Gridgway Posted February 4 Share Posted February 4 As I work through my 80s BDR to get it back on the road, I knew that the floor panel under the gearbox looked odd. Now I should have paid more attention to it in the investigation stage, but anyway yesterday in a fit of cleaning, I got underneath and set to with my duck oil and rags. That's by the by, it was time to see what was going on. The pic below shows it. The engine and box have been fitted about 1" further back in the chassis. You can see the gearbox mount bolts on the right as it were in the pic and those three bolts on the left. Looking from above quite some engineering has gone on to do this with a new plate made up. The old cross member has been partially cut away and the plate has upside down L sections on the end to rest on the remaining ends of the cross-member. It got me quite anxious for a while, but nothing has moved, bent or cracked so it looks strong enough. I'll try and get a picture of the arrangement. Looking at the clearance at the front of the engine it's less that an inch so the BDR motor wouldn't have fitted otherwise. The motor is as far back now as it can be with a small amount of clearance between the bell-housing and the driver's foot area panelling. So all very curious, but I can't see that the engine would have fitted any further forward. I'm assuming that there was previously a crossflow in there as the BDR was built in 2001 which is when it must have been fitted. And to add, I'm now assuming that a shorter propshaft must have been used. At the back there is a spacer about 3/4" thick and the other end doesn't look like it's as far in to the gearbox as it might be. What great fun! Anyone shed any light on matters here? Link to comment Share on other sites More sharing options...
7 wonders of the world Posted February 4 Share Posted February 4 Type 2 4 speed and Type 9 (5 speed) or Type E Rocket have different mounting points, not sure what box you currently have but it seems likely it's have a different box at some point. Link to comment Share on other sites More sharing options...
7 wonders of the world Posted February 4 Share Posted February 4 just looked at the photo again the holes aren't far enough apart for my previous thoughts which were in the region f 100mm Link to comment Share on other sites More sharing options...
Gridgway Posted February 4 Author Share Posted February 4 This box is the type e rocket box. I also have a type 2 which is the same distance 18 inches odd from bellhousing to mounting bolt. I need to compare the engine mounts from my flow 7 to make sure they are different as it were When I was investigating the chassis to see if it was a proper Arch one, Bruce described it as a Vegantune chassis I think. I should have asked more. Anyone heard of that as a chassis derivative? Link to comment Share on other sites More sharing options...
Tony P Posted February 4 Share Posted February 4 (edited) From memory, the Vegantune engine was a short-lived option to replace the no-longer-available Lotus Twin-cam (but based on the same engine architecture - and, I assume, the same block casting?). I don’t remember ever seeing one (at least not a close inspection) but I’d have thought any differences in dimensions (i.e.length) were down to ancillaries or bellhousing etc, or a different gearbox rather than the engine having been moved back, especially as you say there is no space for an engine to have been any further forward. EDIT: Ah… according to ‘Coulter’ (a reliable Seven ‘bible') there were three versions of Vegantune engine used: 1) their version of the Lotus Twin-cam (essentially the same spec) 2) a similar unit built on the taller 225E block (resulting in an extra 40cc) 3) the VTA, also on the 225E block, but with belt-driven cams like the BD Though that doesn't help much - - not immediately clear to me what differences in the chassis that would require - Bruce would surely be the best source for info on that… It seems the Vegantune-built engine was done for first by a lack of the original blocks, hence the switch to the 225E, then Lotus running out of Twin-cam heads. As an aside, early problems with (and subsequent unavailability of) the Vegantune engine prompted development of the twin-carb Kent (‘crossflow’) engines - the Supersprint version leading in turn to the enlarged 1700 version of Cosworth’s 1600 kit engine, the BDR. Neither ‘Coulter’ nor ‘Weale’ appear to suggest what, if any, drivetrain mounting changes were required. So… sorry, no help there, but hope the background might be of interest. Edited February 5 by Tony P Link to comment Share on other sites More sharing options...
Nigel Blandin Posted February 5 Share Posted February 5 Is yours a short, live axle chassis? Caterham seemed pretty fixed on motor position, so adapted things around the gearbox to suit. My BDR has a 35mm spacer to the type 9 box to get things lined up….I wish they had shoved the motor back instead- it is so tight to get in and out, I have to remove the bottom pulley to do this. Link to comment Share on other sites More sharing options...
Gridgway Posted February 5 Author Share Posted February 5 Yes, short, live axle. I've not had the engine out yet to see how tight that is! I'll do some measurements against my 90's long cockpit LA caterham chassis to see if the distance between the engine mounts and gearbox mounts is the same. If I'm right that the motor has been moved back, then the engine mounts must be bespoke for that to happen. They are certainly different to the other one. Link to comment Share on other sites More sharing options...
Gridgway Posted February 5 Author Share Posted February 5 So I have compared the lower chassis tubes between my 90's long cockpit LA and the 80''s short cockpit one. The first pic is the later car (helpfully there's no motor). The second two pics are from the BDR (unhelpfully) from underneath. You can see that the cross tube joins the side further back in the car and then there is a radiused tube around to the front. If that is what the "Vegantune" chassis is about (and I think it is) it looks like it was giving more room at the bottom for some reason. Was it a tall motor with the Vegantune head by any chance? I should just phone Arch and ask! I don't think this has any bearing on the fore and aft position of my BDR motor though! Link to comment Share on other sites More sharing options...
OldAndrewE Posted February 5 Share Posted February 5 Don't know if this pic is any help Graham but this is my 1985 short cockpit LA chassis (freshly back from Arch). It has a 711M crossflow and a 2000E gearbox. When I got the chassis from Caterham it had the fitment for the Escort Sport box that I removed the upper part from to enable fitting the 2000E Link to comment Share on other sites More sharing options...
rkeywood Posted February 5 Share Posted February 5 This might help: VTA info.pdf Rob Morley at Protune Racing is the go to for VTA info - he was, I think, the main engine man at Vegantune Link to comment Share on other sites More sharing options...
Gridgway Posted February 5 Author Share Posted February 5 34 minutes ago, rkeywood said: This might help: VTA info.pdf 4.07 MB · 3 downloads Rob Morley at Protune Racing is the go to for VTA info - he was, I think, the main engine man at Vegantune Thanks for the PDF - very interesting. The motor looks pretty much the same dimensions as the BDR, not obviously higher or anything. I'm probably just adding too many things together in my musings! Link to comment Share on other sites More sharing options...
Gridgway Posted February 5 Author Share Posted February 5 Lovely pic there Andrew. Your chassis has the same arrangement of lower tubes as mine then. Also on mine that upper round section tube that goes across in front of the engine is square section. When you say "it had the fitment for the Escort Sport box that I removed the upper part from to enable fitting the 2000E" what was the bit you removed? Link to comment Share on other sites More sharing options...
OldAndrewE Posted February 5 Share Posted February 5 Pic taken during strip down. I have marked in red the bit I removed, it was to take the gearstick that then connected to the Escort box with a linkage Link to comment Share on other sites More sharing options...
Gridgway Posted February 5 Author Share Posted February 5 Thanks Andrew, yes of course the wonderful remote gear linkage - I should have known that! Looking at your first picture the cross piece that the gearbox mount sits on has had the centre 2/3rds cut away and replaced with a plate for the mount to sit on. Link to comment Share on other sites More sharing options...
OldAndrewE Posted February 5 Share Posted February 5 Not quite sure what you mean there Graham. Apart from the bit already mentioned the chassis is exactly as it came from Caterham. Another pic of the gearbox mount taken during strip down below Link to comment Share on other sites More sharing options...
Gridgway Posted February 5 Author Share Posted February 5 Sorry Andrew was trying to describe the mod to the gearbox mount that has been done on my chassis Link to comment Share on other sites More sharing options...
OldAndrewE Posted February 5 Share Posted February 5 OK, I understand now Graham Link to comment Share on other sites More sharing options...
andy couchman Posted February 18 Share Posted February 18 Not sure if he's still a club member but in Gloucestershire we had a guy called Colin Chapman (no, not that one) and he paid a lot to have a Vegantune engine built. From memory he had issues with the engine but can't remember what. This was a good few years ago though! Link to comment Share on other sites More sharing options...
Gridgway Posted February 18 Author Share Posted February 18 Interesting. One of my outstanding jobs is to compare the distance between the engine mount holes on the chassis and the gearbox mount. I have a long cockpit LA Caterham to compare to. I'm still working on the assumption that the engine had to be moved back an inch to fit in for some reason. I must remember to do that to try and see what's what. They certainly went to a lot of effort to fabricate a new gearbox mount arrangement to get an extra inch! Link to comment Share on other sites More sharing options...
Tony P Posted February 19 Share Posted February 19 (edited) More on the the aforementioned Vegantune engine… The picture is from a road test report in the long-defunct ‘Automobile Sport’ magazine, forty-odd years ago.This is the ‘VTA’ iteration with their own twin cam heads (1600, two-valve on the slightly taller 225E block) in a live-axle (obviously), long-cockpit chassis. The square-section lateral tube ahead of the engine was a feature of S3 Lotus twin-cam engined era cars, so, comparing pics of those, it doesn’t appear that the VTA required any more space at the front than a Twink (for e.g. to clear its timing gear and requiring the drive train shifting) - if, indeed, the chassis in question here had been adapted for the VTA, a possibility hinted at upthread. The magazine article also reckons that the VTA was available “in sizes from 997cc to 1600cc”. I’ve never seen or heard of the smaller version in a Seven - or anywhere else. I do recall, way back when, meeting a handful of young owner-builders who had fitted 1300cc Xflows as it had made insurance more attainable, with plans to upgrade in the future. I suppose a one-litre, belt-driven twin-cam might have been an attractive proposition? Edited February 19 by Tony P Link to comment Share on other sites More sharing options...
Gridgway Posted February 19 Author Share Posted February 19 Thanks, that's very interesting and a great picture! I just went into the garage and re-looked. As it happens I also have a twincam just sat there as well. With a very rough measure, the gubbins on the front of the BDR sits about 2cm further forward than the equivalent on the twincam. In my BDR installation there's about 1cm clearance between the aforementioned gubbins and the diagonal chassis member in front of the engine. So it wouldn't have fitted if the engine hadn't been located an inch further back in the chassis (sorry for the mix of units!). Makes me wonder (again) how a BDR normally fits! Link to comment Share on other sites More sharing options...
OldAndrewE Posted February 19 Share Posted February 19 The square tube in front of the engine in the photo Tony posted appears to be forward of the 'normal' position. The wing stay clamp tubes are on top of this tube in a 'normal' chassis. Link to comment Share on other sites More sharing options...
Gridgway Posted February 19 Author Share Posted February 19 19 minutes ago, OldAndrewE said: The square tube in front of the engine in the photo Tony posted appears to be forward of the 'normal' position. The wing stay clamp tubes are on top of this tube in a 'normal' chassis. And thus the diagonal down from it must be further forward as well? Link to comment Share on other sites More sharing options...
Tony P Posted February 19 Share Posted February 19 Ah, so it does Andrew, thank you; I should have noticed that when comparing pictures. But if that was required to get fit the VTA in, that kind of suggests that there was no need to move the drive train backwards? Perhaps then the Vegantune thing is a red herring in the history of this chassis... Link to comment Share on other sites More sharing options...
Gridgway Posted February 19 Author Share Posted February 19 Yes I do think it might be a red herring! Link to comment Share on other sites More sharing options...
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