3.2l Corvair Engine Build, preliminary ideas and questions |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
3.2l Corvair Engine Build, preliminary ideas and questions |
macnichol |
Aug 6 2020, 11:11 PM
Post
#1
|
Newbie Group: Members Posts: 40 Joined: 12-June 20 From: Indianapolis, IN Member No.: 24,372 Region Association: NineFourteenerVille |
As I've done more and more research on potential engine swaps for my car, I've come across some people swapping the Corvair flat 6 into their cars. I really like this option, as it keeps the aircooled spirit of these cars, engines are quite inexpensive to get to 200+hp compared to a conventional 911 Flat 6. These engines rotate backwards so I need to come up with probably a new way of reversing the rotation, since I quite like the 901 gearbox. I think for now I just want to aim for 200hp at the wheels, even though I know these engines are capable of much, much more. My plan is so far is to get a good example of an engine, swap in 94mm Mahles and 911 bits and stroke it a small amount to 3.2l. I think this will be a good balance between a few things, I want to stay away from boring stuff out in the interest of long term reliability. I plan on fabbing up a 911ish-style fan shroud as the stock cooling of the Corvair was not designed with our mid-engine setup in mind and I can foresee cooling issues, especially with a larger displacement engine. For those of you who build your own engines and maybe the king Mr. Raby himself, how reliable are aftermarket nikasil coatings and cryo treatments? I may build a few of these "hybrid" engines if there is enough interest in a powerful alternative to 911 and Raby engines, I feel like many people have been priced out of that market, not due to anyone's fault. I've done some digging over at the corvair forums, it's not uncommon for people to get ~300hp and 100k miles out of these motors before rebuild, as long as proper cooling is done and maintenance is looked after. What do you guys think?
|
sixnotfour |
Aug 7 2020, 02:57 AM
Post
#2
|
914 Wizard Group: Members Posts: 10,433 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains |
There is guy with great engine for sale..hopefully he is still with Us..search R3dplanet ..Marcus
here is the link,, http://www.914world.com/bbs2/index.php?sho...=341485&hl= BTW youre over thinking it...flat fan ..good ...vw PCs cheep .BTW flip the ring gear....or buy a 3.2 Porsche engine.. I had a Turbo Corvair in High School...$300 |
mb911 |
Aug 7 2020, 04:42 AM
Post
#3
|
914 Guru Group: Members Posts: 6,871 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
I never got this swap.. I think personally if I were doing any swap it would be beside the porsche 6 it would be a suby swap.. Yes folks a water pumper.
|
DRPHIL914 |
Aug 7 2020, 05:42 AM
Post
#4
|
Dr. Phil Group: Members Posts: 5,768 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
There is guy with great engine for sale..hopefully he is still with Us..search R3dplanet ..Marcus here is the link,, http://www.914world.com/bbs2/index.php?sho...=341485&hl= BTW youre over thinking it...flat fan ..good ...vw PCs cheep .BTW flip the ring gear....or buy a 3.2 Porsche engine.. I had a Turbo Corvair in High School...$300 shows he was last active July 31, 2020 so i'd say he is here, not sure if he completed and sold the motor, but from what i remember he was close to completion and it was for sale due to health reasons, Maybe he will see this and chime in .. hey marcus!! @R3dplanet |
mepstein |
Aug 7 2020, 06:41 AM
Post
#5
|
914-6 GT in waiting Group: Members Posts: 19,305 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
I never got this swap.. I think personally if I were doing any swap it would be beside the porsche 6 it would be a suby swap.. Yes folks a water pumper. Me either. Back in the day, Corvair engines were cheap but so were Porsche engines, so no reason to go Corvair. Now, Corvair engines are pretty pricey and require a lot of mods to make it all work. Might as well modify a type 4 since that path is well proven or use a Porsche engine, costly but still a bolt in conversion. Or like Ben said, a suby engine if you want 100K reliability. It does seem strange that your in the “research” phase with lots of unanswered questions but already thinking of building and offering engines for sale. |
Cairo94507 |
Aug 7 2020, 08:33 AM
Post
#6
|
Michael Group: Members Posts: 9,808 Joined: 1-November 08 From: Auburn, CA Member No.: 9,712 Region Association: Northern California |
I agree with Ben and Mark. If I were to build another 914, it would be GT flared with a 300 HP Subaru motor and a Boxster 6 speed. (IMG:style_emoticons/default/beerchug.gif)
|
DRPHIL914 |
Aug 7 2020, 12:24 PM
Post
#7
|
Dr. Phil Group: Members Posts: 5,768 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
I agree with Ben and Mark. If I were to build another 914, it would be GT flared with a 300 HP Subaru motor and a Boxster 6 speed. (IMG:style_emoticons/default/beerchug.gif) i would not ... you want a water pumper? get a 986,987 or 996.......... i would buy that 6 speed trans though.. attached to a 290h 3.4l porsche 6 in either a Cayman S or boxster. I have a nice quick nimble 914 and love it for what it is, i have had 2 boxsters and at some point i will get one of those, probably a Cayman as you can get them for under $20k, or about the same price or less than the cost of converting your 914..... |
macnichol |
Aug 7 2020, 05:32 PM
Post
#8
|
Newbie Group: Members Posts: 40 Joined: 12-June 20 From: Indianapolis, IN Member No.: 24,372 Region Association: NineFourteenerVille |
I agree with Ben and Mark. If I were to build another 914, it would be GT flared with a 300 HP Subaru motor and a Boxster 6 speed. (IMG:style_emoticons/default/beerchug.gif) i would not ... you want a water pumper? get a 986,987 or 996.......... i would buy that 6 speed trans though.. attached to a 290h 3.4l porsche 6 in either a Cayman S or boxster. I have a nice quick nimble 914 and love it for what it is, i have had 2 boxsters and at some point i will get one of those, probably a Cayman as you can get them for under $20k, or about the same price or less than the cost of converting your 914..... Yeah, I refuse to do any sort of water cooled swap on my car, just doesn't fit the style of these cars. Plus makes it more difficult to return to stock and the additional weight of a water jacket and cooling lines and radiator is not something I'm keen on. The simplicity of an aircooled motor is what I am after, with decent 200hp power as well, I think that will be plenty in such a light car. |
sixnotfour |
Aug 7 2020, 08:03 PM
Post
#9
|
914 Wizard Group: Members Posts: 10,433 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains |
I agree with Ben and Mark. If I were to build another 914, it would be GT flared with a 300 HP Subaru motor and a Boxster 6 speed. (IMG:style_emoticons/default/beerchug.gif) i would not ... you want a water pumper? get a 986,987 or 996.......... i would buy that 6 speed trans though.. attached to a 290h 3.4l porsche 6 in either a Cayman S or boxster. I have a nice quick nimble 914 and love it for what it is, i have had 2 boxsters and at some point i will get one of those, probably a Cayman as you can get them for under $20k, or about the same price or less than the cost of converting your 914..... Yeah, I refuse to do any sort of water cooled swap on my car, just doesn't fit the style of these cars. Plus makes it more difficult to return to stock and the additional weight of a water jacket and cooling lines and radiator is not something I'm keen on. The simplicity of an aircooled motor is what I am after, with decent 200hp power as well, I think that will be plenty in such a light car. 2.4 S ish 911 engine.....favorite for peeps for ever....Don't get me wrong I was 3rd out of 26 in autocross at 16 yr old..turbo corvair ..just not as stout as the Porsche Design.. My buddy wants to sell a spare vintage racing 2.2 fresh with webers 10 k..never fired.. dry sump revs higher lasts longer..your corvair will drop a seat ..heads are junk |
r3dplanet |
Sep 4 2020, 11:14 PM
Post
#10
|
Senior Member Group: Members Posts: 679 Joined: 3-September 05 From: Portland, Oregon Member No.: 4,741 Region Association: None |
Ahoy mateys -
I'm still breathing. I know that the Corvair swap isn't for everyone. But it was right for me and I didn't bother to get any input other than from those who already had done the swap. My goals were (relatively) cheap, didn't want to adjust valves anymore, 3.0 liters of power, good driveability, ability to use stock gearbox, not water cooled because I didn't want to cut up the car. These engine really are very solid and I reasoned the swap is a fine way to go. Not the most modern swap, but certainly very analog and I think that fits the 914 ethos. The downsides that I learned along the way were that so much relies on specialty machining that was once common among the Corvair enthusiast crowd, but with the passage of time most of the best of those guys have retired and moved on. There's still a couple of good guys out there doing great work and I mentioned them in my thread. However, once all the oddball pieces are assembled and the engine built up it will run very well for a long time with basic maintenance. A rebuild down the road is no more difficult than any other air cooled build, especially given the VW pistons and cylinders. For example, I wanted to use a set of Weber or Dellorto carbs and that required custom intake manifolds. They can be made but expect a long wait time while they're fabricated. Worth it for me but not if you're in a hurry. It's possible to save a lot of time and get 110 heads and buy an aftermarket ready-to-go EFI system that's popular with the gang. Lots of lessons learned along the way and honestly that's half the point. At this moment my engine is up for sale along with all the bits and tools that went along with it. That includes the conversion flywheel, intakes, modified alternator, the original pieces, all of it. Disregarding the money spent on machining and labor here and there I'm just trying break even on the parts and I'm willing to deal even on that. Seems fair to me. Any buyer should be prepared to remove the cylinders and split the cases because the engine doesn't rotate easily. I'm 99% sure that the second crankshaft I bought (hardened, forged) and installed has slightly too much meat on the case journals despite having it professionally cut and polished. That machinist and I had different ideas about how far down to bring them. The rod journals are certainly fine. I have another crankshaft (cast, but cryogenically treated) that I seem to remember is the better fit. I swapped them out at the last moment and that's likely the mistake I made. If I don't get a buyer in the next couple of months I'll just disassemble it and sell the components individually on eBay or something. I have to move into hospice at some point and I can't have all this stuff laying around. I'm much too weak to even begin to approach tearing it down again myself. Thanks for pinging me. It's nice to read up on what the gang is doing. -m. |
steuspeed |
Sep 5 2020, 02:50 AM
Post
#11
|
Senior Member Group: Members Posts: 1,008 Joined: 12-July 11 From: Portland, Oregon Member No.: 13,308 Region Association: Pacific Northwest |
My dad raced a turbo Corvair covertable. Freaking awful! turbo lag plus body flex.
|
sixnotfour |
Sep 5 2020, 04:36 AM
Post
#12
|
914 Wizard Group: Members Posts: 10,433 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains |
Ahoy mateys - I'm still breathing. I know that the Corvair swap isn't for everyone. But it was right for me and I didn't bother to get any input other than from those who already had done the swap. My goals were (relatively) cheap, didn't want to adjust valves anymore, 3.0 liters of power, good driveability, ability to use stock gearbox, not water cooled because I didn't want to cut up the car. These engine really are very solid and I reasoned the swap is a fine way to go. Not the most modern swap, but certainly very analog and I think that fits the 914 ethos. The downsides that I learned along the way were that so much relies on specialty machining that was once common among the Corvair enthusiast crowd, but with the passage of time most of the best of those guys have retired and moved on. There's still a couple of good guys out there doing great work and I mentioned them in my thread. However, once all the oddball pieces are assembled and the engine built up it will run very well for a long time with basic maintenance. A rebuild down the road is no more difficult than any other air cooled build, especially given the VW pistons and cylinders. For example, I wanted to use a set of Weber or Dellorto carbs and that required custom intake manifolds. They can be made but expect a long wait time while they're fabricated. Worth it for me but not if you're in a hurry. It's possible to save a lot of time and get 110 heads and buy an aftermarket ready-to-go EFI system that's popular with the gang. Lots of lessons learned along the way and honestly that's half the point. At this moment my engine is up for sale along with all the bits and tools that went along with it. That includes the conversion flywheel, intakes, modified alternator, the original pieces, all of it. Disregarding the money spent on machining and labor here and there I'm just trying break even on the parts and I'm willing to deal even on that. Seems fair to me. Any buyer should be prepared to remove the cylinders and split the cases because the engine doesn't rotate easily. I'm 99% sure that the second crankshaft I bought (hardened, forged) and installed has slightly too much meat on the case journals despite having it professionally cut and polished. That machinist and I had different ideas about how far down to bring them. The rod journals are certainly fine. I have another crankshaft (cast, but cryogenically treated) that I seem to remember is the better fit. I swapped them out at the last moment and that's likely the mistake I made. If I don't get a buyer in the next couple of months I'll just disassemble it and sell the components individually on eBay or something. I have to move into hospice at some point and I can't have all this stuff laying around. I'm much too weak to even begin to approach tearing it down again myself. Thanks for pinging me. It's nice to read up on what the gang is doing. -m. (IMG:style_emoticons/default/smilie_pokal.gif) (IMG:style_emoticons/default/smilie_pokal.gif) (IMG:style_emoticons/default/smilie_pokal.gif) @slow914 |
Dr Evil |
Sep 5 2020, 12:08 PM
Post
#13
|
Send me your transmission! Group: Members Posts: 23,002 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
I have a 3.1 vair plant in my bus. It’s coming out for an SVX swap. I almost did one in my 914, but a 2.7 Porsche 6 landed in my lap and I couldn’t say no. Reverse rotations then is easy with kit from Clark’s Corvair.
|
sixnotfour |
Sep 5 2020, 12:19 PM
Post
#14
|
914 Wizard Group: Members Posts: 10,433 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains |
QUOTE Reverse rotations then is easy with kit from Clark’s Corvair. why not flip the ring gear ?? |
gandalf_025 |
Sep 5 2020, 12:26 PM
Post
#15
|
Senior Member Group: Members Posts: 1,456 Joined: 25-June 09 From: North Shore, Massachusetts Member No.: 10,509 Region Association: North East States |
If you are building the engine anyway,
Backwards cam is easy.. also, if you ever decide to sell.. There is a bigger market if the engine matches up without having to tear a trans apart.. |
tazz9924 |
Sep 5 2020, 12:44 PM
Post
#16
|
Senior Member Group: Members Posts: 703 Joined: 31-May 15 From: Mooresville NC Member No.: 18,779 Region Association: None |
Could you just use a 911 transmission but use it mid-engine? my brain math tells me that would solve for the backwards rotation.
|
gandalf_025 |
Sep 5 2020, 12:51 PM
Post
#17
|
Senior Member Group: Members Posts: 1,456 Joined: 25-June 09 From: North Shore, Massachusetts Member No.: 10,509 Region Association: North East States |
Shift mechanism is an issue...
|
mepstein |
Sep 5 2020, 01:44 PM
Post
#18
|
914-6 GT in waiting Group: Members Posts: 19,305 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
Could you just use a 911 transmission but use it mid-engine? my brain math tells me that would solve for the backwards rotation. You would be applying an expensive solution to handle a simple problem. I’ve only been on world for 10 years. Has anyone actually completed a covariant into their 914? I haven’t seen one yet. |
sixnotfour |
Sep 5 2020, 02:28 PM
Post
#19
|
914 Wizard Group: Members Posts: 10,433 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains |
Could you just use a 911 transmission but use it mid-engine? my brain math tells me that would solve for the backwards rotation. You would be applying an expensive solution to handle a simple problem. I’ve only been on world for 10 years. Has anyone actually completed a covariant into their 914? I haven’t seen one yet. ive seen bugs and almost bought a 356 with one.. |
Dr Evil |
Sep 5 2020, 03:02 PM
Post
#20
|
Send me your transmission! Group: Members Posts: 23,002 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
For those saying flip the diff, no. The problem is that the INPUT rotation is backwards so all gears move in reverse and no matter what orientation you put the diff in, the thrust side will now be the coast side. This is not a good idea. It’s not hard to change direction I’m a corvair. It’s actually not very expensive, if you were splitting the case anyway. A stock vair engine can easily put out 140. Slight mods move that up. Big mods cost money and move it up a lot.
The 3.1 I have in my bus was intended for my 914. It’s been bored out, TIV 2.0 p/c machines to fit, and fancy heads done by one of the big names in corvair, Starr Cooke. You could bolt up Weber 3c carbs, but I’ve been using a 4bbl Edelbrock because it’s a mini van and not a sports car. My link below covers the Tranny bus saga for most of its life. The only reason I’m going water filled is heat and AC. Got tired of not having time to engineer a solution I liked. If going Corvair into 914, get reverse rotation kit to flip dizzy rotation, cam, alternator. Don’t listen to nay sayers. Just accomplish it. I’d personally buy Redplanets, but mine could be up for sale in the future if someone was interested since I’m swapping. |
Lo-Fi Version | Time is now: 31st May 2024 - 10:29 PM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |