DDK - Die Deutschen Klassiker

Hi All,

Just wanted to share my excitement at taking my 2.2 911S to the rolling road today and it being transformed by a combination of using the Porsche CMA guide and the modern tech of rolling road and lamda sensors etc. Got it driving really nicely, no nasty popping and banging etc and 178 hp at 7000 rpm... so very happy.

A few fixes to get on with to finish now that maybe some people might be able to help on!:

1) Horn goes off when turning corner - there was nothing obvious when I looking at the copper disc that the horn works off?
2) Rev counter is reading approx double and jumping around - I probably need to speak to Classic retro fit as it is being driven by their CDI box but if anyone has any experience on that it would be gratefully received. From eth web the jumping around may be alternator based but don't know how you check that?
3) Gearshift is taking me some time to get to grips with!. It is a rebuilt gearbox and linkages are all new but its all floppy and imprecise. I know there is a world of different shifters - does any one have a recommendation or one they want to sell?

Cheers

Roger

Great news, is this something that any rolling road place can do, or it needs someone with early 911 experience?

The guys I took it to are a couple of miles down the road to me. They normally tune their VW/Porsche moderns with laptop on the rolling road but they are very savy and understand how engines work. I have been through the CMA and was happy to adjust the pump main and idle screws, and see what the results were and then keep tweaking it. The key observation is that with obviously only 2 screws to adjust across the rev range you are always a compromise compared with what they are used to dealing with where they can tweak fuelling across a map.

Bearing in mind this was a ground up rebuild, I had spent a fair amount of time in setting it up myself but without the lambda sensors and being able to put it under load I couldn't get it anything like right. With the lambda sensor it was pretty easy to see what the adjustment screws did and get it running right.

HI Roger, for a simple but effective improvement to your gearbox you may want to look at this simple spring
https://forums.pelicanparts.com/porsche ... e-can.html
I put it on my rebuilt box & it was a huge improvement
Regards

The floppiness could be the nylon bush at the base of the gear stick, did you replace that along with the others. Mine looked fine from the top, but when I took the gearstick out, it just crumbled to dust!

915 box, but in my many years of these boxes, factory shifter and all new bushes plus adjustment very carefully made will be the best.
Oh, and pictures are required!!

WEVO gateshift - replaces the imprecise fork arrangement within the gearbox.

Accessible in-situ, but mine was fitted during an overhaul which included bearing retainer upgrade etc.

Thanks all, will look at the gearbox suggestions. Hopefully here are some pictures from today:

https://www.flickr.com/photos/151746384 ... 58FxJ64k04

https://www.flickr.com/photos/151746384 ... t15GaAFzBo

https://www.flickr.com/photos/151746384 ... B1934x6907

Who was it with the rolling road in Cornwall please?

About time Roger. Enjoy.

There's a tacho test mode on our CDI+ box. Remove the button head screw on the front of the CDI+ box. Turn on the ignition (do not start the engine). insert a small screwdriver and press the internal switch once. The taco should slow sweep from 0 to 7000 RPM and back smoothly. If it doesn't, then it will be the tacho.

There are 4 test modes described in the manual on page 17:

Manual is here: https://www.classicretrofit.com/pages/m ... d-software

Thanks Dave!

Yes Rolling road is in St Agnes - RK Engineering

Thanks Jonny, did send you an email but will do the diagnostics, thanks

I personally would't use a wevo shifter. Short shifters move the pivot point of the gearstick and put more strain on the components. Changing the bushes with fresh genuine Porsche bushes will improve precision, as will getting the gearbox linkage adjusted by someone who knows a lot about 915 gearboxes.

Regarding the horn. Sounds like your horn ring is not properly seated or you are missing the conical shaped spring that sits under the horn button.

Regards
Paul

.

/\/\/\

Agree with Paul's comments above (although it's a 901/911 'dog leg' gearbox not a 915).

IMO with all linkage bushes in good condition & adjusted correctly, there's no need for any alteration to the Factory set-up ...

.

Lightweight_911 wrote: ↑Mon Jul 24, 2023 4:26 pm .

/\/\/\

Agree with Paul's comments above (although it's a 901/911 'dog leg' gearbox not a 915).

IMO with all linkage bushes in good condition & adjusted correctly, there's no need for any alteration to the Factory set-up ...

.

Totally agree with Andy. In any event the 'dog leg' box is part of the character of a 2.2S.