3.0 SC engine conversion for earlier 911
 

Does anyone know what modifications (if any) are necessary to use a 3.0 litre SC engine in a pre-1978 911? Does anyone know of a car with this mod? Is it worth it?

I'm about to do this conversion and would also appreciate hearing responses in this area. In my case, I have a 1983 Euro SC motor that I am planning to put into a '71 911. That motor is too much for the 901 tranny, so I will mate it to a 915 and go from there.

You say that the 3.0 is too much for a 901 transaxle....well there are countless 914 conversions out there with 3.0, 3.2, 3.6 and 350 Chevy motors using the 901 transaxle. It can realistically handle uo to 300 HP.

Last time I checked a 3.0 was rated at about 180-200 HP, right? So unless the 901 got a lot stronger when they put it in the lowly 914 then I think that converting to the 915 is a waste of money...now YOU DO have to convert the flywheel to an early style, but I don't see that as a big deal.

Just my $.02, BTDT and got the tee shirt too prove it...

Michael
914/6, 3.0

If the 915 can handle in excess of 300hp why did they put the 4 speed in the 930s?

Don't know...why don't we dig up Ferry Porsche and ask him....8^)

One reason may be that Porsche supposedly insisted that the transaxle be capable of handling at least DOUBLE the power of the engine that it was attached to.

Brian

I have absolutely no doubt that Porsche's transmissions are very strong. Their endurance racing record proves that. But getting back to my original question, has anyone ever put a 3.0 litre SC engine in an earlier 911? Someone mentioned changing the flywheel to one from an ealier engine. Is that the sole modification required?

I think the changes in flywheels deal with the two types of clutches used. Up to around 1970, a push style clutch was used, where 1970 and later used a pull style. The 70 and 71 901 transmisions have a really unique pull mechanism that was changed when they updated to the 915 transmission. I think the same flywheel was used from 70 to 77, but I don't know about how close it is to a 3.0 l.

I think you should pass on the upgrade and buy my 86' 911 Cab so I can get a newer one. Then we both win!

Huey58

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My 79 3.0 that is mated to a 901 trans needed an early flywheel...that was it. Been there for two years now...no problems...except for others that think there is a 2.0 under the deck lid...^)

I can imagine the looks on their faces as you vanish in a cloud of tire smoke. That car must be a little rocketship.

Well, I guess i kind of killed this conversation. I'm really good at that. Thanks everyone for your input, and good luck jmcjunkin with your conversion. Be sure to post some news here on how it's going, and any other gems of wisdom you uncover along the way.

Mike, what year is your 901, and is it in a 911 or 914? The 914 never used the pull type clutch. Tim

My 3.0 and 901 trans is in a 914/6. I converted the stock 3.0 double disc flywheel over the early 911/914 style flywheel.

I'm actually using the Kennedy 228mm Kevlar clutch disc (no springs) with their custom flywheel. They call a "nine inch" clutch assembly, but the disc is the same size as the VW busses...



[This message has been edited by mikez (edited 11-27-1999).]

I have a 72 911T, I decided to drop a 82 3.0 vs rebuilding my 2.4. I was told that the sc engines were reliable and it seems to be correct. My 72 had a 915 which was reccommended but manditory. I purchased it used with 61k mls. & have put approx 65k miles without any leaks or problems. It was a good move for my needs.

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yuen

Oh yeah, Regarding my last reply. I only had to do some rewiring but the rest of the upgrade bolted right in. No modifications were nessessary.

Kevin,

How does the 3.0l feel in your car? Is it much quicker than the heavier SC car? Would you have preferred to use a 2.4 build to E or S spec? Did you install an oil cooler up front?

Thanks,
Jamie

Jamie,

Sorry but no experience with the weight difference of the SC. It was a significant increase of HP compared to the 2.4 and I'm sure the wieght has a lot to do with it. I installed a front oil cooler changed bumpers (european bumper) and installed a custom dual exhaust system. This cut off a lot of weight. I still wanted reliability and thats why I did not modify the 2.4.
Good Luck.

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yuen

Jamie,

Sorry but no experience with the weight difference of the SC. It was a significant increase of HP compared to the 2.4 and I'm sure the wieght has a lot to do with it. I installed a front oil cooler changed bumpers (european bumper) and installed a custom dual exhaust system. This cut off a lot of weight. I still wanted reliability and thats why I did not modify the 2.4.
Good Luck.

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yuen