Improving performance

Hmmm, they sound like the go. Of course I've got to spend money on other things first, and the old ones (some off-the-shelf items) are doing their job at the moment, but the Magnecors are going to be added to my list.
 
Gents

Well there I was, Magnecor HT leads, Pertronix Ignitor and Flamethrower coil in hand.

The HT leads went on first............no problems there.

Next the Ignitor, taking extra care not to drop any nuts or washers down into the distributor.............no problems again.

Distributor cap back on...............hmmmm seems to be a bit tighter than before but it went on..........no problems (or so i thought)

Lastly after checking the ballast resistor on the old coil I fitted the Flamethrower........no problem.

Double check all connections, key in the ignition..............she wouldn't fire.

First check was that tight distributor cap. I took it off to find the centre electrode broken off and sitting in the distributor body. Thankfull that it hadn't dropped any further I checked all the ignitor fittings to see why this had happened. It turns out that when I fitted the magnetic collar over the distributor shaft it prevented the rotor arm from going down a fraction less than without it. This caused the rotor arm to sit a fraction higher and caused the tight feeling to the cap retaining clips.

Has anyone else come across this problem before or is there a problem with my distributor (apart from the obvious broken cap now :( )

I've ordered a new cap off ebay but I noticed there were 2 on sale with a different part number, both billed as being suitable for the P6. GDC117 and 44790. The parts catalogue on Rover Classics reference page lists the former as correct. Can someone please confirm. Is there a cap with slightly more clearance to allow for the raised rotor arm following fitment of the magnetic collar. Pics of my distributor pre and post ignitor fit below.
 

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That's a bad design if it prevents the rotor arm seating properly ,However you only need to grind the thickness of the collar off the base of the rotor arm

It's been said all V8 caps fit as I asked the same question recently
 
Thanks Dave

I spoke to the guys at Carolina cars who market the Pertronix system in the UK and he thinks it might be an after-market dis-cap. He reckons this Pertronix system is designed specifically for the Rover dis-cap and he's never heard of one not fitting. He said he would check though.

Grinding the thickness of the collar off the bottom of the rotor arm requires a grinder...... last time I looked I was nil stock on that particular item, but I'll bear it in mind thanks :D
 
Hello Dave.
As I understand it, you have two different types of dizzy cap and rotor. The carb type, and the EFi type. The carb set is bigger ie: taller dizzy cap and a rotor that is taller and wider, in more of a vee shape. The EFi set is smaller ie: lower dizzy cap and smaller rotor arm that is lower and leaner.
I have had this problem before in trying to fit bigger rotor arm to EFi cap etc..
 
Lee

Any idea why the EFi one would be different. Are the spark plugs and HT leads different too?
 
I haven't much info on why the cap and rotor is smaller on EFi cars, other than perhaps the electric ignition component use less area in the dizzy than the points set up, offering more under bonnet clearance.
The spark plugs are longer (19mm spark plug head castings))on post-P6 V8 engines (SD1), Carb or EFi. 12mm spark plug head castings are used on pre-SD1 V8 engines.
Ht leads are all interchangable, although there maybe a slight difference in length with original spec P6 leads as apposed to SD1 leads, but marginal.
 
LeeEFI wrote,...
As I understand it, you have two different types of dizzy cap and rotor. The carb type, and the EFi type. The carb set is bigger ie: taller dizzy cap and a rotor that is taller and wider, in more of a vee shape. The EFi set is smaller ie: lower dizzy cap and smaller rotor arm that is lower and leaner.
Click to expand...

Hello Lee,

Sorry Lee, but as I understand it, there is no difference in the height between the caps, certainly in the case of the genuine Lucas items.

I have both a 35D8 distributor as fitted to the P6B and a 35DLM8 distributor as fitted to an EFI Range Rover, Land Rover Discovery etc sitting in front of me, and both caps will fit without problem on the other distributor. Sitting both caps side by side shows both to be of the same dimensions.

The difference between the two caps is not of dimensions, but rather internal design. The cap and rotor for the P6B are designed so that the metal contact of the rotor faces directly the contact within the cap, whereas with the EFI distributors the tip of the rotor goes beneath the contact within the cap. The design of the contacts within the caps are completely different, and as such the rotors must match accordingly.

The lengths of the spark plug leads will vary depending on the Rover V8 engine to which they are fitted. When buying Magnecor leads, specify that you have a P6B or an SD1 then the leads will be the same lengths as those fitted by the factory. From 1987 onwards, Rover moved the position that all leads have on the distributor cap by one position so as to limit the possibility of cross firing between cylinders 5 and 7. This being of far greater significance with engines equipped with a management system.

Ron.
 
Gents

A general question under this heading. Will a standard spark plug wrench fit the Rover V8 engine or do I need a Rover specific one? The reason I ask is because when I went to remove the plugs on my car for the first time my spark plug socket in my socket set would not go in far enough to engage the flats on the plugs. ie it was too thick to slip between the plug and where it screws in.

Cheers

Dave
 
SydneyRoverP6B said:
Hello Lee,

Sorry Lee, but as I understand it, there is no difference in the height between the caps, certainly in the case of the genuine Lucas items.

I have both a 35D8 distributor as fitted to the P6B and a 35DLM8 distributor as fitted to an EFI Range Rover, Land Rover Discovery etc sitting in front of me, and both caps will fit without problem on the other distributor. Sitting both caps side by side shows both to be of the same dimensions.

Ron.
Click to expand...

Hello Ron.
Well...It was a bit of a grey area for me, but there is a difference as you say, but not in height. I think the change came with the 35DLM8 dizzy, as this is fitted to late (85-on) SD1 cars and Land Rovers of that period. But Land Rover quotes the leaner rotor as an EFi one, and the bigger rotor as a carb one, perhaps as a rough guide, as most Rover/Land Rover V8 cars were EFi from that period. The dizzy caps are obviously different, and must be matched accordingly.
Cheers for enlightenment.
Lee.
TwinPlenum3500S said:
Lee I assume you are runi=ning an SD1 efi?
Click to expand...
Hello Jim.
Yep, I have an SD1 EFi. The P6 EFi is actually my fathers, although I used to own it, regretably having it converted to EFi in my ownership. I now have the job of working on it from time to time :roll: But the P6 does run very well now with EFi, and proves to be an enjoyable, powerful, and economical alternative to carbs.
I've been following your conroversial TwinPlenum project, and I must say you've done a great job. It looks the part. I wished I had gone for the Vitesse spec EFi when I had my old P6 done, giving a bit more excitment at the higher end :LOL: But the standard Range Rover EFi is powerful enough I suppose.
Lee
 
Dave3066 said:
Gents

A general question under this heading. Will a standard spark plug wrench fit the Rover V8 engine or do I need a Rover specific one? The reason I ask is because when I went to remove the plugs on my car for the first time my spark plug socket in my socket set would not go in far enough to engage the flats on the plugs. ie it was too thick to slip between the plug and where it screws in.

Cheers

Dave
Click to expand...

Hello Dave.
I had my spark plug wrench milled down so it fitted properly. But you should be able to use another normal long reach socket to remove plugs, as long as they're not too tight to undo.
 
Lee any ideas about cold start problems. My fuel pump will not pressurise system when cold and hence cannot start in morning unless I stick my finger up afm.
 
TwinPlenum3500S said:
Lee any ideas about cold start problems. My fuel pump will not pressurise system when cold and hence cannot start in morning unless I stick my finger up afm.
Click to expand...

Hello Jim.
As you know it's very difficult to guess. But, you could start from basics and test your fuel flow from tank (as your not too sure about your present pre-filter), and go from there ie: checking it's flow at the filter when cranking. If flow is ok and fuel pump works you then have to test each component, coolant temp sensor, cold start injector, thermotime switch, etc.. It could also be that someone has tampered with airflow meter, normally evident by glue around the cover. Also the fuel pressure regulator could be naff.
And don't forget to test the ECU, that could be on the way out. You'll have to get out the multimeter to check each component obviously.

From what you've said so far I would be looking at fuel flow from tank through pre-filter, and then pressure from pump. Then CTS, TTS, CSI etc..
 
Labouring the point about distributor caps - are the blue ones different from the black ones ? Prices on Ebay seem to range from £7.99 to £40+
 
Hello Dave,

From what I have heard, the reason distributor caps for the same application vary so much in price comes essentially down to the quality of manufacture. Some of the cheaper caps can fail in a very short space of time due to cross tracking between the contacts and as such will require replacement.

Ron.
 
There's a black one for sale at £7.99 which says it fits P6's and SD1's up to 1981

Vendor says -

Brand new top quality distributor cap

Part Number 44790

Applications:
Rover 3.5ltr V8 & Coupe 1969-72
Rover 3500 V8 Auto 1968-72
Rover 3500S V8 Manual 1971-72
Rover 3500 V8, 3500S V8 1972-76
Rover SD1 3500 1976-81
This part fits the vehicles listed above. Please do not ask if it fits anything else! If it would fit anything else, we would say.


Looks like an Intermotor box
 
DaveHerns said:
Vendor says-

Brand new top quality distributor cap

Looks like an Intermotor box
Click to expand...

Either one or the other of those statements could be true, but not both................
 
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