Hi everyone....I have posted this on aurlo but am hoping for some help off outers... I am seeking some suggestions on how to eliminate a small but annoying problem on my 77 that has me all but buggered on how to fix it..
Let me explain..
I have owned my rangie for 8 years and I know it pretty well... It was running a stroked P76 with the original manifold and twin carb set up with electronic ignition..(The elec ignition was done by a auto elec.. It runs an MSD Blaster to coil with Bosch fuel module.) It ran great but needed better carburation to maximise its performance so the time came 1 year and a 1/2 ago to upgrade the manifold to custom Willpower Manifold and upgrade the carbs to Holley Projection...
Now I will state the holley projection came off a donour car that had a worked 4ltr rover in it and ran like a cut snake... Amazing..
So one weekend we installed the manifold and projection and got it all running... New fuel lines etc etc... On instalation we noticed we had a high rpm miss.. Ran great at start up and id throttle but when we gased it it developed a very bad miss.... Let the games begin.. So far I have done the following to try and get rid of it..
Step 1.... (basic electrical)
All new plugs and gap checked to correct gap 28 thow
Timing set at 6 degree BTDC
Leads and coil leads all new 8mm
New dizzy cap...
At this point I took it to Carb N Ject in Brisbane to help eliminate the problem. The car sat in their shed for 2 weeks and when I went to pick it up the guys said to me to just rip out the pos Holley Proejction and replace with a carb... He said that he had changed the plugs.. (They were new) charged me $50 for doing sweet FA and wasting my time and said come back in the new year as he was shutting for Christmas...
* Didn't go back and told all my race car mates not to go back either! Arrogant pigs..
So teh problem was back to me... Next stop..
Step 2... (Possible fuel issues, over or under fueling..)
New inline fuel filters
New Fuel pump
New EFI hoses
New return hose to larger diam return pipe in tank
New custom swirl pot and primer pump
Step 3... (Possible fuel pressure regulator isues..)
Fuel presure regulator check.. all good set book spec to 15 -18psi
Lamda sensor up its bum to check styrometric pressue. All good. Perfect even..
N.B. We did manage to improve but not eliminate the miss by upping the regulator pressure to 25psi but the system is not designed for such high psi.. Problem still existed..
Step 4... (Losing spark maybe???)
Coil wiring changed to run constant 12v. Was previosuly 12v on start up then 9v which is the pre elec ignition arrangement... Now constant 12v. Also gave the projection a constant 12v spark from the battery rather than any piggybacks.. Check ohms to the TPS and all set to book spec.
Step 5...(Holley Projection is the problem??)
Much research was done regarding the holley projection as seeing as though all else was proving fruitless I figured it must be the projection.. It starts first go, gets me 16ltr to the 100k and is as crisp as but at full open noise no go.. so I bought myself a BRAND NEW Holley Truck Avanger 670cfm carb..... Pulled out the HP, fuel lines, pump etc and did the conversion to the carb... All new lines etc etc..new linkages..new throttle cable bla bla bal.. Started her up first go..adjusted choke, idle and bowl settings and mixtures... Took the old girl for a blat around the block.... SAME PROBLEM EXISTS....... (*&^(*&^RK!!!!! Thats a day and $800 down the drain..
Step 6.. ( HPgoesback on)
As the truck avenger didn't solve my problem I removed it (Ran in the car for 15mins) Anyone chasing a brand new carb cheap? and re-installed the projection.. New hoses back except this time I didn't bother with re-installing the swirl pot etc as it just doesn't need that much fuel. With al the new adjustments and changes it runs sooo sweeet but open throttle is still a joke...
Step 7....
I have bought a brand new coil and ignition module but as yet have not installed it... The previous coil and module wouldn't be 5000kms old but I thought maybe having the coil only getting 9v after start up may have upset either item so I will install new module first and then if still no luck I will do the coil...
Step 8...
The only thing I have left is the dizzy.. It has no slop in the shaft and on elec igntion there is bugger all in them to go wrong.. I have cleaned the unit and checked the vac advance is working all ok.. It is.. I have also checked for vacuum leaks using some aerostart etc but without any leaks found. As the missing issue is only under load and not idle I believe it is a spark isue rather than a fueling issue...
The questions.. What next..
Could the MSD coil have too much spark???
Is the dizy stuffed...???
Could the ignition module be wrongly matched to the coil...??
As these were fitted to the vehicle by a auto leckie I am guessing no...
Any help would be of huge assistance.. A match and some fuel has already been suggested! I am prepared to listen to all suggestions but please note the Holley Projection was replaced with a brand new carby and teh problem remained so it isnlt the projection unit.. They do seem to have a bad name butits not it...
Merry Christmas..
Geothro
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Electrical Conundrum???
Moderator: Micka
Holy crap...you already used most of my first thoughts...
That said, the MSD ignition systems are infinitely more powerful than any OEM units, but I could not see that having too much spark would be the problem. But then again...we are all dealing with Rovers so we know not to rule ANYTHING out.
We ran an MSD ignition unit on our rock crawling buggy(3.9V8) with an MSD Rev limiter with a Gas Research custom set up and had zero issues with spark. If there was going to be an issue with too much spark, then it would more likely happen with ~130 octane pure propane than 91octane ULP.
We did have some issues wiring up the MSD intitially though, now that I think about it - was 3 years ago - and we ended up calling the info hot line for eith MSD or Summit Racing who we bought it off.
The only suggestion tnat I would put forward is ditch the HP and go with straight gas. Much simpler. Much more reliable. And NO fuel delivery problems whatsoever.
Best of luck mate.
Micka
That said, the MSD ignition systems are infinitely more powerful than any OEM units, but I could not see that having too much spark would be the problem. But then again...we are all dealing with Rovers so we know not to rule ANYTHING out.
We ran an MSD ignition unit on our rock crawling buggy(3.9V8) with an MSD Rev limiter with a Gas Research custom set up and had zero issues with spark. If there was going to be an issue with too much spark, then it would more likely happen with ~130 octane pure propane than 91octane ULP.
We did have some issues wiring up the MSD intitially though, now that I think about it - was 3 years ago - and we ended up calling the info hot line for eith MSD or Summit Racing who we bought it off.
The only suggestion tnat I would put forward is ditch the HP and go with straight gas. Much simpler. Much more reliable. And NO fuel delivery problems whatsoever.
Best of luck mate.
Micka
Going by what you have said i would have guessed that it may have been a fuel pressure issue but as you said you changed the projection to a carb so you would have ran a low pressure pump on the carb which would cancell out the high pressure fuel.
Was the car running the same dizzy coil set up before the projection was put on? if so i would gather it had zero problems untill the projection went on.
Was the car running the same dizzy coil set up before the projection was put on? if so i would gather it had zero problems untill the projection went on.
elec grmlin
THANKs Micka.. gas is just a whole new deal and no god for what I do... But thanks for your email...
Nottie... your first point i correct.. When I went back to the carby I was running a holley blue stock fuel pump with an inline regulator (and without) set at 7psi which is what holley reccomend for their truck carb...
Your second point s also correct. Previously the car ran the 5ltr and twin rangie carbs with the same existing electronic set up... Nothing changed. However as the original carbs and manifold had the engine weezing for breath "perhaps" the problem existe but wasn't evident due to the engines inability to get enough HP output. Now that it has the mumbo maybe it is exposing a pre-exisitng problem..
Dunno...
All good suggestions...keep em coming!
Geothro!
Nottie... your first point i correct.. When I went back to the carby I was running a holley blue stock fuel pump with an inline regulator (and without) set at 7psi which is what holley reccomend for their truck carb...
Your second point s also correct. Previously the car ran the 5ltr and twin rangie carbs with the same existing electronic set up... Nothing changed. However as the original carbs and manifold had the engine weezing for breath "perhaps" the problem existe but wasn't evident due to the engines inability to get enough HP output. Now that it has the mumbo maybe it is exposing a pre-exisitng problem..
Dunno...
All good suggestions...keep em coming!
Geothro!
timing
Timing... I have played with timimg without great sucess.. It doesn't feel like a timing problem though based on teh size of the miss... Under full pedal it will drop most cylinders....
A dyno is A GREAT idea but as you would have read its hard to find anyone who is willing to give it any time unless your a ricer with bolt on mods... I race Cobras and even with the race car and all the guys I race against we find it very hard to get good professional and well priced srvice. I can tell you some horror stories about dyno shops and 10K race cars...
The stock injectors on the HP are rated to 670cfm.... The carb also was rated to such a cfm and with the same problem it can't be injectors...
Sadly enough!
A dyno is A GREAT idea but as you would have read its hard to find anyone who is willing to give it any time unless your a ricer with bolt on mods... I race Cobras and even with the race car and all the guys I race against we find it very hard to get good professional and well priced srvice. I can tell you some horror stories about dyno shops and 10K race cars...
The stock injectors on the HP are rated to 670cfm.... The carb also was rated to such a cfm and with the same problem it can't be injectors...
Sadly enough!
SO you can be pretty sure its ignition related!!!!!!!
First I agree with Nottie to try a standard ign set up. What do you have ? If you have a electronic dizzy try that with the standard amplifier and coil.
If you have points trggering the MSD just try another dizzy.
If no good you have found that it is the MSD.
Just one from left field. if you have fitted a bosch alternator , it is known for the hash to cause a miss in Rover V8 ignitions/injection.
The fix is to move the signal wire away from the alternator, or to fit shielded wire earthed at both ends.
Regards Philip A
First I agree with Nottie to try a standard ign set up. What do you have ? If you have a electronic dizzy try that with the standard amplifier and coil.
If you have points trggering the MSD just try another dizzy.
If no good you have found that it is the MSD.
Just one from left field. if you have fitted a bosch alternator , it is known for the hash to cause a miss in Rover V8 ignitions/injection.
The fix is to move the signal wire away from the alternator, or to fit shielded wire earthed at both ends.
Regards Philip A
dizzy
Nottie, my thoughts precisely.. I have access to an electronic ignition set up from a 3.9 which I will need to mod to fit mine so I plan on trying that one next next week.... I actually plan to do this prior to trying the new module and coil as I have spent enough on parts already only to find it isn't what I'd hoped... So as there is $200 in those parts alone I'm trying the diz first...
PhillipA, thanks for the heads up... I can't tell you exactly what ignition I have at this stage as the ignition set up came with the stroked motor. I have also read in old TORQUE articles about the hash problem.. Can you explain a little further re-signal wire issues.. That being on the pics I have seen indicating this problem the alternator is on the passenger side adjacent the diz whereis with mine the alt is on the drivers side far away from the diz so I am wondering if this could be an issue?? I'll try anything though!
Sorry for the laymens question.. but I while I may sound like I have good knolwedge everything thus far has been learnt as matter of progress rather than exisiting knowledge..
ThanKS again to all so far who hve chimed in to help me...
Mat T
PhillipA, thanks for the heads up... I can't tell you exactly what ignition I have at this stage as the ignition set up came with the stroked motor. I have also read in old TORQUE articles about the hash problem.. Can you explain a little further re-signal wire issues.. That being on the pics I have seen indicating this problem the alternator is on the passenger side adjacent the diz whereis with mine the alt is on the drivers side far away from the diz so I am wondering if this could be an issue?? I'll try anything though!
Sorry for the laymens question.. but I while I may sound like I have good knolwedge everything thus far has been learnt as matter of progress rather than exisiting knowledge..
ThanKS again to all so far who hve chimed in to help me...
Mat T
It should not be a problem if teh alternator is on the RH. It's only wher ethe signal wire goes over the top of the alternator.
So it's your ignition somewhere.
BTW, check that you have a "LUCAS" rotor. Aftermarket ones have a bad but deserved reputation for shorts to the shaft. Even though the Lucas is $40 and the aftermarket is $10, its worth the money.
Regard sPhilip A
So it's your ignition somewhere.
BTW, check that you have a "LUCAS" rotor. Aftermarket ones have a bad but deserved reputation for shorts to the shaft. Even though the Lucas is $40 and the aftermarket is $10, its worth the money.
Regard sPhilip A
Update
Well, the latest... I took my car for the looong drive up to my mates house (simo) for some more feedback on what he thought it may be.. This is what we discovered..
1. Timing is set at 9 degree BTDC and vac advance is working OK
2. We removed the MSD Blaster Coil and swapped it with a std 12v old dirty one from his old parts bin and the car seemed to run better but certainly didn't eliminate the problem at all. I think this was becuse the blastr coil and ignition module aren't compatable???
3. We changed the ignition module to a brand new one to ensure this wasn't the problem. No change was evident.
4. We did reduce the timing to about 6 degrees but the car ran worse and it is now back to 9..
I also contacted the manufacturer of WillPower Manifolds and we had a lengthy discussion regarding the problem. His input and help has been great and he is a gentleman in trying to help me sought the drama. He suggested removing the vac advance... Now this manifold is a single plane highrise type and I beleive it still has alot to do with spark. My reasons for this are...
On the holley projection unit you have 5 manual adjustments with tuning.
1 - Choke - Adjusts warm up compensation for different engine requirements during cold start and engine warm up.
MINE IS SET TO +/- 0.
2 - Accel Pump - Allows fine tuning of the accelerator pump shot for different engine requirements. Turn knob clockwise to
increase pump shot, turn counterclockwise to decrease.
MINE IS SET TO +1.
3 - Idle Trim - Fine adjustment of idle fuel, specifically below 1000 RPM. Turn the knob clockwise to richen the fuel
mixture, and counterclockwise to lean the fuel mixture.
MINE IS SET TO +/- 0.
4 - Main Jet - This knob allows adjustment of the entire fuel map, either richer or leaner, just as changing main jets in a
carburetor would do. Turn the adjustment knob clockwise to add fuel, or turn the knob counterclockwise to
remove fuel.
MINE IS SET TO +2
5 - Hi-RPM Jet - This knob allows adjustment of the fuel delivery above 3000 RPM. Turn knob clockwise for additional fuel
above 3000 RPM, or counterclockwise to remove fuel above 3000 RPM.
MINE IS SET TO -5.
I believe the obvious issue HI RPM jet is set to -5 as it is overfueling. The problem becomes way more obvious the closer the dial goes to towards + so for me this suggests that it is getting too much fuel at hi rpm. Now as the fuel is regulated at 15psi and plugs are black and sooty it tends to lead me to think the ignition isn't producing enough spark to burn. It's obviously working very well at idle an anything under 3000rpm but once loaded up the car is overfueling... These is my thoughts however Im happy to hear what others may make of this..
My next plan is to borrow an aftermarket high energy ignition set up like a CRANE Hi6 igntion which gives a big spark and remove the std igntion module and coil just to see if it is a spark issue at those higehr rpm.....I also pln on getting the dizzy overhauled just to check it also....
Welcome your thoughts...
MATT
1. Timing is set at 9 degree BTDC and vac advance is working OK
2. We removed the MSD Blaster Coil and swapped it with a std 12v old dirty one from his old parts bin and the car seemed to run better but certainly didn't eliminate the problem at all. I think this was becuse the blastr coil and ignition module aren't compatable???
3. We changed the ignition module to a brand new one to ensure this wasn't the problem. No change was evident.
4. We did reduce the timing to about 6 degrees but the car ran worse and it is now back to 9..
I also contacted the manufacturer of WillPower Manifolds and we had a lengthy discussion regarding the problem. His input and help has been great and he is a gentleman in trying to help me sought the drama. He suggested removing the vac advance... Now this manifold is a single plane highrise type and I beleive it still has alot to do with spark. My reasons for this are...
On the holley projection unit you have 5 manual adjustments with tuning.
1 - Choke - Adjusts warm up compensation for different engine requirements during cold start and engine warm up.
MINE IS SET TO +/- 0.
2 - Accel Pump - Allows fine tuning of the accelerator pump shot for different engine requirements. Turn knob clockwise to
increase pump shot, turn counterclockwise to decrease.
MINE IS SET TO +1.
3 - Idle Trim - Fine adjustment of idle fuel, specifically below 1000 RPM. Turn the knob clockwise to richen the fuel
mixture, and counterclockwise to lean the fuel mixture.
MINE IS SET TO +/- 0.
4 - Main Jet - This knob allows adjustment of the entire fuel map, either richer or leaner, just as changing main jets in a
carburetor would do. Turn the adjustment knob clockwise to add fuel, or turn the knob counterclockwise to
remove fuel.
MINE IS SET TO +2
5 - Hi-RPM Jet - This knob allows adjustment of the fuel delivery above 3000 RPM. Turn knob clockwise for additional fuel
above 3000 RPM, or counterclockwise to remove fuel above 3000 RPM.
MINE IS SET TO -5.
I believe the obvious issue HI RPM jet is set to -5 as it is overfueling. The problem becomes way more obvious the closer the dial goes to towards + so for me this suggests that it is getting too much fuel at hi rpm. Now as the fuel is regulated at 15psi and plugs are black and sooty it tends to lead me to think the ignition isn't producing enough spark to burn. It's obviously working very well at idle an anything under 3000rpm but once loaded up the car is overfueling... These is my thoughts however Im happy to hear what others may make of this..
My next plan is to borrow an aftermarket high energy ignition set up like a CRANE Hi6 igntion which gives a big spark and remove the std igntion module and coil just to see if it is a spark issue at those higehr rpm.....I also pln on getting the dizzy overhauled just to check it also....
Welcome your thoughts...
MATT
You should really get a handle on what your mixtures are under load and at idle.
One way is to hire dyno time or to buy an NGK wide band sensor.
Petrol engines will tolerate a wide range of mixtures without much complaint. If theplugs are sooty it does suggest richness but most plugs will be sooty around town, you really have to do a cut.
A standard ignition should drive your engine at least up to 6-7K. Its not that exotic!!!!
When you talk of the" ignition module" what are you talking about? A Lucas module or aftermarket. Have you looked at the pulse generator in the dizzy?
Have you tried a known good complete ignition ie std dizzy and pickup, module and standard coil?
It seems to me that you have to be systematic to ID where the problem is.
Regard sPhilip A
One way is to hire dyno time or to buy an NGK wide band sensor.
Petrol engines will tolerate a wide range of mixtures without much complaint. If theplugs are sooty it does suggest richness but most plugs will be sooty around town, you really have to do a cut.
A standard ignition should drive your engine at least up to 6-7K. Its not that exotic!!!!
When you talk of the" ignition module" what are you talking about? A Lucas module or aftermarket. Have you looked at the pulse generator in the dizzy?
Have you tried a known good complete ignition ie std dizzy and pickup, module and standard coil?
It seems to me that you have to be systematic to ID where the problem is.
Regard sPhilip A
dyno
Phil, I hear you re: dyno... and if anyone can recommend someone in Bris or the Gold Coast who have a good reputation and willing to work on rangies then I have no problem going there... But dyno places and I to date have not had much luck...
I thought I was being fairly systematic with my approach slowly eliminating each area... The car used to run fine with the std ignition prior to the manifold install so what I have was doing the trick with old rngie carbs and stock manifold... The thing is the engine was built by a guy who used to build all the rover race engines in the UK for wolf racing or something so it isn't stock by a long way.. but what it is I dunno..
By igntion module I mean the standard ignition brain for teh diz to coil. It's a BIM 124 from memory which is a std early VK dunnydore or xp falcon. This is what the auto elec fitted up for the coil and elec diz so I can only presume it's correct..
Once I fit up a bigger spark module and if I have no luck I'll then pay more $'s and get the diz checked and calibrated...
After that.... dunno....
Matt
I thought I was being fairly systematic with my approach slowly eliminating each area... The car used to run fine with the std ignition prior to the manifold install so what I have was doing the trick with old rngie carbs and stock manifold... The thing is the engine was built by a guy who used to build all the rover race engines in the UK for wolf racing or something so it isn't stock by a long way.. but what it is I dunno..
By igntion module I mean the standard ignition brain for teh diz to coil. It's a BIM 124 from memory which is a std early VK dunnydore or xp falcon. This is what the auto elec fitted up for the coil and elec diz so I can only presume it's correct..
Once I fit up a bigger spark module and if I have no luck I'll then pay more $'s and get the diz checked and calibrated...
After that.... dunno....
Matt
have you gone colder range of spark plugs? you have changed every thing in the ing system but not said any thing about the plugs.
when you up the comp in a engine you need to go colder plugs.
i had this problem in a 355 stroker a few years ago when reving under load about 6000 rpm, did every thing you did then went a colder plug ( setting up for noz) and it went away. i ended up with a plug 3 heat range colder that the recommended peformance plug. on the plug the higer the number on the plug code the colder the heat range is.
when you up the comp in a engine you need to go colder plugs.
i had this problem in a 355 stroker a few years ago when reving under load about 6000 rpm, did every thing you did then went a colder plug ( setting up for noz) and it went away. i ended up with a plug 3 heat range colder that the recommended peformance plug. on the plug the higer the number on the plug code the colder the heat range is.
cheer up emo kid
PLUGS
Hmmm, thats an interesting one.... thanks for your response but as mentioned in my original topic the plugs where 1000k's old before being changed at Step 1 and again by the Dyno guy again before step 2..... It's had 3 sets of plugs in it!
Back to my drawing board... but thanks for your suggestion..
Back to my drawing board... but thanks for your suggestion..
if the heat range is out i won't matter how little k's the plugs have done, they wont work right
my car did less that 800k's and 2 sets of plugs in the time before i put the noz on. it was running about 10.5 comp. another thing i got heaps better k's out of a tank when i changed the plugs.
the tuner prob put the same heat or 1 set up in when you might need 3-4 or more steps up.
what is you comp and the plugs that are in the car now?
my car did less that 800k's and 2 sets of plugs in the time before i put the noz on. it was running about 10.5 comp. another thing i got heaps better k's out of a tank when i changed the plugs.
the tuner prob put the same heat or 1 set up in when you might need 3-4 or more steps up.
what is you comp and the plugs that are in the car now?
cheer up emo kid
update...
Well, I have managed to get off the www a vacuum line digram to ensure all was correct with my vac lines... and all is well... So...
next thing in my thought process was SPARK... so I hooked up a MSD Hi6 ignition system with MSD Blaster Coil just to eliminate any spark issue as the thing has 40million volts of spark... Absolutly no difference..... So all roads lead to either...
The dizzy.... however the vac advance and everything is working correctly.. OR
The WILLPOWER manifold.... Its a single plane manifold and the problem started when I fitted it so perhaps thats the issue... OR
Go against all my instincts and go back to the dyno shop and see how much money they can bleed me for......
Dunno..... the car runs sooooo wel until I give it the wellY!
next thing in my thought process was SPARK... so I hooked up a MSD Hi6 ignition system with MSD Blaster Coil just to eliminate any spark issue as the thing has 40million volts of spark... Absolutly no difference..... So all roads lead to either...
The dizzy.... however the vac advance and everything is working correctly.. OR
The WILLPOWER manifold.... Its a single plane manifold and the problem started when I fitted it so perhaps thats the issue... OR
Go against all my instincts and go back to the dyno shop and see how much money they can bleed me for......
Dunno..... the car runs sooooo wel until I give it the wellY!
Just reading this and mulling it over.
You've not mentioned checking the distributor advance only vacuum advance. The vacuum advance on the RV8 dizzy is more for overrun purposes and has little to no effect on the ignition timing at high RPM under load. At wide open throttle under load the vacuum in the plenum chamber is more or less atmospheric pressure, it really ramps up on overrun though so the vacuum advance is used to burn off excess fuel to prevent pops form the exhaust.
The ignition timing in these areas is determined mechanically by the weights inside the dizzy. My guess is you're simply not getting the advance you need at high RPM/loads because the weights are seized or otherwise limiting the advance.
Not enough advance will result in apparent overfueling. You're looking for at least 30 degrees advance in a high RPM/high load area although they also don't seem to like more than 35 degrees. The highest you'll see is around 40 degrees advance during overrun at very high RPM when the vacuum and mechanical advance combine.
One other thing I haven't seen mentioned, have you mechanically checked the timing or have you just used the pulley marks ? RV8s can have huge discrepancies between the marks on the pulley and the actual TDC so it's always worth pulling number 1 plug and checking the pulley mark is correct if you've not done it before.
You've not mentioned checking the distributor advance only vacuum advance. The vacuum advance on the RV8 dizzy is more for overrun purposes and has little to no effect on the ignition timing at high RPM under load. At wide open throttle under load the vacuum in the plenum chamber is more or less atmospheric pressure, it really ramps up on overrun though so the vacuum advance is used to burn off excess fuel to prevent pops form the exhaust.
The ignition timing in these areas is determined mechanically by the weights inside the dizzy. My guess is you're simply not getting the advance you need at high RPM/loads because the weights are seized or otherwise limiting the advance.
Not enough advance will result in apparent overfueling. You're looking for at least 30 degrees advance in a high RPM/high load area although they also don't seem to like more than 35 degrees. The highest you'll see is around 40 degrees advance during overrun at very high RPM when the vacuum and mechanical advance combine.
One other thing I haven't seen mentioned, have you mechanically checked the timing or have you just used the pulley marks ? RV8s can have huge discrepancies between the marks on the pulley and the actual TDC so it's always worth pulling number 1 plug and checking the pulley mark is correct if you've not done it before.
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I have seen this a couple of times, if your using a BIM024 module and you reverse the pick up wires to the module you get a high RPM miss, The original wiring has 2 different sized terminals so this can't happen. When you extend the wiring and use standard blades it's impossible to tell which way they should go.
Also if the wiring from the distributor pickup is running near the plug leads you can get interference which can cause double firing of the coil giving a miss also usually worse at higher RPM. My module is mounted near the coil and i had this problem. i rerouted the coil lead and it's been good ever since.
Hope this helps,
Brad
Also if the wiring from the distributor pickup is running near the plug leads you can get interference which can cause double firing of the coil giving a miss also usually worse at higher RPM. My module is mounted near the coil and i had this problem. i rerouted the coil lead and it's been good ever since.
Hope this helps,
Brad
Geez Brad that's a weird one! Firstly yes, I am running a BIM024 ignition module which is brand new. If I reversed the pickup wire +/- the car would run on maybe 4 cylinders..but not really... It wouldn't be anywhere near drivable that's for sure..
My +/- wiring from the diz runs a fair way away from the ignition leads but I coud extend them just to negate any cross firing possibilities....
I still thank the mechanical advance is the problem..... But thanks for the heads up!
Matt
My +/- wiring from the diz runs a fair way away from the ignition leads but I coud extend them just to negate any cross firing possibilities....
I still thank the mechanical advance is the problem..... But thanks for the heads up!
Matt
Sorry should have clarified, when you reverse the pickup wires it changes the timing, so you need reverse the wires and reset the base timing. As the signal from the inductive pickup is in a different spot. So the timing will be massively retarded or advanced can't remember which.geothro wrote:Geez Brad that's a weird one! Firstly yes, I am running a BIM024 ignition module which is brand new. If I reversed the pickup wire +/- the car would run on maybe 4 cylinders..but not really... It wouldn't be anywhere near drivable that's for sure..
Brad
Re: dixzzy
Dont go by the timing marks on the balancer ,as Davew said they have a tendency shift and also flog out the keyway which makes it impossible to time correctly using just the marks and a light.geothro wrote:Dave, I think you are spot on the money with teh dizzy weights...
I have checked the timing marks and all is sweet so me thinks I need to pull the diz and have it overhauled as you mentioned.....
Matt
Saddle up tonto, its the not so loanrangie! . 98 TDI DISCO lightly modded with more to come.
A HA!
Hey Brad, would yo mind telling me more about this BIM024 ignition module problem you have explained.. It's very interesting to me.. and I think you may be onto something... Let me explain. ON the BIM024 you have 4 spade outlets. - to coil + to coil/- to diz + to diz. So when I wired in the MSD HI6 Ignition and ran its respective - and + to the diz wires as connected to the BIM module it would fire, stutter and die.... (?) so i reversed the -/+ wires to the diz and it fired straight away. (N.B. I still had the same miss though even with this MSD set up) I then re-connected my old set up and ran those same wires as connected to the MSD to the BIM module and it ran on 4 cylinders if your lucky and died.. So in essence with the BIM024 module as connected + is X wire... whereas on the MSD setup the + wire is Y wire!!!! That can't be right and leads me to think your suggestion has a high degree of merit.
Thus I'd be keen to know how you came to know about this problem. My ignition and Module were set up by an auto electrician so I had no say as to its rightful installation BUT unless they had of rev'd its ring under load they'd have never of known there was a problem as under std driving it runs beaut ifully!!!
Matt
Thus I'd be keen to know how you came to know about this problem. My ignition and Module were set up by an auto electrician so I had no say as to its rightful installation BUT unless they had of rev'd its ring under load they'd have never of known there was a problem as under std driving it runs beaut ifully!!!
Matt
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