Perfomance question on future 2.7 build
 

Hi Guys, Just bought a 1975 911S with a 2.7. I previously had a 951 with the Lindsey 300hp upgrades. I have always loved the look and "feel" of the 911, but am really missing the in your gut power of the 951!

I know that it is comparing apples to oranges, but here is my question, What is the easiest and least expensive way to rebuild my 2.7 to match the raw power of my old 951. I am not a rich guy, nor a technical genius, but willing to learn and get my hands dirty. I would enjoy the education an experience of building my own motor. Not above an engine swap if that is the best reccomendation, but sure would like to keep the 2.7. It seems to me that the 911 could match the 951 with a lot less than 300 hp (I am guessing). Is inexpensive an oxymoron for what I am wanting to do?

I hate to ask newbie questions, and have spent days searching the archives, and the internet, and have been unable to find a comparison of the two as a starting point.

http://forums.pelicanparts.com/uploa...1229275557.jpg

Hi,

You will not be able to match the power of your 951 using the 2.7 unless you spend well north of $25K, and you'll wind up with a peaky motor with little or no power below 5000 RPM.

2.7's can make anywhere from 200-250 HP, but its not particularly cheap to get good reliable performance from these engines.

I think your budget will determine what avenue you choose for improved performance,...:) :)

I am kind of in the same boat.
I am looking at having my 2.7 rebuilt soon. I have a mechanic, but have not asked him any particulars.
I mentioned to him, I would like to build the rs spec engine, he said O.K. I would need cams, pistons and carbs. The whole reason I am getting into this rebuild is because I want the PMOs.
My understanding is, it is silly to just put the carbs on a stock 2.7.

As I do more research I am wondering if I can just get my cams reground to early S profile. I also am wondering if I can have my cylinders honed or bored out and just have to buy pistons. Maybe 2.8 if my cylinders can be bored?
These are cost saving ideas and I don't know if they are possible or not.

I don't mind buying the PMOs, because that is what I really want.
I understand that I would need the different cams and pistons to make them work properly.

Can I do these things?

The engine was rebuilt at 130,000 with the original owner. I am the second owner and now the car has 130,000 on the rebuild.
I only put a few thousand miles on the car per year. No track, only weekend hotrod stuff.
It will probably be the last engine I have to put in this thing. I hope.

What do you guys think?

I would try to source a good 3.6 engine and do a conversion.

I have a 75 911s, 130,000 miles on original engine. Just had it rebuilt.
2.9L p&c
Web Cam 05-262
10.5-1 cr
Twin plugged
Electromotive Crank fire Ignition
SSI'S
PMO.S
Dansk two in two out
287hp
Most fun you can have
not cheap but well worth it.http://forums.pelicanparts.com/uploa...1230057542.jpg

Mark,

What PMO's did you use?

40mm Pmo's, They have a tendency to run very rich. Rocket like acceleration.

looks good, but I don't know if I can spend that much.

How much did it cost? Approximately.

Mark -
That's a cool engine, did you build it yourself? I've got a '77 2.7 that I'd love to do something similar to. WOuld you be willing to share some expense info?

Thanks,
Tom

Thanks for the nice comments, the engine was built by Rob King at S-Car-Go in San Rafael CA. Lots of internal mods done by Ollies in LA. Parts and Labor---------$40,000. What can I say?, While your in There.

There goes that idea.

My budget could only build a third of that engine.

I have about 7K in my 2.7L.....kinda hard to pin it down exactly as I just rebuilt again last winter. I do good shoppin'.:D......DIY, of course.
10.5:1 Mahles, Solex cams, 40mm Webers, single plug on race gas.
225-230 hp @ 6200 & 215ish ft/lbs between 3800-5000.
A nice tractable motor with no rocket science thrown in but a I did a couple things to get the torque where I wanted it. I was pleasently surprised by the dyno graph.

While nothing is cheap, I think a swap to a 3.0/3.2 would be your best bet $$ wise. Then sell your engine to recoup some costs.

Thanks for sharing your $$ investment - especially because it's such a substantial sum. It must have been a fun motor to put together and even more fun to drive!

Tom

Ollies has moved to Havasu City, Arizona :(