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In your experience, what would the expansion of a 73 S engine from 2.4 to 2.8 liter mean in terms of horsepower and torque? (Stock specs 194 hp/154.0 ft lbs -correct me if I am wrong here) The car I purchased recently already has the 2.8 expansion done.
Thanks
Haasman
Depends on a ton of things. Compression ratio being the biggest followed by induction, heads, cam, etc. If done poorly, longevity is going to be an issue in the form of pulled head studs. If done correctly, a screaming car making 225 - 240HP?.
Chris
73 911 E
Chris- Totally agree with your concerns. I am awaiting the previous owner's paperwork to determine the quality of the conversion.
Any opinion on the engine's redline? Because of the larger displacement does that mean a more conservative upper RPM limit?
Haasman
RPM will depend on crank used and reciprocating mass of the pistons used and the connecting rods. Also will depend on the valve springs. So no easy answers. When I punched out my 865 Thruxton to a 1087, with new pistons, conn rods, crank, camshafts and shim under bucket valves, I also took the rpm from 7500 to 10,0000. So it really depends on the quality of what was done.
Oh yeah, and it whent from 63 to 110 rwhp ! So you can see its more than just the displacement increase that counts.
Ravi
If your car is matching numbers I would recommend building a second engine on a 7R case and putting your case on a shelf. This way you reserve the right to take the car back to stock in the future.Quote:
Originally Posted by Haasman
Just my $.02
Dave