To rebuild tired 2.7 or upgrade to 3.0 or higher?
#1
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I have a 77 911 with a 2.7 thats leaking oil and has 137000 miles on the motor. So I decided to look into rebuilding the engine.
In the process of finding a rebuilder for this engine, some people made the suggestion to forget about the 2.7 and invest that money into a 3.0, 3.2,or even a 3.6 low mileage salvaged motor. I have been researching both options, to rebuild a tired 2.7 that has not had any upgrades except for a pop off valve in the air box. It still has the old style head bolts, the old style chain tensioners.
To up grade these and any other items and to rebuild this engine I will still just be left with a 2.7 with no performance upgrades at a cost of any where from $5000. to $9000. I should be able to pick up a 3.0 for around $4500. Or a 3.4 for around $5000. If I do decided to replace this motor with a larger one will every thing still connect together, i.e.915 tranny and clutch. Both of which was just recently rebuilt. Will the motor mounts line up.
Thanks again for all of the input.
77 911 S
2.7
<img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
In the process of finding a rebuilder for this engine, some people made the suggestion to forget about the 2.7 and invest that money into a 3.0, 3.2,or even a 3.6 low mileage salvaged motor. I have been researching both options, to rebuild a tired 2.7 that has not had any upgrades except for a pop off valve in the air box. It still has the old style head bolts, the old style chain tensioners.
To up grade these and any other items and to rebuild this engine I will still just be left with a 2.7 with no performance upgrades at a cost of any where from $5000. to $9000. I should be able to pick up a 3.0 for around $4500. Or a 3.4 for around $5000. If I do decided to replace this motor with a larger one will every thing still connect together, i.e.915 tranny and clutch. Both of which was just recently rebuilt. Will the motor mounts line up.
Thanks again for all of the input.
77 911 S
2.7
<img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
#2
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It depends! Hows that for an answer? A rebuilt 2.7 is nice, but not as as powerful as a 3.0, 3.2, 3.4, 3.6, 3.8, 3.3turbo etc where is the line going to be drawn, How much power/torque are you willing to pay for?
All of the above to one degree or another are interchangeable. When I put a 964 3.6 into my '76 I only needed a flywheel, some electric mods and minor mechanical mods(throttle linkage needs mods, fuel supply need mods, the rear crossmember needs a minor mod). Reusing the ssi exhaust and 915 trans(w/ a DME notch cut into it). The results are very satisfying.
Don't forget the the engine isn't the only mod that may be needed( I was starting w/ a well prepped Carrera 3.0). The more powerful the engine the bigger the oil coolers that are needed. A narrow car may need flares for biger wheels/tires as well. How about brakes? Suspension? One should always update the other systems of the car so that the capabilities of all of the components match.
All of the above to one degree or another are interchangeable. When I put a 964 3.6 into my '76 I only needed a flywheel, some electric mods and minor mechanical mods(throttle linkage needs mods, fuel supply need mods, the rear crossmember needs a minor mod). Reusing the ssi exhaust and 915 trans(w/ a DME notch cut into it). The results are very satisfying.
Don't forget the the engine isn't the only mod that may be needed( I was starting w/ a well prepped Carrera 3.0). The more powerful the engine the bigger the oil coolers that are needed. A narrow car may need flares for biger wheels/tires as well. How about brakes? Suspension? One should always update the other systems of the car so that the capabilities of all of the components match.
#4
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Weight balance will change with a big motor. We seem to built a lot of 3.0 motors for early cars since they can get into most race groups competivly. We make lots of power with a well built 3.0.
#5
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The weight difference between a 3 liter and a 3.6 liter is ~40#(per little Tech Spec books). Remove the ac and there is no difference. There are quite a few of these things running around now. Some owners do suspension work some don't but its certainly not a necessity. Haven't a clue about the weight of a 2.7 though.
Most often people will stick w/ a displacement because of class rules. If you don't race the torque of the bigger motors in a lighter car makes them a lot of fun. <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />
I've been driving around w/ a 964 in the back of my Carrera since '94. The combination is a blast and very reliable to boot.
Most often people will stick w/ a displacement because of class rules. If you don't race the torque of the bigger motors in a lighter car makes them a lot of fun. <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />
I've been driving around w/ a 964 in the back of my Carrera since '94. The combination is a blast and very reliable to boot.
#6
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The 3.6 may be bigger displacement wise but the block is pretty much the same as all previous al. cases, the difference being the 3.6 had its studs moved radially out from the bore centers.
Its not like the difference between a big/small block Chevy.
Its not like the difference between a big/small block Chevy.