912 engine into 356 a how to?
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- 356 Fan
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912 engine into 356 a how to?
Hi I'm installing a 67 912 engine in a 57 356t-1 using the original transmission. Any advice on what has to be done. Fly wheel? Clutch? Starter motor?
- Matthew Devereux
- 356 Fan
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Re: 912 engine into 356 a how to?
I just bought a 912 engine earlier this year for my 58. The flywheel won't fit and neither will most of the tin including the hard to find front and rear pieces. These are hard to come by and not cheap. The repro rear tin doesn't fit well. The front pulley tin needs to have holes drilled in it to clear the two large third piece bolts. I believe the clutch and starter should be fine. Is it 12 volt? I bought a 12 volt starter and flywheel that would work together from Zim's. The heat exchangers are different too so those will need to be replaced.
Matthew Devereux
'00 Boxster S
'58 356A coupe
'00 Boxster S
'58 356A coupe
- Greg Bryan
- 356 Fan
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Re: 912 engine into 356 a how to?
The 912 flywheel is larger, so a 356 flywheel must be installed. It also has the right number of teeth on the ring gear to engage the starter.
356 flywheels come with 2 sizes of clutches, 180mm and 200mm - not sure if a 912 clutch cover will fit on the 200m 356 flywheel - probably not.
All the perimeter tin is different but everything else is usable, including the heater boxes, although you will have to mess around with the hoses to make up for the different size connections
A kit is made to convert the 912 heater box actuators to 356 style - maybe Precision Matters makes them?
The 912 has a 12V generator so if you car is converted to 12V, you're ready to go - if not, you will need a 6V generator or convert the rest of the car to 12V - a somewhat expensive proposition to do correctly.
Same with the coil and the oil temp gauge sending unit may be a different calibration.
Throttle should hook right up to the bell crank behind the fan housing
Muffler tips are different
I'm sure there's more, but this is a start
356 flywheels come with 2 sizes of clutches, 180mm and 200mm - not sure if a 912 clutch cover will fit on the 200m 356 flywheel - probably not.
All the perimeter tin is different but everything else is usable, including the heater boxes, although you will have to mess around with the hoses to make up for the different size connections
A kit is made to convert the 912 heater box actuators to 356 style - maybe Precision Matters makes them?
The 912 has a 12V generator so if you car is converted to 12V, you're ready to go - if not, you will need a 6V generator or convert the rest of the car to 12V - a somewhat expensive proposition to do correctly.
Same with the coil and the oil temp gauge sending unit may be a different calibration.
Throttle should hook right up to the bell crank behind the fan housing
Muffler tips are different
I'm sure there's more, but this is a start
Greg Bryan
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- 356 Fan
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Re: 912 engine into 356 a how to?
Jordan-The 912 clutch cover will not fit in a 356 200mm flywheel. Curt
- Chris Markham
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Re: 912 engine into 356 a how to?
Harry Pellow's "ABCs and 912s" covers putting a 912 motor into a 356. A flywheel swap for an 180mm is a minimum or better, a 200mm C/SC flywheel to be able to use the larger clutch/pressure plate. With a 912 flywheel, which is larger in diameter you'd have to clearance the 716 transmission housing and swap the starter busing.. The ring gear of a 12V is different than 6V, so there's consideration of a 12V starter motor--which sends you down the road of a complete 12V conversion. With the changes involved (dynamically balancing a new flywheel on your 912 motor, you might consider a transmission swap from the 716 to a 741, which carries benefits and works with a 200mm flywheel with a C diaphragm pressure pate ("clutch cover"). Or, get a lightened C 200mm flywheel and have it balanced with your crank. A VW 200mm pressure plate won't work due to the flywheel depth difference between a 356 and VW. A Carrera 200mm pressure plate will work. But good luck with that. Oh, and don't use the late 912 rubber center clutch disc.
Hope this helps.
Hope this helps.
Chris M
59 Coupe #106728
'61 "Heinz 57" 1720. Stacks, ceramic headers, Supertrapp, Pertronix, Maestro 24k gold-plate coil strap for speed. Willhoit bar, Skirmants spring. 5" Brazilians. 20' paint w/abundant bubbles, GT straps, grilles.
59 Coupe #106728
'61 "Heinz 57" 1720. Stacks, ceramic headers, Supertrapp, Pertronix, Maestro 24k gold-plate coil strap for speed. Willhoit bar, Skirmants spring. 5" Brazilians. 20' paint w/abundant bubbles, GT straps, grilles.
- marcsherriff
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Re: 912 engine into 356 a how to?
Jordan,
Duane Spencer's excellent book, 356 Performance handbook, covers everything you need to know, and more you didn't need to know, but will make the car better. Well worth the purchase for any 356 owner, regardless of model or motor.
Duane Spencer's excellent book, 356 Performance handbook, covers everything you need to know, and more you didn't need to know, but will make the car better. Well worth the purchase for any 356 owner, regardless of model or motor.
Marc Sherriff
Marc and Cars
www.youtube.com/c/marcandcars
Perth.
Western Australia.
Marc and Cars
www.youtube.com/c/marcandcars
Perth.
Western Australia.
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- 356 Fan
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Re: 912 engine into 356 a how to?
Hi everybody, new guy here. I'm working on a 1964 C outlaw. I'm installing a 912 motor with a 12 volt generator and am using a 741 transmission. My question is, can I step down the voltage from the 12 volt generator to 6 volts through a resistor so I don't have to change the rest of the car to 12 volt?
- GregVandenbussche
- 356 Fan
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Re: 912 engine into 356 a how to?
HI Joe,
Small diameter 6V generator are usually easier to find than 12V one (correct me if i'm wrong) so you might want to do an exchange with someone or sell yours.
Small diameter 6V generator are usually easier to find than 12V one (correct me if i'm wrong) so you might want to do an exchange with someone or sell yours.
Bt5 Super - used to be fjord green, was painted brass, then brown... sadness
- Tom Tate
- 356 Fan
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Re: Step down resistor
Joe,
Short answer is no. The step down resistor is a workable solution for a single function but think about all the 6v items in the car and the current that they would draw. Horns, wiper motor, every light bulb, horn/headlight relay, and radio. If you used a stepdown resistor between the generator and the fuse box it would generate enough heat to cook dinner. That doesn't answer the question of what to do with the voltage regulator. Sourcing a 6v generator, coil, and temp sender is starting to look like an easy solution. KTF
Short answer is no. The step down resistor is a workable solution for a single function but think about all the 6v items in the car and the current that they would draw. Horns, wiper motor, every light bulb, horn/headlight relay, and radio. If you used a stepdown resistor between the generator and the fuse box it would generate enough heat to cook dinner. That doesn't answer the question of what to do with the voltage regulator. Sourcing a 6v generator, coil, and temp sender is starting to look like an easy solution. KTF
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- 356 Fan
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Re: 912 engine into 356 a how to?
I'm running a 12V generator on a 6V car. No issues. All the electronics work fine.
Greg Spreeman
1965 356SC Coupe
1964 356C Coupe
2001 996 Cabriolet
Gone but not forgotten:
1970 914
1965 356C Sunroof Coupe
1989 911 Carerra
1965 356SC Coupe
1964 356C Coupe
2001 996 Cabriolet
Gone but not forgotten:
1970 914
1965 356C Sunroof Coupe
1989 911 Carerra
- Eric McKinley
- 356 Fan
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Re: 912 engine into 356 a how to?
I plan on placing a 912 engine into my 356C.
From reading the posts above, am I correct in saying that the 356 heat exchangers will not fit?
If this is correct, do I need 912 heat exchangers.
Would anyone have a picture of the correct ones I need.
From reading the posts above, am I correct in saying that the 356 heat exchangers will not fit?
If this is correct, do I need 912 heat exchangers.
Would anyone have a picture of the correct ones I need.
- John Brooks
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Re: 912 engine into 356 a how to?
Here is a link to the mod for your 912 boxes
viewtopic.php?f=6&t=30400&start=75
viewtopic.php?f=6&t=30400&start=75
John Brooks
62 Roadster
66 912
84 Cab
getting pushed around in porsches since 1965
62 Roadster
66 912
84 Cab
getting pushed around in porsches since 1965