3rd Gen General Discussion The place for non-technical discussion about 3rd Gen RX-7s or if there's no better place for your topic

AT-MT Swap - what harness to convert?

Old 02-15-19, 10:03 PM
Full Member
Thread Starter
iTrader: (8)
Join Date: Nov 2004
Location: somewhere
Posts: 68
Received 3 Likes on 3 Posts
AT-MT Swap - what harness to convert?

Acquired a automatic rx-7 and want to properly convert it to a 5 speed. I know many guys who have done the swap have used some of the automatic wiring to convert but I want to make everything look completely factory. In order to do this what harness would need to be changed besides the main engine harness?

The engine is already removed, the engine harness has been removed and the dash is out.
SpeedCrazie is offline  
Old 02-16-19, 12:00 AM
iTrader: (1)
Gen2n3's Avatar
Join Date: Jun 2004
Location: Virginia Beach, VA
Posts: 1,600
Received 150 Likes on 135 Posts

Congrats on your recent purchase! What threads have you already researched? Would you please cite them, where appropriate? That may help the subject matter experts. Have you looked at the WDM (Wiring Diagram Manual) for potential harness differences between AT and MT connectors? What ECU are you running - stock, PFC, or other? Further, what year is your FD?
Gen2n3 is offline  
Old 02-16-19, 12:39 AM
Full Member
Thread Starter
iTrader: (8)
Join Date: Nov 2004
Location: somewhere
Posts: 68
Received 3 Likes on 3 Posts
Hey George,

The RX-7 I am thinking of converting is a 1993 Touring.

I have scanned some past threads about the conversion. Most seem to jump harnesses and simply reuse the automatic engine harness. While I like the fact that this would be the cheaper and easier of routes I think I’d still like to come up with a shopping list of harnesses that would be needed to do this conversion in a OEM fashion.

From what I gather and I could be incorrect I would need:
Manual engine harness
Manual front harness the one that wraps around the engine bay
Manual dash harness?

Not sure if any of the interior firewall harness need to be swapped also.

SpeedCrazie is offline  
Old 02-16-19, 01:09 AM
Full Member
Blk 93's Avatar
Join Date: Dec 2006
Location: NW
Posts: 225
Received 10 Likes on 8 Posts
The biggest 5 spd + auto harness differences on the emissions harness (that you refer to as engine harness I think ) are the black connector to the auto ECU module which you would just leave disconnected, the white X-14 connector to the dash harness and blue X-05 connector to the front harness in your ECU footwell that hold more wires than 5 spd versions. If you don't want to modify your front and dash harnesses, you might be able to just swap to a 5 spd ECU, and convert auto trans connectors to 5 spd (two 2 pin male and one 4 pin male connectors) on the long branch that splits into 2 segments immediatly after the firewall on the engine side. The 2 pin female trans connector is the same on both auto + 5 spd.
It's a time consuming job figuring out the proper conversion pinouts. You need a 5 spd emissions harness and ohm meter, as a wiring guide, at a minimum.
If you want to make the car all "correct 5 spd", it will be costly and involved project. You would need a new/used dash harness , front harness, and emissions harness as you mentioned, in addition to the 5 spd ECU swap already mentioned. The front harness wraps around the engine bay from both ends of the firewall inside fender liners. I'm not sure you can install the dash harness without removing your dash. A few guys on the forum might be willing to mod your emissions harness transmission connectors for you if you're unfamiliar with wiring or connector swaps, or if you don't want to buy a 5 spd emissions harness as a guide for repinning your transmission connectors.
Good luck with your project !

Last edited by Blk 93; 02-16-19 at 01:24 AM.
Blk 93 is offline  
Related Topics
Thread Starter
Last Post
1st Generation Specific (1979-1985)
08-25-10 04:34 PM
2nd Generation Specific (1986-1992)
04-03-08 11:38 AM
Engine Management Forum
02-11-08 01:38 PM
2nd Generation Specific (1986-1992)
09-29-06 12:34 AM
2nd Generation Specific (1986-1992)
10-31-03 02:27 AM

Thread Tools
Search this Thread
Quick Reply: AT-MT Swap - what harness to convert?

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.