New Guy with several questions...

[Makoshark72]

Hello all,

This will be brief as I'm pretty busy, but will add my details soon...

Year or so ago I purchased a 79 911SC. Love it! Couple of questions however..

Ride is especially harsh. I really dont have any history of the car. Was told it was lowered to Euro-specs..?? Don't know if the shocks were changed or bushings..etc. Rides like it needs shocks. Any ideas. What to look for to give you guys more info?

Starting is difficult, if it sits for a day or more. Takes a while for fuel to make it to the engine. Almost like there is a "check valve" in the fuel system that isn't "checking", if you know what I mean. Once fuel is present, she fires right up.

Cruise control is inop. Where to start?

These are the biggies. Looks like a great forum. I am very active on the Corvette Forum (3 yrs now) as well as the Factory Five AC Cobra boards (new guy there, also)

Just for info, I am finishing a frame on resto-mod on a 72 Corvette, have done everything short of removing the body. Have done it all myself. Also restored a 67 Land Rover, a 78 280Z and a 78 Land Cruiser FJ40. Just have never owned a Porsche and so not very knowledgeable on 911 specifics.

Help me out here, nothing pressing. Just thought it was time to join and ask the experts!! Here's a couple of pictures to get us started.

Thanks,
Rob
Retired Navy Pilot
Currently fly for NWA (Delta)

[88911coupe]

Wow, nice car....looks like a dead ringer for my '88 3.2. Welcome and I can't really address your questions specifically since my car is motronic but I'd suggest getting Wayne's Books and the Bentley manual as soon as possible. I'm 99% sure there is a Bentley that is specific to the SC but someone can correct me on that if needed.
Had a buddy in HS that bought and fixed up several vette's and they can be a lot of fun.

[Makoshark72]

Thanks. The car runs GREAT, lots of torque even in high gears, surprising to a noob like me. Just rides harsh and hard starts when cold and has been sitting. Maybe someone else has some ideas. Been reading about a check valve at the fuel pump affecting hot starts, seems logical to me this could be part of my problems starting after sitting awhile...

Thanks again,
Rob

[ossiblue]

Welcome Rob. For some reason your pictures won't appear on my work computer so I can't comment on your car, but I' take Buck's word on it until I get home.

Lowering the car to Euro specs will cause a harsher ride, as will low profile tires and larger wheels, stiffer torsion bars, and sway bars. As I can't see your car, I can't tell what, if any, of the above apply but these are other area to consider beyond what you mentioned.

As to starting, you may have a faulty check valve or possibly a bad fuel accumulator. However, hard starting may also be due to a misadjusted Warm up Regulator or malfunctioning cold start valve. Have you had your CIS system pressure tested? Cheap and will give you a bench mark for other diagnostics.

When your car doesn't start, does it just "turn over" for a while and finally fire-up and run smoothly, or does it fire-up and die for a few times until it eventually runs? If you're not getting any firing for several seconds, that sounds more like a cold start valve as it should shoot fuel into the intake when you have the ignition in the "start" position and, if you have spark, there should be some brief fire-up of the engine, at least.

Can't help on the cruise control.

Hope this helps a bit. Let us know what you find, or any other symptoms you can think of. Some one here will find the solution.

[Gogar]

As far as suspension goes, you probably should pull off some wheels and see what you have going on in there. Or, if you have some of the PO's receipts, see if there's any mention of torsion bars or bushings, etc. If it's squirmy maybe it has been set up for a little stiffer ride.

[boyt911sc]

First and foremost check your fuel pressures (system, control, and residual). You need a fuel injection pressure gauge kit to do the tests. There are a lot of guys here here that will direct you how it is done. A good reference manual is Bentley's Manual for SC's.

Tony

[Makoshark72]

Originally Posted by Gogar

As far as suspension goes, you probably should pull off some wheels and see what you have going on in there. Or, if you have some of the PO's receipts, see if there's any mention of torsion bars or bushings, etc. If it's squirmy maybe it has been set up for a little stiffer ride.

Been planning to do just that, just busy with finishing the Vette. All things in time I guess.. I have SOME receipts but not a lot. Just remembered, the guy that sold it to me mentioned that his seller had owned it twice. I have his name and number, might be worth a call. Local guy here on Bainbridge Island (near Seattle).

Thanks!

Originally Posted by ossiblue

Welcome Rob. For some reason your pictures won't appear on my work computer so I can't comment on your car, but I' take Buck's word on it until I get home.

Lowering the car to Euro specs will cause a harsher ride, as will low profile tires and larger wheels, stiffer torsion bars, and sway bars. As I can't see your car, I can't tell what, if any, of the above apply but these are other area to consider beyond what you mentioned.

As to starting, you may have a faulty check valve or possibly a bad fuel accumulator. However, hard starting may also be due to a misadjusted Warm up Regulator or malfunctioning cold start valve. Have you had your CIS system pressure tested? Cheap and will give you a bench mark for other diagnostics.

When your car doesn't start, does it just "turn over" for a while and finally fire-up and run smoothly, or does it fire-up and die for a few times until it eventually runs? If you're not getting any firing for several seconds, that sounds more like a cold start valve as it should shoot fuel into the intake when you have the ignition in the "start" position and, if you have spark, there should be some brief fire-up of the engine, at least.

Can't help on the cruise control.

Hope this helps a bit. Let us know what you find, or any other symptoms you can think of. Some one here will find the solution.

Thanks. Yes the car turns over for 10-15 seconds, then fires up, but runs rough for maybe 5-10 seconds (with a cough and hiccup).. then smooths right out at a fast idle. Once it has been started, I can shut it off and it will start immediately, even when still cold. As if, once the fuel is there, no problems, fires at the touch of the key. Even after sitting overnight, it will start right up. Takes a few days for the "no fuel" symptom to reappear, but it always does. Thats what made me speculate on a check valve that is slowly leaking fuel back away from the engine, if that makes sense???

EDIT...At times after driving and the engine is warmed up, it will occasionally go to a fast idle. Just more info for you guys.

As far as suspension, I'll try to get some pictures of whats there, as like I said, I wouldn't know by looking, if its been modified. After 43 cars and years of "wrenching" I feel like I'm starting all over again with this Porsche!

The beauty of a good forum, lots of answers and suggestions! What did we do before the internet???

I'll try another photo or 2...

Thanks again,
Rob

[FinallyGotOne]

Join the club, I have a 79Sc too. Not sure about the cruise control though, it must be an add -on, I never thought the 79 came with that option.

The ride should not be harsh with those bigger profile tires. As far as lowering to euro height as i did mine, the ride was a little stiffer, but I would not say harsh.

The strut inserts can be done by yourself in the fron relatively easy. You can ask the parts supplier which is teh best strut insert for a more comfy ride. I went with HD Bilsteins.

Hows the alignment? If you do the strut inserts yourself, be sure to cut the last nub of the rubber buump stop off the shocks to give the shock the travel it needs.

I like the Chromed headlight ring, and you got a bonus getting teh laid back euro lights.

she looks like a pretty well kept '11

have you checked if it has had the carrera chain tensioner upgrade, or pop off valve? QUITE CRITICAL updates.

and if you do not have to worry about emissions, you'll get a little more getupandgo from the redhead if you go to a 74 911 header/muffler combo.

[Mysterytrain]

The PET shows that "tempomat"cruise control [auto-pilot] was offered. As for the ride, well it will never ride like a modern car. I re-built my complete suspension , every rubber factory bushing replaced, new shocks, all new bearings etc etc. Rides much better but you still feel the road. Nice looking car..78-79 SC's are great cars SUPER versions of the later carreras

[jmohn]

1) You may have stiffer torsion and/or sway bars but, in truth, the ride in these cars could be described as harsh.
2) Probably cold start valve, maybe warm-up regulator, almost certainly not check valve or accumulator.
3) The "cruise-control" in mine works fine, thankfully, 'cause I'd hate to troubleshoot it.

Jerry M
'78 SC

[Makoshark72]

Originally Posted by FinallyGotOne

Join the club, I have a 79Sc too. Not sure about the cruise control though, it must be an add -on, I never thought the 79 came with that option.

The ride should not be harsh with those bigger profile tires. As far as lowering to euro height as i did mine, the ride was a little stiffer, but I would not say harsh.

The strut inserts can be done by yourself in the fron relatively easy. You can ask the parts supplier which is teh best strut insert for a more comfy ride. I went with HD Bilsteins.

Hows the alignment? If you do the strut inserts yourself, be sure to cut the last nub of the rubber buump stop off the shocks to give the shock the travel it needs.

I like the Chromed headlight ring, and you got a bonus getting teh laid back euro lights.

she looks like a pretty well kept '11

have you checked if it has had the carrera chain tensioner upgrade, or pop off valve? QUITE CRITICAL updates.

and if you do not have to worry about emissions, you'll get a little more getupandgo from the redhead if you go to a 74 911 header/muffler combo.

The cruise was offered, I believe its in the owners manual. Can you tell from the pix if it has in fact been lowered??? Yes both upgrades have been done. And I really love the euro headlights! Alignment? Havent had it checked. The car tracks perfectly straight and handles like a slot car, just really firm, on any degree of rough road..
Thanks!!

Originally Posted by Mysterytrain

The PET shows that "tempomat"cruise control [auto-pilot] was offered. As for the ride, well it will never ride like a modern car. I re-built my complete suspension , every rubber factory bushing replaced, new shocks, all new bearings etc etc. Rides much better but you still feel the road. Nice looking car..78-79 SC's are great cars SUPER versions of the later carreras

I'm certainly not expecting a modern ride, but it just seems a little too harsh from what I expect...Maybe a suspension build is needed. Feels like it could be shocks. If I post a picture, can you guys tell if the shocks are original??

Originally Posted by jmohn

1) You may have stiffer torsion and/or sway bars but, in truth, the ride in these cars could be described as harsh.
2) Probably cold start valve, maybe warm-up regulator, almost certainly not check valve or accumulator.
3) The "cruise-control" in mine works fine, thankfully, 'cause I'd hate to troubleshoot it.

Jerry M
'78 SC

Thanks Jerry,

I feel like we're neighbors. Spend half my life in MSP flying for NWA.

I need to do some investigating re: the suspension. I'll try to shoot some pix soon and post them up so you guys can take a look and advise me.

Is the cold start valve and/or warm-up regulator easy to troubleshoot and if needed, change out??

EDIT*** There is a stiffener between the front shock towers, FYI. It came that way. I've never installed one on any of my cars in the past, so dont really know the effects on ride and handling.

More pictures!!!

Thanks again, I'm liking this place!!

[Gogar]

Nice rear speaker valance! Ugly late-80's steering wheel! (Just kidding! It's fine.)

[SCWDP911]

Very nice looking car! Welcome to Pelican community and to the Plot (see my sig). From everything I have ever read or heard, the cruis controls are crap in the SC's. Mine is there, but sometimes works and sometimes does not. I have only had a few occasions where it would have been nice to have it functional though. Sorry not much help, but if you figure something out, maybe I will try it on mine. Also, when mine did work (engage that is), it would oscillate 5 mph constantly and was pretty much worthless.

Hope to see you register on the scwdp registry soon! Shirts and decals are available...

P.S. Definitely loose the steering wheel - a Carrera wheel has no place in an SC... you will just confuse your car friend...

[Makoshark72]

Originally Posted by Gogar

Nice rear speaker valance! Ugly late-80's steering wheel! (Just kidding! It's fine.)

Originally Posted by Shane Van Wey

Very nice looking car! Welcome to Pelican community and to the Plot (see my sig). From everything I have ever read or heard, the cruis controls are crap in the SC's. Mine is there, but sometimes works and sometimes does not. I have only had a few occasions where it would have been nice to have it functional though. Sorry not much help, but if you figure something out, maybe I will try it on mine. Also, when mine did work (engage that is), it would oscillate 5 mph constantly and was pretty much worthless.

Hope to see you register on the scwdp registry soon! Shirts and decals are available...

P.S. Definitely loose the steering wheel - a Carrera wheel has no place in an SC... you will just confuse your car friend...

Thanks guys. Just goes to show what a new guy I am. I didnt even know the steering wheel was incorrect!!!

[SCWDP911]

By the way, my dad was an old Vette guy. Love to see pics of the 72 sometime. 68-72 is actually one of my favorite body styles, if done right.

[SCWDP911]

SC's used a 3-spoke wheel

[FinallyGotOne]

If your saying there is a tower brace under the front bonnet than that right there is a BIG part of the harsher ride. However, if you remove it I do believe you'll need to get a re-alignment.
From the pic this car looks to be euro height i would estimate. There is a measurement to the fendertips someplace on this board. I'll see if I can dig it up and post it here.

[FinallyGotOne]

well jees, that was easy! The front should be 25.5 inches and thE back is 25 inches. This gives the car about a 1 degree rake toward the front as this makes for the best performance for your daily driven 911
But I believe this is assuming 16 inch fuchs, with standard tire sizes, which it looks like this car has.

So there cruise control on that but no AC or air pump.Seems the previous owner knew what he/she was doing ...

[Bryan A.]

PM'd you.

[FinallyGotOne]

Okay so here are stock euro tire / wheel dimensions, so you can compare thes eto yours, then measure fenders, also if your tires differ check

http://www.1010tires.com/tiresizecalculator.asp

and you can check out overall diameter to make adjustments to measurements.


front wheels F / 16.0 x 6.0 in
rear wheels R / 16.0 x 7.0 in
front tire size 205/55VR-16
rear tire size 225/50VR-16