Difference 3.0 vs. 3.0 Euro

[mikequig]

The season is over - thoughts turn to rebuilding the stock '83 SC motor that I shelled this summer. Euro P/C rebuild sets are available for a few dollars over the stock SC setup. My question to the board is "what else is different on the true Euro motor that I would need to address?" Is it larger ports in the heads, larger throttle body on the F.I.? Cam profiles? Distributor curve? If I'm going to do it - I want to get it right. Thanks in advance

Mike Quigley

p75 - 911 Class "F" PCA

[1980SC]

Well, from what I've gathered :

The 9.8:1 euro 3.0's from '81-'83 had K-basic CIS with a special fuel distributor which flows more fuel. If your '83 is a US model, you'd have to dump the frequency valve, and go with the euro '81-'83 F.D. and a vacuum controlled WUR. Deceleration valve is like the USA pre-'80 and the euro's have a thermovalve.

The intake ports are the same 34mm as your '83. Not the wider 39mm as on the earlier 3.0's. I don't know about the throttle body size.

Camshafts are the same, but are timed more retarded than the US '83.

I read here or on Rennlist that the ignition distributor had a special advance curve and only advanced to 25* total. I don't know any more specifics on that. They only had vacuum advance, but not vacuum retard like the post-'79 US models.

They also had smog pumps, but I doubt you'd want to add one of those.


Rob
1980SC Euro <--- nothing special. Only 8.6:1 compression

[Bobboloo]

I would think that changing to the 9.8:1 euros and everything else being the same would give you slightly better performance and a cleaner running motor. The performance wouldn't equal euro performance but it should be better.

I guess this would also require the use of premium gas as well.

Bobby

[dd74]

Does the addition of a backdated exhaust on an '83 US-spec 3.0 more or less equal the overall performance of the higher P/Cs and fuel dizzy differences of the Euro-spec 3.0? In short: if backdating the exhaust yields close to the same horsepower for both motors (200 vs. 204 hp), I'm not so sure there's an advantage of a Euro 3.0 over a US 3.0...

...But then again, if one were to have a Euro 3.0 with a backdated exhaust, wouldn't the horsepower be something in the neighborhood of 220 to 225?

This factors in from BA's book, and what I've read on the board.

Anyone have any ideas on this?

[Bill Verburg]

Does the addition of a backdated exhaust on an '83 US-spec 3.0 more or less equal the overall performance of the higher P/Cs and fuel dizzy differences of the Euro-spec 3.0? In short: if backdating the exhaust yields close to the same horsepower for both motors (200 vs. 204 hp), I'm not so sure there's an advantage of a Euro 3.0 over a US 3.0...

One set of #'s doesn't tell the full tale of potential performance. Ignoring factors external to the engine a 190hp 2.4S sounds just as potent as a 200hp Carrera 3.0. It's not even close except on a race track where the gap is reduced but never closed. The h/c p/c will increase torque across the board. Since torque at revs is a good indicator of performance and assuming that cis is retained, the most potent combo will use;

• h/c pistons(w/ bigger displacement which isn't that much more $ if you are buing p/c anyway)
• happier cams the 993/964 are reported to work well
• massaged ports
• ssi's

I agree that the euro f/d is probably required(we needed to add one on the last 98mm SC we did, but it may have been just that the old one was on its last legs anyway)

[78targa]

Mike,

Ok, I figured I might as well chime in here. The 1980 I own has had the work you were looking at doing. The car started of as a 1980 USA Spec and around 90k miles the original owner had the compression increased to 9.8:1. Around the same time he backdated the exhaust to pre '74 HE's. The CIS has not been touched nor have the intake runners been changed. Parts I am currently looking for by the way.

You can keep the USA CIS, but you will loose 8 HP? as compared to a true EURO spec engine. I am winging the number here a bit, but that is the best guess from all of the people I have spoken with.

Ok, so what do you get with the higher compression P/C (andial) and the pre '74 exhaust? Hehe, a car with a nice kick in the pants. Your torque band no longer starts around 4000 RPM. Now it is at 3000 and it pulls strong all the way to red-line. I guess I figure I have around 220HP with these two mods.

The car now has 192k on the odometer and I am aggressively tracking the car. It is a blast to drive on the track and the engine is very solid.

Having owned a 1978SC along with this beast I can tell you there is no comparison in torque. It is a awesome upgrade if you have the time and money.

Quick plug: If there is anyone out there with EURO CIS components and selling, let me know! I am trying to get this engine spec'ed out properly for club racing and having difficulty finding these components!

SCWDP sleeper!

[mikequig]

Casey, you are spot on here. However, I have heard that using the intake runners from the '78-'79 USA version (larger ports) will get you to true Euro spec. That, and cam timing and some distributor work.

I am thinking that short of buying an engine out of Europe anyone contemplating this upgrade will need to cobble it together as there are relatively few US delivery Euro motors out there (much less being parted for the FI). On the issue of the fuel distributor, I'm not certain what the ultimate HP loss is by going w/ US version.

I will wait until the PCA decides what the classing will be for the Euro SC and if they don't penalize it to much (move it to "E") then I'll buy the jugs and put it together. The dyno will tell the rest and I'll report back then!

Thanks, Mike

[1980SC]

In my first post, I was just listing off the things that were different between the US engines, and the 9.8:1 euro engines. I would only bother with the F.D. if you were running lean.

Changing to the '78-'79 3.0L intake runners does not make an engine "true euro" spec. It makes it '78-'79 3.0L spec. The original 9.8:1 european engine in question had the smaller runners just like the USA '80-'83.

Rob
1980SC euro

[Jess]

Hey guys, a little help here.

Let's not give him too much good advice, he races in my class!

Mike's already fast enough. Any faster and he'll beat me.

I think that the real question is what is legal in "F" Stock Club Racing. I don't think that you are allowed to "mix and match." In other words, you can't take the good 9.8 P and C's and team them up with the early SC heads and intake runners. Does this go on? Absolutely! Is it allowed, no.

If you run the larger ports and runners, you must stick with the early SC 8.5 or 9.3 (Euro) P and C's that originally came with them. The 9.8 set-up never came with the larger ports and thus, is not allowed in Stock F class.

Having said all of this, it just occured to me that my Euro SC racecar is in Mike's trailer as I type. He's got my keys and plenty of tools. I'd better check my engine number for that much desired 930/10 the next time I see it!

Jess
(another Class "F" driver)

[78targa]

Jess,

Interesting on the intake runners. I was actually under the impression that EURO spec from 81-83 used the same runners as USA 78-79. Thanks for the info. One less thing to change.

I know there was a different fuel distributor on the 81 EURO, any differences in the airbox?

As a future hopeful in class "F" I am looking to make sure I don't make mistakes in specing this car right. As the car already has the 9.8 p/c I have two choices: Make a 81 EURO clone out of a 80 USA or run in GT. I don't have the deep pockets for GT. Then again I hear it is pretty easy to spend a lot in stock...

Any idea where to get all of this good information in writing? I am having little luck finding sources of info on 81 EURO options as well as engine configuration.

[emcon5]

Originally posted by 78targa
Any idea where to get all of this good information in writing? I am having little luck finding sources of info on 81 EURO options as well as engine configuration.

Bruce Anderson's book has the port and valve sizes.
http://www.911handbook.com/

Tom

[DonDavis]

My 71's engine is a ROW 3.0 #930-03. Kind of a long story on how I came across the car so I'll save that. I could not get documents on the engine so I'll list what I can. It has the standard SC exhaust on it and a few other visible mods that my "un-trained eye" can detect. Things like turbo valve covers, tensioners and pop-off valve. No smog stuff or a/c. Oh yeah, it runs GREAT!

Casey was saying that torque kicks in closer to 3K with the 9.8:1 p/c. I can say that my car takes off well and has LOTS of pull at 3K and is still pulling hard as I approach redline. Is he saying that there is a definite difference that I should feel if my engine had the 8.5:1 as spec'd?

I suppose the answer will be something like:

" It's kind of subjective and without tearing down the engine, we won't know for certain"

but I was wondering is there another way to check? Outside markings visible on cylinders? and there was a statement about the CIS and the F/D ( fuel distributor??)

TIA

[piedogger]

I have a factory 83 euro sc and it definitly has the larger intake runners and bigger ports.

[NapTownSpeedy]

While browsing eBay after reading your discussion I noticed this Euro FD
It is listed as a Euro Fuel distrubutor, part no. 0 438 100 092
So maybe it might help you guys out. But at time of posting just over 4 hours left.
You're going to have to scramble with those part numbers.

[mikequig]

Ok, I have done some research on the 3 engines that I have access to and here are the findings:

1979 USA 3.0 w/case # 930/04 or 06

Intake runners = #911 110 169 4R(larger)
Fuel Distributor = unknown #
port size (from BA's book) = Intake
39mm, Exhaust 35mm (largest intake produced)
CR = 8.5:1

1983 USA 3.0 w/case # 930/16

Intake runners = #911 110 169 2R (smaller)
Fuel Distributor = Bosch #0 438 100 077
port size = Intake 34mm, Exhaust 35mm
CR = 9.3:1

1981 Euro 3.0 w/case #930/10

Intake runners = #911 110 169 4R (the big ones)
Fuel Distributor = Bosch # 0 438 100 097
port size = Intake 34mm, Exhaust 35mm
CR = 9.8:1

All engines have the same 49mm Intake and 41.5mm Exhaust valves

In summary, the 78-9 has big runners and big ports but the lowest compression. The 83 USA has smaller runners and ports and slightly higher compression. Both engines yield the same 180HP and 175ft. lbs or torque.
The Euro engine has big runners feeding the smaller ports. The magic must lie in the squeeze of 9.8. The wild card is the fuel distributor which I can't see making that much of a difference. The Euro produces 24 more HP and 14 more pounds of torque. You can time the cams and ignition all you want and not get that kind of increase from the USA versions.

Footnote: The ultimate "cheater motor" would presumably be to marry the biggers port to the large runners and Euro P/C's. The dyno would tell, but then why did Porsche abandon the larger ports after 78-9?

-Mike

[Jadams1]

I have a 1980 Euro SC, I don't have the car with me today but I have the part number for the WUR with the vacuum line.

engine type 930/09

serial no. 6300427

WUR p/n 911.606.105.09

I'll check the fuel distributor when I get home.

p.s. Great thread!

I

[mikequig]

John,

Your mention of your 930/09 case sent me back to Bruce Anderson's (also known as "god") 911 Performance Handbook (also known as "the Bible") for info on your motor.

For the purpose of this discussion we will call the 1980 version "Euro-lite" as it produces 188 HP and the same 175 ft.lbs of torque as the USA SC 3.0. Not the 204HP and 189 lbs of torque as does the 81-83 Euro. The explanation for these lower values for Euro-lite lies at least in part in the 8.6:1 compression ratio vs. the 9.8:1 of the more muscular 81-83 motor. But what else is different?

The valve timing is different between the two. but durations and overlaps are the same. I would think that lift is the same as well, i.e. same cams - timed differently. Might move the torque band around but not change the overall values.

It looks like anyone who owns the 81-83 with the 930/10 case has the best that Porsche had to give.

SCWDP

-Mike

[1980SC]

Well, I've got a spare set of the larger '4R' intake runners. What are they worth?


Jadams1 -

Please do post your F/D part number. I had to replace mine with the US model '78-'79 style. 0.438.100.031.

Rob
1980SC euro

[Jadams1]

Rob
1980SC euro

BOSCH number on my FD is 734.020.916

How did the US model FD work out on your car?

[1980SC]

Well my car had the US lambda style F.D. on it. That was horrible. Works great now with the US non-lambda style F.D. I assume it would be same, or very close to the '80 euro style.

Do you have a 0.438.100.XXX number off that F.D. of yours ?

Thanks,
Rob
1980SC