1979 911 it's new to me..

[hoverEd]

Hello,

Could someone tell me what tire sizes work best on the fuchs 16 inch option on a 1979 911 front and rear?.What should the rim widths be?

How long and how high should cold start high idle be? It starts and reaches 2300rpm immediately. In 8 minutes down to 2000rpm. At 13 minutes it makes street idle. As it approached idle it hunted for idle speed 4 times (300 rpm swing) before settling. Any problems there or is this normal?? Things to check?

Thanks ED

Hello to RonIn LB

[79 Euro]

Hi Ed-Welcome to board and the SC world.
I drive on Bridgestone Potenza (F) 205/55R-16 and (R) 225/50R-16.
I idle just a tick under 1000. I think the book calls for 950.

May I suggest buying The Used 911 Story by Peter Zimmermann
Have Fun!

[tcar]

Originally Posted by 79 Euro

May I suggest buying The Used PORSCHE Story by Peter Zimmermann
Have Fun!

Fixed it for you...

Peter is a member here and posts from time to time. Uses his name.

It shouldn't idle that high when cold; should be 1500 or so. Settle to 950 after 3-4 minutes

[boyt911sc]

Originally Posted by hoverEd

Hello,

Could someone tell me what tire sizes work best on the fuchs 16 inch option on a 1979 911 front and rear?.What should the rim widths be?

How long and how high should cold start high idle be? It starts and reaches 2300rpm immediately. In 8 minutes down to 2000rpm. At 13 minutes it makes street idle. As it approached idle it hunted for idle speed 4 times (300 rpm swing) before settling. Any problems there or is this normal?? Things to check?

Thanks ED

Hello to RonIn LB

Ed,

After driving your car for a while and the engine is its operating temperature (completely warmed-up), remove the oil fill cap and observe for the idle speed change (if any). With the motor @idle (950 rpm), performing the oil-filler-test would tell you several things about your vacuum system. Let us know what results you get.

Cold idle speed should be around 1500-1700 rpm and gradually drops to 1000 rpm between 3 - 4 minutes. A fully warmed-up engine should idle @950. Keep us posted.

Tony

[kramer747]

idle sounds fine. My 83 does that

[RoninLB]

Originally Posted by hoverEd

tire sizes work best on the Fuchs 16 inch option on a 1979 911 front and rear?.

What should the rim widths be?

Hi Ed


chances are you have 6" & 7" Fuchs

I believe stock tire sizes are comparable to
front 205x55x16
rear 225x 50x16



both sizes should be about 24.9" outside diameter

I'd figure for now that if you maintained stock sized tires that are sticky with a stiff sidewall you'd be able to handle N State Pky with the fast late commuters between 9:30 - 11:00 pm between the Meadowbrook and the Sagtikos. The engine weight gets thrown around doing 3.5k - 4k rpm in 5th gear on twisties that were built for 45 mph so stiff sidewalls help big time. Herds of commuters doing 70-85 mph is routine and it's a 50/50 shot to get into a pack. If you miss a pack at the end of the strip go back the other way and hunt for one. You need a pack of 'em or the State HP will pick you off solo. When you get used to that you could then head for the tracks. Driving these cars is a learning experience.

I tend to tilt to "summer" classified tires on Tire Rack - Your performance experts for tires and wheels
Prices for the summer 205x55x16 vary between $90-$175. The listed UTQG rating is for generally accepted tire mileage rating before you get down to the wear bars.

Some members have had experiences with lower cost tires that are great. Some member posts will even state which are over-rated in costs compared to a different more expensive model.

I've seen nice member experiences with the lower cost Kumo

best is to do a search using the tire brand name or just "tires"

many guys have gone through many different brands and models and hopefully you'll find the assistance you need. I wouldn't think picking a tire for a 911 is the same a picking a tire for a normal sport car

a stiff sidewall many be more noise but I never considered it an issue on my loud car. If you're car is quiet and tire noise is an issue open your roof and drive faster.

[kramer747]

Just put Kumho Ecsta's on my 1983 911 that I just bought -I like them so far. Price was right too. Under $500 -mounted and balanced

[hbkramer]

Yokohama ESs are also a decent lower cost option in 205 /225 16's .Or 225/245 16 if you have 7/8" wheels

[Flat6pac]

If youre engine is seeking idle under a 1000rpm, youre probably running too rich.
Bruce

[mholbrook38]

I found numerous vacuum leaks on my 79 SC when I first got it. Replaced the hose from the intake plenum to the oil tank along with every regular vacuum hose (example distributor vacuum hose). My car idles quickly to 950 and starts easily hot or cold.

I think the accepted practice is to immediately drive the car after starting and not idle for long periods of time.

You are going to really enjoy the SC.

[hoverEd]

I hope to meet all you guy's someday and maybe get you drunk or something, but for now I gotta say thanks for being so forthcoming with the info.. As I explained I am completely new at all this forum stuff (stage fright).I can't wait to have some real questions for the group including Vin # dissection so I can find out what this car is etc. I was surprised that it did not have a sunroof and that it had a core type cooler up front instead of a musical instrument. I think I saw some rice though as I recognized a Flam style horn compressor mounted in front of the space saver up front. Absolutely the first thing to hit the garbage can...


I had a little set back today in that my 1979 911 won't be in my possession until about the first weekend in march. Damn that hurts. I assure you it's not all my fault. Funny how things get in the way of your plans. Ordered the CIS bible (Pelican Plug)so I can add an additional fuel injection system to my gray matter.
I ordered a lift today from harbor freight. Floor to 39 " above. Should be a back saver for me. I am getting old... and I need to speed up the work process a bit.

ED