v8bobber Posted March 7, 2008 Share Posted March 7, 2008 hello all, I posted a couple of questions a while back about building an 80" trialler with a 200tdi and manual box. However, it now seems that after doing some measurements i'm not going to get three pedals in the pedal box and will more than likely need to go the auto route anyway. Seemed a nice idea at the time but I will buy a donor vehicle with a V8 and auto combination My question is, what combination of v8 and auto box is the most compact to give me the best rear propshaft length? Ideally the box would be something that is fairly easy to come by. Also, not knowing very much about auto boxes. Is is possible to "lock" them in gear so it drives like a clutchless manual? Hope someone can advise, Dave Quote Link to comment Share on other sites More sharing options...
88 Nick Posted March 7, 2008 Share Posted March 7, 2008 Hi Dave, There's a guy across the road from me who's just built an 80"v8 auto,he kept the engine mounts in the origional position instead of moving everything back like a lot of people do,he's done a few trials with no prop problems as yet. He went for the viscous transfer box,some trialers favor these as you can apply gentle handbrake and tighten your turn,Ive gone the other way on my challenge motor and swapped the viscous for an lt230. IIRC the rear prop is the same length for either box but the front ones about 50mm shorter for the viscous jobbie. You can lock the box in first and get some engine braking but its nothing like a locked in gear manual,it is possible to have boxes built that do lock in gear without the torque converter effect but ££££££££££££. When I first trialed an auto I got penalised afew times for loosing forward momentem but that was just carp driving....... having said all that I woudnt have anything else now! Nick Quote Link to comment Share on other sites More sharing options...
v8bobber Posted March 7, 2008 Author Share Posted March 7, 2008 Cheers for that Nick. I dont suppose you know what autobox it was? Dave Quote Link to comment Share on other sites More sharing options...
88 Nick Posted March 7, 2008 Share Posted March 7, 2008 Dave, The box is the borg warner HP 22 Four speed,its been in all the Rangies And Disco's since the Chrysler 3 speed disapearerd ages ago,if your going to pick up a 3.5 or 3.9 efi auto doner vehicle this is the box it will have,the only cheap upgrade you might whant to consider is a HP 24 from a Jag or BMW,only slightly longer and has bigger oil pump and clutch packs,not really worth the aggro in a trials motor in my opinion though. The other thing worth thinking about is cooling,it wont be a problem if your just doing short burst trial sections but I Have cooked one box on a challenge. Nick Quote Link to comment Share on other sites More sharing options...
Night Train Posted March 7, 2008 Share Posted March 7, 2008 Slightly OT but I've always fancied the idea of having engine, torque converter, clutch, manual gear box, transfer box as a set up. Great for towing. Didn't Ian Ashcroft used to do selectable Auto boxes at a reasonable exchange price? Quote Link to comment Share on other sites More sharing options...
v8bobber Posted March 7, 2008 Author Share Posted March 7, 2008 Cheers for that Nick, I think I know the autobox you mean now. And you think this will be of a suitable length to run a good length rear propshaft. Is this longer or shorter than the series / Lt77 set up (manual) do you think? I'll be honest, i;ve never been a fan of auto boxes, but I can see the advantages especially in trialling as you can't stall em! I've always trialled manuals in the past and yes it's a good way to learn but the auto i suppose will give you the edge. I don't suppose your mate across the road knows how long his rear propshaft is? I don't want to limit the rear travel too much because of the minimal length of the propshaft? I take it i need to look for a 3.9 RR auto donor vehicle then? Dave Quote Link to comment Share on other sites More sharing options...
88 Nick Posted March 7, 2008 Share Posted March 7, 2008 3.5 or 3.9 will do you theres plenty about,I'll have a word about prop lengths and any other issues he encounterd and let you know, in fact when ive checked with him i'll pm you his phone number. Nick Quote Link to comment Share on other sites More sharing options...
v8bobber Posted March 7, 2008 Author Share Posted March 7, 2008 Just looking on ebay, where does the ZF auto box come into the equation, i'm assuming this is different to the borg warner box? Dave Quote Link to comment Share on other sites More sharing options...
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