Twin Plug Engine parts.

[james911rs]

I know i am joining this thread late, but ive been talking to Tuthills about twin ignition, they do a 12 point dizzy for £1800 + fitting, but they also do for £400 a second 6 dizzy hidden around the back. Obviously doesnt look as sexy but what a bargain.
Why cant you fit a later 12 point dizzy off a later RS car, because they are ONLY about £800.

[Lightweight_911]

You can fit a 964/993 twin distributor set-up but the reason that people are keen to see an affordable twin-plug distributor is for the period-correct look of the engine.

Up until recently the only option (apart from an original Marelli or Bosch twin-plug distributor) was to buy one of the existing 'conversions' offered by Andial, etc.

I have such a Marelli twin-plug converted distributor in my 2.8 & a new Bosch twin-plug Andial-converted distributor which I bought for my 2.5 short-stroke engine but the problem with both of these is that they still use original Marelli/Bosch twin-plug caps which are £££££ !!

That's why the conversion that David is talking about is such a great idea as it utilises the much cheaper (but visually very similar) Marelli 12-plug cap from the Jaguar XJS V12 (together with a fabricated rotor).

[davidppp]

Hello all.

Updtae:

The rotors are bordered, and we are sorting the design of thre adaptors.

We would like to buy any old dizzys for 911's please..marelli's will do fine..any condition, for mock-ups..

The price may be lower, depending on machining costs.

Thanks
to all who have replied, I will contact you personally when my virtual world settles down a bit..current internet access is via the library only!

Kind regards
David

[Schläfer]

Hi David,

I'd also be interested in what could be done. We had a chat at one of the Midlands meets do you remember I have the Slate Grey '65?

I'm not sure, but I think Tuthill's are using the same Distributor that Carquip are making/selling for $2495. Looks good. Also they're making both sized spinles. Early cars like mine use a 27mm spindle, I'm not sure which year it changed to 30mm. Do you think there would be a better saving if we arranged a group buy instead of remanufacturing?

I take it you're making these FIA compatible so they'll need to fit a 65 more than anything?

Cheers

[fetuhoe]

I was interested to see that Carquip claim that there system is acceptable for FIA requirements and it seems a bit of a minefield.

There is more than one FIA Period under current Appendix K Rules.

I think that this is the list that covers 911s and derivatives.

FIA Period F (1st Jan 1962 to 31st Dec 1965)
FIA Period G1 (1st Jan 1966 to 31st Dec 1969)
FIA Period G2 (1st Jan 1970 to 31st Dec 1972)
FIA Period H1 (1st Jan 1972 to 31st Dec 1975)
FIA Period H2 (1st Jan 1976 to 31st Dec 1976)
FIA Period I (1st Jan 1977 to 31st Dec 1982)
FIA Period J (1st Jan 1982 to 31st Dec 1990)

I have run a 1965 car using Solexes but am now abandoning FIA events and using the car on BHRC events where we can use any "Period" on a Pre 1968 car.

The way I read these rules is that I can use a 911R style engine as Porsche ran the 911R on the 1967 Tour de Corse but I must use a Twin Plug Dizzy with points and is possible the semi-transistorised ignition circuit.

I am aware that one of the Tuthill cars uses two distributors but I am concerned that this isn't a period system. If anyone has proof that this system was used on a Rally car prior to 1968 it would be useful.

I must say that I would prefer to support David's efforts to produce a distributor here in the UK as $2500 is quite a high cost and with shipping, import duty, insurance etc. must be around £1600 to land.

[TheMonkey]

I have been following this thread with interest. I have been browsing the mittelmotor website and they appear to offer a twin plug dizzy. I have no idea whether it's the same as any of the ones that you guys are referring to, but it looks pretty snazzy!
It costs roughly £1500 with caps going for around £100.

I have no idea whether this is good or not.

But I agree, it would be much better to have them made here in the UK.

"Keep Britain in Business"

Having said that, the Germans have made a couple of good cars, but you get the idea!

Good luck with the project

Mark

[PhilipB]

Fetuhoe,

Do you know if the twin plug engine (with correct Marelli distributor) is legal for Appendix K events for a 1968 car? I remember reading in the small print that the 901/20 engine was specifically forbidden - I assumed because the Factory Rally Kits did not homologate twin plug ignition until the advent of the S/T in 1970. I summised that you could only run a 2.0 in twin plug form against machinery from 1970 or later. Would be nice if I have got this wrong so do let me know....

[fetuhoe]

Philip,

Current Appendix K wording is as follows:

"The 901/20 type engine. and the corresponding rocker arms, may only be used in a post-1966 911R"

The 911R certainly ran on several events in 67, 68 and 69.

I am just sourcing a couple of sets of solid rockers and the associated rocker shafts and followers.

[PhilipB]

So does that mean your car actually has to be a 911R or is it good enough that it complies with the specification of a 911R? Reason I am asking is that my 68 TR has a 901/20 motor. Am worried this makes me neither fish nor fowl as far as Appendix K is concerned.

[ChrisF]

Appendix K Paragraph 1.2 states:

"Appendix K applies to cars which are either original competition cars, or cars built to exactly the same specification as models with international competition history complying with International rules of the period"

This seems to me that you can make a 911R replica and use it ithout problem but I you have a T/r you may not have a problem.

I am sure that there are people out there with much more knowledge of T/r's than I have but I believe that when the 911T/r was homologated in 1968 (Group 3 ?) it was fundamentally produced with either a 911S (160 bhp) engine or with an upgrade to 180bhp but that it could be ordered with either a 901/20 or even with a Four Cam engine.

I would have thought you should be able to run the car in FIA events but I compete in BHRC events and there have been twin plug cars used in the last couple of years.

[fetuhoe]

I have spoken to Carquip and they have advised the following:

"For FIA Period F cars we would be the early 27mm, clockwise dizzy – which does not have points. These are breakerless with magnetic pick-up, with roughly 13 degrees advance. I have sold many of these for FIA use, and have not had any problem using two Bosch 3-pin CDI’s, so unless there are some new rules I’m not aware of, you don’t
have to use a “point” system."

"For Pre 1975 3.0 litre cars we would use the 30mm counter-clockwise, but unfortunately, or fortunately - these also do not have points. These again are breakerless, magnetic pick-up. The CCW rotation does not offer any advance."

I must say I am now confused. I would have said that breakerless ignition would cause eligibility problems on both Period F and G FIA cars and that using points was necessary.

I also understood that the RSR in 1974 ran points with 2 x CDI boxes with an advance system. Again I am surprised breakerless ignition is acceptable.

Also what is the opinion about not having any advance because of the CCW rotation?

If this is the system Tuthill's are offering is it strictly eligible and is it a good idea to use a system without advance on rally cars?

At a couple of thousand dollars each and needing to buy 2/3 systems I am really concerned to make the correct decision.

[steve wright]

I got very excited when I came across this site: http://raceservice4u.com

anyone got any experience of them. twin plug conversion using Jag cap, SC body & pukka looking bits to make it work for euro1500 sounds good.

[Herbie9146]

I know an old guy in Ohio who has been making these things with Jag caps for around 750 USD since 1988 ... if anyone wants one, just ask there's no need to buy 10 or more!!!

[steve wright]

do you have a website or pics?

[Nick Moss]

David

What progress is there on this project? I have just started assembling parts to build a 3.0 twin plug motor. Its based on an SC motor and I can send you the dizzy if you need it for conversion.