ever heard about a 2.5 flat six? Options

[Gustl]

got some info on a '70 six for sale here in Austria
the owner told me, that it got a 2.5 engine installed in 1971 by the Porsche factory - now there's a 2.7 in

well, I've never heard about a 2.5 (IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif)
the seller told me, that is was a very special/rare engine, but it's gone for more than 20 yrs

now I wonder about that engine
does anyone know such an engine? what could you tell me about?
carbs or FI, power, torque, rpm bandwith ...
just try to describe this engine, please

many thanks in advance,
(IMG:http://www.914world.com/bbs2/html/emoticons/pray.gif) Gustl

[J P Stein]

QUOTE (ArtechnikA @ Apr 10 2005, 11:52 AM)

i have just such a case waiting in my garage for the 2,2's rebuild :-)

Nice. If I see one, I'll buy it just for the hell of it.

The S cams work great with MFI as the fuel reversion problems
don't happen as they do with carbs, but as I said, feel free.....
I learned some time back to neither over cam nor over carb an engine for it's intended use....the hard way, of course (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

[ArtechnikA]

i think that at first, i'll be running the 40mm Webers from the /6 on the 2,7/2,8 since they're paid for, and a set of RSR throttle bodies aren't :-)

since this engine is destined for the 911 (first) i have the additional option of running the tall manifolds, which will give me a little more room for match-porting too. that should help a bit.

[jfort]

I really like the 2.5 in my car. It is the for Jim Chambers car. shorter gears. lots of torque. strong shifts in all 5 gears, but not a highway cruiser.

[Eric_Shea]

Put some biga$$ balloon tires on it. It'll do great on the highway (IMG:http://www.914world.com/bbs2/html/emoticons/w00t.gif)

[Porsche Rescue]

Eric, now you know where I learned my lesson. A few years ago I bought the six shown below in San Jose, CA. Had a sport muffler (J. Fort has it now) and even shorter gears than his car. Drove it home in one day, 750 miles, required 4400 rpm to make 80 mph. Wish I had thought to stop and buy ear plugs!
Ida in fifth drives like a Lincoln Town Car (maybe not quite). Hand throttle at max is a fine cruise control, stays right at 70. WCC here I come.

[Porsche Rescue]

However, if I can find a set of Mahle gas burners at a reasonbable price, I may have an optional set of lower profile tires so as not to be subject to ridicule by you young'uns.
A set of Boxster 7x16's might also be nice.

[JoeSharp]

Soo... Jim . Whos car is that and what spacers did they use?
(IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) Joe

[Porsche Rescue]

Car belongs to "jim912928" from South Bend, IN.
There is a thread in the classified parts for sale "16 Boxster Wheels", near the bottom of first page. He talks about them there.

He started with 6's in rear and 7's in front but has changed to all 7's.
No spacers, stock fenders. Not even rolled if I recall. Best looking big-bumpered car I've seen.

[Eric_Shea]

***Official Thread Hijack***

Jim's my hero. It seems as though he's got Ida's oil issues sorted out. My friend, you are truly the next rightful owner. Thanks for taking good care of this car (IMG:http://www.914world.com/bbs2/html/emoticons/smilie_pokal.gif)

You can put whatever tires on her you want. (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)

Also, the other Jim in South Bend has one hell of a nice looking car. I met both (the car and the owner) at last years MWC.

Back on subject... I'm still gonna build my carb starv'n 2.5 and it will probably be sitting on that good for nothing, rickety, shitty-ass, balsa wood block. I promise to write the board when it scatters crank bearings all over the county and pulls all the head studs. You all can say "I told you so" then. (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif)

[HotRod]

Aren't the 7R cases magnesium?..and more flexible? Wouldn't you want an earlier aluminum case? I had a 7R case align bored and couldn't find the oversize main bearings for less than $800.

I redid a 2.7 a couple years ago and used an early (69 I think) aluminum case that I got from Bruce Jennings, with all the appropriate machining, the 2.7RS pistons, S heads C/R around 11.5:1 if I remember correctly, E-cam grind that is a little milder than the RSR grind, webers. I use this motor for endurance racing a 911.

[ArtechnikA]

QUOTE (HotRod @ Apr 11 2005, 12:04 PM)

Aren't the 7R cases magnesium?..and more flexible?

yes.

QUOTE

Wouldn't you want an earlier aluminum case?

tradeoff. by the time you've done everything you need to prep an aluminum case you might as well have started off with a 7R. if you have an aluminum case, it's not a bad place to start.

QUOTE

I had a 7R case align bored and couldn't find the oversize main bearings for less than $800.

i won't ask where; it's not important. donno why you'd spend money for machine work and expensive bearings when a low-time 7R could be had for a fraction of that. but it's your call, do what you want.

*next* time, tho, consider sending the case to Competition Engineering, where they can resize the case (just like resizing a rod...) and you'll wind up with a case that takes standard bearings and a '0' intermediate shaft gear. there's a limit to the magic they can work, because there are a few reasons you can't make a 911 case too narrow. buit new(er) cases are not hard to find...

QUOTE

I redid a 2.7 a couple years ago and used an early (69 I think) aluminum case that I got from Bruce Jennings, with all the appropriate machining, the 2.7RS pistons, S heads C/R around 11.5:1 if I remember correctly

did you use the standard or the Turbo piston squirters ?

QUOTE

E-cam grind that is a little milder than the RSR grind

an E cam is a LOT milder than an RSR!

QUOTE

I use this motor for endurance racing a 911.

24 hours? 12? where are there endurance race events for early 911's? love to get involved with that but i don't know of any events in my area...

[Eric_Shea]

QUOTE

I redid a 2.7 a couple years ago and used an early (69 I think) aluminum case that I got from Bruce Jennings, with all the appropriate machining, the 2.7RS pistons, S heads C/R around 11.5:1 if I remember correctly, E-cam grind that is a little milder than the RSR grind, webers. I use this motor for endurance racing a 911.

Sounds like a cool engine. From what I understand the big difference with the 7R vs. the Die-cast Aluminium would be the spigot base. 7R's had nice beefy spigot bases pressure cast into them. Makes for good increase mods. But hey, I'm just parroting what I've read in Bruce's book, like everyone else (IMG:http://www.914world.com/bbs2/html/emoticons/chatsmiley.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/lol3.gif)

[J P Stein]

"all the appropraite machining" is the key phrase here......to parrot Rich, who is parroting Anderson. Since some folks can't or won't read or don't believe what they read, someone has to do it. (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif)

And who better to parrot? I've spent a bit of time rootin' around in a few 9eleben motors and haven't found his info to be wrong....in stark contrast to the internet.

[Eric_Shea]

I didn't mention any names... (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/lol3.gif)

"baawwwwwk"

[HotRod]

It's been 10 years or so since I had this engine done, but yes I believe that it was the Turbo Piston squirters...

I don't mean the 911E cam, E-Cam is a company that had their own grinds for 911s, don't know if they're even still around.

6 hours, 12 hours, I usually do the SCCA endurances, there's a 12 hour at Summit Point, WV in June.

I didn't spend much on the aluminum case, it kinda fell in my lap already machined and ready to go. I'll look back in the paperwork and see what all's in this thing.

Yeah, I knew I could get a 7R cheap, but thought that the aluminum would be better for racing, just an assumption...just was wondering if anyone else had had the issue with bearing prices after getting align bored?

[ArtechnikA]

QUOTE (HotRod @ Apr 12 2005, 09:19 AM)

...just was wondering if anyone else had had the issue with bearing prices after getting align bored?

first, thanks for the information !

we just had this discussion over on RennList's 911 List. MOST of the time, the #8 main bearing (the expensive one) is just fine and can be re-used. even if the bearing is worn beyond service limits (which may mean it's opened up to the clearance you'd want in a race engine :-) ...) the bore in the case is probably just fine.

so - even if the case can use an align hone on the shell bearings (#1 through #7) it should be carefully miked to determine if anything needs to be done to #8. if not, leave it alone and save a lot of money. or - send the case to CE and have them resize it.

i recall a case (long time ago, so i won't mention the shop since i've heard the situation is different now...) of a well-known VW machine shop that was famous for line-boring cases to an oversize that just happened to match the bearings that they'd bought up all of a manufacturer's production. you do have to shop around and be an informed consumer...

[sixnotfour]

.25mm overbore main bearings with standard crank. are from 200-400 from the dealer depends on how the parts dept. reads it , They come in halves 2 to a box , So some Porsche dealers sell them for twice as much as others. The Ones that I know are redily available are for the late 2.7 Cases. The retaining tab is in a different location(more centered) earlier cases can be updated if need be.
The above does not include #8 bearing.

I know an old timer that has 200 sets of 1st over case ,1st under crank. ,said he got a good deal on them.
He still wants 250.00 a set, He will probably leave them to his Son.

2.7 based 2.5 is the most economical way to go.

[Eric_Shea]

QUOTE

got some info on a '70 six for sale here in Austria the owner told me, that it got a 2.5 engine installed in 1971 by the Porsche factory - now there's a 2.7 in

Is it green? Maybe it's the car in the video... (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)

[Gustl]

QUOTE (Eric_Shea @ Apr 12 2005, 09:46 PM)

QUOTE got some info on a '70 six for sale here in Austria the owner told me, that it got a 2.5 engine installed in 1971 by the Porsche factory - now there's a 2.7 in Is it green? Maybe it's the car in the video... (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)

what video are you talking about (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)

about the last 20 yrs it looked this way:

(IMG:http://www.porsche914.at/ausfahrt1309/DSCN1490_WEB.JPG)

last fall a friend of mine bought it and did "a little work" on it (roll cage, steel flares, new paint, completely engine rebuild) and just sold it to spain
first I was really interested, but it was "a little" too expensive for me (more than 38k EUR (IMG:http://www.914world.com/bbs2/html/emoticons/wacko.gif) )

[Gustl]

one more