a lot of common geometry. Perhaps it would fit

I need to drive the original mechanical speedo from the RX7. I was hoping that the RX and Miata tranny fittings were the same design and somebody had found a rt angle adapter for the Miata. Nothing like stealing good ideas from somebody else.

I had to hunt for this one. It should be added to the suppliers list

The TexasIndustrial link you mention shows the opposite end adapter. It will not work at the tranny end, nor would it fit the clip-on fitting of the RX7 speedo. I was hoping to not have to buy a new ( read $$) adapter, but find one from a junkyard that would fit.

It has a pretty sharp bend at the trany tunnel and it seems to be working fine.

Ralph, I'll have to check again but it seemed that it would be a VERY tight bend in my car. I looked at your build site but didn't see any pics. Can you post one or two showing the tight routing in the tunnel area?

Thanks for the ideas guys. Kepp 'em comming.

The link was for having them make what you need, not the part shown. Scroll to the bottom of this page for rx7 and miata speedo gear interchange:
http://www.solomiata.com/Drivetrain.html

Just use large grommets. If you don’t want to spend $15 for 25 grommets, the miata uses a large grommet that could work, due to the steep angle where it goes into the firewall. The hole isn’t round and there is a plastic cage built into the grommet. A few addel clamps can secure the cable to the inside corner of the passenger compartment. It shouldn’t look bad at all; just maximize the radius between the trans and the floor pan.

http://www.clipsandfasteners.com/Gromme ... _s/103.htm

[blownmiata91]

you probably have a solution already.
FYI, second generation Supra (82-early 86) w58 transmission has an L shaped speedo drive coming off of the transmission. Might fit????

[Tailwind]

This reply is a bit late on this thread, but for what it's worth, I am using a VDO speedometer with an inductive pick-up on the left front wheel. It has worked superbly and can be programed to indicate the correct speed.

This replaced an inaccurate mechanical speedometer set-up. I programmed it to match the speed shown by my GPS and couldn't be happier with it.

Bill

[oldejack]

http://www.speedograph-richfield.com/html/minature_gearbox.html has one for the Type 9, i don't know if they have one for a Mazda but;

With over 100 types available there should be one to suit your needs.

[Tim Taylor]

http://www.speedograph-richfield.com/html/minature_gearbox.html has one for the Type 9, i don't know if they have one for a Mazda but;

I called them when I was looking for the same for my Type 9. After shipping I could buy both the VDO speedo and inductive pickup. I also liked the look of the VDO gauges better than the stock cluster. In my opinion using the stock gauges makes the dash look more kit car than race car

[redbull]

I am about to address this tight fit as well and wanted to install a 90 degree gear that also has a “correction” to mate the Auto Meter (mechanical) speedometer. Turns out this is a nearly imposable effort since tyre diameter and final drive (4:10) is anything but stock from Mazda. I may switch over to electrical, but I’d like to install a 90 degree gear, with 1:1 ratio that I can add a inductive pick-up so I can use both mechanical (now) and electrical (later). Ya, leave it to me to make things more complicated. I will likely end-up using my GPS and just pretending the Mechanical Speedometer is working.
I think I can use this specification for the mechanical drive cable:
THIS CABLE HAS A 7/8" NUT ON THE TRANSMISSION END AND A 5/8" NUT ON THE SPEEDOMETER HEAD END. MOST SPEEDOMETER HEADS HAVE A 5/8"X18 THREAD ON THEM SUCH AS AUTO-METER
THE TRANSMISSION END IS 7/8"X18THREAD WHICH IS VERY WIDELY USED ON GENERAL MOTORS SUCH AS POWERGLIDE , TH-350 , TH-400 , TH-200 , TH-200R4 , 700R4 , 4L60 AND CHRYSLER TRANSMISIONS 727 AND 904 FOR EXAMPLE
Now I need to see that fits the Mazda Type 2 (M) transmission speedo drive… anyone know?

[kill no cone]

Redbull,
You may have many more options from Mazda that could work. Mazda has run everything from 3.73 to 4.62 as stock gearing. I believe finding a stock unit which will work is do-able.

I will let you know more details when I have it figured out (I have the same issue myself).

[redbull]

Redbull,
You may have many more options from Mazda that could work. Mazda has run everything from 3.73 to 4.62 as stock gearing. I believe finding a stock unit which will work is do-able.

I will let you know more details when I have it figured out (I have the same issue myself).

I think you are referring to the final drive ratio... right? I replaced my Miata 1.6L "open" rear with a Miata 1.8L TORSEN that has 4:10 ratio. My "designed" total wheel height is 23" (Top to bottom), and according to what I have read, (and I will soon verify by removing and inspecting), I should have a 22 tooth speedo drive gear (green) OEM North America Type 2 (M) transmission from a 1985 RX-7 non-turbo.

I need to verify that the transmission speedometer coupling is indeed a 7/8" x 15 but I have a sneaking suspicion it is going to be metric! Anyone? Buler?

All these little details really add up, Perhaps it is easier to install the mechanical now, and replace it later (if needed) with an indiction - electric speedomenter but heck I could install a dash mounted GPS for the same cost! Hum, now that seem slike a good idea? Anyone done this?