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MG Midget and Sprite Technical - Timing Headache

The engine is 1275 bored out to around 1330. The head is an MG Metro head, cr unknown. Cam is also unknown although reputed to be 731. Originally DCOE45 carburation but just fitted an HIF44.

My problem is what to do about timing. The dizzy fitted is a 20 deg max advance without vacuum. If I set this to an advance of around 5 deg the tickover is poor and there is a lot of shuttling on the transmission below 2000 rpm. If I increase the advance to 10 deg the engine revs increase at tickover, the shuttling decreases significantly but the engine has a tendency to run on. No pinking.

I have tried a standard 1275 dizzy with vacuum and static set to 5 deg and there is significant pinking particularly at around 2/2500 revs.

My problem is how to spec a dizzy if I'm not sure of the engine spec in the first place. Also, is say 12 deg static with a dizzy with 20 deg mechanical advance (so 32 deg in all), likely to be "right"?

I am wondering whether an electronic controller is the way to go as if I decide to change the cam (731 not an ideal) then I can accommodate a new timing profile.

Comments appreciated.
G Williams

This probably won't help and can't say with your engine and dizzy, but set mine up yesterday as per recommendations from this BBS
1330cc with a played around with Hif44. Kent 276 cam 123 dizzy. We didn't look at the setting but assumed 30 degree max advance and . we set the it 7 deg static and it started on the button.
G Lazarus

Gary: it starts on the button but I just think it could feel better on the road. It's the light throttle which could feel better, although I know that's an unfamiliar term to you and you probably won't have investegated that area of performance.
What su needle are you using?

Just in time for the Bridges Run then!
G Williams

I run 10.8:1 CR with a flowed head larger inlet valves. The dizzy is a non vacuum one. On the RR it was happy at 7 deg static or 13 deg@1000 RPM. max advance is 32deg@ 5000 rpm. I don't get any pinking or run on but use octane booster. I am running twin HS2's. Cam is equivalent to the old 2A 948 so (same exhaust period but slight less inlet) but with higher lift. I originally did experience a bit of hesitation around 2000 rpm but a change of needles on the RR cured it. I wonder if you need to put it on the rollers again?
Bob Beaumont

Bob: not been on rollers. I have only owned the Frog for a couple of weeks and after the intial "sh*********t!" of the effect with the Weber if I put my foot down over 3000 rpm, I began to realise that the setup was great for putting your foot down not good for modern traffic.
G Williams

The only sure way is to put it on rollers with a tuner with experience of these type of engines. Then take note of all the settings.
HALL JOHN

Gary, I feel you've not tried enough combinations with the set up you have - there's a hell of a lot of adjustment between static 5 and 10 degrees btdc. Note that others have had successes at static 7 btdc. There's a lot to be said for an afternoon of road testing, making very small adjustments between each test - some of the older distributors had a vernier adjustment which made things easier once you got close to the best compromise - but it's rare to get perfect town driving and perfect open road driving with a hot camshaft hence the big manufactuers move to VVT technology and electronic ignition.
Nick Nakorn

as said earlier and also in your carb thread, just get it onto a rolling road and set up properly and professionally. No amount of fiddling and guessing will have more than the remotest chance of hitting the right combination of spark and mixture, and you risk doing expensive damage in the medium term.
David Smith

Spending a dime to call peter burguss might be the best investment

Peter has a rolling road and sells 123 and 123 tune, what great about peter if you buy from him, his customer service blows out the factory plus he knows more then all of us combined...it might cost a couple of dollars, but it will be done right the 1st timeand no on going hassle

Good luck...they can be trying

Prop
Prop and the Blackhole Midget

David, I'm not in agreement that the alternative to a rolling road (or dyno) is fiddling and guessing. Assuming everything is in reasonable condition, there are plenty of SU needle charts to get within the ball park for a (say, for example) 'fast road' or 'stage 1' engine and adusting between extremes of rich and weak mixtures at idle or low unloaded throttle can be done by 'ear'. Ignition timing likewise - that 'tight' sound of too much advance and the no-power but loose feel of a retarded ignition; the almost pinking (but not quite) on a slow open throttle, when you're near the most advance you can set without damage, and so-on. All those sensory clues can get you very close to the best setting. On one's own car, you have the opportunity to test on regular trips over the same terrain as well. A methodical iterative process and using one's senses can make a massive difference.
Nick Nakorn

Running on is usually associated with the timing too retarded at idle and/or idle speed too high.

Nick, may I suggest you advise one should aim for the minimum advance without damage wot not just advice on part throttle? Modern rolling roads give a lot of feedback to help tune an engine. Even if one tunes to perfection on the road, you would only know if you 'got it right' having a run or two on the rollers. Folk have got close using g-techs and afr monitors and a lot of road testing. In 27 years of running the rolling road I can only think of about 4 occasions when I couldn't improve the power output. How do you control the iterative process?



Peter
Peter Burgess Tuning

I agree with Nick! For me, there are simply too many variables to fine tune as per instructions or whatever. The fine tuning is largely down to trial and error.

I would suggest though that timing is the very last thing to adjust. Plenty of other factors could feasibly cause the symptoms you are witnessing. Again, personally, I have found that valve clearances are far more important than first thought, that mix setting is crucial, that needle size with a HIF 44 - I use standard Metro - is a factor, and that all unions and joints to do with the carb MUST be air tight, that vac advance works etc etc.

If after all that, if it still runs not quite sweet, then armed with trusty 7/16 ths for the distributor clamp, find a hill and rotate CCW/CW accordingly. I have 123 set at 30 degrees position 5 - I think - as a start point, and take it from there. Very simple to effect.

It is all a compromise though. Again, personally I much prefer low end grunt over top end revving the nuts off it, and the ability to cruise along in 5th - up a hill! - is most satisfactory.

I too used get running on now and then - caused by the engine simply running hot under normal load - all other things being equal - such a the obvious plugs, coolant, valve clearancess - I would suggest you adjust the mix - enrich it incrementally...
Mark O

Nick, fine for you I'm sure - but we are talking here of unknown CR, unknown cam, unsure capacity, and an OP who isn't too confident in the circumstances. I'm just saying how I see the specific situation.
David Smith

David S

The variables you describe represent all the more reason to go with an iterative method rather than a definitive one. In addition, rotating the distributor body a tad CCW/CW is hardly rocket science.



Mark O

I am afraid I have to agree with Prop on this, get yourself and the Midget to a rolling road (Peter's).
I would also say that the 123 tune is superb. Only one moving part so no wear and the advance curve can be set via a pc to almost whatever you wish it to be. Peter has experience of doing this and all the kit needed. Once set up correctly, my car idles smoothly and runs very, very well.
Peter Burgess supplied the dizzy and did the tuning on his rolling road. Well worth the trip up the M1.

Dave
Dave Brown

Peter,
I entirely agree that a rolling road session with an expert will produce better results and I'll certainly head your way when I can afford it. But I was not suggesting otherwise. I was also not suggesting my examples were exclusive of other factors or situations, I was giving examples - I simply wanted to ensure that readers here on very limited budgets (such as myself, I'm sure others will be strapped for cash too) know that one can get an engine running reasonably sweetly (won't be max hosepower but that is not an important measure for most people) with minimal aids from technology. I'm all for Rolling Roads and Dynos and I'm also all for basic tuning by ear and road-test; the former might get perfection but the latter gets you day-to-day usability.
Nick
Nick Nakorn

or, the former gives guaranteed results while the latter risks wrecking a newly-built engine. I am speaking from experience, and I repeat, in this particular case from the OP's questions so far I deduce he does not have the level of experience or confidence that Nick has.
David Smith

unless a trailer is available the car will have to be set about right to drive it to Peter's

but once at Peter's you'll regret having not taken it there sooner - excellent value and quality work

plus you'll get accurate figures
Nigel Atkins

....and for those of us some hundreds of miles away from any such rolling roads and rapidly developing the locals' desire for thrift - DIY is an infinitely preferable option. I also have to take issue with the risks involved. Provided one does not do anything seriously dumb, the liklihood of wrecking an engine via timing adjustments alone is pretty remote. The A series is a numb beast and can take a good deal of hammer - modded or not.
Mark O

Or we do have rolling roads in Kent other than the scenic ones but first there are issues with the engine to sort.
Alan
Alan Anstead

not all rolling road tuners charge hundreds of pounds to sort road cars

when I went to Peter's I included it in a trip north so it only added a few extra miles

Mark,
the locals may have encouraged you further but I get the impression your tightness was already well developed ;)
Nigel Atkins

not sure where you are Mark as Grampian was abolished in 1996 but I believe Wallace performance still have a rolling road in Aberdeen (well they did last year at least). There's Ricky Gauld in Huntly too.
David Smith

David: I'm 67 and have been working on my own vehicles since I passed my driving test at 17. I know my way around conventional engine setups reasonably well and don't lack confidence. I haven't worked with non-standard engines I have to say and am happy to admit my ignorance in how standard components need to be adjusted or replaced to suit.

This particular engine has a number of issues, not least unknown spec, dubious timing marks, and rocker assembly in pretty poor state. All I know is it's "about 1330cc and may have a 731". It has been professionally rebuilt and balanced by Searles so hopefully the core is ok.

With the Weber fitted it was a nightmare and as I said before I have replaced that with an HIF. With the Weber it ran on sufficiently to allow time to get back in the car and put it in gear! I was also very poor below 3000 rpm.I have two distributors but neither seem to achieve even adequate running conditions and without trying to alter the internal springs and cams (and to what?) I am limited to what I can do, short term - essentially play around with static setting and connect/disconnect the vacuum.
Since the stock dizzy doesn't do the job, the engine spec is obviously having an influence and knowing which way to go with this is my problem. If I need to replace the dizzy, I don't want to risk buying the wrong one.. but which is the right one?

I agree with Mark - I didn't think engines were that likely to be seriously damaged by timing being out by a few degrees. Continuous pinking is going to do some damage, so is running too weak, but this thread does rather come across as "beware, you ARE going to break it.... unless you use a rolling road".

Breaking news: going programmable. That way I can flex the settings whatever the spec.

G Williams

from original post - >>Comments appreciated.<<

should be edited to >>Not all comments appreciated.<<

:D
Nigel Atkins

""beware, you ARE going to break it.... unless you use a rolling road"."
Now you're simply making stuff up unnecessarily. So you are far more experienced and confident than I inferred from your original post. That's good, you press on, I'm only suggesting what I would do in your position based on my own experience. I used to think the same as you but in the last 15 years have used 5 different rolling roads for a variety of road and race cars. They all improved matters far quicker than I could have done by trial and error, and were therefore judged good value for money. I don't think I've spent more than 100 quid per session unless I've bought parts as well. Works for me but we're all different, it's not a problem.
David Smith

I can resist it no more, it's too good an opportunity to pass up - David and I agree :D

(and not for the first time but I've been too shy to mention it before :) )
Nigel Atkins

As I get older (57 this year)I cannot hear detonation. I can see the power effects on the rolling road but still have someone with 'good ears' listen for pinking. On a tuned engine the margin of safety is less than for a standard engine, if there are any standard, untouched, engines left?

Once I discovered rolling roads I realised how crap I was at guessing settings. Typically, unless something is poorly in the engine, timing is down to within a degree for best results. The effects of needing different degrees at different rpms will be very difficult to obtain on the road as a linear curve may not work best and the temptation is to copy some sort of linear curve.

As a point of interest, I attach a graph of an MGB with an odd problem. I use the brakes on the car to drop the speed prior to a power run. This particular car gave varying power curves for no obvious reason. In the end I had a guess at servo dragging....did runs with and without prior use of brakes and could obtain less measured at the wheels power if I used the brakes to srop speed to do an acceleration run....on the road, if one 'seat of the pants tuned' with accelerating runs and say a stop watch, there is a good chance one would use the brakes to slow the car prior to timing? At such point you are also measuring brake problems through transmission losses not just engine power differences.Graph shows subtle difference below 4500 rpm.

Dave Gollan who helps me with technical input and with writing the books spends hours road tuning his Harley with AFR recording(two pickups, one for each barrel for afr). Then he comes to the rollers and we alter settings a fair amount as it is difficult to control everything including safety on the open road.



Peter

Peter Burgess Tuning

Peter
There are also engine issues to resolve before a RR session. Cant make silk purse out of sows ear!
Alan
Alan Anstead

one for Peter B. . .what is the cost of a RR session. .can see the benefits, but an idea on the pounds shillings and pence would be handy
P Bentley

You can blame the website for geographical anomalies -strictly speaking I reside in Aberdeenshire, and being half Yorkshireman, yes Nigel as I have those well known inbred characteristics of short arms and deep pockets, thrift is somewhat easy for me to develop.

I think there is a bit of wood for trees blindness going on here. Like Nick, I think you can get very close using your ear and a bit of understanding. Once all other things are set correctly, timing can be set at static easily enough as a start point, dyanamic is set iteratively thereafter. Some wee marks on the distributor body and the block assist. If it pinks, retard it a smidge and try again. Decent timing is when pinking disappears, but at the slightest smidge of advance - it reappears. Mind, that said, a samll degree of pinking when giving it beans up a hill is acceptable. This is not that hard to accomplish, and of course, is a good educational start into the weird and wonderful world of Midget maintenance.

Good link here

http://classicmechanic.blogspot.co.uk/2011/05/ignition-timing-with-modern-fuels.html

Additionally I use the best petrol available and a dose of valvemaster.
Mark O

Hiya P Bentley

We charge £80 plus vat plus any bits such as plugs or needles, this can be up to three hours or more, we are very accommodating, Thursdays is chip day so you get those too if you stay long enough, otherwise a trip to Carol's Cafe is always highly recommended.

Mark," Mind, that said, a samll degree of pinking when giving it beans up a hill is acceptable." I cannot agree with you, define difference between small amount and large amount and, sadly, peak power usually way past by the time you get pinking, esp on road engines. It seems to me you reckon on as much advance as possible with/without a little pinking? This assumes a philosophy of best bhp coincides with as much advance as possible, not so, and I would query the base understanding you talk about. Same with fuelling, without measuring you do not know, even measuring afr can be misleading as the numbers folk tell you to get do not always give best power for a specific engine. I also questioned the OP with his concept of wrong jets for his large choked Weber on the fuelling thread, he had no base knowledge to go on , just what he read about smaller choked webers so I would say not a matter of wood for the trees. I think a few folk are, like myself, saying a little knowledge or even 'miss-knowledge' can lead one down very blind paths.

Peter
Peter Burgess Tuning

Peter

Why is a small degree of pinking unacceptable? No-one is saying let the thing knock about like a rabid woodpecker, rather if the timing is set on the cusp of pinking - as it ought to be - there will rare occassions when advance is such so as to incur it.

In addition, who says best bhp is best for me? - or anyone else for that matter? As aformentioned, I prefer low down torque - which may or may not co-incide with best bhp setting.

My wood for trees remark was directed at setting the timing and nothing else. I was merely emphasising the point that getting it pretty damn close is not difficult nor is it some black art confined to a rolling road emporium.
Mark O

Mark, I think there might be differences between engine types and makes concerning pinking. In my Morris Minor days I found that even tiny hints of pinking would lead very rapidly to head gasket problems yet, when working freelance for R. S. Williams, I was told that pinking when 'giving it the beans' as it were, was normal for the 5.3 litre V8 cars of 1980s vintage (new at the time!) and that no damage of any kind resulted from it. I was amazed, but all the experienced people in the workshop concurred that it was normal and fine for those particular engines while not at all for the 4 litre in-line 6 cylinders. But with the advent of more sophisticated diagnostic equipment and mappable ignition, I suspect that such compromises are no longer required or factory-approved - Peter might be able to shed some light on this.
Nick Nakorn

It's all getting a bit "edgy". Let me try and clarify.

I am not against the use of Rolling Roads per se. However, as Alan (Anstead) said when he spent half a day with me, "Someone with a rolling road wouldn't look at this in this state". As it is running at the moment, I wouldn't get to the rolling road!

I am just trying to get it runnable as there is a very obvious timing issue. I can't assume that the dizzy fitted is the correct one for the car and unfortunately I don't know the car spec so can't select the correct one either. It seems to need a lot of low revs advance and really that was the core of my question - was that normal for a non-standard cam? The downside of a lot of low revs advance is that at the top end, adding the mechanical advance to a high static causes the pinking. So should I go for a dizzy with less mechanical range, or keep turning the static setting down?

Meanwhile, I have compression readings of 210 psi suggesting a high compression ratio but what exactly?
The rockers have a lot of side float, leading to questionable repeatability of valve settings.
Unknown camshaft
Untried carburettor.
Questionable tdc setting (I am more confident in this now although a lot of the above could cause that to be questioned).

I need to start somewhere and don't really want to pull the engine out to investigate the unknowns although that would be the ideal approach. I am of the Mark/Nick school of thought that I should be able to get it to a drivable state using observation and adjustments and THEN polish it on the rr.

Surely doing that sort of tweaking is what the hobby is all about!



G Williams

Hi Mark

You seem to think best bhp is on the cusp of detonation, this is not so and as such is a harder point to derive from road tuning. Getting it to pink or just about is easy but will not be the best setting, just easy to achieve on the road. We set the engines for best power at all rpms not just max power, dyno samples at some ridiculous rate and gives lots of info. When we tune a car we swing the dizzy and take power readings, if the curve is correct one obtains the best bhp at all rpms, if the curve is too long or short we can only achieve max bhp potential at say low or high rpm, at which point I set it to suit the customer as long as the settings are safe and try and get the customer to get the dizzy re curved or buy another one armed with the info from the rolling road. Then free retest with new/recurved distributor. For best low end torque run your tappets as loose as you dare without hammering the valve tips....if you run off the opening/closing ramp you can put a lot of stress on the rocker and valve tip. Loose tappets trap more air and fuel in at low rpms thus boosting torque at low rpms.

Hi Nick

The pinking, if short lived should be ok for road and even for sprint but not prolonged hard use. I would say, if the V8s had the correct advance curve they would not detonate. Sounds like putting up with wrong dizzy for the use. With race cars we even reduce CR on individual cylinders (usually no 4 with a 4 cyl)to prevent pinking. I agree with you, A series do tend to eat gaskets and ex valves if not set correctly.

Peter
Peter Burgess Tuning

cheers for the info Pb from Pb !
P Bentley

GW - Firstly I would sort all other issues affecting engine performance. It is no use at all trying to mask these by fiddling about with timing. Timing should be the last thing to fiddle with. Even so, yes, anyone with a smatterring of ICE knowlegde should be able to get spot on static and even closer on dynamic after a few runs up and down your local hill.

PBT - Power is not necessarily what I desire. I much prefer "driveability" which seems to be on the cusp of pinking and involves torque. I have tried all curves on the 123 at 30 deg advance - no real difference - and as it such a hassle using the tiny cross screw, fiddled with advance by rotating the body and road tested up the hill. I guess this is essentially what you do - except you produce a chart -I use my ears and speedo.

Granted I could go to a RR and as GW states, polish the results, but I reckon I am pretty close to optimum setting on current dizzy after some exhaustive testing. For sure you guys would save all of this in the first place and probably get it spot on more or less first time - that is where you score -but for me, fiddling about and the subsequent knowledge gained is all part of the hobby
Mark O

max bhp everywhere same as max torque everywhere. Torque and bhp related by rpm and constant so max torque at all rpms same as getting max power at all rpms.

To give you an idea, I attach a graph of a midget. The distributor curve was too long. With best advance at low rpms there was too much high rpm advance and it killed the power(dark red lines). The advance that gave best top end power was killing the bottom end power (blue lines) I sent the car out on the orange line for safety. The owner is going to make a little sleeve to put over the spring post the anvil touches on max advance to reduce max advance. We will then run the car up again and all should be OK. This took an hour and a half testing whilst setting the Weber etc etc. We are looking to make the curves a combination of red for low rpms and blue for above 3500 rpm, will be even quicker on sprints then. Would have been easier with a 123 as we could have chosen a shorter curve more easily. Max advance for best power was 26 degrees, the red line with the poor max power was 30 degrees max advance.

Peter

Peter Burgess Tuning

please note that Peter put £80 plus VAT and not £80 per hour (plus VAT) as others charge

I think a reasonably competent and experienced home mechanic (so that excludes me) with a reasonably standard engine and ancillaries can using some basic figures as a rough starting point can set up the timing by ear and road tests to have the engine running reasonably well

as we all know these engines in reasonably standard form will run for a long time without serious detriment even if poorly set up and maintained, they won’t be running at their best of course but the type of owner that does this thinks they’re near enough


Mark,
I’m not sure how to go about this with a man of your nurtured tightness so I’ll just ask what best petrol available you can get and which Valvemaster do you use (assuming you have an unleaded head)?
Nigel Atkins

Hello G.

Not to be insulting, but no one has mentioned it as of yet.

But have you tried to time it from the other side of the rpm scale

Run the engine up to around 4200 - 4500rpm and set the dissy at 28 - 32 degrees

Im not a fan of listening to time an engine, I perfer to blink really fast while watching the timining marks...but thats just me

Prop
Prop and the Blackhole Midget

Btw... you mentioned it had a weber, if this is the newer ones, from what ive read, they have problems right out of the box, appeartly there made in china and dont play well with the orginal webbers of years ago

FYI

Prop
Prop and the Blackhole Midget

Nigel

Up here in the tundra, it is super unleaded. Valvemaster is the one with the green cap - I think - nothing special, indeed have been running about without it for a while now - seems fine.

I think you can do a little better with your timing. Stick some wee graduations on a piece of sticky paper/tape - attach to block opposite dizzy body and turn ccw or cw noting performance at each graduation. If it drops off, or starts to pink, turn it back one increment. Even better if you have vernier adjustment.

Yes it takes time, yes it takes a few miles to establish exactly how the engine performs and under varying circumstances, but it does provide good empirical data and a sound incontravertial understanding of just how your engine is behaving. Of course, don't do any other mods whilst all this is going on!

PBT

Your chart illustrates the point I was making. Advance curve for the hashed red line which seems to indicate best torque at low rpm - I like that - is not necessarily the best curve for top end bhp - which I don't care about as I don't race around Knockhill every week. It is all a compromise. Interestingly at about 3500 rpm - the top end at which I change gear and thus more or less the highest rpm at which I drive normally, all curves appear to offer similar characteristics.
Mark O

Mark, the setting for best low rpm torque would have killed the engine at above 3500 rpm. The point I was trying to make is, by actually measuring quantitatively the effects of different timing one can build up an accurate timing curve required. There is no compromise when you set the curve properly, I was illustrating effects of wrong advance curve on power/torque output and how to move forwards with the engine I tested. I can see I cannot sway you away from the concept of on the road does the same job. The problem customers have, they tell me, trying to do it on the road, is accurate timing and repeat performance timing to actually get better than a 'bulk' near enough seat of the pants feel. You can and have drawn conclusions from the three graph lines I posted, I reckon you could not have produced anything like that for road testing even with afr monitoring and gtech to try and time the acceleration runs.

As an aside, the max torque obtained on the three lines I posted was with the timing set for best power above 3500, this would have given the best 0-60 acceleration times, even though poorer below 3500rpm. The best performance will be achieved with a shorter advance curve as I said in my post accompanying the graph.

Enjoy the road tuning and if you ever get down this way have a run on the rollers and see how close you have got, at which point I would very happily say you had done a great job or you may have to say you were close but no coconut :)

Peter
Peter Burgess Tuning

PBT - I have no doubt you could improve on my current timing - but to what degree and whether I could accept any difference in - for want of better terms - the driveability of the car - is the debate here. For thsoe with little time to fiddle about and perhaps limited knowlegde, RR is quite probably the better option, but, and in the interests of sharing knowledge on internet forums, and enjoying what is essentially a hobby - there is more than one way of skinning a cat. In addition, imparting a little knowledge to fellow Midget drivers is not a bad thing....folk may learn something - which is always good.
Mark O

Mark, $64000 dollar question. If you owned a rolling road would you tune your car with it or do it on the road?

Peter
Peter Burgess Tuning

Use it of course....but I don't have one, and even if I did, it would not come for free. Guess I'd have to generate business to fund it....
Mark O

:) I don't think my dyno will ever pay for itself, I must be the worlds worst business man, but I can look in the mirror knowing I haven't poohed on anyone!

Peter
Peter Burgess Tuning

Mark,
boy are you a guarded person, which super unleaded 97, 98 or 99? and which Valvemaster has a green top I don't know I don't use the stuff you did

don't worry about compromising yourself I've already seen your name on various victim lists for the government, DVLA and "them" :)

as you've already found you might have been wasting your money by using the Valvemaster, money out of your long pockets!

I can't remember what compression your engine is but you might be able to say money on petrol, depending on what super unleaded you currently use
Nigel Atkins

Well that all sounds good....you got to admit, that blinking eye trick I mentioned earlier, is very orginal... and its totally free

Imagine the possibilities...some say revolutionary, others others may even call it evolutionary....I say its just a blinking great idea

Prop
Prop and the Blackhole Midget

Nigel

Not guarded at all - I honestly don't know the octane rating. Shell super unleaded - the only one within about 30 miles and the garage only has 3 tpyes of fuel - four if you count the peat - so I am somewhat limited.

Valvemaster - I disagree. A splash now and then aids valve life and keeps them free of crud, but yes, I tend not to follow instruction on its use to the letter, principally as I don't get really pinking or any drop in performance otherwise, and the head is unleaded.
Mark O

super unleaded is normally 97 octane, 97 octane is more expensive, Shell V-Power Nitro+ is 99 octane and more expensive still

why not save money and run on the less expensive 95 or even 97 (both still rip off price because of taxes and petrol companies and their subsidiaries, sub-contract employees, etc.,)

you also put that you've been running fine without using the Valvemaster and you don't use it as directed by the manufacturer anyway, so you seem conflicted about its use, bit like only taking vitamin supplements now and again or following your horoscope only now and again

you don't need the lead replacement and you don't need the octane boost so why are you throwing your money at it, just think of the money you've already wasted, on second thoughts no don't

my car is set up for 95 octane but I run it on almost exclusively Tesco Momentum99 (99 octane) for its package of cleaning additives and of course placebo effect - yes I too am a conflicted person
Nigel Atkins

PBT, I'm pretty confident that my skills on the road test quest are no where near as good as your skills on the rolling road...

oh rolling road...
take me home...
to the place....
where I belong........

Virginia Water...

I'm a sucker for graphs..
Nick Nakorn

"oh rolling road...
take me home...
to the place....
where I belong........""

Yeah.... now lets all go smoke some pot and fly some non tested expermential light airplanes and see how that works out for us

Prop
Prop and the Blackhole Midget

Prop

I've tried blinking, but I can't seem to do it fast enough!
Dave O'Neill2

Hi Nick

I ended up putting a blob of weld on the edge of the anvil in the distributor and filed it back till the max advance looked about right, time will tell when we get it back on the rollers. I will then print you a new graph off of the results .

Peter
Peter Burgess Tuning

Something else to peruse

http://www.csi-ignition.nl/bestanden/article_miniworld_nov_2012.pdf

The Swifttune curves, as one would expect, are for race/rally spec engines

http://www.minispares.com/article/Technical~Information/Electrics/New~CSI~electronic~ignition~distributors.aspx?22f56378-e9db-4f9e-824e-9ac72ea62b00a8007ee5-137f-4da3-820a-caea3e5d48c888d784cc-4e83-4746-a650-8c4f957b7e6e

CSI also do a Spridget distributor
Motley 5

This thread was discussed between 27/04/2014 and 01/05/2014

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