Nods news , Sorting out the rear bumper

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Re: Noddys Natterings ,That Garage

Post by bazzateer » Tue Aug 09, 2011 8:52 pm

That's Dilwynn's garage in Llanrug.
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Re: Noddys Natterings ,That Garage

Post by imp.sport » Thu Aug 11, 2011 1:02 pm

TomFox5150 wrote:Thats awesome! where is that?
Go to Google maps copy and paste this.... 53.146443,-4.181584

Go to street view where the green arrow is.
There's a few photos in there as well.
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Re: Noddys Natterings , Me and SU carbs

Post by Dave ' Linwood ' Lane » Fri Aug 19, 2011 4:36 pm

Many of you know im an advocate of SU carbs but this came about by accident and the transition was far from easy :roll:
Following on on from my 998 exploding years ago I fitted a temporary 875 which didnt like my 28/36 Weber off the 998 .
So Both cars at this point were running Solex carbs and were plodding on nicely
I happened apon a NOS twin SU inlet manifold by C @ T on ebay and managed to get it for pennys :D from there the experiment began.
I got a pair of seized knackered carbs from a local scrappys of a MK3 Spitfire that had been there so long it had snapped in half :o , I bought a rebuild kit from Burlen fuels and after much faffing about got stuff to actually move on the things.
At the time I knew no one in the club or any where else for that matter running twin SUs on an Imp but did find an old article recommending NO 1 needles and a red spring , good place to start I thought .
Well after fitting it did indeed run but not very well , in fact the Solex was better , I had massive issues with the choke set up and the throttle linkage plus still the wrong needles, I found a website called minty which did needle comparisons so plumped for a choice using an un-educated guess , I got it wrong 5 times in total which was quite a lot of money as needles are £20 a pair .
Not knowing exactly what I was doing didnt help but reading loads of stuff on the internet I soon fathomed out what to do and where I was going horribly wrong.
In all it took 3 months of playing about with needles , different damper oil , balancing and just experimenting to get get it running nicely , added to this there was very little space for air filters so I made my own by cutting down some old K @ N filters
I did all this on the Vusky as the engine was not very good and running it weak or rich wasnt going to harm an already borked engine much anyway.
Ive learned shedloads since those early days and being self taught ( no one to ask :cry: ) ive managed to sort the Singer with a pair with comparative ease and the swap-over only took a couple of days to fit and set up correctly .
So far from plain sailing but worth it in the end ,
I think theres 4 of us in the club running these carbs now , maybe I started something :lol: :lol:

Heres the Minty needle site
http://www.mintylamb.co.uk/suneedle/

And Burlen fuels
http://www.burlen.co.uk/
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Re: Noddys Natterings , Me and SU carbs

Post by bazzateer » Fri Aug 19, 2011 5:16 pm

At least 4 Dave, I'm sure there's many more either running them or, Like Tim, planning to. :D
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Re: Noddys Natterings , Me and SU carbs

Post by ChrisBenoy » Fri Aug 19, 2011 5:27 pm

I have to admit that if I wasn't able to get a 28/36 for my car or any future cars then an attempt at a pair of SUs would be my next choice. I've never used strommies but i've seen so many problems with them that I don't think i'd care for. I've got an adapter for a single Su on a solex manifold as well so may try that some time point.
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Re: Noddys Natterings , Me and SU carbs

Post by Dave ' Linwood ' Lane » Fri Aug 19, 2011 5:49 pm

If my 998 was still with us so would the 28/36 , The SUs were tried out of desperation , there had to be something better than a solex and more reliable than Strombergs and at the time cheap .
Finding that inlet manifold was the catalyst .
The Vusky still has the carbs from the snapped Spitfire and apart from a pair of " new type " needle valves , the odd tweak ( usually summer to winter and vise versa ) and a briefy experiment with different needles Ive not touched them in the 7 or so years theyve been on :D
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Re: Noddys Natterings , Me and SU carbs

Post by 617sqn » Fri Aug 19, 2011 7:21 pm

My ex-Slik50 budget saloons Rover SD1 V8 ran twin SU's. When the original race engine blew up ( a piston ring land gave way at walking pace, and bounced around the engine for a short while. Making a mess ), and following the ensuing re-build i decided to look into the set-up and bought an SU needles book from Southern Carbs. I plotted a number of needle dimensions on graph paper that looked promising and from the original engines' starting point I managed to find needles that offered a decent range of performance. When, for example, I found a small flat-spot at certain revs, it was feasible to look at the needle book, plot it on a new or existing graph and make direct comparisons. This method worked very well and helped produce a very tractable engine, with a 285 cam, that was easily capable of embarrassing the fuel injected Vitesse versions in straight fights.

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Re: Noddys Natterings , Me and SU carbs

Post by Prometheus » Fri Aug 19, 2011 7:33 pm

617sqn wrote:it was feasible to look at the needle book, plot it on a new or existing graph and make direct comparisons.
Use the linky that Dave posted :

Noddy wrote:Heres the Minty needle site
http://www.mintylamb.co.uk/suneedle/
saves paper and trees and ultimately the planet man :lol:
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Re: Noddys Natterings , Me and SU carbs

Post by 617sqn » Fri Aug 19, 2011 7:48 pm

/\ /\ Very good : Yeah, that would do it, but this was back in the day. When paper and killing trees was in vogue :lol:

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Re: Noddys Natterings , Me and SU carbs

Post by moose » Sat Aug 20, 2011 11:15 am

Ive not touched them in the 7 or so years theyve been on


poor maintenance regime there Mr Noddy, i thought you were beter than that :lol:
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Re: Noddys Natterings , Me and SU carbs

Post by bazzateer » Sat Aug 20, 2011 12:34 pm

I was told if you touch them you'll go blind! :lol:
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Re: Noddys Natterings , Me and SU carbs

Post by The Nun » Sat Aug 20, 2011 2:53 pm

moose wrote:Ive not touched them in the 7 or so years theyve been on


poor maintenance regime there Mr Noddy, i thought you were beter than that :lol:
Its no fun if it never goes wrong though, keeps you on your toes, especially if you end up walking.
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Re: Noddys Natterings , A bit of tuning

Post by Dave ' Linwood ' Lane » Wed Aug 31, 2011 4:36 pm

Ive been faffing around with the Vusky lately to see if theres any more umph to be had as its getting a bit tired .
Ive had a play with the advance curve on the dizzy by altering springs and weights using bits of a knackered sport dizzy and other stuff lying about , re timed it its going a lot lot better and is really revy ( Not technically done but a great way to learn )
Next step is to weaken the low end mixture a tiny bit and richen the mixture further up the rev range a tad as per the gastester at my friendly garage , using the chart i posted earlier on here ive picked and ordered a pair of needles , we shall see if its better or not once they arrive and are fitted .
Im Definitely heading in the right direction and hope to get further improvements with more tweaking
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Re: Noddys Natterings , A bit of tuning

Post by kilty » Wed Aug 31, 2011 4:51 pm

Nice one geez! Who needs rolling roads and mapped ignition eh!? :wink:
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Re: Noddys Natterings , A bit of tuning

Post by Lotus-e-Clan » Wed Aug 31, 2011 6:44 pm

And Noddy, just think what you could do with an on board wideband AFR meter....like file you own bespoke SU needle profile to give you the optimum AFRs across the rev range giving optimum torque/power, economy, cleaner oil, less bore wear etc.

I know the initial outlay is a bit high........ realistically about £200 -£300 for a complete kit(my TechEdge 2J2 system is currently about £250 from TriggerWheels)) but they are mashusively educational and transferable from car to car too. And with petrol so expensive ATM, a wideband set-up is only equivalent to three tanks of petrol or about one years insurance (money for nothing) for a modern!
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Re: Noddys Natterings , A bit of tuning

Post by Dave ' Linwood ' Lane » Wed Aug 31, 2011 7:26 pm

Great idea Pete , not sure my tired Vusky engine would benefit that much , I will pick your brains on this though , piccys of your setup might help and a how to , not up on this modern stuff TBH , I iz oldschool :lol:
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Re: Noddys Natterings , A bit of tuning

Post by Prometheus » Wed Aug 31, 2011 7:28 pm

Lotus-e-Clan wrote:And Noddy, just think what you could do with an on board wideband AFR meter....like file you own bespoke SU needle profile to give you the optimum AFRs across the rev range giving optimum torque/power, economy, cleaner oil, less bore wear etc.

I know the initial outlay is a bit high........ realistically about £200 -£300 for a complete kit(my TechEdge 2J2 system is currently about £250 from TriggerWheels)) but they are mashusively educational and transferable from car to car too. And with petrol so expensive ATM, a wideband set-up is only equivalent to three tanks of petrol or about one years insurance (money for nothing) for a modern!
This is what i'm seriously thinking about doing myself. It's very difficult to get the setting right when engine is not under load, plus i'm sure it would be great to be able to see how different terrain and even possibly climate effects the AFR as you drive.

Is it easy to install? The only thing that puts me off silly though it sounds is the ultra modern look of the gauges perhaps they do with old fashioned full face smiths type :lol: .

.
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Re: Noddys Natterings , A bit of tuning

Post by Prometheus » Wed Aug 31, 2011 7:29 pm

Noddy wrote:Great idea Pete , not sure my tired Vusky engine would benefit that much , I will pick your brains on this though , piccys of your setup might help and a how to , not up on this modern stuff TBH , I iz oldschool :lol:
Hey Dave maybe we could split the cost and take it in turns to use it :lol:

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Re: Noddys Natterings , A bit of tuning

Post by Dave ' Linwood ' Lane » Wed Aug 31, 2011 9:21 pm

This will now be my " Im miserable " picture , pinched from the Sherborne castle thread
Cheers Drew :lol: :lol:

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Re: Noddys Natterings , A bit of tuning

Post by Meltdown » Wed Aug 31, 2011 9:26 pm

/\/\That biscuit looks a bit soggy :lol:
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Re: Noddys Natterings , A bit of tuning

Post by Lotus-e-Clan » Wed Aug 31, 2011 10:01 pm

^^^ Crikey, that picture proves you are a dedicated follower of f..classic car shows!

Yeah I understand the reluctance to install a digital LED style 52 mm dial like the Techedge LA1 I have....my first Dynojet /Autometer installation (which proved unreliable) has a old school full scale "needle indicator" analogue 52 mm dial. I have been meaning to hook up the old school analogue Autometer dial to the Techedge 2J2 "ECU" which has a WB 0-5v analogue output suitable for external loggers and, apparently, moving coil dials.

The TechEdge LA1 digital LED 52 mm dial is in fact a "programmable serial device" and can display RPM, TPS (or MAP), AFR, direct and buffered Lambda, battery voltage, or any other configurable 0-5v "user" inputs like temp sensors or whatever and has a logger-trigger function too so it's not directly comparable to a simple AFR moving coil analogue dial (which is just a glorified volt meter). The serial cable to the 52mm LA1 dial doubles up as a serial input into a Laptop for logging purposes too.

So you could just buy the 2J2 wideband controller plus an O2 sensor & weldable exhaust boss and connect it up to your laptop and forget about a permanent dial for the time being (which reduces the outlay to £167) ...maybe buying a simple analogue Autometer (or other make) AFR dial if you want a simple reference to AFRs on the move at all times...which I recommend as the on-road data is VERY educational...knowledge IS power :wink: )
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Re: Noddys Natterings , A bit of tuning

Post by skamanfrank » Wed Aug 31, 2011 10:17 pm

I've been looking at Innovate LC1 wideband controllers, and have a plan for my own LCD gauge to display it on (top secret at the moment though ;) haha!) None of this tacky gauge stuff for me :P
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Re: Noddys Natterings , A bit of tuning

Post by Prometheus » Wed Aug 31, 2011 10:43 pm

skamanfrank wrote:I've been looking at Innovate LC1 wideband controllers, and have a plan for my own LCD gauge to display it on (top secret at the moment though ;) haha!) None of this tacky gauge stuff for me :P
Knowing you Frank it's probably going to be a head up display projected from behind the dash. Or perhaps you could get one of those monocles that apache pilots wear but cunningly disguised as a pair of funky shades :lol:
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Re: Noddys Natterings , A bit of tuning

Post by ImpManiac » Fri Sep 02, 2011 9:15 pm

...Innovate LC1 wideband controllers...
Yep. That's what I've got waiting to go on at some stage. :D I am not sure what type of gauge to use but I am not averse to a modern digital display in my car. But we'll see.

Very well done, Noddy! :mrgreen: You are a clever fellow and no mistake.

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Re: Noddys Natterings , A bit of tuning

Post by Dave ' Linwood ' Lane » Sat Sep 03, 2011 3:34 pm

Noddy wrote: Next step is to weaken the low end mixture a tiny bit and richen the mixture further up the rev range a tad
The new " educated guess " needles have now arrived and are fitted .
Ive been for a blast and it has indeed improved the top end , revs better and seems smoother and more responsive , Ive not fine tuned the mixture as ive no access to a gas tester ATM but im going to Thornfalcon car show tomorrow which is a 20 + mile blast on main roads , il check the plug colours when i get there and adjust if necessarily , then see what its like on the way home,
Still heading in the right direction :D :D
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Re: Noddys Natterings , A bit of tuning , new needles are in .

Post by kilty » Sat Sep 03, 2011 5:54 pm

8) I`ll bring the cookies Dave, leave the brolly at home it`s gonna be a dry one :roll:
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Re: Noddys Natterings , A bit of tuning , new needles are in .

Post by imp.sport » Mon Sep 12, 2011 2:25 pm

I noticed the word Imp associated with Noddy on another site.
Here :lol:
Well it raised a smile with me anyway 8)
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Re: Noddys Natterings , A bit of tuning , new needles are in .

Post by Dave ' Linwood ' Lane » Mon Sep 12, 2011 4:15 pm

^^^^^^^^^^^^^ :lol:
Especially as Ive got a Beemer although not one of those :)
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Re: Noddys Natterings , A bit of tuning , new needles are in .

Post by Dave ' Linwood ' Lane » Mon Sep 12, 2011 5:48 pm

Rolling road tomorrow for the Vusky :roll:
Standard new readings for a HC engine is
BHP gross 41.7 , net 39 @ 5000rpm
Max Torque net in lb ft is 52 or 7.1 in kg/m
Max BMEP is 147 lb.sq/in or 20.3 in kg/cm squared @ 2800RPM

SOOOOOOOOOOOOO , Whats the betting with an engine I built over 10 years ago with 70.000 miles added its half all that :lol: :lol: :lol:
Perhaps a guess from some as to just how worn my motor actually is :D
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Re: Noddys Natterings , A bit of tuning , new needles are in .

Post by ChrisBenoy » Mon Sep 12, 2011 6:16 pm

Depending on the RR it might even show as being about 50bhp, thats roughly what standard (even worn standard) imp engines seem to show these days.

Will be interesting to see though, it is a carefully tuned engine, rather than out and out power i'd expect to see a very flat curve with no dramatic shifts.
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Re: Noddys Natterings , A bit of tuning , new needles are in .

Post by Dave ' Linwood ' Lane » Mon Sep 12, 2011 7:04 pm

ChrisBenoy wrote: it is a carefully tuned engine, rather than out and out power i'd expect to see a very flat curve with no dramatic shifts.
Its only an L4 + 30 with a Janspeed small bore and twin SUs , its rather tired now and is not a lover of long hills any more , To be fair to it I built it 10 + years ago and it was my first total rebuild and apart from the odd stupid thing its been fine .
Untill the recent " there MUST be more power in there somewhere tuning frenzy " ive bacically left it alone .
So im guessing 35 ish :roll:
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Re: Noddys Natterings , Rolling road results

Post by Dave ' Linwood ' Lane » Tue Sep 13, 2011 1:07 pm

Just back from the Dyno test , not too bad really , mixtures a bit rich low down , then weaker mid range but all in all OK for an old engine.
51bhp @ 6000 RPM ( Didnt want to go any higher but it was still climbing )
46BHP @ the flywheel .
Not too bad for an L4 built by me over 10 years ago and only 4 less than a sport :o :D :D :D :D
Colours on the chart never came out so to make it clear
Top lines are Torque
Middle lines that run almost straight are BHP
Bottom lines are AFR
Could be tuned a bit better but good enough for me as im not racing it , its running well so il leave it alone now
One thing they did say BEFORE the test
If it starts running way too weak at any point we shut it down and wont continue past that point , only up to it

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Re: Noddys Natterings , Vuskys rolling road results

Post by M'coli » Tue Sep 13, 2011 4:38 pm

That sounds alright, does that - good stuff. What SU needles are you using?
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Re: Noddys Natterings , Vuskys rolling road results

Post by Lotus-e-Clan » Tue Sep 13, 2011 4:44 pm

Dave

First of all the main interest relates to torque and AFR ...the power runs are very similar because that's the consistency of the physics of the engine as an "air pump".

The two runs mirror the AFR trace and its the torque thats mainly affected by the drop in AFRs on the second run ...best guess will be rising air temp (= less air) at the air filters /in hotter induction tracts as the cause of drop in AFR and torque. .

Reading the AFR curves from left to right it looks like the throttle was blatted wide open at about 2000 rpm. So I guess that's when the AFRs dive to 9.6 as the piston is held down by the piston damper oil (that is if SUs are the same as Stroms in that respect -never had SUs so you tell me).

As the revs rise the AFR rise too as proportionally more air is mixed to the fuel as the piston damper is overcome.

What damper oil do you use? ...asking because a obviously a thinner oil might prevent the AFR going so low.

Assuming the RR AFRs compare to my system, then 9.6 AFR = bogging down in my experience. you can see the torque curve improve with the rising AFR and then deteriorate again as the AFR dips at the mid point.

What the dip is I don't really know but I guess it's a physical phenomenon related either to breathing, fueling or ignition eg:
  • beathing: a dip and revcovery in exhaust scavenging / breathing associated with cam / ports/ exhaust system design which you can't do much about by tweakingt carbs ....or

    fueling (1): the SU needle profile is providing more fuel at that point (? a shoulder on the needle part he way along?) or

    fueling (2): the SU piston, or piston damper is sticking momentarily somehow
    (Because you've got twin SUs it could just be one SU playing up in that respect )

    ignition (1): advance beyond 3600 rpm is wrong

    ignition (2): centrifugal plate sticking (less likely I'd guess)
Max torque is produced on an AFR of 12.5 @ 4500rpm (12.5 is a guess based on the 9.6 min and 13.3 max as the AFR scale numbers are is missing!)
But you can't assume because the torque curve then drops off as the AFR rises that less torque would be produced if the AFR was 13.3 at 4500 because the physics of the engine tune could be playing a part....which is clearly the case because the second run has lower AFRs and but the same shaped torque and AFR curves!

Anyway enough food for thought for now but I'd still be aiming for higher AFRs (12.8 - 13.2) at the lower revs to gain more torque and even better drive-ability. So less fuel or more air is needled lower down; eg less fuel = a slightly fatter needle lower down and /or the piston damper is a bit too damper-ish :lol: :wink:

EDIT: But having said all that :roll: I'd be VERY keen to optimise the ignition curve first 'cos THAT alone could produce the overall low AFRS when you boot it (so mechanical advance only - no vacuum obviously) and the shape changes in the torque and AFR curves ...
Last edited by Lotus-e-Clan on Tue Sep 13, 2011 4:53 pm, edited 2 times in total.
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Re: Noddys Natterings , Vuskys rolling road results

Post by Meltdown » Tue Sep 13, 2011 4:49 pm

Good to see that your tinkering has paid off, you must be a happy chappy :D Did they tweak anything for you?
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Dave ' Linwood ' Lane
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Re: Noddys Natterings , Vuskys rolling road results

Post by Dave ' Linwood ' Lane » Tue Sep 13, 2011 5:08 pm

Thanks for the info Pete . To answer some of your questions .
Damper oil is SUs own so quite thin
There is no flat spot / hesitation / bogging down I can feel when pulling away , it still needs a tiny bit of choke to start cold , Does start instantly when hot and ticks over even , I do think its a tad rich though as you say as it can be a bit smelly ticking over .
Dip confused him , needle profile has a very slight dip that corresponds with the big dip on the graph , il check the needle profile but its a tiny variation so this could be it
Piston is smooth and free.
On my CO meter the % rises a fair bit when you blip the throttle , then drops off
Dizzy is a NOS 41422 standard 25d4 , theres no dwell variation and the mark on the pulley is 100% stable on tickover and higher revs , vacuum advance is fine as is the centrifugal backplate , perhaps the curve is wrong , its got a sport cam but ive no sport dizzy to match it .
I know it could be better but just how to do this without spending money ive not got is a mystery :)
Im Fairly sure its not going to melt valves or blow up which is a good thing , unless you think it might Pete :?: :?: :roll:
Just how far do you go with a boggo L4 :?: :lol:
Last edited by Dave ' Linwood ' Lane on Tue Sep 13, 2011 5:36 pm, edited 1 time in total.
Formally known as " Noddy "
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Dave ' Linwood ' Lane
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Re: Noddys Natterings , Vuskys rolling road results

Post by Dave ' Linwood ' Lane » Tue Sep 13, 2011 5:12 pm

Lotus-e-Clan wrote:
[
EDIT: But having said all that :roll: I'd be VERY keen to optimise the ignition curve first 'cos THAT alone could produce the overall low AFRS when you boot it (so mechanical advance only - no vacuum obviously) and the shape changes in the torque and AFR curves ...
Just how do I do this :roll: :? :)
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bazzateer
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Re: Noddys Natterings , Vuskys rolling road results

Post by bazzateer » Tue Sep 13, 2011 5:17 pm

M'coli wrote:What SU needles are you using?
If I told you I was a pathological liar, would you believe me?
Barry Blackmore - Chiltern ACO, apparently.......................
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Dave ' Linwood ' Lane
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Re: Noddys Natterings , Vuskys rolling road results

Post by Dave ' Linwood ' Lane » Tue Sep 13, 2011 5:23 pm

M'coli wrote:That sounds alright, does that - good stuff. What SU needles are you using?
Needles are 0.090 fixed jet lettered JM .
BUT this relates to my engine and my air filters and the associated wear in a tired L4 so might not be correct for yours , might not be correct for mine come to think of it :lol:
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Lotus-e-Clan
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Re: Noddys Natterings , Vuskys rolling road results

Post by Lotus-e-Clan » Tue Sep 13, 2011 5:41 pm

Noddy wrote:
Lotus-e-Clan wrote:
[
EDIT: But having said all that :roll: I'd be VERY keen to optimise the ignition curve first 'cos THAT alone could produce the overall low AFRS when you boot it (so mechanical advance only - no vacuum obviously) and the shape changes in the torque and AFR curves ...
Just how do I do this :roll: :? :)
Well the first thing to do is to plot the actual curve as it is now with absolutely no changes following the dyno test.

Firstly note Static = and the number of distributor degrees actually stamped on the centrifugal advance stop inside the dizzy/
then disconnect the vacuum and note the MECHANICAL advance in CRANK degrees with a strobe for:
  • 1000 rpm (or whatever tickover you use)
    1500
    2000
    2500
    3000
    3500
    4000
    4500
    5000
    5500

    6000 ...or upto the point where the advance simply stops note the exact revs when the advance stops
The most interesting point on the curve at the moment will be 3500 - 5500 where the torque and AFR curves dip then recovers and then dips again.

Once you've got that data post it up possibly with a picture of the springs inside the dizzy (just for info). This is mainly of academic interest /education because the solution will most likely be conversion of your dizzy to a Sport Spec advance curve (no brainer really :lol: )

Now then, it's possible to change the springs at low cost to convert the dizzy to a sport spec assuming the centrifugal advance stop is on the money for a Sport spec (but that can be tweaked too).
The distributor Doctor on line has a comprehensive list of Lucas dizzy specs. So the starting point is to email him the correct dizzy number for a Sport spec 25D4 and he'll send you the correct primary and secondary springs for a few quid.
74 Clan Crusader 1040 Red 190 bhp/ton
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