Anti-Pollution Restore Question

[ctaylor738]

I have been plodding along on the 280SL project.  One of this week's activities was to install the various relays in the engine compartment.  So I attached the bracket and actually found all the various pieces of the anti-pollution set-up.  I have a nice freshly-plated bracket but all the stuff on it is in poor cosmetic condition.  

My understanding is that the purpose of this equipment is to change the timing under certain conditions.  The whole set-up is modular with a separate wiring harness and can be removed without a trace.  So, some questions:

- Would it be a huge sin to simply remove it rather than spend the hundreds of dollars to bring it up to standards?  
- Would its removal cause the car to take a huge hit in show judging?  
- Would it even be needed with a 123 distributor?

Thanks,

[wwheeler]

I can help you restore the rectangular Bosch relay that is to the right of the larger black box. I have the rubber grommets and correct decals in a dry transfer that will make it like new. All you have to do is remove the can on top of the relay base and have it plated. Is that relay a four or five post? Email me and I can give you the details.

Wallace

[hauser]

Chuck

I'm not exactly sure but didn't Bob Possel do away with this after he installed the 123 ignition?   I put this unit in 4,000 KM ago and couldn't be happier.  There's a vendor on the east coast that sells these at a lower price than Brooklyn M.W.

[mdsalemi]

Chuck,

You will take a bit of a hit in judging, but only in an MBCA competition.  No other would know what they are looking at.  You need to pick and choose; I know I have an instant deduction with my color change and SS exhaust system, for example...

[Nate]

Hi Wallace,

Your email address is hidden.  I'd like to refurbish the cosmetics on my relays, the labels are a little worn around the edges.  Can you email me through the website?

Thanks,

Nate

[bpossel]

Hi Guys,

I refurbished my relays and kept everything as is (pollution stuff working), except I installed a 1-2-3 distributor. I toyed with disconnecting my pollution "stuff" but didnt like the way the idle was working. Idle was too high.   After some research and discussion with Gernold, I learned that the throttle body is a key part of this setup. The earlier throttle body is needed along with an earlier distributor with no pollution, relay equipment for this all to work (idle) correctly.  In summary, the throttle body version (retard, advance) is a key part of the correct setup (early or late). Look closely at the connection point for the vacuum line on the early vs late throttle bodies.
Bob  

[Naj ✝︎]

Hi, Chuck,

Bob is right in that the 70/71 throttle bodies provide vacuum full time while the engine is running.
If you want to get rid of the relays etc. you could use just the vacuum valve and operate it with the throttle body switch so that it would only provide vacuum and retard the timing at idle.
When you open the throttle, the valve would shut off the vacuum to the distributor and the engine would run on centrifugal advance as designed.
An earlier ('68/69) throttle body looks very similar to the 70/71 body and would eliminate the need for the vacuum valve if you can find one.

Just my $0.02

Naj

[Jonny B]

Naj,

Wouldn't it be your £0.02?

[Benz Dr.]

The vacuum switch over valve is an integral part of the whole system which is operated by the RPM switch. This started for US version cars in mid 1969 BTW.
If you disconnect the vacuum portion for any reason you will only have about 10 degrees of advance - not very much when you need about 30 to make good power. The only way to eliminate this system is to go back to the vacuum retard throttle body with a 051 type distributor. The later throttle body, with or without throttle governor, is strictly vacuum only at all engine speeds as previously stated.

[hauser]

Chuck

You may want to talk to Peter how his was done.  He is using a 1 2 3 distributor with polution control removed.  Perhaps he can tell you what he did with his.

Here's a link to an earlier post.

http://www.sl113.org/forums/index.php?topic=9984.0

[bpossel]

To clarify, it will run with the pollution equipment removed, disconnected with or without a new "1-2-3" dis.

The problem will be idle.  If you set the distributor at 30@3,000 rpms, the idle will be around 900 to 1,000 vs. a nice 750 rpms.

Bob 

[ctaylor738]

Thanks for the information, folks.  I apologize for not doing my homework on this.  I totally forgot about the differences in the trhottle bodies.

But ...

Doesn't Gernold also have a mod where he drills a new opening in the TB so that the distributor gets some vacuum coming off idle, for better performance?  I recall that from one of the mid-Atlantic Pagoda gatherings.

And couldn't the idle be lowered with the idle air screw, or was it still too high with the screw closed?

[hauser]

I just heard from Gernold this morning.  He'll be in the shop and back to work in a week.

[Benz Dr.]

If you disconnect the original vacuum system and run it with distributor flyweight advance only, it will run - like a dog.......

[wbain]

Add a catalytic converter and drive pollution free. All the fuel is unleaded anyway.