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Mallory Dual point-Unalite and A & R Ignition Amp Systems upgrade
mallory Ignition overview and check list.
Setting up and checking for problems
Earlier single points systems
Original equipment electronic ignition systems
RPi exclusive A&R Power amps
Distributor-less systems 'Gems'
Mallory Dual Point system
Mallory Unalite Electronic system
Upgrading Ignition systems for LPG use
Customer comments

Igntion overview and check list.

Firstly a checkup and overview of the most common Rover V8 ignition system types.

Ignition check list

{short description of image}First, remove advance vacuum pipe from intake and check for positive vacuum when throttle is applied.
{short description of image}Check (if fitted) that the vacuum delay module is not blocked.
{short description of image}Check positive vacuum will pull distributor advance whilst also checking vacuum module is not holed (when sucking the pipe, the base plate of the distributor should rotate anti-clockwise about 15 deg.).
{short description of image}Check condition of rotor arm for signs of damage or arcing, also check cap and clean contacts (better still, fit new).
{short description of image}Check rotor for free play, there should be none, both rotationaly and side to side.
{short description of image}Check rotor will turn clockwise through about 20 deg, and smartly retract back to its home position under good spring tension.
{short description of image}Distributor output is known to be weak so upgrading with our Spark amp is recommended. (see below).
{short description of image}Replace plug leads, preferably with Magnecor. Use good quality Plugs such as NGK BP6ES, avoid fancy plugs as they don't normally last long.

Setting up and checking for problems.

A check list of common simple issues

{short description of image}.Being sure of TDC position with regard to crank-indicated timing mark is a must.
{short description of image}Plug gap needs to be 0.8mm - 0.9mm.
{short description of image}Don't use resistor plugs and suppressed leads together.
{short description of image}Std. spec. high street leads may not be able to handle the extra spark KVs.
{short description of image}Check fuel delivery pressure.
{short description of image}Check Carb float bowl height.
{short description of image}Check no blocked or restrictive fuel filter in line.
{short description of image}Do you have the fuel return hose (to the tank) connected? If so, it needs restricting.
{short description of image}Try an alternative coil even if yours is new?

{short description of image}Most importantly

You cannot trust the indicated timing marks on your engine's bottom pulley. We have found them to be up to 20 degrees out in the worst circumstances.
To check this, it is required to remove No 1 spark plug and rotate the engine (using some form of probe down the cylinder), to ascertain if No 1 piston and the indicated TDC timing marks do actually align as indicated TDC on your pulley.
Especially if your engine is other than the std. production one in the std. production vehicle it was originally fitted to.
If your indicated TDC pulley (reference) mark is wrong, then all you do and all we advise, will never stand a chance of achieving what's expected. This also applies to the information given above, so ignore this section at your peril.

There is a good check list for the distributors above and the following advice is also useful.

Its also worth noting that the best ignition timing in any given engine, is to achieve the most advance it can tolerate without pinking. ( Audible pre-ignition).
This is achieved by setting your V8 timing to about 4 deg. BTDC (assuming you've been through the distributor check list completely). Then tighten the distributor so that you can (with effort) still turn it by hand. ideally put a tip-ex mark or small scratch on the distributor body and engine block to record this spot.
Next road test the car and simulate high load by quickly shifting into a high gear or if Auto allow to change quickly up to 3rd or 4th Ideally you need to find a small hill or incline, now if you apply full throttle the engine should respond without pinking, find a safe place to pull over, open the bonnet and turn the distributor through a couple of degrees only, anticlockwise, this will add slightly more advance timing and if you do the same test, and repeat it until pinking is noticed you will be very close to your absolute best timing criteria
So now all you need to do is turn the distributor clockwise by the same amount by an amount to counteract the last adjust, retest for the absence of pinking and that the job done, you will have just achieved the best maximum timing position for your car

Having done this an ideal engine would run perfect in all areas and pull as you would expect from all load and rpm areas. you would also expect the final timing position to be somewhere close to 6-8 deg. btdc, (exceptions assumed) However if this is not the case and or your engine developers other strange habits then it is almost certainly pointing to another issue with your engine of which there can be many.

Fuel pump low pressure
Leaky older or high miles injectors
Poor or pretending plug wires
Flashy plugs that ar'nt so flashy after all :-)
Throttle pot settings
Air flow meter settings
Coolant and fuel temp sensors
Lambda probe(s) if any
Distributor ability, both its output voltage and mechanical advance systems capability

to name but a few. !!!!!

Don't worry though, most have few issues that cause problems, albiet all have issues that hold back what's easily & potentially possible

For the records and the benefit of this advice I must assume the engine is in (known and not assumed) great mechanical shape,

Earlier single points systems

Early Rover Single points system. Apart from being very inefficient in the first instance, the single points and most of the electronic systems are all now suffering from failing mechanical and vacuum advance systems and excessive component and shaft wear. The effect of this will, of course, be to produce poor spark intensity and erratic spark timing (not the best recipe for an efficient engine). Many customers think they have rectified, or can rectify these problems by fitting an after-market 'add on' electronic ignition (such as Luminition), but as this still employs the original distributor with its ageing mechanical components with their age-related wear and tear problems, and cost almost as much as a complete brand new Mallory replacement distributor, this is a false economy.

Later electronic systems

Later version original equipment electronic ignition systems offer a significant improvement on the earlier single points type distributor, however most of these have now become quite antiquated, and suffer severely from all the same and familiar mechanical problems. And in addition too they have introduced their own additional weaknesses anD problems experienced on the fine wire connections to the magnetic trigger pick-up head, and soldered printed circuit board connections. These failings are caused, and further agitated by, the constant and extreme changes of air temperature/humidity encountered in the stifled proximity of an engine bay. (after a time, continuous heat expansion causes fractures in the wiring and/or the PCB board).

Lucas 'Opus system 35DE8, used '76 through '82 with its amplifier and circuitry mounted internally, this system has produced the most problems with complete failure of ignition sparks, but problems normally lasts many months as the engine will normally re-start and behave again for some time. The failure is temperature related and can normally be identified by observing the rev counter because it will fail at the same instance due to loss of signal from the distributor.

Lucas 'Limb' system 35DM8, used '83 to '84 this system has the main circuitry and amplifier mounted behind the coil, the amplifier has a semicircular recess for the coil to mount on, the problems of this unit are similar to that of the 35DE8

RPi are pleased to anounce that we have some repaired distributors available œPOA, & used with our power amp described below are one of the better options available.

Lucas 'Limb' system 35DLM8, used 1985 on and is identifiable by having its amplifier miniaturized and mounted onto the outside of the distributor body (a small black box with two lucar terminals).

Some pictures to help further, pay attention to the wiring types used, as this is the easiest way to distinguish them.
35DMA 35DLM8 Lucas Opus
Lucas 'Limb' system 35DM8 Lucas 'Limb' system 35DLM8 Lucas 'Opus' system 35DE8

The Later type 1996 or newer is not shown above but the descriptions and pictures should help you identify what you have.

RPi exclusive A&R Power amps

Bigger Sparks, Maximum power & efficiency potential, especailly when upgrading other areas.

Our exclusive A&R Power amp increases spark output from 35KV +/- (stock new) to near-on 50 KV, & with Magnecore leads, this is all the ignition power you will ever need.

If your engine already has one of the later type electronic ignitions and its mechanical and vacuum advance systems are in perfect working order (many aren't, so please check.), then we offer a new ignition spark amp system that's sure to maximize your fuel and power returns, can be used with all std. electronic ignition types except the early Lucas Opus system 35DE8. For LPG users. Check out this info on our Dual timing LPG Version) (click here) (don't forget to press your Browser return button if you want to come back here).

V8 Ignition Hand-built Power amps. & (Dual Timing) versions also
available for LPG.
Hand built A amp {short description of image}
Small on the outside, Big on Power on the inside. Installation is less than 30 mins. without any experience.

A & R Amp Dyno Testing April 2002.

The following update was sent in by Ray Web at V8 Developments, testing our A&R amp on a Non LPG 3.5 rebuilt engine on their up-to-date engine Dyno facilities.

I quote, 'The Dyno tests of the power amplifier / A&R. unit proved very positive, four back to back dyno runs showed your A&R unit gained approx. 5BHP and 5ft/lb across the mid and upper rev range. Not only was this a better performance result, the engine seemed to be a lot easier to start, idled better and at lower revs, was much smoother through the rev range, and all in all made the engine sound a lot 'sweeter'. powergraph below.

Note how the gains go way beyond mere power gains, in themselves pretty impressive for an Ignition amp alone.
Distributor-less systems "Gems"

Distributor-less systems 'Gems'

The latest generation of Rover V8 engines have no distributor at all, the system uses magnetic trigger from the flywheel and, with 8 separate coils, is the ultimate in spark management. The 'Gems' type also uses the vehicle's own ECU to provide the perfect timing advance mapped to the engine's load and cruise driving requirements. Like re-mapping the fuel system, when you are in control of the spark management, some significant gains in engine efficiency & power will be attained.
(see Gems re-chipping details)

Mallory Dual point systems

Mallory Dual Point system.

Malory Dual point  Mallory Unalite 

The Mallory Unalite and Dual point as fitted to the Rover V8

We can easily understand that you may say, 'But, all that extra maintenance'. Not so, As the voltage is shared equally by two sets of points, we have found that they can last at least 4 times as long as conventional points system. A life span of up to 20,000 miles is possible. And at least when it does need a service, it's far cheaper than the electronic systems. (Normally needing a complete and very expensive replacement when faulty) & as this was designed originally as a performance upgrade, the Mallory Dual point distributor offers far better performance than std. electronic distributors, and for LPG use the extra ignition advance available from this distributor will give your LPG engine much better efficiency.

Apart from the more obvious and detailed advantages, a Mallory Dual point or Unalite distributor offers a unique adjustable advance curve provision that can easily be precisely matched to your engine's requirements, and by utilizing the 10 deg. additional dwell made available with a twin points system, resultant and significant increases of ignition dwell further increase charge time available to the coil, thus creating the best possible spark intensity and producing the best and most efficient possible combustion process for your engine.

The use of an appropriate Mallory distributor, with our recommended coil and ballast resistor is guaranteed to gain significant power, low-end and mid-range torque and efficiency and economy increases or we will provide a full money back guarantee promise subject to the following conditions.

Because we have fitted and supplied in excess of 1000 Mallory distributors we further advise the following.

Notwithstanding the above claims, on higher mileage or poor condition engines the Mallory ignition or any ignition improvement can highlight problems not previously apparent with your engine, due to camshaft wear, poor ignition, camshaft timing and fuel settings.

Carburetted (V8) vehicles can utilize the Mallory Dual point, however the Mallory Unalite is the required system for fuel injection engines.

Mallory Dual Point specifications œPOA inc. coil and Ballast resistor can increase coil output by 50%, and even at 7500rpm the Mallory gives you 20,000 volts from a stock coil - 10,000 more than conventional single points systems. Mallory build their distributors with stabilized points to eliminate float and bounce, brass case corrosion resistance, self lubricating bushings and a super duty cap and rotor to prevent shorting. You can also internally adjust advance 16 to 28deg.

Mallory Unalite (electronic) systems

Mallory Unalite Electronic system.

Because the Mallory Dual point system is not appropriate for the later EFi Rover engines, the Mallory Unalite offers the complete answer for those wanting the best possible aftermarket replacement ignition. Built to the same high mechanical standards of the Mallory dual point, the Unalite is an upgrade that is guaranteed to save fuel and boost power.

Mallory Unalite or Magnetic specifications œPOA inc. coil & ballast resistor gives you accurate maintenance free engine timing. Instead of the conventional points, the Unalite has a Photo-optic LED triggering system that never varies or wears out. You get increased rpm potential, improved combustion, longer spark plug life and improved cold weather starting. Connecting is a simple three wire hook up. The mechanics of the unit are the same high standard as the Dual point.

Mallory FAQ pages
Mallory" and other Customer Comments

Upgrading Ignition systems for LPG use.

Upgrading Ignition systems for LPG use.

{short description of image}

Magnecor leads allow the Sparks to get through like no other. "Click"

{short description of image}LPG is now becoming one of the most popular fuel choices for the Rover V8 engine and some quite interesting advantages are available from upgrading the ignition system.

{short description of image}As modern fuels are now very low octane, most std. vehicle ignition systems run with minimal ignition advance, since the days of 5 star fuel, std. ignition systems have been designed for far less timing advance.

.{short description of image}LPG is 112 octane, the extra 8deg or so advance available from the Mallory systems, or 14 from our power amp, can be put to very good use as the spark intensity is almost doubled in both cases.

{short description of image}Thus the slower burning characteristics of LPG can be overcome, indeed whilst most say using LPG loses power, this need not be true when other subtle upgrades such as this are employed.

Never underestimate the quality of std., O/E, or High street spec. ignition.

A typical e-mail quote. Thank you for helping me sort out my misfire problem with the amplifier. You may recall when we spoke that I said that the misfire was when on LPG when the engine was cold. You recommended fitting Magnecor leads as well, but as I had new Lucas leads fitted, I said that I would try them out with the amplifier first. The result is the engine is sweet as a nut when cold and a definite improvement in power and fuel consumption.

I am very pleased with it and will be recommending other gas users I speak to. Yours sincerely Peter Monday

Customer Comments

{short description of image} Ignition Amp ( A&R)

I just had fitted your advance unit for the gas. I rang earlier last week because I didn't understand parts of the instructions, and you said any ideas to make the instructions better would be welcomed. 1. where the 2 wires go into the dizzy there is no pos. or neg. on left or right hole it took a while to work it out. Showing which was which would be a big help, left is pos. as you know. My friend John fitted it and it is a definite improvement in power. I have the RP4 cam, duplex timing chain & new tappets & it goes very well.
I would like to say thanks for your help as it has made a world of difference the power & smoothness are excellent.
Alan Lambert

{short description of image} Timing pointer error.

Hi Chris and Lisa, we checked the TDC on the new engine and it was out of line with the stock marks. The stock timing mark was off by 10 degrees relative to TDC of the number 1 cylinder, so we have the timing correct now at 7 degrees.
Ron Sosnowski Coronado, CA

{short description of image} More timing pointer error.

G'day Chris,
I'm glad you raised the timing issue, I did sort out the relationship between true TDC and the timing marks on the pulley, tipp-ex time.

Martin G. Software Engineer Raytheon Australia P/L.

links to other component pages
[ V8 engine and component information and pricing ] [ Carburetion & fuel Injection ] [ Back to:Electrical ]
[ Transmission 2wd & 4wd ] [ Suspension, Handling,Tyres, Wheels & Brakes ] [ Stainless & Mildsteel Exhaust systems ]

Prices do not include local EU.Tax.(VAT).
Prices & stock are subject to change without notice. Information and advice, as always, is free.

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