Tom1809 Posted December 25, 2014 Share Posted December 25, 2014 After a few drinks today the brain isn't really up to speed but still throwing ideas around and has raised a question. Theoretically speaking if you was to rotate say a v8 with zf box and lt230 the other way round so it's now a rear mid engined set up. Apart from the the diffs and output shafts been in the wrong place would it be a case of just swapping the diffs around to keep forwards forward? Other option I guess would be to run a rear wheel drive flange on the box and divorced transfer case to keep the correct placement of propshafts to axles and use the transfer case to keep the correct direction. Or is my thinking above compeltly a waste of time and that direction of travel won't be affected? Cheers Tom Quote Link to comment Share on other sites More sharing options...
Soren Frimodt Posted December 25, 2014 Share Posted December 25, 2014 You could flip the LT230 and drive it through the PTO hole. However rear engine isn't really beneficial unless all you do is go fast. For climbing offroad its useless Quote Link to comment Share on other sites More sharing options...
Tom1809 Posted December 25, 2014 Author Share Posted December 25, 2014 Now I hadn't though of that. I assume you would still get the correct direction of travel with it and could keep everything else in its place and wouldn't have to swap diffs around. Yes I understand for winch challenges it wouldn't be ideal but speed events it would be perfect set up. Quote Link to comment Share on other sites More sharing options...
RedLineMike Posted December 25, 2014 Share Posted December 25, 2014 wouldnt quite say perfect set up, but it works, its easier to have a front engine mid mounted with a long wheelbase & save all the work in flipping the axles/ diffs Quote Link to comment Share on other sites More sharing options...
western Posted December 25, 2014 Share Posted December 25, 2014 Look at a pre 300tdi 4 cylinder 90 or 110, they are virtually mid engined as the front of the engine is behind the front axle centre line Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted December 25, 2014 Share Posted December 25, 2014 You need to flip axles and re weld brackets back on so all lines up with new to flanges Exhaust us fun to sort too lol 1 Quote Link to comment Share on other sites More sharing options...
robertspark Posted December 25, 2014 Share Posted December 25, 2014 I'm sure I've seen a rear engine mounted challenge truck Quick search of the net reveals that the tomcat can have a rear mounted engine .... Is this sort of what you were on about (The thinking fluid has defiantly been flowing just don't get the chain block and grinder out till the hangover has past) Quote Link to comment Share on other sites More sharing options...
Tom1809 Posted December 26, 2014 Author Share Posted December 26, 2014 certinaly correct plenty of thinking fluid today lol and there's going to be no grinders or chain blocks for a little while as I'm still planning the design of the truck that I would like to build to enter in the ultra 4 Europe series and some other events that are more aimed at fast sections with a bit of water and mud. Not really going to be a winch challenge truck as a 300tdi tray back with 3 winches lockers etc would be pretty capable in the right hands. But from what I've seen over the last year is those style trucks arnt competitive compared to the buggy that Levi Shirley raced but it's two different disciplines. The idea for a rear engined racer came from endless hours of searching the net looking at the trucks that race in America and Australia and the rear engine concept is rather common. Now going back to sorens surgestion of running the lt230 through the PTO hole would I still have to flip the diffs or would It be easier to modify the transfer case. Quote Link to comment Share on other sites More sharing options...
robertspark Posted December 26, 2014 Share Posted December 26, 2014 If you ran the lt230 through the pto hole no the diffs would not need flipping (given the transfer case is still facing the right way). (Sorry I would not know where to start out of my league but I'll get the popcorn and watch with interest) Quote Link to comment Share on other sites More sharing options...
missingsid Posted December 26, 2014 Share Posted December 26, 2014 There are lots of rear engined racers in the UK, QT used to provide a service to chop axles but this may just be for caster correction. Milner Offrad have reverse rotation transfer boxes. If you want to see what a rear engine racer is like watch pretty much any UK racing video where the racer goes end over end! There is a famous one that even made it on to Fast an' Loud where the yank commentator claimed the roll as a front end dive, it wasn't, the only problem with rear engine racers is that the rear mass tries to overtake the front when it is airbourne! Think 911 in a corner and back off the gas, it will spin for the same reason. All the major and very painfull end over end rolls in the UK are rear engined. Another consideration is that most rear engine racers on LR chassis are cut and shut with two front halfs welded together to sort out the suspension etc, also the grar pattern is reversed and the gear lever is behind the driver so needs to be extended forwards. Of course there are benifits otherwise there would not be so many built but not just a simple job, we chose to move the engine and gearbox back instead for a RRC this is just a swap of prop shafts front to back and with an LT95 a short 101 bell housing but this was in the 90's! Quote Link to comment Share on other sites More sharing options...
Lewis Posted December 26, 2014 Share Posted December 26, 2014 Moglite was rear engined, maybe there are still some pics hosted online somewhere Quote Link to comment Share on other sites More sharing options...
miketomcat Posted December 26, 2014 Share Posted December 26, 2014 Moglite was but Andy never really did much with it. It was a whole load of work that didn't seam to gain much and it definitely didn't go fast though that was mainly down to axle issues. Not sure where it went in the end. My tomcat was disco based we moved the engine back 10" this swapped the props front to back the engine ended up about 4" behind the front axle. It drove and handled very well on and off road. If I did it again I would use a defender lt77 not a disco one though as this would even the prop lengths up I ended up with a disco 2 front prop on the rear to stop vibration. Mike Quote Link to comment Share on other sites More sharing options...
Team Idris Posted December 26, 2014 Share Posted December 26, 2014 I've seen rear engine vehicles behaving badly on jumps as well. Maybe it is because beach buggy's and sand rails have absolutely no weight up front that they don't try to flip end over end like rear engine 4x4's? It does look like a vertical version of Porshe syndrome. It seems less of an effect on that ford focus and the pugot's. So in a way you could say; where do you want to sit in your mid engine 4x4' at the front like a focus, or at the back like a Thug? Saley's winch truck is rear engine. No noticeable difference to the Beast except it's longer. The rear engine doesn't make it kick ass or suck to any visible amount. But it does look a load easier to work on In my mind it can flip the front axel up onto stuff easier. The Beast likes to plough-on due to front winch mass. I'd be less inclined to flip the V8 as it is already light weight. I have rad, batteries and fuel in the back, and it isn't too far off. Afterall, the gearbox set is as heavy as the engine, if not heavier ? Quote Link to comment Share on other sites More sharing options...
Tanuki Posted December 26, 2014 Share Posted December 26, 2014 Surely you could just move the existing engine/transmission from the front to the back, and use a long prop to the front/short prop to the rear setup? I'm sure that in a 127 or 130-inch chassis it could be made to fit though the front-end of the engine might need to poke through the rear bulkhead a bit. [Longest-possible-wheelbase is good for stability at speed: compare an arrow to a cricket-ball and see which one's the most likely to tumble end-over-end] Quote Link to comment Share on other sites More sharing options...
Tom1809 Posted December 27, 2014 Author Share Posted December 27, 2014 Problem is everything is a compromise as a longer chassis and wheel base will decrease break over angle and cause more issues in the rocks. The plan is to try and create something around the 100" wheel base that's is a reliably and easy to work on. I have a ls3 and box I could throw into the truck but I don't think that is the right way to go and would rather build something to a budget and make a decent chassis and suspension geometry cause axles can be changed so can the drive train at a later date. Off to do some more research on the advise you have given me. Cheers Tom Quote Link to comment Share on other sites More sharing options...
RedLineMike Posted December 27, 2014 Share Posted December 27, 2014 To be fair, 100" wheel base is now too short, mine is 100 & next truck will have 108 Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted December 27, 2014 Share Posted December 27, 2014 I had a rear engined strange rover 5.7 v8 Chevvy engined racer - it was very tail happy and very unbalanced Mid or front "Balanced" is a better option LOTS of work, lots of money, lots of special bits.... If I was doing it now I would prob go 110 inch and pull engine back a large amount of inches to have it balanced in the middle, Quote Link to comment Share on other sites More sharing options...
Tom1809 Posted December 27, 2014 Author Share Posted December 27, 2014 The balance is something I'm trying to get my head around and work out along with suspension geometry. it would be very easy to build a cheque book racer and get a company to build it. I'd rather build something myself and learn as I go. Got a lot of years in me and I'm sure over the next years what I build now will be totally different. I know my way round a v8 and mega squirt thanks to nige and I'm considering a 4.6 instead of the ls3 coupled with a zf4 speed and lt230 as the drivetrain. Once I start the build ill make sure I Will keep a updated blog of it, Cheers Tom Quote Link to comment Share on other sites More sharing options...
Daan Posted December 27, 2014 Share Posted December 27, 2014 You could flip the LT230 and drive it through the PTO hole. However rear engine isn't really beneficial unless all you do is go fast. For climbing offroad its useless You'd still need to change the rotation direction. I would flip the axle upside down to get the diff on the opposite side and change the rotation. Or ditch the beam axles completely and go independant. Daan Quote Link to comment Share on other sites More sharing options...
miketomcat Posted December 27, 2014 Share Posted December 27, 2014 Aren't p38 axles the other way round just a thought don't know anything about them mind. Mike Quote Link to comment Share on other sites More sharing options...
Team Idris Posted December 28, 2014 Share Posted December 28, 2014 Going independent is an interesting plan, even if it is only on the front. My mates Vit handled way better than my RRC buggy. You could spend a lot on the front axel, near nothing on the rear or transmission and have a very good vehicle. If you are handy with a welder, the only real problem is the front diff assembly. (locker or not). Quote Link to comment Share on other sites More sharing options...
elbekko Posted December 28, 2014 Share Posted December 28, 2014 Aren't p38 axles the other way round just a thought don't know anything about them mind. Mike The diff is on the other side, but direction of rotation is still the same (I think). Quote Link to comment Share on other sites More sharing options...
Lewis Posted December 28, 2014 Share Posted December 28, 2014 The only axle and transfer box I know of which turns the opposite direction to conventional is the G-wagon Quote Link to comment Share on other sites More sharing options...
Disco1tdi Posted December 28, 2014 Share Posted December 28, 2014 Have a look at what Dave Billings of Tornado Motorsport does. He makes a mid/rear engined comp safari vehicle, using flipped axles. (It's the Evo 3 model). Quote Link to comment Share on other sites More sharing options...
Tom1809 Posted December 28, 2014 Author Share Posted December 28, 2014 I will admit indy front is probably out of my league on this build unless I either pay someone to make it for me or I find someone who is willing to help and fabricate it in return for free beer and workshop space. Flipping the axles wouldn't be a issue. I'm going to put pen to paper and some sketches and see what you guys think. Quote Link to comment Share on other sites More sharing options...
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