1979 W107 450SLC. Does anyone own - PeachParts Mercedes-Benz Forum

Benzmeister · #1 02-08-2006, 01:29 PM

one of these or a SL, if so are they any performance enhancments. I did put in a K&N filter and I rigged a tube to the air cleaner nozzle to fit behind the grille for cold air intake. But other then that, I have found a replacement electronic ignition system, to replace the oem electronic ignition system, but wonder if these really improve the performance of the V8?

Thanks

300EVIL · #2 02-08-2006, 02:11 PM

Hi Benzmeister,
Which brand/model of aftermarket ignition systems are you looking at?

Benzmeister · #3 02-09-2006, 08:56 PM

It is a Crane XR700 breakerles conversion kit. Even thou my 79 does have a breakerless ignition system, I have read this is a good upgrade and only $119.00. Your opinion please!

300EVIL · #4 02-10-2006, 01:27 PM

I checked out the specs on the Crane XR700 and it seems like a good system. I have never had experience with this ignition system but it's made by a reputable company. Since this device uses an optical pickup you will have to come up with a way to mount the encoder wheel to your cam output. If you feel comfortable with that task then go for it. The next best thing to go with would be a distributor-less ignition system. It wouldn't be any harder to install but will cost a little more.
As for the performance effect on your engine, it will be marginal. I imagine you could gain 5-20 HP based on how far your timing is advanced versus stock. Performance ignition systems produce more HP gains when you have a high compression ratio, forced induction or are using nitrous.
The idea of using an ignition system like this is to produce a more powerful and accurate spark for a larger flame front on your power stroke. MSD uses Multiple Spark Discharge. This creates multiple flame fronts from the multiple sparks to ensure complete fuel burn before BDC. Here is a good article on aftermarket ignition systems. http://www.chevyhiperformance.com/techarticles/45618/
This will help explain things a little better.

Benzmeister · #5 02-10-2006, 05:18 PM

the old and tired stock system. I am comfortable with the installation and not really looking for a drag racer with this car. I am keeping it as stock as possible, IMHO it is a classic and a desirable Mercedes. The car runs very well, the previous owner had the top end of the enginer rebuilt and transmission rebuilt back in 95. But has only clocked 5K miles when I bought it. It did have some drivability problems, but with new spark plugs, and some EXP4 fuel system cleaner. Which IMHO is the best product I have found and works, I went from 12mpg on the highway to 18mpg after a bottle of this product and a couple of tankfuls of 92 octane petrol, which my mechanic a schooled an very good mercedes mechanic recommended. The cars driveability has improved 99%, I just want to get the 1% lost percent back. My mechanic get out the ignition and he said it has a good spark but could be better. The spark plug wire were replaced with the plugs by th way. Timing is right on, and he is not one to fool around with timing, like some mechanic will advance retard etc. He keeps it at stock values, the automatic tranny is working fine, as soon as I gave him the car to go over he changed the shifter bushing to a metal one, as there was a recall back in 84. Mercedes recalled a SL and SLC's to change this bushing. So he agrees the ignition could use an update, but still keep a stock appearance especially with the Crane system.

I have a 99 C280, that, as the young car crazies call it today, tuned, CAI, reprogrammed computer, my mechanic did this himself, next a free flow exhaust. I took the car to a company in CT that had a dyno and the CAI gained and honest 20HP at the rear wheels. No bad for a $175.00 item.

But i have to wait for awhile, I still can't get the hear or AC to work I sent the servo back to the place where it was bought and the fixed it for nothing and told me the potemeter was broken. I fixed two vacuum leaks and a bad elecrical connection. Haven't had a chance to install as the weather has been too cold. I also need to replace the steering damper, which I think I am going to have my mechanic do, as we are supposed to get quite a bit of snow Sunday. Getting back to the heat. One thing the previous owner told me, he replaced the engine water pump. He found out later the impeller was undersized. as it ran a bit hot in the summer, didn't over heat just ran around 200 D F. and a bit higher on a hot day at a light. So, my mechanic and the shop that did the servo, said if I still don't get any heat or not enough, the water pump got to be the culprit? I also know how to set the chain in sequence onces the servo is back in. And I replaced the aux fuse and bought a new aux water pump, and in car sensor. and replaced the foam like hose the sensor uses to measure air temp. The ambient sensor is OK. and the coolant has been back flushed, with the servo off, and I bought a new amp. So if the heat is not working or there isn't enought, I guess the enginer water pump is the culprit. Any thoughts on this? I would appreciate any input.

300EVIL · #6 02-10-2006, 08:21 PM

I'm not familiar with the 107's climate control. However, if your blower and controls work fine but the heat temp is low I would check the aux pump's operation or the thermostat. You can directly connect the pump to your battery to check it's operation.

Benzmeister · #7 02-10-2006, 09:42 PM

bleed the system several times, and it is working OK. One time I jumped it I drove the car so the air would blow our of the system faster and the heat should have come on. But what would happens whether the aux pump is working on its own or jumped you get a burst of heat at each setting, once the engine is warm and then if gradually goes to luke warm. You can disconnect the ambient temp sensor under the hood on the blower housing and the system should blow hot air no matter what setting or what temp the dial is set at. Even then it started hot and when cool The only time I do get heat is in emergency mode. This is a good indicator if everything else is working, except the SERVO or Amp. Emergency mode will always pump heat out of the defroster and the window side vents. This indicates a couple of things which all lead back to the SERVO or amp. The thermostat is OK, as I took it out, as on the 4.5L it is easy to remove and there is a bypass valve if the thermo fails. It tested out fine. When I sent the servo back this time, and this servo has the alumunium body. The previous owner had bought a reconditioned one and the body was replaced with alumunim instead of the plastic OEM. The company replaced all the inner's in that part of the servo, benched tested it and sent me a copy of the bench test and it should throw out plenty of heat. I have an extra amp also, which I know is good. But there is still the procedure of balancing the entire sensor chain, which if I would have read a little further into the shop manual I would have found, as it is not listed in the index? If none of this works then I have to fall back on the water engine water pump. , Mercedes only used them from 78 to 80 and they bought the rights for the system from Chrysler who used them in late 60s and 79s Imperials no less. There is a company that sells a manual overide setup for these unreliable systems. Every stays intake, but you add a water valve, like the old Porsche had and VW's had. some tubing and a manual choke like wire and handle, The one extra part they add is a electric switch to switch back and forth from heat to AC, but other then that part, the rest manual. The valve is mounted below the SERVO and the fluid into tube into the servo is mounted to one end of the water valve and the servo out tube that goes to the heat exchanger, is mounted to the other end. and the Choke wire and handle are run thru the firewall. The site only gave directions up to that point, if didn't say how the AC would work, but I inagine the electric switch is the answer, All the functions on the dash controls are supposed to work, as far as direction you want the heat or AC to do and the fan speed etc. But it did say to control the heat itself would mean using the choke cable to lessen or increase flow for heat and also to mix the AC and heat if the car gets too cold or hot. I had a 912 many years ago, and it's heating system had a similar system, no AC in those cars, not until they were reintroduced in the early 70s between the death of the 914 and the birth of the 924. I also had a 86 911 with factory air and heat, it had 12 fans to control this system, and just as any old bug or old Porsche, the sytem was horrible, the only part of it that worked well was defrost, but used the 911 as a daily driver for 2 years. If I didn't need AC in the summer, for health reasons, I would buy my own water tube the choke cable and hook it up for heating only.

But perhaps this time the servo is really fixed and the water pump is not a problem and I might have some heat for the rest of the winter.

In a way I actually like driving the 450 as much as the C280, especially since you have to the the 450SLC and it is not point and drive like the C280. I'll keep you posted on what happens. I was going to do the job tomorrow, but we are expecting a blizzard starting tomorrow night and very, very cold temps so I think I will have my mechanic install the servo and we will both go over bleeding and balancing the system on Monday.
By the way you go some very nice cars. The 99 C280 was my first Benz and the reason I bought it was for the comfort of the seats, as I have adegenerative back condition and the doctor don't expect me to be walking more then a couple of years at best. So the 450SLC is probably my last project car.

t walgamuth · #8 02-10-2006, 10:43 PM

but it sounds like you are making the best of the time you have to use it.

i have always wanted to drive one of those to see how they drive.

i came close once; my buddy and i went down to indy to look at one but the seller wouldnt let us drive it. it was a very cheap price but the deal looked kindof fishy. he wouldnt let us drive it at all. he just backed it out of the garage and let us hear it run.

it was a very nice looking clean car. maple yellow. about 8 years ago i think.

good luck.

Benzmeister · #9 02-11-2006, 11:05 AM

part is my wife of 31 years is divorcing me. Recently I found out all her BS about me was to take attention off her adultery behavior. Worse part, the divorce court doesn't give a damm about this, even thou it is a felony in Mass.

Sorry to dump. Back to the 450. This car is a delight to drive, it is no a sportcars, but what I call a gentlemen's coupe. It rides well, handles, decently and is quick, especially above 3000K RPM. It is a combo of sport and touring car. The W107 in its many incarnations was the best selling car in Mercedes history until the C Class was released in 94. Also, after the 2000 C Class was "redesigned" C class sales dropped by 50 per cent.

I feel Ok today, so I am going to at least hook up the servo, as it is not hard, four hoses an bank of vacumm hoses mounted on a rectangle piece of rubber that snaps in and is held with one screw, and three electric connections. Afte the blizzard passes I will start the balancing and see what happens.

As I said if you folks are interested in the results I will post them?

Thank you for your interest and kindness and help. I appreciate it very much