Euro Conversion of a 1982 3.0 (US)

VFR750 · 11-25-2009, 12:12 PM

Background: My 1982 3.0 is getting a little tired. 119K miles and ~50 track days (est 65-70 hours) are taking their toll. Oil Consumption is not terrible on the street, but about 1qt per 100 miles on the track. A leak-down test says the rings are leaking more than the should, but not critical. I get a little puff of blue smoke on start up. The signs point to a rebuild in the future; it's just not urgent.

I have time to think and research my options. The choices abound, but my $$$ do not. A mild compromise between stock and a lot more power is the Euro 3.0, good for 190-200 reported rwhp in track trim.

Option 1, Euro SC: I am thinking of making a 3.0 Euro out of a combination of 78 big port CIS and heads, 82 CIS hardware, and hopefully a set of 9.8:1 P&Cs. I need to learn a lot more than I currently know.

So far I have figured out the Fuel Distributor, WUR, and Airflow Meter are different. The 78-79 CIS airbox, runners and heads have 39mm intake ports, which is the same as the 81-83 Euro. I know a US 3.0 can handle the airflow needs of a 98mm (3.2l) conversion.

My first questions are,

1) Can I get the Euro HP numbers using a combination of 78 and 82 parts, and being clever with the choice of WUR? Has anyone done this before?

2) Will the 78 or 82 Fuel Distributor and Airflow Meter limit me in potential HP verses a true Euro FD and AFM? Does it really matter?

VFR750 · 11-27-2009, 03:06 PM

tom1349racing is helping with a lot of relevant links within PP. I'm building up a parts list, and a target budget for Option 1 = Euro SC.

CIS Guru Question

US to Euro engine specs

CIS Primer for the Porsche 911

Seems making a Euro 3.0 is going to be a challenge to get all the parts, I've missed out on a few deals along the way

FS: 83 SC Euro Large Port CIS Parts

So each day goes by, I figure a little more out, and then I'm adding up all the little details that add cost. More to follow......

ninesixfour · 04-12-2011, 05:59 PM

Still working on this?

VFR750 · 04-13-2011, 01:56 AM

No, the costs to truely convert made no sense. P&C alone are $4K. After looking at the options, i went with Zenith carbs. Engine still running strong so the rebuild is on hold

euro911sc · euro911sc's Garage

Yeah pistons are not cheap... nor easy to find. for the same cost you could move to 3.2...

Glad the car si still running strong!

-michael

VFR750 · 04-13-2011, 03:41 PM

I was getting worried about the engine, but the problem turned out to be I needed to chase down the multitude of vacuum leaks. Worst were the injector sleeves. After adding some black RTV around each one, and checking other locations, problem was solved. CIS ran great after that. Oil consumption is high, but only on track days. Normal street driving burn rate is fine, although hard to quantify, since about half my miles last year were on the track.

I added the Zeniths as a first pass at what a future build might be. Did I want to go the carb route with wilder cams, J&E pistons etc... ? Right now, my feeling is yes, a future rebuild would be based on a carbed engine. May keep the SC cams, as going all the way back to stock is my "10 years from now" plan. (it will be almost 50!!!)

ninesixfour · 04-13-2011, 05:53 PM

I'm tearing down my 82 Euro right now, and crossing my fingers that the Ps and Cs are reusable. If they aren't, this could be a VERY long project.

BURN-BROS · 04-13-2011, 05:55 PM

I would not recommend anything higher than 9.3/1 with a CIS system with pump fuel. I've seen plenty of broken rings because of it.

ninesixfour · 04-13-2011, 06:01 PM

Quote:

Originally Posted by BURN-BROS

I would not recommend anything higher than 9.3/1 with a CIS system with pump fuel. I've seen plenty of broken rings because of it.

What about the 81-83 Euro motors running 9.8:1?

BURN-BROS · 04-13-2011, 06:21 PM

No Sir, It will be just a matter of time before you are in the right environment for detonaton.

Typically, 9.5/1 with single plug is the limit...and that is with carbs.

Keep your compression conservative as the hp increase is very little. You could see some improvement with a backdated exhaust if smog laws are not prohibiive.

spuggy · 04-13-2011, 10:15 PM

If your original P&C's are in good shape and you want to use them, consider a J & S Safeguard. Gives up to 20 degrees (in 2 degrees increments, or 10 degrees in 1 degree increments) of adaptive per-cylinder knock retard.

When it's not detonating, you have full advance. (And a soft rev limiter, if you want). There's M8 studs on the center of the block under the fan shroud that might have been designed for the Bosch knock sensor.

Much cheaper than a set of pistons.

I find on my 930 that with mildly advanced timing for better off-boost response (and increased boost retard so the timing at full boost is back at stock figures), it detonates slightly around 2800 RPM in N/A mode under light load (not enough manifold pressure to start boost retard), and the J&S pulls 2-3 degrees of timing there - but not at full chat, or any other point in the RPM range...

Heck, if you regard it purely as insurance against a bad tank of gas on a hot day or a clogged injector, it still makes sense.

constaf · 04-27-2011, 08:36 AM

Quote:

Originally Posted by BURN-BROS

No Sir, It will be just a matter of time before you are in the right environment for detonaton.

Typically, 9.5/1 with single plug is the limit...and that is with carbs.

Keep your compression conservative as the hp increase is very little. You could see some improvement with a backdated exhaust if smog laws are not prohibiive.

???? you sure you have your numbers right? Surely 9.8:1 run strong for a long time all over the place...

Vin-barrett · Vin-barrett's Garage

Quote:

Originally Posted by BURN-BROS

No Sir, It will be just a matter of time before you are in the right environment for detonaton.

I agree 100%
My SC has these 9.8 pistons and I keep extras on the shelf.
I have broken a piston on two seperate occasions. Both times were on very hot days driving really hard ,just recently autocrossing this past Easter sunday.
(using 93 octane 30 degrees total advance)

See the smoke out the tailpipe? Going to back off the timing a bit again this time.

ninesixfour · 04-29-2011, 02:27 AM

Quote:

Originally Posted by Vin-barrett

I agree 100%
My SC has these 9.8 pistons and I keep extras on the shelf.
I have broken a piston on two seperate occasions. Both times were on very hot days driving really hard ,just recently autocrossing this past Easter sunday.
(using 93 octane 30 degrees total advance)

See the smoke out the tailpipe? Going to back off the timing a bit again this time.

I run whatever premium is available (usually 92 or 93) and have never had a problem, but then again my motor was the original until I started rebuilding it so it likely was down on compression.

Where do you get 9.8:1 pistons to have extras around? They aren't exactly easy to find used, let alone in the correct weight group, and are I have only found them available new as a full set with cylinders.

Vin-barrett · Vin-barrett's Garage

Quote:

Originally Posted by ninesixfour

Where do you get 9.8:1 pistons to have extras around? They aren't exactly easy to find used, let alone in the correct weight group, and are I have only found them available new as a full set with cylinders.

Just got to keep your eyes peeled... see if these work for you

3.0 SC Euro 9.8:1 pistons - 3 only