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Well the motor is done and delivered to Henry. The dyno does not lie. On the first power pull we had a bit of a flat spot on the big end you can see at 4600 to 5000. I changed the air correctors from 170's to 160's and instantly it cured the problem. We had about two full hours of run time setting the carbs and playing with things before I adjusted the valves and made the power pulls.

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OK it is really simple.

I bought Wayne Dempsy's (Pelican Parts owner) book "How To Rebuild and Modify Porsche 911 Engines 1965-1989. I read it cover to cover many times and I lurked and asked questions on the Pelican Parts, Early 911S, Rennsport, and other sites. It depends on what your looking for in the way of power and reliability. I was after something that would be good in the lower RPM ranges with plenty of torque. I did not want to have to twist the motor past 6,000 to go fast. I got what I wanted with max HP at 5,750 and max torque at 4,700. I started with a 115 k mile 1980 3.0 type 930/07 and here are the specs:

Stock cases using 24 new factory steel studs.
Stock oil pump
Original crank/micro polished
Original rods/checked for out of round and rebushed on the small end
Original 9.3:1 Mahle CIS pistons
Goetz original replacement rings
Original Mahle Nikasil Cylinders honed with a 600 grit BRM bottle brush hone
New Iwiss timing chains and all new chain ramps.
Carrera pressure fed timing chain tensioner upgrade
Heads redone with new valves, guides, springs
Intake ports enlarged to 37mm
Stock CIS distributor re-curved to allow for faster full advance to a max of 30 degerees.
Stock "964" profile grind on the original SC cams.
Weber 40mm carbs 34mm vents, 60 idles, 150 mains, 160 air correctors.
SSI heat exchangers and M&K Stainless sport muffler.

The motor is nothing special. The biggest change was the cam profile, exhaust and carbs v CIS injection.
Dave, that book is a good one. Also Bruce Anderson's 911 book is good for the earlier cars. I am in process of building up a potent mill myself.

7R mag case, shuffle pinned, time-certed, and boat-tailed mains, oil pump mod, all done by Ollies Machine.
Original NOS 2.7l Mahle Nicasil cylinders, moon cut by Ollies.
JE pistons, 10.5:1 CR
OE crank, polished
Rebuilt OE rods
Dual plug heads, port-matched to intake/throttle bodies
Rebuilt MFI throttle bodies, bored to RS spec
Rebuilt MFI pump, "S" space-cam
Webcam S cams
Bosch recurved dizzy with machined alu top for 12 port cap and rotor by Jerry Woods
New oil cooler
Carrera pressure-fed chain tensioners

There is more, but that's all I can remember. Should end up being 250 hp plus. Original RS were 210 hp on 8.5:1 compression and single plugs. RSR was 2.8, high compression, dual plugs and 308 hp. Should be a nice revver with decent torque due to the very high compression and MFI. This will be coupled to a later year 915 trans in a 1972 T coupe. "Outlaw" badge on the back, SC rear steel flares, and definitely a ducktail. On the front, stock fenders, probably glass, and RS front spoiler. Bilsteins all around, lowered nicely, stock swaybars, larger torsion bars F-R for higher spring rate. 4 pot Brembos all around with drilled/vented rotors. Boxster leather seats and minimal interior in black. Bahia Red original color, black Carrera script decals. And of course 15" Fuchs in 7" and 8", refinished at Wheel Enhancement.

I need to buy bearings, seals, and sealants. Then I can start building this bad boy ;-)
Danny,

Looks fun but all that extra work and money for not much more HP than I came out with. Good thing you have a bigger wallet than me........;-).

Its all about if you want something to twist to 7,000+ to get the 250+Hp v my 237Hp at 5750.

Have you found out about the Turbo oil restrictors for the cams? Good cheap way to limit the oil to the cams and keep it from foaming.
Not really extra money. I bought the whole car as an unfinished basket case from a friend's brother. My friend passed from cancer in 2007, so I am finishing his dream. The way I look at it is I get the honor of completing it for him. Believe me, the price was not large, but it was fair.

I hear what you are saying about all the cash spent on these mods, but I didn't have to spend it. Realistically what do you think the red line is for this motor? I suppose I should ask that on Pelican.

BTW, I had a ride in Howard's IM-6, and loved it. Can't wait to see yours completed.

I think I already have the restrictors, but if not I will buy them. I had heard about them, but my brain is a sieve, so I wrote it down!
Danny,

My feeling is you will have a motor that will build max Hp in the 6500 to 7000 range. Its the "S" cams they need the RPM's to pull in the air. That is why I stuck with the "964" profile because I was looking for more torque on the lower end.

What port size is your intake/exhaust?
Thanks Dave. Screw you Danny ;).

I have both of Waynes book enroute as we speak. I'm still debating the 964 cams but definitely the SSI's and an M&K of some type. I really like the GT3 style.

I'm going with the "diet" approach for mine. As much as I can strip off that car without making it too "uncivilized" is, or has, already come off.

Dave,
What issue did you have with the cam grind? Did you use your stock cams and have them redone? How much hp/trq do you think it will it cost me to stay with the CIS?

Danny,
Your engine is soooo far out of my league I feel inadequate just typing here.
Dave, I went down and measured some things. Ports look to be 36mm both intake and exhaust. Same size on the throttle bodies. Intake/exhaust valves are 45 and 40mm. I don't have my exhaust yet, but I was thinking of SSI and a stock muffler modded to dual outlet. I do have a Bursch exhaust but they are pretty loud, so maybe not. I think you are right on the powerband, but since my CR is so high and with the dual plugs it should do a lot to bring the torque band down some. I do know the real RS had a 10K tach, and I think redline was around 8500. I don't think stock rods are good for that high though, so 7000-7500 seems alright. I figure I'll put it together the way my friend specified. Then, if I don't like it I can always change the cams to something more torquey.

Mickey, I take it you got my message on the other side ;-) Believe me, I don't think I'd even own a 911 unless this particular set of circumstances happened the way it did. It just seems like it was meant to be. There is nothing wrong with a stock rebuild, dude, they are expensive enough no matter what you do.
Mickey,

If you have stock SC cams the 964 grind works perfect on a SC cores. The 964 grind works well. The CIS was made for US emissions as much as anything. You will likely leave 25 to 30 Hp on the table v carbs but 964 (higher lift) cams work well to upgrade a stock CIS motor. Check this site out: http://www.drcamshafts.com/ this guy is in my back yard and I was able to drop off and pick up my stuff. You can go blind looking at the cam profile charts.......

Danny,

I would go for the SSI's and M&K if you budget allows. M&K males a version I used which has twice pipes coming out together like the GT-3 cars. That's the one I used with the "Polished Tips". They turned golden from the heat on the dyno power pulls. First you save a bunch of weight and second it sounds soooo sweeeet.....;-) Super quality parts!
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