Porting in an auto 12a
#1
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Porting in an auto 12a
So I’m rebuilding my 12a and considering a street port or even possibly a half bridge BUT I have an auto transmission. Can that transmission handle the power? And are there any downsides?
#4
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there used to be places that modded the auto trans, Level 10 here in the USA, probably long dead.
its been done, but probably not in ~20 years
its been done, but probably not in ~20 years
#6
Slowly getting there...
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The "manual swap" would be you buying -
*Manual tranny for the same year range
*Lightweight steel flywheel (will mount to your existing counterweight) or used cast iron flywheel.
*New clutch kit
*Replacement pedal assembly w/clutch pedal
*New clutch Master and slave cylinders
*Manual shifter surround (easy to get new or used)
*Manual tranny for the same year range
*Lightweight steel flywheel (will mount to your existing counterweight) or used cast iron flywheel.
*New clutch kit
*Replacement pedal assembly w/clutch pedal
*New clutch Master and slave cylinders
*Manual shifter surround (easy to get new or used)
#7
Out In the Barn
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Nobody makes a kit for the auto to manual conversion. The ease of doing the swap depends on what year your RX-7. I would not put anything other then a stock port in an auto. The auto is a dog and can't even take advantage of the high revving rotary engine.
The 1979-1983 is pretty easy. Just need the comment stuff like trans/flywheel/clutch/master and slave hydraulics/hoses/clutch and brake peddle and hardware/etc.
The 1984-1985 require all the above plus welding in new trans cross-member body mounts. I've done this swap on my 1985 so I can offer some help.
The 1979-1983 is pretty easy. Just need the comment stuff like trans/flywheel/clutch/master and slave hydraulics/hoses/clutch and brake peddle and hardware/etc.
The 1984-1985 require all the above plus welding in new trans cross-member body mounts. I've done this swap on my 1985 so I can offer some help.
Last edited by KansasCityREPU; 03-21-21 at 09:19 AM.
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#8
Junior Member
Thread Starter
Nobody makes a kit for the auto to manual conversion. The ease of doing the swap depends on what year your RX-7. I would not put anything other then a stock port in an auto. The auto is a dog and can't even take advantage of the high revving rotary engine.
The 1979-1983 is pretty easy. Just need the comment stuff like trans/flywheel/clutch/master and slave hydraulics/hoses/clutch and brake peddle and hardware/etc.
The 1984-1985 require all the above plus welding in new trans cross-member body mounts. I've done this swap on my 1985 so I can offer some help.
The 1979-1983 is pretty easy. Just need the comment stuff like trans/flywheel/clutch/master and slave hydraulics/hoses/clutch and brake peddle and hardware/etc.
The 1984-1985 require all the above plus welding in new trans cross-member body mounts. I've done this swap on my 1985 so I can offer some help.
#9
Out In the Barn
iTrader: (9)
Handy thread: https://www.rx7club.com/1st-gen-gene...tions-1120671/
The first step is to gather all the parts.
1. 1984/1985 transmission with shifter
2. 225mm clutch/pressure plate/throw out bearing/pilot bearing
3. 1984/1985 clutch and brake pedal with long through bolt and it's spacers.
4. Clutch master/slave cylinders
5. 1984/1985 clutch master to slave hard line
6. Stainless steal slave hose.
7. Shifter dash plastic/boots
8. 1984/1986 manual trans cross member with bolts
9. Manual trans isolator
10. 1984/1985 Manual trans driveshaft. Might think about concerting the staked U-joints to replaceable ones. A good driveshaft shop can do this for about $120.
11. Trans body mounts from a 1984/1985 manual body. I have the ones in this pic I can sell after I remove them. Will require welding them to your body. I can get pics of what I did.
12. I'm sure I've missed something.
Here are some pics of what mine looked like after welding and before seam sealer/paint/undercoating. The ones with black wrinkle powder coating are the manual trans ones I added.
The first step is to gather all the parts.
1. 1984/1985 transmission with shifter
2. 225mm clutch/pressure plate/throw out bearing/pilot bearing
3. 1984/1985 clutch and brake pedal with long through bolt and it's spacers.
4. Clutch master/slave cylinders
5. 1984/1985 clutch master to slave hard line
6. Stainless steal slave hose.
7. Shifter dash plastic/boots
8. 1984/1986 manual trans cross member with bolts
9. Manual trans isolator
10. 1984/1985 Manual trans driveshaft. Might think about concerting the staked U-joints to replaceable ones. A good driveshaft shop can do this for about $120.
11. Trans body mounts from a 1984/1985 manual body. I have the ones in this pic I can sell after I remove them. Will require welding them to your body. I can get pics of what I did.
12. I'm sure I've missed something.
Here are some pics of what mine looked like after welding and before seam sealer/paint/undercoating. The ones with black wrinkle powder coating are the manual trans ones I added.
Last edited by KansasCityREPU; 03-21-21 at 12:34 PM.
#10
Senior Newbie Member
You need a modified auto trans with modded gear ratios to take full advantage. I have a modded auto trans, it revs higher before shifting ( 5.5 k ) and 1/2 gear is incredibly close together. The thing is my trans was modded back in the early 80's.and has cut gears that are noisier than stock.
As KCR said, , auto trans effectively strip your car of power by no allowing you to rip to 7, a neat trick is to put the car in 2 and drive it around like that. the car shifts at around 3.5 but will never shift to third gear and you will get to 7 K at around 60 mph . In 1 you will rip right to 6,5 at 40 mph, but letting go of the pedal slows you down bigtime.
Also, a common misconception many of you guys have is that the auto trans shifts at the same low RPM, wrong, it has a solenoid that detects how far your food is on the pedal, past halfway point you hear a click and the trans effectively delays its shifts up to 5.5k ( 5 k bone stock) . Also +1 it keeps your engine in better shape,
As KCR said, , auto trans effectively strip your car of power by no allowing you to rip to 7, a neat trick is to put the car in 2 and drive it around like that. the car shifts at around 3.5 but will never shift to third gear and you will get to 7 K at around 60 mph . In 1 you will rip right to 6,5 at 40 mph, but letting go of the pedal slows you down bigtime.
Also, a common misconception many of you guys have is that the auto trans shifts at the same low RPM, wrong, it has a solenoid that detects how far your food is on the pedal, past halfway point you hear a click and the trans effectively delays its shifts up to 5.5k ( 5 k bone stock) . Also +1 it keeps your engine in better shape,
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