Tony C

In agreement with yankeedoodoo. Drag can become a horribly complex subject if you allow it Wind tunnel testing allows quantification and then mathematicians try to rationalise the results. When driving down the road you are basically making a 7 shaped hole in the air. CD is the drag coefficient and is a value which represents the ratio of the pressure differential between the higher pressure at the front and the lower pressure at the back, divided by the air density multiplied by the speed of the car squared (density can be ignored because altitude is not changing significantly). If you maintain the same proportions, making the shape smaller will not affect CD; so frontal area (S) must also be considered. Have to go to work now - maybe more later 😬

Me please, carbon. 😬 Thanks Waiting for my BRG SV kit. 😬 DELIVERY BROUGHT FORWARD, only three weeks to go now - WHOOPEE

Just received my remote sensor set-up from"Think" today - 27 quid, inc VAT & postage. Factory swaged stainless braided 14 inch line, adaptor for oil filter 'end', 'T' piece adaptor, 'T' piece - with adaptor for mechanical gauge capilary tube and pressure switch. If anyone needs Part Numbers, drop me an e-mail. Don't know how this price compares to the Caterham one.

Not giving anybody in particular a hard time you understand, but I am simple amazed at some peoples thinking process Why worry about whether something is 'legally' required or not. The petty strut gives the roll bar added resistance to bending. It also adds rigidity to the space frame. No brainer really - pun intended STILL waiting for my BRG SV kit. 😬 ONLY five weeks to go now - nearly there

Sounds interesting Chris I was thinking of making my own sequential change light 'thingy' and found the 'gizmo' at Maplin, but chickened out when it became obvious that I would need to know what I was doing - my "Bigger 'ammer" approach doesn't work with 'wiggly amps'. I was looking into the possibility of either fitting the lights into the pad on the steering wheel or maybe mounting them on top of the scuttle to reflect off the inside of the windscreen a-la HUD 😬 If you could make a sequential change light set-up, I'd be more than interested in buying one. 100 squid for the Omex sequential must be daylight robbery when you consider the bits and pieces are so cheep to buy. Cheers, Tony STILL waiting for my BRG SV kit. 😬 ONLY five weeks to go now - nearly there

Tonks Richard 😬

I seem to remember seeing a post recently, maybe in the archive, which stated the thread size on the electric oil pressure transmitter of a 'new' K series engine was M12 x 1.5, but now can't find it. Can anybody please confirm 😬 I also assume this is not a tapered thread. Thanks in advance, Tony

Stuart, IMHO your doing the right thing to get the experts to check it out if you're not comfortable with poking around with it yourself - brave man Ziiiing - what was that, nearly went in my eye 😬 Give Caterham a call if you're local, good idea and lucky you 😬 You still haven't given us a better description of the noise than whirring - perhaps a rising banshee wail, afraid the thing is going to jump out of the car? Cheers, Tony Edited by - Tony C on 24 Feb 2003 22:10:03

Stuart, I'm being serious now From your description it sounds like the starter motor is not engaging the ring gear on the flywheel and may not be a purely electrical problem. Is it a whirring sound or more like a rising scream? I'm not certain about the modern mechanism used to engage the starter, but it used to engage upon starter motor rotation. I suggest you wait a bit for more detailed advice, but failing that you'd be better-off getting it checked by a reputable garage with the proper test equipment. Good luck and tell us more about the noise. Cheers, Tony

Humour - what's that then? 😬 Give it a whack with an 'ammer - that'll fix it 😬 STILL waiting for my BRG SV kit. 😬

Peter, I was assisting in the engine insertion in question and there is no removable rail. or We checked the mounting brackets against another 7 and they were slightly different, but it had a plastic plenum and there was 'shed-loads' of clearance between the rail and the plenum. Colin's car is brand new, the engine is 1800 cc and has the aluminum plenum fitted. I guess Caterham are aware of the tight clearance because the rear two plenum branches have a small amount of material removed at the bottom - I guess to give a small clearance with the chassis rail. When we correctly positioned the engine it was impossible to lower the engine fully onto the rubber mountings - the rear two plenum branches were resting on the chassis rail. We fitted five washers TEMPORARILY so that we could disconnect the crane and push the car back in the garage. The washers between the rubber mounting and the bracket give a couple of mm clearance at the plenum/chassis rail, but bring the top of the plenum 'a bit close' to the underside of the 'lid' - so this could not be a permenant 'fix'. I guess the guy grinding off the plenum branches stopped too soon - IMHO that is the problem. If on Monday Caterham say "That's alright, they're all like that". They'll be reciving a terse response 🙆🏻 It wouldn't be a good idea for 'us' to grind away until there is sufficient clearance - I can just immagine Caterham's "Why did you do that?" We checked the engine on the other 7 and it doesn't seem to move much on its mountings when rev'd, but IMHO, the vibration would quickly do a 'power of no good' to the plenum. It would be nice to hear from any other recent new engine 'inserters' to find-out if this problem has been encountered before, and what was Caterhams "Answer". Cheers, Tony Edited by - Tony C on 22 Feb 2003 20:52:56

WOW Thanks for that Chris - just about answers my question 😬 Cheers Tony

No I don't fancy the sticky mess of waxoil either. I know waxoil is "easy" to apply, but I think it's intended for 'inside' areas, not subject to direct blasts of salt, water, carp etc. I'd willingly sacrifice the weight incease for the added corrosion protection. Lots of people think Aluminium alloy panels don't corrode! The mix of metals in the 7 chassis, plus moisture is a 'nice' cocktail. A cheap ticket for the metal to return to the holes in the ground from which they came. I fancy something which is easy to apply; brush on, and will give a non sticky surface and remain flexible.

Well I thought it amusing 😬 Anyone know what the aluminium in wheels is alloyed with? Copper, zinc? Just curious

Nice to meet you last night Chris and look forward to seeing your new SV on Saturday. I wish I'd met you earlier, I could have avoided all those lectures and the 17 years I spent as an Aircraft Engineer learning the practical aspects of, among other things, Lead-Acid battery care and maintenance. I'm now going to have to write to all my past instructors to inform them that they were wrong when they told me that for practical purposes off-load voltage is of little value. Those wasted weeks in the battery shop when I was an apprentice! When I inform my colleagues at work that they've been misinformed all these years and they've been telling their students this foolishness there will be manifold gnashing of teeth and rending of garments. I hate to contemplate the reaction when I tell the guys in the hangar. Oh my God, just think of it! Must also write and tell they guys at the CAA, FAA and JAA. Oh no - the paperwork. The above is hardly worthy of this discussion, but I'm sorry, I just couldn't resist. 😬 Cheers, Tony STILL waiting for my BRG SV kit. 😬

WHEN my kit finally arrives I was considering suspending the front end from the engine crane and inverting the complete body by me lifting and twisting from the rear. Resting it on suitably padded axle stands and giving the entire underside a good undersealing/waxoiling in all its little nooks and crannies. Anybody else tried this? STILL waiting for my BRG SV kit. 😬

Not a total loss then I'll try it out on Colin's brakes on Sat and see how it goes 😬. Thanks for the feedback. Cheers, Tony

Guys, just got a "Mityvac Brake Bleeding Kit". Has anyone any experience with this seemingly good bit of kit? Apparently it's attached to the bleed nipple and a vacuum (well suction I guess) pumped to draw fluid through from the reservoir. My thinking is: if a 'vacuum is drawn the fluid will displace the entire volume of the brake system and air bubbles won't be 'left behind'. Sounds good in theory; guess I should have asked before buying I suppose, but I'll be trying it out on Colin Grundy's car first 😬 STILL waiting for my BRG SV kit. 😬

Sorry V5000SV, got a bit carried away there 😬 Redtop apparaently do a fine line of 'Racing' Batteries which will give you more crank-ability. As to the other matter; just consider an average 'Joe Bloggs' intending to start his car and only getting "CLICK". Testing the battery (after kicking the obligatory cat of course 😬 ) using your proposed off-load voltage method Chris and getting a 12.6 volt reading or more, which according to you indicates 100% charge, will mislead poor ol' Joe into thinking that his battery is not the problem 😬 Does this sound like a good idea to promulgate ? The object, IMHO, of testing a battery is to discover if it is the problem. Off-load voltage is worthless for this purpose, or for anything other than testing your multimeter 😬 This is not my opinion, it's fact. Readers of this forum, when it comes to technical subjects like this, are not interested in your opinion, OR MINE, but cold, hard facts that they can use to trouble-shoot their problem. It is a WIDELY accepted fact that on-load voltage and electrolyte SG together, are a reliable indication of the state of your battery. If you switch on your headlights for a few minutes and still get 12 volts and the SG of each cell is "in the green", you can be reasonably certain that the fault lies elsewhere in the system. STILL waiting for my BRG SV kit. 😬

No problem Chris. BUT, I don't think "what works for you" has any real value in what we are trying to achieve here. I'm not disagreeing with you, I am merely trying to diseminate widely accepted facts; trying to pass on information to others, so that they have a different understanding, hopefully of value to them in the care and understanding of "that lump" in the corner of their engine bay. There is zero "my opinion" in the facts I have presented here and above. 😬 I know you were joking, but I don't intend to fight; nothing to fight about ! Please read the bit I have just added to the previous post. Don't particularly like the lock and sluice gate analogy either 😬 You can't argue with chemistry !!! OFF LOAD VOLTAGE IS WORTHLESS as a practical indication of the work that can be got out of "That lump in the corner" with Banner written on it; not an opinion - fact. 😬 Cheers, Tony

Hi Chris, how you keeping. We do both seem to enjoy battery threads 😬 I can only bang my head on the nearby wall and direct attention to my previous entry. OFF-LOAD VOLTAGE IS WORTHLESS. A discharged battery, for the purpose of doing useful work (why else do you have a battery), after a 'rest' will still give 2.2 volts per cell, but will not even be able to 'pull-in' the starter solenoid. So what is the value of a seemingly 'good' 'off-load' voltage? - zero, nada, zilch, nil, none It's dead, gone, deceased, knackered, boat anchor - until recharged, of course. With the greatest repect; what is the point of researching the subject, presenting the FACTS and people not even bothering to read them? I give-up! 😬 A lead-acid battery stores chemical energy - not electricity !!!!!!!!! Once the chemical energy is used, beyond a certain value, that's IT - you then need to restore the chemical energy by recharging. As Peter said, the alternator or external charger has to supply about 14 volts, otherwise NOTHING will "go in" !!!!!!!!!! To ascertain the chemical energy in a lead-acid battery the SG of the electrolyte must be measured - and even that is not infallable! But SG and on-load voltage together are pretty reliable. What on-load? Don't know specifically, but headlights would be IMHO a reasonable load. This will floor you - electrons flow out of the negative battery terminal, into the chassis and back, via the closed circuit wiring, to the battery positive terminal !!!!!!! 😬 I am really banging my poor computer keys in frustration 😬 Please find the time to read and absorb the '7faq extract' I posted earlier - Please. One of the resons for my suggestion for a "Good Engineering Practice" 'thread' was so that we can all get away from the personal opinion side of some of the more technical subjects. The three-above entry: "Extract from 7faq" is a cut-and-paste from the article on lead-acid batteries. OK, I wrote the article, but it was not a quick ten minute 'job', replying to a previous entry "off the top of my head". I used several respected publications for the facts and the article has been verified independently by several experts in the field - just so we don't continue to misunderstand one another. I am not putting myself forward as the final arbiter on this, or any other subject. I guess I should have waited until 7faq goes 'public', but off-load voltage is worthless for our purposes and it needed saying - sorry! Might be a worthwhile article for LF - in its entirety. STILL waiting for my BRG SV kit. 😬 Edited by - Tony C on 17 Feb 2003 23:06:01

Extract from the 7faq Battery thing. The 'off-load' voltage of a lead-acid cell, that is, its voltage when no electrical devices are connected, just a voltmeter, is approximately 2.2 volts. The 'off-load' voltage is the same for every lead-acid cell regardless of its plate size and remains at this value until the cell is practically 'dead', regardless of its state of discharge. When the cell approaches total discharge, its 'off-load' voltage begins to drop rapidly. This is the reason that the 'off-load' voltage of a battery is NOT a reliable indication of its state of charge. The 'on-load' voltage of a cell, that is, its voltage when electrical devices are being supplied by the battery, decreases gradually as the cell is discharged. This gradual decrease in terminal voltage is due to a gradual increase in the internal resistance of the cell caused by sulphation of the plates. This is the reason that the 'on-load' voltage of a battery IS one of the reliable indication of its state of charge. To give a high discharge current and a high terminal voltage under load, a battery must have low internal resistance. This characteristic can be achieved through extensive plate area. therefore, each cell contains several sets of plates. All the positive plates of a cell are connected by one connecting bar, and all the negative plates by another. Thus the plates are connected in parallel, further decreasing the internal resistance of the cell. The 'off-load' cell voltage is not affected; it remains the same as that of a single pair of plates. There being six cells, the 'off-load' voltage of a '12 volt' battery should be between 12.6 and 13.2 volts. A battery loses water by evaporation and by 'gassing' at the plates when fully charged. The level of the electrolyte should be maintained at all times approximately 1/4 inch above the top of the plates by topping up with distilled water or de-ionised water. NEVER EVER TAP WATER. The state of charge of a lead-acid cell can be most reliably determined by measuring the strength of the electrolyte solution. This is done with a HYDROMETER which measures the specific gravity(SG). A fully charged cell will have an SG of about 1.27 and a discharged cell will have an SG of about 1.17 When the battery is connected to an external circuit and current is flowing, lead sulphate is formed at both plates and the specific gravity will fall as the acid becomes weaker. When the SG has fallen to 1.17 the battery should be recharged. (The actual SG is dependent upon the temperature of the electrolyte. A hydrometer is not easy to read accurately and usually has coloured bands to make it easier to determine the state of charge). To charge a battery it is connected to a battery charger (an external charger or the car's alternator). which applies a slightly higher voltage (about 14 volts) and causes current to flow in the 'reverse' direction. While this is happening the lead sulphate which had been deposited on the plates is removed and the SG of the electrolyte rises to 1.27. As stated previously, the 'on-load' voltage of each cell of a fully charged lead-acid battery should be 2 Volts. The 'off-load' voltage of each cell of a lead acid battery should be 2.2 Volts. NOTE: The 'off-load' voltage IS NOT a reliable indication of the state of charge, whereas the 'on-load' voltage and/or the SG of each cell IS a reliable indication. Also be aware that each cell must have the required SG. One cell showing a lower SG than the others is an indication of a ‘dead' battery. 😬 😬 STILL waiting for my BRG SV kit. 😬

Battery voltage 'off-load' is of limited value - well, OK, it's of no value whatsoever. 'Off-load' should be 2.2v per cell, but this is meaningless because a nearly fully charged battery will give this value 'On-load' is better. 'On load' should be 2v per cell. with a fully charged battery. Testing the SG of the electroyte with a hydrometer will give a meaningful state of charge for each cell. Usually it is one cell which is 'asleep' if the battery is not doing a proper job. Cheers, Tony STILL waiting for my BRG SV kit. 😬

(Oar In) Also one has to consider the relationship between what is not illegal and what is smart 😬 I'd hate to hear this phone conversation: "Hello Caterham, this is Rover. I hear some of the Caterham owners have got hold of the unlock code." "Wasn't us that supplied it." Replies Caterham. "Tough luck, we have been slapped with a multi million pound law suit for exceeding emission standards, you can't buy your engines from us any more." (Oar Out)

Cough 😬 Still waiting for my BRG SV kit. 😬