garrycol Posted November 28, 2012 Share Posted November 28, 2012 Hi All - some questions for the learned gathering - some of the answers may already exist but I cannot fins them. Background I have a 101 and am looking to replace the 3.5 with a 4.6. I have acquired a top hatted low compression 4.0 and also have a liner slipped low compression 4.6 block, crank and pistons. I am putting the 4.6 crank and conrods into the 4.0 but using the LC 4.0 pistons as the result is a comporession ratio just a bit less than HC 4.6 pistons. I am going no ditributer so in its simplest form will have a Megajolt ingnition and up speced carbies off the 3.5. The engine will be getting a mild cam to improve mid range torque - mainly due to the high revving nature of a V8 in the 101 at cruising speed. HOWEVER I also have a dead 3.9 that has its Gems manifold, plenum, and injectors still on it, so using this with a MS to run everything is an option. Also I can get a Thor manifold, plenum and injectors for a very good price. Another option. Question The simple question for the brains trust - which injection system should I put on the new 4.6 - Gems or Thor and are there any issues with MS runnning either. Also can the crankshaft indicator on the 4.6 be used instead of the MS/MJ crankshaft wheel to send crankshaft pluses to the MS/MJ ECU. Thanks Garry Quote Link to comment Share on other sites More sharing options...
elbekko Posted November 28, 2012 Share Posted November 28, 2012 I'd go for GEMS plenum, much easier to get to the injectors etc! The Bosch intake really is a monstrosity Quote Link to comment Share on other sites More sharing options...
HoSS Posted November 28, 2012 Share Posted November 28, 2012 I used Thor on mine. No issues with MS. The reason was that from research the long leader tubes on thor are supposed to give better low torque (at the expense of high rev flow) but thats perfect for a 4x4. Thats an ex-carb 3.5, with a thor manifold on top and MS. Quote Link to comment Share on other sites More sharing options...
elbekko Posted November 28, 2012 Share Posted November 28, 2012 To me the biggest downside of the Thor manifold is access, you can't reach the injectors if you want to test something etc. Quote Link to comment Share on other sites More sharing options...
garrycol Posted November 28, 2012 Author Share Posted November 28, 2012 Thanks for those great topics - the 101 revs at just under 4000rpm at 100kph and at this speed the 3.5 really lacks torque and dies on any hills. Low down torque is fine. By going to a 4.6 I am looking at better torque across the board and I am putting in a cam to increase torque at up to 4150rpm. So for my needs the Gems might be better torque at the lower end will what I need where the Thor may reduce it at cruising speed. If I go Gems I might get away with the standard ECU and use MegaJolt for the ignition. Cheers Garry Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 28, 2012 Share Posted November 28, 2012 TBH the 4.0/4.6 is not going to be any happier screaming round at 4krpm, I'd look at overdrives or bigger tyres to drop the revs a bit. I'd vote Thor, it's not that complicated and does gain you ~20lb/ft or something like that. Injectors etc. can be either, it's only the top bit that's really different. Quote Link to comment Share on other sites More sharing options...
garrycol Posted November 28, 2012 Author Share Posted November 28, 2012 TBH the 4.0/4.6 is not going to be any happier screaming round at 4krpm, I'd look at overdrives or bigger tyres to drop the revs a bit. I'd vote Thor, it's not that complicated and does gain you ~20lb/ft or something like that. Injectors etc. can be either, it's only the top bit that's really different. A 101 already runs 35" tyres as standard so going larger is not really a option both legally and power wise with the 3.5v8. I already have an overdrive and the 3.5 can only pull it on the level or going downhill. Top spped is about 15kph slower with O/d in. One of the reasons in going the 4.6 was to get the torque to pull the O/d, higher transfer case gears or even bigger tyres as you suggest. I am looking to increase cruising speed to about 100kph (while the 3.5 does 4000rpm at 100kph it cannot cruise there if there is any incline) while decreasing revs to around 3000rpm but you need the torque to do that. You say the Thor gains around 20 ft ibs but at what revs?? I do not need it low down as long as the 4,6 will match the 3.5 below 2000rpm (or hopefully be better). Cheers Garry Quote Link to comment Share on other sites More sharing options...
elbekko Posted November 28, 2012 Share Posted November 28, 2012 I think the 4.6 will happily pull it along with higher gears, what diff gearing does it have? Perhaps you can play with that. Quote Link to comment Share on other sites More sharing options...
Quagmire Posted November 28, 2012 Share Posted November 28, 2012 To be honest after ditching the SUs on my 3.5 for an Ms'd flapper top end the difference has been remarkable. Should be ok with either. I imagine the Thor will be much harder to work on in a 101 as its quite hard to get to the sides of the engine normally! but does Thor reduce problems you have with the normal plenum being in the way of gear stick? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 28, 2012 Share Posted November 28, 2012 Thor gains low-down torque. Considering how hobbled the carbed 3.5's were in anything but the RR, pretty much anything you find will pull better, especially when MS'n'S'd. I would ditch the carbs, otherwise you're knocking a load of driveability and economy off of your efforts - two steps forward, one back. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted November 28, 2012 Share Posted November 28, 2012 3.5 RRC Carbs: 135BHP, 3.5RRC Flapper injection: 155BHP, no question in my mind which I would go for between carb and EFI, and that's on the rubbish that LR fitted originally! Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 28, 2012 Share Posted November 28, 2012 In my experience also: Holley carb < Standard Carbs < Weber Carb < Flapper EFI < Megasquirt < MS'n'EDIS Quote Link to comment Share on other sites More sharing options...
garrycol Posted November 29, 2012 Author Share Posted November 29, 2012 3.5 RRC Carbs: 135BHP, 3.5RRC Flapper injection: 155BHP, no question in my mind which I would go for between carb and EFI, and that's on the rubbish that LR fitted originally! I agree and that is not the issue - it is which injection system to go for. I think the 4.6 will happily pull it along with higher gears, what diff gearing does it have? Perhaps you can play with that. The diff ratios are 5.7:1. Going to 4.7:1 causes drivability issues in low range. I imagine the Thor will be much harder to work on in a 101 as its quite hard to get to the sides of the engine normally! but does Thor reduce problems you have with the normal plenum being in the way of gear stick? I haven't checked that out at this stage - the Thor certainly looks wider than the GEM but not sure if it as high. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 29, 2012 Share Posted November 29, 2012 You could swap the transmission for a later Range Rover setup, that gives you an LT230 with choice of 1.004, 1.2, 1.4 or 1.6 :1 ratios and low box would be super-low as it's designed for 3.54:1 gearing in the axles (albeit with smaller tyres). My gearing is very similar to yours; I have a 4.6 V8, R380, 1.003:1 LT230, and 5.99:1 in the axles (Volvo) with ~36" tyres. 100kph is very doable, sits about 3100rpm, and low range is lovely and low. Quote Link to comment Share on other sites More sharing options...
garrycol Posted November 30, 2012 Author Share Posted November 30, 2012 While there is a lot of commonality with the 101 and earlier RR and Stage 1s, there is a lot that is unuque. The short wheelbase and high lift already cause issues with driveshaft angles and that is with the unique 101 LT95 that has a shorter input shaft and bellhousing the make the gearbox unit as short as possible. An R380 an LT230 combo would be great but it is just too long - also it does not have the PTO arrangement to run the 101s standard Noken winch. Likewise low range is no where near as low as the 101. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 30, 2012 Share Posted November 30, 2012 garry - a different transfer box would not change drivetrain angles. 101 is 1" longer wheelbase than a RR so you shouldn't have an issue there, although driving the winch could be tricky. LT230 low-range is 3.32:1, same as the LT95, only difference with a 5-speed is the 1st gear is ~3.7:1 depending, rather than the 4:1 of the LT95. Most of the gearing weirdness of the 101 is the low-ratio axles and big tyres. Assuming you stick with the LT95, according to this page, you can pop the gears from a RR in to gain high-range gearing which sounds worth a go and would give you gearing slightly higher than me. Quote Link to comment Share on other sites More sharing options...
garrycol Posted November 30, 2012 Author Share Posted November 30, 2012 garry - a different transfer box would not change drivetrain angles. 101 is 1" longer wheelbase than a RR so you shouldn't have an issue there, although driving the winch could be tricky. LT230 low-range is 3.32:1, same as the LT95, only difference with a 5-speed is the 1st gear is ~3.7:1 depending, rather than the 4:1 of the LT95. Most of the gearing weirdness of the 101 is the low-ratio axles and big tyres. Assuming you stick with the LT95, according to this page, you can pop the gears from a RR in to gain high-range gearing which sounds worth a go and would give you gearing slightly higher than me. As the LT95 is a gearbox/transfer case is a combined unit in one housing it is not really viable to cut off tranfer case and develop an adaptor plate to mount an LT 230. If I was to use a R380/LT230 combo (which is a lot longer than the 101 LT95) the engine will have to move forward and that will mean cutting into body work at the front and moving controls etc - in reality all too hard - or I have to move the gearbox back that will cause problems with rear driveshaft angles. Also the 101 is the equivalent of a standard Range Rover with a 4" lift and if the RR is lifted that much it would also have a problem with driveshaft angles - hence placement of the transfer case within the 101 chassis is important - as it is the 101 driveshafts work outside UJ design limits and causes the "101 Rumble" where the front driveshaft rumbles at 80kph on trailing throttle. The bottom line is that the 101 was never deigned for highway cruising at moderately high speeds and out of mil service we are asking it to do exactly that. The 3.5 just does nor have enough puff to do this where the 4.6 should be OK. As that link you highlighted showed, it is not viable going up in diff ratio but higher speed hi range gears and overdrive is - the 3.5 will pull either is some conditions but not both together hence the change to a 4.6. With O/D and hi speed gears fitted I should be able to down to a bit less than 3000 rpm at 100kph and have the torque to pull it. That is why I am not looking to increase torque of the 4.6 at the low end (as long as the 4.6 has more torque than the basic 3.5 at the bottom end) but get as much torque as I can up around the 3000-4000rpm range. On the Gems vs Thor issue it would seem that Gems will do this a little better (and I have most of the parts) than Thor and will not be as wide when fitting into the engine compartment. Cheers Garry Quote Link to comment Share on other sites More sharing options...
Quagmire Posted November 30, 2012 Share Posted November 30, 2012 Whatever you do decide to do, I want to see lots of pictures! We have been contemplating efi on my Dads but haven't got round to it yet... Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted November 30, 2012 Share Posted November 30, 2012 Is a stumpy R380 still too long compared to the LT95...? Quote Link to comment Share on other sites More sharing options...
garrycol Posted December 1, 2012 Author Share Posted December 1, 2012 I am not sure but you cannot run the winch from a LT230. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted December 1, 2012 Share Posted December 1, 2012 Well, you can get PTO's, they just don't turn up very often, at least over here. Some countries they fit loads of them for various reasons. Quote Link to comment Share on other sites More sharing options...
garrycol Posted December 2, 2012 Author Share Posted December 2, 2012 Well, you can get PTO's, they just don't turn up very often, at least over here. Some countries they fit loads of them for various reasons. The 101 pto does not go fore and aft like other land rover ptos - they go out sideways under the chassis to the winch which is mounted on the outer chassis midway between the wheels. The winch is not fitted to the front like most other landies. As far as I am aware there is no similar pto on the LT230, indeed there is no other LT95 PTO that is similar to the 101 pto.. Quote Link to comment Share on other sites More sharing options...
garrycol Posted December 2, 2012 Author Share Posted December 2, 2012 I hope I am not sounding too negative to suggestions. As I indicated ealier, while the 101 has a lot in common with other Landies there is lot that is unique eg suspension/axles, wheels (6 stud vs 5 stud), bell housing, ptos, steering and it goes on. I have had a 101 on the road for quite a few years now and have investigated just about all the mods that could be suggested. Anything is possible at a price but will require major modifcations. A 4.6 is essentially a bolt on modification that would not even be noticeable if I used Carbs. Thanks for all the input. I will most likely go Gems as I have many of the bits and it does seem to deliver the torque I am after. The issue will be whether I go the original 4.6 Gems ECU or Megasquirt. If I do go the original ECU then I will just be looking at MegaJolt to run the ignition and looking at petrol and LPG maps. Cheers garry Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted December 2, 2012 Share Posted December 2, 2012 I hope I am not sounding too negative to suggestions. I was about to say the opposite - I hope I'm not sounding like I'm ignoring your preference - just trying to point out what's possible. I'd vote MS, but I'm biased I reckon it's less wiring, less fussy, and if you're going MJ then it's a very small step really. Quote Link to comment Share on other sites More sharing options...
dirtydiesel Posted December 2, 2012 Share Posted December 2, 2012 You will find that your biggest restrictions on your 101 are the stromberg carbs and the standard exhaust manifolds. In your shoes i'd be fitting the thor manifold probably to the stock 4.0. (i've allways prefered the way 4.0's rev over 4.6's) all on megasquirt. then i'd be fitting a set of rangerover high ratio gears to your transfer box as the new engine will pull the gearing with ease. the rangerover gears are still available genuine for very reasonable money. your diffs by the way are 5.57:1 Quote Link to comment Share on other sites More sharing options...
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