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Leno

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About Leno

  • Birthday 01/30/1955

Profile Information

  • Location
    Cornwall
  • Cars Owned:
    TR4, with Alfa 159 Daily transport
    To rebuild one day: -TR4, TR3A, TVR2500, Alfa2000GT Veloce

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  1. Good to see those photos again Julian - Thanks, If I remember correct, I think Rodney just beat me to the line - close competetion for a 150hp TR6 against a 4 cylinder! After Ryan had the car, I think 883 GOH was bought by a Yorkshire firm that had 3 or 4 cars that they rallyed, they did have a youtube clip of 883GOH on a rolling road being tested and tuned, but couldn't find it today when I searched - probably it's now too old - or else it's been deleted Len
  2. Hi Pete I bought 883GOH from Gerald in 1998 with another donor TR4 car 358EXV. The cars were taken to west Cornwall so not sure where the 'last known to have gone to Scotland' came from. A bit of the history I remember is that Gerald rallyed the car in the early 60s' and was a member of the London Motor club; I can remember that as I had to take the club badge off of the car grill and give to Gerald to keep. The car was taken off the road in 1968 when Gerald was assigned to America with EMI if I remember right. At one stage, the car was stored in Kent, where a tree fell on the barn and a beam then landed on the roof of the car (see photo). When back in England Gerald purchased a second TR4 in the 80's as a donor car to rebuild 883GOH, but never got around to it with running his business in Exeter. He advertised the two cars in 1998 and I purchased them both. I rebuilt 883GOH over the next 2 to 3 years, and uprated the car to do historic road rallying - which I had got the bug for after navigating on Le Jog in 1997. I even sold my TR5 to fund the project. All the original panels were kept and I only purchased two new sills, the base of the wings had new metal shaped and welded in, even the ally hardtop was beaten out, and the surry frame straightened. The second photo is of the car in 2001 fresh after the rebuild. The car was rallyed by myself with three diifferent navigators over the next 4 years, and we won three events in it, two HRCR clubmans championship events and the 3 day Circuit of Wales in 2003. Due to a sudden illness and going down with ME/CFS in December 2005, I was unable to drive for a while and actually thought I'd never be able to drive 'in anger' again so sold the car to Roger Bricknell in 2007. Roger then successfully rallyed the car and won another three events with it I believe, before selling it to Ryan Pickering (who was one of my navigators). Ryan won a couple events with it as well, proving the car was very competitive in any drivers hands. 883GOH is probably the best TR I've ever owned (out of the 8....so far), so much so that the donor car that came with 883GOH is now in the process of being rebuilt as a copy! I've been working on 358EXV for several years now, but seem to have less time every year; and last year I did my first season hillclimbing and time just disappears maintaining and trying to improve the TR4 road car I have, but it will get done. I have many more photos of 883GOH which I can share with Gerald, just PM me Regards Len
  3. I am sure that the length of the pushrod has very little effect on the rocker geometry. The rocker arm rotates around the rocker shaft, which is inserted/fixed to the pedestals, which are then bolted to the head, and so the rocker shaft is in a ‘fixed’ position on top of the head; and I think, at what height it is bolted - this sets the rocker geometry. We can change the height of the rocker shaft by removing metal from the base of the pedestals, or raising the pedestal height by putting shims under the pedestal. Skimming the head does not effect the rocker geometry as nothing changes on the topside of the head where the rockers are bolted down, it’s just that after skimming the head, the top of the head is now closer to the cam shaft, and so the old pushrods are too long Interestingly, I’ve measured the distance between the rocker shaft axis and the adjustment ball, and with the ball adjuster fully adjusted up or in (most threads showing above the rocker), this distance is the least (and so the best rocker ratio); and adjusted out the 7 full threads, this distance increases by 33 thou. Not much but it does alter the rocker ratio from 1.55 down to 1.50 if the adjuster is fully out (just enough thread left for the nut). So presumably the rocker adjustment screws need to have as many threads as possible showing where the nut is to have the best rocker ratio, I think this is where you would also get the least side to side movement of the pushrods in their vertical motion Still not decided what height to put my rocker shaft axis! Len
  4. Thanks Ian - Got Kastner's books too, he does concentrate on the pushrods more than the rocker geometry Can anyone explain how do the geometry on the Rocker axis and the shoe radius stuff on Ed's link? My maths is good - but 'O' levels were a long time ago to work out that geometry! The result might give an axis point a little above the 'mid-lift point' - which I would feel happier with, as I always felt 50/50 or mid-lift was too low a position for the start of the rocker register wiping action Thanks Len
  5. That's a good link Ed - thanks -not seen that before. The pic shows why midlift is ideal, and also why that will give me the minimum side movement of the pushrods - if I get the length right. The pic shows the wipe action going out and then back across the valve stem; with a 4.5 to 5mm wipe area visible on a the vavle stem and rocker register, am I right in thinking makes the rocker arm actually increaes in length by 4.5 to 5mm so it will wipe one way opening the valve and then wipe back as it closes -is that right? Richard - I can understand the idea of putting shims in will maintain the same pushrod length, but the rockershaft - I think - will then be 2.54mm higher than standard, so will probably put the rocker geometry out further from my ideal. The valves are still in roughly the same place, and nothing has been changed on top of the cylinder head, so rocker geometry would be close to how Triumph designed it - wouldn't it? Which in those days I think the rule of thumb was rockershaft 1/3rd down and 2/3rds up (compared to the valve movement) Thank you guys - my apologies for not signing off earlier! Len
  6. Hi I'm setting up my rocker geometry on (what will hopefully be) a fast TR4 rally car (10.4 compression ratio, RTR rally cam, light flywheel, webers etc) . I am using standard rockers with a tuftrided shaft and spacers not springs; where do I set the Rocker shaft height? Some say at exactly 50% of valve lift, another I’ve read suggests 40 to 50% down from the valve tip (is this allowing for the almost 5mm of wipe area we have and the rocker arm effectively increasing in length as it increases valve lift? – so increasing the rocker ratio) , and others comment on only adjusting the pedestal height to get the correct swipe pattern on the valve tip (to avoid valve guide wear). I calculate my valve movement is 11.46mm, so 5.73mm rocker height (down from the valve tip) might be ideal geometry? (assuming a rocker ratio of 1.55 to 1, and cam lift is 0.291”) Aiming for this, I have shaved/filed the base of the pedestals down so the rocker shaft is now 4.7mm down from the top of the valve (within the 40 to 50% -2nd theory!). However, looking at the rocker now touching the valve with the valve in the closed positon - the rocker’s wiping part (register) is close to the rocker side of the valve stem - see attached photo. I think if I shave the extra 1mm from the pedestals for a 50/50 rocker height, my rockers will be right on the edge of the valve; so is an option to grind and so round the inside part of the new rocker register to move the contact point away from the valve edge? My plan is to get the rocker geometry set up as best I can, then get a set of pushrods made the correct length for this particular engine – perhaps we can discuss pushrods later too; but I need a bit more understanding of the correct geometry and best TR practice please Any help or discussion would be appreciated
  7. Leno

    TR4 on weber 45s

    I've got SU's and want to change to webers so if you want to change let me know. My SU's do have different needles as engine is reasonably warm! - but I expect your car is not standard if someone has previously put webers on it Len
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