James7

Many thanks for organising this Gavin. I've been in touch with Andy and my exhaust will soon be sorted James

I have one - YHBM

The catalyst in the silencer of my Powerspeed exhaust needs replacing. Not sure if this qualifies for the ‘bulk buy’ but would be grateful if you could ask when you speak to them. Thanks James

YHBM

Stuart, YHBM

Ok, will order a couple of those then thanks.

Thanks all. If it would put me into class 2 I’ll postpone this upgrade and look to come and have a go in Class 1 first, thanks David. Look forward to hearing your thoughts once built though Boss Hogg!

I’ve removed the original non adjustable one by unbolting the clamps and pulling out the ball joints. The standard one has clamps like these with rubber bushes inside. I don’t think these will transfer onto the adjustable ARB and certainly won’t slide over the ‘blade’ side. Should I be using some type of 2 part clamp and bush that will split in half / where can I get the necessary items from? What sort of grease should I use on the ball joints on re-assembly – would one of these be suitable? Thanks James

The new Supersport with its 5 speed ‘sprint ratio’ gearbox seems to be getting some very good press at the moment. Does anyone know what ratio changes have been made in the gearbox and which diff ratio is fitted (still 3.92)? I’d guess a higher first and second, possibly a lower 5th. I’d be interested to know exactly what though as I’m thinking of having my 5 speed ‘box modified to better partner my standard 1.6 K Series. As well as the short first gear, I find the gap between second and third too big and particularly noticeable on some track days. Third and fourth seem ok. 5th is good on the motorway / touring but may be better lowered slightly for track use. The BGH‘2.8 Sporting Close’ looks to be an improvement over standard. With their ratio options of 2.66, 1.75, 1.26, 1.0 and 0.86 and the 3.92 diff, GearCalc gives the following: Gear Mph per 1000 RPM Mph @7000 RPM ---------------------------------------- 1 6.20 43 2 9.43 66 3 13.09 92 4 16.50 115 5 19.18 134 Mph RPM (in Gears) ------------------------------------------------- 1 2 3 4 5 ------------------------------------------------- 5 806 530 382 303 261 10 1612 1061 764 606 521 15 2418 1591 1146 909 782 20 3224 2121 1527 1212 1042 25 4031 2652 1909 1515 1303 30 4837 3182 2291 1818 1564 35 5643 3712 2673 2121 1824 40 6449 4243 3055 2424 2085 45 4773 3437 2727 2346 50 5303 3818 3030 2606 55 5834 4200 3334 2867 60 6364 4582 3637 3127 65 6894 4964 3940 3388 70 5346 4243 3649 75 5728 4546 3909 80 6109 4849 4170 85 6491 5152 4431 90 6873 5455 4691 95 5758 4952 100 6061 5212 105 6364 5473 110 6667 5734 115 6970 5994 120 6255 125 6516 130 6776 Gear Change RPM drop (change @7000) --------------------------------------- 1 -> 2 -2395 (to 4605) 2 -> 3 -1960 (to 5040) 3 -> 4 -1444 (to 5556) 4 -> 5 -980 (to 6020) Some of the Ratios listed by Trans-X look interesting too. If I took their higher first and second ratios (2.48 and 1.69) kept 3rd and fourth as standard and the lower 0.86 5th gear, (as BGH option) the gaps between 1-2 and 2-3 would be reduced even further. First is still no higher than first in the Caterham 6 speed when fitted with the 3.62 diff (10mph is 1503rpm vs 1506rpm). GearCalc results as below. Gear Mph per 1000 RPM Mph @7000 RPM ---------------------------------------- 1 6.65 47 2 9.76 68 3 13.09 92 4 16.50 115 5 19.18 134 Mph RPM (in Gears) ------------------------------------------------- 1 2 3 4 5 ------------------------------------------------- 5 752 512 382 303 261 10 1503 1024 764 606 521 15 2255 1536 1146 909 782 20 3006 2049 1527 1212 1042 25 3758 2561 1909 1515 1303 30 4509 3073 2291 1818 1564 35 5261 3585 2673 2121 1824 40 6012 4097 3055 2424 2085 45 6764 4609 3437 2727 2346 50 5122 3818 3030 2606 55 5634 4200 3334 2867 60 6146 4582 3637 3127 65 6658 4964 3940 3388 70 5346 4243 3649 75 5728 4546 3909 80 6109 4849 4170 85 6491 5152 4431 90 6873 5455 4691 95 5758 4952 100 6061 5212 105 6364 5473 110 6667 5734 115 6970 5994 120 6255 125 6516 130 6776 Gear Change RPM drop (change @7000) --------------------------------------- 1 -> 2 -2230 (to 4770) 2 -> 3 -1781 (to 5219) 3 -> 4 -1444 (to 5556) 4 -> 5 -980 (to 6020) I’d hope that having BGH or similar changing 3 gear ratios should give a good close ratio gearbox with a higher 5th gear than top in the 6 speed but at significantly reduced cost compared to buying a used 6 speed, having it serviced / rebuilt if necessary and having the diff rebuilt to 3.62 ratio. Any thoughts? As an aside, do any of the sprint and hillclimb guys know whether this would cause any problems with eligibility for Class 1, should I look to compete in the clubs speed events? And finally... while not looking to make this an excessively long post(!), for comparison the standard 5 speed and 6 speed results are shown below, all calculated with 185/60 R13 tyres Cheers James Standard 5 speed with 3.92 diff: Gear Mph per 1000 RPM Mph @7000 RPM ---------------------------------------- 1 4.91 34 2 9.12 64 3 13.09 92 4 16.50 115 5 20.00 140 Mph RPM (in Gears) ------------------------------------------------- 1 2 3 4 5 ------------------------------------------------- 5 1018 549 382 303 250 10 2036 1097 764 606 500 15 3055 1646 1146 909 750 20 4073 2194 1527 1212 1000 25 5091 2743 1909 1515 1250 30 6109 3291 2291 1818 1500 35 3840 2673 2121 1750 40 4388 3055 2424 2000 45 4937 3437 2727 2250 50 5485 3818 3030 2500 55 6034 4200 3334 2750 60 6582 4582 3637 3000 65 4964 3940 3250 70 5346 4243 3500 75 5728 4546 3750 80 6109 4849 4000 85 6491 5152 4250 90 6873 5455 4500 95 5758 4750 100 6061 5000 105 6364 5250 110 6667 5500 115 6970 5750 120 6000 125 6250 130 6500 135 6750 Gear Change RPM drop (change @7000) --------------------------------------- 1 -> 2 -3229 (to 3771) 2 -> 3 -2127 (to 4873) 3 -> 4 -1444 (to 5556) 4 -> 5 -1225 (to 5775) Standard Caterham 6 speed with 3.62 diff: Gear Mph per 1000 RPM Mph @7000 RPM ---------------------------------------- 1 6.64 46 2 8.89 62 3 11.24 79 4 13.54 95 5 15.81 111 6 17.87 125 Mph RPM (in Gears) ---------------------------------------------------------- 1 2 3 4 5 6 ---------------------------------------------------------- 5 753 563 445 369 316 280 10 1506 1125 890 739 632 560 15 2258 1688 1335 1108 949 840 20 3011 2250 1780 1478 1265 1119 25 3764 2813 2225 1847 1581 1399 30 4517 3375 2670 2216 1897 1679 35 5270 3938 3115 2586 2214 1959 40 6022 4500 3560 2955 2530 2239 45 6775 5063 4005 3325 2846 2519 50 5625 4450 3694 3162 2799 55 6188 4895 4063 3479 3078 60 6750 5340 4433 3795 3358 65 5785 4802 4111 3638 70 6230 5172 4427 3918 75 6675 5541 4744 4198 80 5911 5060 4478 85 6280 5376 4758 90 6649 5692 5037 95 6008 5317 100 6325 5597 105 6641 5877 110 6957 6157 115 6437 120 6717 125 6996 Gear Change RPM drop (change @7000) --------------------------------------- 1 -> 2 -1770 (to 5230) 2 -> 3 -1463 (to 5537) 3 -> 4 -1189 (to 5811) 4 -> 5 -1008 (to 5992) 5 -> 6 -805 (to 6195) Edited by - James7 on 30 Dec 2011 22:17:53

Link

YHBM James

Hi Guy, Dibs on S3 blade adjustable front antiroll bar please – YHBM Thanks James

Interesting idea. Hope you don’t mind me asking a few associated questions that may well be relevant to your build. Am I right in thinking that VVC engines have a hydraulic clutch rather than a cable operated one? Why is this / could it be done by cable? Is there any difference between the VVC engine fitted by the factory in a Roadsport and in the later R300 (after they stopped fitting the roller barrels)? What diff ratio did K series R300s and 6 speed VVC Roadsports come fitted with? Slightly o/t but what are the differences between the VVC Roadsport and R300? I guess that the Roadsport may have had some items as options (6 speed, wide track, big brakes) but apart from carbon front wings, is this car the same spec as a VVC R300?

Ok thanks Chris. My garage is very small though so I think it will be too long! James

Does this have the folding tow pole option? Thanks James

Nick, YHBM Thanks James

Thanks for the replies all. Bri, I have family in Skipton (and Halifax) and pass near to Silsden not infrequently so we may be able to arrange something convenient. I’ll BM you my details, thanks. Mankee, thanks for your swap offer, if I decide to give the standard springs a go I’ll be in touch. What springs are you currently running on your car? How do you find them? Any idea of the history and condition of your standard springs? Mine are in good condition, minimal marking / stone chippng and I believe have only been used for road and track days for the last few years, never actually raced. I don’t have anything else to compare against on track but to me the springs feel good. The car feels stable with very little roll. If I only used my car on track I’d keep them as they are, it’s only on road that I find them a problem. James

Something like this shouldn't be too tall.

That would be very kind thanks Bri. I’m in Leeds, how about you? James

I've had my 1.6K 7 for about 10 months and find the suspension is a bit firm on bumpy roads. You certainly notice imperfections in the road and on very bumpy roads it really bounces up and down. Only mildly bumpy sections of road can have the rear wheels lifting and the wheels spinning up. Sometimes I end up having to back off and go a fair bit slower than otherwise might in a regular car. The car is a 2004 Ex Academy with narrow track front suspension and came with the standard Bilstein M0 dampers with adjustable platforms. The springs had however been changed to the Caterham Race Eibach items. I believe that these are 250lbs/in front and 215 lbs/in rear, whereas the standard items are 150 lbs/in front with progressive rear springs (from 0 - 95 mm: 110lbs/in, the next 87.5 mm: 130 lbs/in and the remainder: 200 lbs/in). The car has a front ARB with red bushes. There is a rear ARB which is using the rearmost mountings. I use the car mainly on the road but have done a couple of trackdays and anticipate that I’ll continue to do a few trackdays a year and might look to try my hand at sprinting/hillclimbing at some point in the future. I understand that these springs may be under damped with the standard Bilsteins. I don’t want to change the dampers, though and I suspect the springs may be too firm for the road in any case. I’m considering the following options (in no particular order) and would appreciate any comments/further suggestions on what might achieve a good ride/handling compromise on both road and track. 1. Fit standard Caterham springs front and rear (rears progressive); 2. Keep the Race fronts and fit standard progressive rears; 3. Keep the Race fronts and fit Caterham 21 progressive rear springs(Part 24076 - 30% stiffer than standard progressives); 4. Fit 170lbs/in fronts (Part 75517) and Caterham 21 progressive rear springs. Many thanks. James

Many thanks to all for your information and advice. Do you know where the Intro to Sprinting day will be held Simon? I’m sure that I’ll be very tempted by that! Richard, I’m very interested to hear your opinion on the race springs (in many ways glad). They were fitted when I bought the car and I do find them too stiff on the road, both bouncing the car around and losing traction on even mildly bumpy roads. In these conditions I’m sure softer springs would be better. I believe that the race springs are 250lbs/in front and 215 lbs/in rear, compared to 150 lbs/in front and progressive rear for the standard setup. I’ve been planning to ask the question in Techtalk (and might yet do so) but hadn’t really thought about implications for sprint class. Having done some reading up in the archives, the options I've been considering are: 1. Standard springs front and rear; 2. Keep the Race fronts and fit standard progressive rears; 3. Keep the Race fronts and fit Caterham 21 progressive rear springs(Part 24076 - 30% stiffer than standard progressives) 4. Fit 170lbs/in fronts (Part 75517) and fit Caterham 21 progressive rear springs. Any thoughts on how these options would affect the class and the general ride / handling compromise on both road and track? The Throttle body could be swapped back in no time and some list 1a tyres shouldn’t be too expensive. The exhaust a little more tricky and there looks to be some debate on legality for class1 so I guess a definitive answer on this would be ideal. To be honest I’d be surprised if even both throttle body and exhaust combined would push it over 125bhp although I could be wrong. Aren’t they meant to be 115-120bhp as standard? I take the point about coming along and having a go first and foremost though and will aim to do this but would like to do something about the springs in any case. Cheers James

Having owned my 7 for nearly a year and done a couple of track days with her, I may have a go at sprint / hillclimbing at some point, probably not next year, but possibly the one following. I’ve had a Look at the 2011 Lotus 7 Club Speed Championship Regulations and am trying to work out what class I’d fall into and what affect any current (mainly reversible if necessary) or possible future mods may have on the class the car would be eligible for. I'd be grateful for any advice. I don’t necessarily think I’d be fighting it out for the lead in a class, but guess it might be better to compete in a class on a relatively level playing field rather than to have a minor modification move you up against more powerful machinery! My car is a 2004 1.6K ex-Academy. With the only current mods being a Powerspeed 4-2-1 exhaust, 52mm throttle body and Yokohama A048 tyres and Caterham race springs with the standard Bilstein adjustable platforms. Reference is made in the Regulations to ‘Caterham Sevens which fully comply with the current technical specification for the ‘2011 Caterham Graduates Championship’ – ‘Caterham Mega-Graduates Class’ specification cars only. Cars must fully meet the specification relevant for engine type and year of construction. No further modifications are permitted.’ Would this affect me? Where might I find details of the regs for a K series car such as mine if so? Many thanks James Edited by - James7 on 31 Aug 2011 23:48:39

Possibly this, part number 79502 which is listed as the throttle cable for X/Flow & Vauxhall 8v ?

Glorious sunny weather in Leeds today

YHBM Re the head restraint & steady bracket. Is this suitable for an FIA single diagonal roll bar (not full cage)? Thanks James