[DaimLan] SP250 (Dart) Advice

Dear John,
It is a long time since I sold my SP250, but my answers are as follows:-

  1. Mine was a B spec SP250 (registration no 433 JOU). Does anyone know who has it now?

  2. Mine did not overheat when driving, except when the bottom hose got old and soft and would collapse at higher engine speeds, cutting off the flow through the radiator. The hose would recover at idle speeds, so the problem was very difficult to detect. I had to run at an over-fast engine speed for quite a few seconds to see the collapse occurring. The car did get very hot in stationary traffic queues, so I fitted an electric fan, but this almost never switched itself on, so was really only an economy device as it saved energy from being wasted (pushing air unnecessarily).

  3. I seem to remember my engine slowing down noticeably, when the clutch was depressed at idle, but it did not stall. The idle was very smooth. Are your carburettors set up correctly?

  4. I too felt the need for an overdrive and obtained a Triumph tail shaft for the SP250 gearbox and then fitted a Laycock “B” type overdrive. It was a wonderful modification. If I switched into overdrive at speeds exceeding 69 MPH (the legal limit in England is 70 mph) the car would accelerate unless I lifted off the throttle. At higher speeds, the overdrive allowed me to use a lower throttle setting AND a slower engine speed, as well as getting a quieter ride. The unfortunate side effect was that I found it much more difficult to remain within the speed limit and had to sell the car, before getting caught!

4B. David Beales has had casings manufactured to fit the SP250 engine. These casings contain Triumph (TR3 - I think) mechanicals. This gives a stronger first gear as well as an overdrive gear and the gearbox is a direct swap. The only drawback is that you have to use the input shaft from the SP250 gearbox, so have to render the original box unserviceable.

  1. Sorry, I cannot remember the timing requirements. It was over 15 years ago, perhaps even 20.

  2. No need to apologise. Those who do not want to answer do not have to.

Regards, Adrian.
---------------- ************ ----------------
Adrian H. Hanwell.
---------------- ************ ---------------------Original Message-----
From: johntatlow@btinternet.com [johntatlow@btinternet.com]
Sent: 23 July 2002 20:57
To: daimlan@jag-lovers.org
Subject: [DaimLan] Dart Advice NeededPlease

  1. I have recently purchased a c spec dart and have several questions, any help greatly appreciated:

  2. Overheating - is this a problem with these cars - gets very hot in traffic, hot on motorway, fine on a/b roads. car has mechanical fan and new radiator and waterpump

  3. Poor idle - engine stalls when clutch is depressed - fine until you press clutch. There is some visible endfloat on crank pulley when clutch is depressed - any ideas?

  4. Overdrive - what gearbox will fit with minimal modification - the car is original and I do not want to cut it about but I would really like an overdrive for motorway cruising

  5. Timing - manual says 10deg BTDC - the car has unleaded heads and I have been running on unleaded what should I set the dynamic timing at?

  6. Sorry for the number of questions but I am desperate to get my dart sorted

John Tatlow

[Commercial use of subscribers e-mail addresses prohibited.]

To remove yourself from this list, go to

// list policy dictates that messages be trimmed