What does the Ignition Amp do?
Discussion
hi chaps
Search facility is tatered (again) so a question for the clever ones of us.
After a 'stuttering' type intermittent fault and eventually a complete failure of the spark, I initially replaced the coil and king lead, which seemed to cure the fault but after a few hundred more miles had a complete engine shutdown.
I replaced the ignition amp (ignition module?) on the side of the dizzy and have now done another couple of hundred miles without a glitch but I want to test the old ign amp to see if it was that.
Can someone tell me
a) what they actually do
b) can they be tested
c) are they affected by heat - so should I be considering moving mine from the side of the dizzy to somewhere else like I suspect the later cars had done
d) can they be circumvented to limp home?
As usual, your invaluable help would be most appreciated.
Ta.
Ian
T
Search facility is tatered (again) so a question for the clever ones of us.
After a 'stuttering' type intermittent fault and eventually a complete failure of the spark, I initially replaced the coil and king lead, which seemed to cure the fault but after a few hundred more miles had a complete engine shutdown.
I replaced the ignition amp (ignition module?) on the side of the dizzy and have now done another couple of hundred miles without a glitch but I want to test the old ign amp to see if it was that.
Can someone tell me
a) what they actually do
b) can they be tested
c) are they affected by heat - so should I be considering moving mine from the side of the dizzy to somewhere else like I suspect the later cars had done
d) can they be circumvented to limp home?
As usual, your invaluable help would be most appreciated.
Ta.
Ian
T
Barreti said:
hi chaps
Search facility is tatered (again) so a question for the clever ones of us.
After a 'stuttering' type intermittent fault and eventually a complete failure of the spark, I initially replaced the coil and king lead, which seemed to cure the fault but after a few hundred more miles had a complete engine shutdown.
I replaced the ignition amp (ignition module?) on the side of the dizzy and have now done another couple of hundred miles without a glitch but I want to test the old ign amp to see if it was that.
Can someone tell me
a) what they actually do
b) can they be tested
c) are they affected by heat - so should I be considering moving mine from the side of the dizzy to somewhere else like I suspect the later cars had done
d) can they be circumvented to limp home?
As usual, your invaluable help would be most appreciated.
Ta.
Ian
T
Be interested in the outcome, not what it does, but if it's cured the issue. Mine has the same but now it's completely dead so not sure if its the same but used to cut out a fair bit. Sometimes it was a fuse in the footwell (initially) and then it just cut out, but would restart. When you restart did it struggle to idle?Search facility is tatered (again) so a question for the clever ones of us.
After a 'stuttering' type intermittent fault and eventually a complete failure of the spark, I initially replaced the coil and king lead, which seemed to cure the fault but after a few hundred more miles had a complete engine shutdown.
I replaced the ignition amp (ignition module?) on the side of the dizzy and have now done another couple of hundred miles without a glitch but I want to test the old ign amp to see if it was that.
Can someone tell me
a) what they actually do
b) can they be tested
c) are they affected by heat - so should I be considering moving mine from the side of the dizzy to somewhere else like I suspect the later cars had done
d) can they be circumvented to limp home?
As usual, your invaluable help would be most appreciated.
Ta.
Ian
T
FFG
FlipFlopGriff said:
When you restart did it struggle to idle?
FFG
No. ran as normal, and with the new king lead and coil seemed a different car altogether.FFG
I don't think it was the 'hot start' problem either as I understand the engine doesn't turn over if thats the problem whereas mine turned over but wouldn't make any effort to 'catch'
It was also not affected by throttle position.
Although I cleaned up the front, rear, centre console and wishbone earth points over the winter I do have a secondary earth cable already. Fitted to one of the bolts holding the removable chassis bar and one of the swirl pot bracket bolts.
Sorry to hear one of your Griffs is dead mate. Hope it gets sorted quickly and if there is anything I can do to help please ask.
Edited by Barreti on Tuesday 16th June 15:33
a) what they actually do
Switches the coil, take the place of the points in older days.
b) can they be tested
Don't think so, obviously by swapping out.
c) are they affected by heat - so should I be considering moving mine from the side of the dizzy to somewhere else like I suspect the later cars had done
Yes! They can be cooked!
d) can they be circumvented to limp home?
Wouldn't have thought so,it's needed to switch the coil.
Barreti said:
Can someone tell me
a) what they actually do
They turn the signal from the distributor (an induced current through Hall Effect via a toothed wheel and proximity sensor) into a switched signal capable of inducing HT in the coil.a) what they actually do
Barreti said:
b) can they be tested
Probably could be bench tested, but generally test by substitution is easiest.Barreti said:
c) are they affected by heat - so should I be considering moving mine from the side of the dizzy to somewhere else like I suspect the later cars had done
Yes. They should always be fitted with heat conducting paste between the amp and the heat sink to which they're mounted.Barreti said:
d) can they be circumvented to limp home?
Don't think so. Removal, cooling and refitting with new heat conducting paste might work though.Thanks for the information chaps. I think I'm getting the hang of it.
Dizzy turns and activates the electronic version of points which sends out a signal, amp turns signal into something the coil understands, coil generates spark.
So the amp is just a sort of babelfish?
Have I got it?
What is the conductive paste mentioned and anybody know where I can get some?
As I've just plonked the spare unit in I think I should pull it off, clean everything, put some new paste in and refit - yes?
Ant - I know you've replaced your engine bay loom, was this to fit coil packs instead of the dizzy?
If it was, just how much work is involved, what was the driving force behind the decision to do it, and what was the very ballpark figures for £'s and hours to do it if someone competent was to do it themselves (ie. Me)
Dizzy turns and activates the electronic version of points which sends out a signal, amp turns signal into something the coil understands, coil generates spark.
So the amp is just a sort of babelfish?
Have I got it?
What is the conductive paste mentioned and anybody know where I can get some?
As I've just plonked the spare unit in I think I should pull it off, clean everything, put some new paste in and refit - yes?
Ant - I know you've replaced your engine bay loom, was this to fit coil packs instead of the dizzy?
If it was, just how much work is involved, what was the driving force behind the decision to do it, and what was the very ballpark figures for £'s and hours to do it if someone competent was to do it themselves (ie. Me)
Barreti said:
Thanks for the information chaps. I think I'm getting the hang of it.
Dizzy turns and activates the electronic version of points which sends out a signal, amp turns signal into something the coil understands, coil generates spark.
So the amp is just a sort of babelfish?
Have I got it?
What is the conductive paste mentioned and anybody know where I can get some?
As I've just plonked the spare unit in I think I should pull it off, clean everything, put some new paste in and refit - yes?
Ant - I know you've replaced your engine bay loom, was this to fit coil packs instead of the dizzy?
If it was, just how much work is involved, what was the driving force behind the decision to do it, and what was the very ballpark figures for £'s and hours to do it if someone competent was to do it themselves (ie. Me)
The paste is heatsink paste, available from RS, Maplin , any electronics outlet.Dizzy turns and activates the electronic version of points which sends out a signal, amp turns signal into something the coil understands, coil generates spark.
So the amp is just a sort of babelfish?
Have I got it?
What is the conductive paste mentioned and anybody know where I can get some?
As I've just plonked the spare unit in I think I should pull it off, clean everything, put some new paste in and refit - yes?
Ant - I know you've replaced your engine bay loom, was this to fit coil packs instead of the dizzy?
If it was, just how much work is involved, what was the driving force behind the decision to do it, and what was the very ballpark figures for £'s and hours to do it if someone competent was to do it themselves (ie. Me)
My engine loom change was due to the change of ECU. So now on Emerald, no dizzy,amp, coil,otter switch.......
That will be heat sink paste,I know RS Components do it in a tube seem to recall its quite cheap 
Yes the modules are sensitive to heat,they usually start to mis-fire and then pack up altogether when the car has been stopped and then you come to restart it as the heat in the engine bay has built up when the car has been stationary with the engine switched off.Had no end of trouble when I used to build HOT RODS due to under bonnet temperatures.I ended up changing to a different type of module altogether and repositioned it inside the car on the bulkhead problem solved.
Oh forgot to say the Hot Rods had 4.0 litre rover V8s in them TUNED OF Course! You could always change to a Mallory Dizzy several versions available to fit the Rover V8
G.M

Yes the modules are sensitive to heat,they usually start to mis-fire and then pack up altogether when the car has been stopped and then you come to restart it as the heat in the engine bay has built up when the car has been stationary with the engine switched off.Had no end of trouble when I used to build HOT RODS due to under bonnet temperatures.I ended up changing to a different type of module altogether and repositioned it inside the car on the bulkhead problem solved.
Oh forgot to say the Hot Rods had 4.0 litre rover V8s in them TUNED OF Course! You could always change to a Mallory Dizzy several versions available to fit the Rover V8
G.M
Edited by Green Meanie on Tuesday 16th June 19:12
O.T.
).
Can anyone tell me which type of Mallory I should get, as there are several dfferent types that fit?
Green Meanie said:
...You could always change to a Mallory Dizzy several versions available to fit the Rover V8
G.M
I've been thinking of doing this as I keep goosing rotor arms and caps (on my third set in 2k miles G.M
).Can anyone tell me which type of Mallory I should get, as there are several dfferent types that fit?
I used the Mallory dual point dizzy,on one of my Hot Rods but the points needed checking and setting on a regular basis but did the job OK.Some of my fellow Hot Rodders had the fully electronic one but I do not have any knowledge of how good/bad this type was and my experience is about 7 to 8 years ago so maybe things have moved on from then.
Check the RPI Engineering(used to be RPI International) website the have a section on ignition upgrades,and discuss the pro and cons of different systems seems they like the Mallory dual point system and supply a Kit including coil and ballast resistor.
G.M
Check the RPI Engineering(used to be RPI International) website the have a section on ignition upgrades,and discuss the pro and cons of different systems seems they like the Mallory dual point system and supply a Kit including coil and ballast resistor.
G.M
Edited by Green Meanie on Tuesday 16th June 21:38
Oh, good point Bruce, thanks 
One other thing, the spare amp I used came off a 500 and included the bracket and the cable with the big connector with the metal clip you need to squeeze to fit it.
I understand the 500's have the amp mounted remote from the dizzy - I guess because of heat problems.
Can someone tell me where it is fitted on the 500
And does anyone have a spare of the other small cable which would plug into the side of the dizzy where my amp currently is - or tell me if/where I can get one.
One other thing, the spare amp I used came off a 500 and included the bracket and the cable with the big connector with the metal clip you need to squeeze to fit it.
I understand the 500's have the amp mounted remote from the dizzy - I guess because of heat problems.
Can someone tell me where it is fitted on the 500
And does anyone have a spare of the other small cable which would plug into the side of the dizzy where my amp currently is - or tell me if/where I can get one.
Hedgehopper said:
Decided I should buy an amp for my spares kit. Is it a TVR part or just a standard Rover fitting (from Halfords etc.)?
My original unit is sitting on the lounge table, but I know its a unipart part.I'll get the part number tonight and if we cross reference it with Lucas DAB118 that 5.0ltr has we'll know we have the right bit.
Edited by Barreti on Wednesday 17th June 11:27
Gassing Station | Griffith | Top of Page | What's New | My Stuff


