vulcan bomber Posted February 15, 2014 Share Posted February 15, 2014 The diaphram does affect top end performance. Quote Link to comment Share on other sites More sharing options...
dirtydiesel Posted February 16, 2014 Share Posted February 16, 2014 The diaphram does affect top end performance. If the boost aneroid is functioning correctly, once the diaphragm has been fully depressed (this happens somewhere around 10psi on a stock tdi pump) the lever arm has no effect on the governor rack. The only purpose of the aneroid is to de-fuel the pump from its Max fuel setting until the turbo is spooled. Quote Link to comment Share on other sites More sharing options...
Ex Member Posted February 17, 2014 Share Posted February 17, 2014 But the maximum amount the pin moves depend on the diaphragm orientation. Does that not affect the fueling on maximum boost? The pin is eccentric. Do you know of a source for springs to allow control above the 10 psi? Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted February 17, 2014 Share Posted February 17, 2014 Dave, put a 1.4 transfer box back on it. You'll get all the spriteliness back but you'll take a bit of a hit on economy. In the ideal world 1.4 transfer box and an overdrive is the best combination but that's a lot of expenditure to contemplate. Mo Quote Link to comment Share on other sites More sharing options...
reb78 Posted February 17, 2014 Share Posted February 17, 2014 The trouble with the OD that I found Mo was that the boost drops off in 5th +OD at 70 mph compared to 5th. It made it rather gutless in the cruising gear then. That was my main reason for fiddling with my FIP and boost. it's set now, so that can boost at 1 bar with the OD engaged on 5th, and now more driveable. (That reminds me, Neil is still storing that OD for me. I must check it's not in his way! Have you put yours back together yet?) Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted February 17, 2014 Share Posted February 17, 2014 Not a problem in a proper sized land rover Rich Quote Link to comment Share on other sites More sharing options...
Daan Posted February 17, 2014 Share Posted February 17, 2014 A solution is a pre tdi gearbox, like a diesel or turbodiesel. This would lower the 5th gear ratio from 0.77:1 to 0.831 > -8%. It would put it right between a 1.2 and 1.4 transfer box, which is +17%. Worth a punt I reckon. More ratios: http://www.ashcroft-transmissions.co.uk/calc/ratio_calc.html Daan Quote Link to comment Share on other sites More sharing options...
vulcan bomber Posted February 17, 2014 Share Posted February 17, 2014 The TDi will also eat layshaft bearings of you drive it anything other than like a grandad. Quote Link to comment Share on other sites More sharing options...
Ex Member Posted February 18, 2014 Share Posted February 18, 2014 The TDi will also eat layshaft bearings of you drive it anything other than like a grandad. If you get a "G" suffix box, they are fine. I think even "F" is fine. This is what I'm running on my TDI. Quote Link to comment Share on other sites More sharing options...
honitonhobbit Posted February 18, 2014 Share Posted February 18, 2014 Why would you want to be doing 80+ in a 90/100/110? Beats me! Dave I would give the lump a bloody good service - when did you last re-con the injectors and set the tappets; clean out the 'cooler, change the vaporiser? Also have a good look at snorkel restrictions. Mo is right you know - although he only gets such appalling fuel consumption due to his right foot problems. My 110 will lose a stock TD5 90 up to 70 if I can be arsed, but if I drive it normally it'll do 35mpg day or night. So change back to the 1.44 and change your driving style to suit... Quote Link to comment Share on other sites More sharing options...
dirtyninety Posted February 18, 2014 Share Posted February 18, 2014 ......2 reasons really, firstly you get sucked along.... ^^ thats not really true, Its been tested, and you have to sit within feet of the back of the lorry to have any gain at all. Quote Link to comment Share on other sites More sharing options...
Yostumpy Posted February 18, 2014 Share Posted February 18, 2014 ^^ thats not really true, Its been tested, and you have to sit within feet of the back of the lorry to have any gain at all. how so? why do birds fly in formation? why do cyclists form a peleton? There is a huge void behind a lorry at 56mph, a void , devoid, of moving air, depends what you mean by 'within feet'. All I can say is that it works for me. Where has this been tested? results? read this, called 'drafting semi's' http://ecomodder.com/forum/showthread.php/drafting-semis-19789.html Quote Link to comment Share on other sites More sharing options...
Ex Member Posted February 18, 2014 Share Posted February 18, 2014 Mythbusters did testing. To get any measurable result, you need to be at an unsafe following distance. Quote Link to comment Share on other sites More sharing options...
redneck Posted February 18, 2014 Share Posted February 18, 2014 Check out the Guy Martin Bicycle speed record documentary for some good info on Drafting, some "adults" ran the numbers to establish the best drafting set up Even then, he only had a few feet to play with, certainly couldn't fit a defender in it Quote Link to comment Share on other sites More sharing options...
GBMUD Posted February 19, 2014 Share Posted February 19, 2014 Will check timing, tappets etc when it gets a service. .... ....Boost gauge measuring from the turbo to pump line, at the turbo end. Dave Getting the timing spot on is a good idea to start with, my old 200Tdi used to improve dramatically with a newly set belt. It might be worth checking the boost pressure at the manifold. Currently your FIP and boost gauge are seeing the pressure at the high pressure side of the turbo so the FIP is allowing fuel in in line with apparent requirements. However, if there is a restriction further along the intake system, such as an internally collapsed hose, gummed up intercooler etc., then the turbo will build pressure against this restriction, the FIP, your boost gauge and the waste-gate will see this pressure and react but the pressure downstream of any restriction may be much lower. I would suggest tapping into the inlet manifold (with care and a vacuum cleaner you can remove the swarf through the manifold inlet) and seeing if the boost pressure is there. Potentially, you are allowing extra fuel in without the manifold pressure to burn it properly. Chris Quote Link to comment Share on other sites More sharing options...
C18RCH Posted February 19, 2014 Share Posted February 19, 2014 Mythbusters did testing. To get any measurable result, you need to be at an unsafe following distance. Yes they did but I believe they found even at safe distances there was somthing like 10% reduction in drag. You are correct in that it is upto 80% at about 2ft from the rear bumper. Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted February 19, 2014 Share Posted February 19, 2014 http://mythbustersresults.com/episode80 Quote Link to comment Share on other sites More sharing options...
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