SRDT Posted February 27, 2017 Report Share Posted February 27, 2017 Congrats, the front is higher but at least the rear will adjust itself. Quote Link to comment Share on other sites More sharing options...
Mike T Posted February 27, 2017 Report Share Posted February 27, 2017 Great job! Â Quote Link to comment Share on other sites More sharing options...
Goce Posted February 28, 2017 Author Report Share Posted February 28, 2017 Today i took the mi16x2 now for its first test drive, started by dumping the clutch at 2500 rpm, to shock test the driveline and left two solid tire marks in the garage,it was happy to keep spinning but i lifted off, drove it and was down on power, first thought was a bad fuel injector, pull it in and changed them for the oem ones, and no change, then i transfer it on LPG (propane), the power came back so i might have missed the order on the petrol injectors, never less drove it couple of miles, and the steering needs some work, the bump steer is very bad and i can feel the dropped tie rod ends flexing, the rack it shelf feels nice, well weighted and communicates well, i may say better than the oem one and the brakes are awful, then i took the car to the spot where i took the photos before the conversion for some new photos, i need to fix the steering and the brakes, but for now i plan to have some time off the jack stands and i'm more busy  day by day, before i parked the car in the rear bay of the big garage i cleaned it, you can see the remains of the white line i made before i started the project, and the marks left by the fuel in the exhaust when i first started the engine and was full of fuel form the stuck open fuel injector, the front end came down exactly one centimeter, only 5,5 to get to where it was before. Quote Link to comment Share on other sites More sharing options...
Mike T Posted February 28, 2017 Report Share Posted February 28, 2017 Good progress! Quote Link to comment Share on other sites More sharing options...
Goce Posted March 2, 2017 Author Report Share Posted March 2, 2017 I've been driving it little more now, to be honest i'm falling in love how it drives again. It really reminds me on the first couple of drives when i bought the car, i was afraid not to turn into a tail happy drift car, but it sure wasn't the case. The torsen diff grips extremely well, and it has that solid feeling, not the rubbery feeling of the bmw and mercedes, the pick up of the line is just as i remember it, first lifts the back up then the front end and goes, i still haven't tried high speed cornering but from my experience the balance is much improved, it has no understeer at all, and the back follows the front well, there's a little amount of flex in the chassis but it always has have it. All in all i'm satisfied with the results, not sure if i would recommend that much work to someone else but i would do it again if i have to. Quote Link to comment Share on other sites More sharing options...
Goce Posted April 6, 2017 Author Report Share Posted April 6, 2017 Last night we had rain so i decided even the steering is not fixed to take this car to the spot where i used to drift it, and try to drift it, at first was holding a drift nicely, but as the tires warmed up and the surfaced dried it started to grip hard, it definitely needs more power to overcome the gear ratios, i thought the 405 are light at the back and i can do a little drifting  but i'm pleasantly surprised of how well the chassis is handling the big changes and my abusive driving so i'll have to look else way for drifting, also the hydraulic clutch and short throw shifter are definitely an improvement, sorry no pictures it was dark and wet . Quote Link to comment Share on other sites More sharing options...
Goce Posted April 30, 2017 Author Report Share Posted April 30, 2017 I've had some time and did little more investigation, i thought the engine use to be more powerful but it's been so long since i've driven it hard that i don't remember, but my fuel/air mixture did seem to be all over, so i started changing injectors adjusting fuel pressure no change, then moved to the ignition, put in new bosch spark plugs new coil, and no change, but when i replace the igniter there was obvious change even starting it takes less time, after couple km driven my air/fuel started stabilizing and i can feel the ignition advance as it used to it really comes alive over 4k and pulls harder and harder, but this revealed a new problem, now i'm getting some serious axle hop, on high starts and burnouts, like is a live axle and has broken leaf spring, there was no hopping with less power, has anyone any experience what can be causing this or any fix? Quote Link to comment Share on other sites More sharing options...
Bean Posted April 30, 2017 Report Share Posted April 30, 2017 The (just mine?) 505 will sometimes get wheel tramp with wheelspin on dry pavement as well. Figured it was a by product of soft springs and the semi-trailing rear suspension squatting and rear angle changing. Since it would only do it sometimes I never gave it much thought. In your case - are you actually getting wheel hop?  One or both wheels? Rabin Quote Link to comment Share on other sites More sharing options...
Goce Posted April 30, 2017 Author Report Share Posted April 30, 2017 A Friend watching from side says the wheel is actually jumping inside the wheel well, by the feel both wheels are doing it, the shake it's pretty violent, feels the sunroof will fall on my head. As for the soft springs my car doesn't have any springs in the back, is on hydraulics, did put it on a hoist and check the swing arm bearings, which were replaced only 10.000 km ago, rock solid, did grease them, the anti roll bar looks intact, not sure what else to look at, i'm also looking for good quality rose joint for cheap, to fix the bump steering? Quote Link to comment Share on other sites More sharing options...
Bean Posted April 30, 2017 Report Share Posted April 30, 2017 Is the back lowered at all? Â I'm guessing it's related to the added power going through the rear end - quick google shows the 405x4 to use trailing arms? Rabin Quote Link to comment Share on other sites More sharing options...
Goce Posted April 30, 2017 Author Report Share Posted April 30, 2017 The car is at stock ride height, only the front is 3sm higher now, the diff is held by 3 bushes two in the back on the mustache bar and one in the front, they are ok not great, could be the diff moving and causing the wheel hop? Quote Link to comment Share on other sites More sharing options...
SRDT Posted April 30, 2017 Report Share Posted April 30, 2017 There is a citroën sphere acting as the springs but those won't soften when old ; quite the opposite in fact. On the other hand maybe sending all the power to the rear means spring rate and dampers needs to be looked at. Quote Link to comment Share on other sites More sharing options...
Goce Posted April 30, 2017 Author Report Share Posted April 30, 2017 The sphere has been replaced just before i took this car of the road, over the years i've used harder 55 bar sphere even 62 bar which made it rock hard, now a have the standard 40 bar sphere on it, as for the valveing, i think something else at play for the wheel hop, and i'm starting to wonder how much power is it producing now. Quote Link to comment Share on other sites More sharing options...
Bean Posted May 1, 2017 Report Share Posted May 1, 2017 I think you may need to set up a camera / phone under the car while you record a burn out to see what's happening. My guess is the trailing arm design used on the 405 isn't located well enough for RWD only...  Even on my 505 a good friend of mine suggested I lower the rear cross member so that the trailing arm wasn't angled up to the mount so much and was horizontal. The 405 trailing arm doesn't look like it's as beefy as the 505 set up, so curious if they're just moving around too much. Rabin Quote Link to comment Share on other sites More sharing options...
Goce Posted May 1, 2017 Author Report Share Posted May 1, 2017 All of yours suggestions made me want to troubleshoot this even further, so i called a friend got her to drop the clutch at 5k whale i was watching from the back, we did this couple of times, and found that first to vibrate is the drive shaft, than the exhaust and then the diff and mustache bar, after all that then the tires start to skip, but in the meanwhile the diff is bouncing like a pendulum, after i drop my friend off pull the car in the garage and hummer in couple of plastic wedges in those bushings, drivers side has a split and knowing i'll have to replace them taught should try, so with the wedges if i preload the drive shaft the cars leave like a missile very little vibration until the tires grip up and go's, this lasted maybe 5-6 times and the the hop return, when i got back home looked under and took those photos, the wages were gone, only small piece mushroomed was left, it seams the forces are quite big, also managed to measure the angle of the trailing arms, is between 10 and 12 degrees, now i need to figure out what to use in those bushings, even with the wages in there there was lots of vibrations and noise, which i hate, any thoughts? Quote Link to comment Share on other sites More sharing options...
Mike T Posted May 1, 2017 Report Share Posted May 1, 2017 Wow the diff is so low! Quote Link to comment Share on other sites More sharing options...
SRDT Posted May 1, 2017 Report Share Posted May 1, 2017 Yes but with the hydraulic self leveling suspension it won't go any lower than that. Quote Link to comment Share on other sites More sharing options...
Bean Posted May 1, 2017 Report Share Posted May 1, 2017 Delrin bushings would remove any movement, but they would also transmit a lot NVH to the unibody which would suck. Agree with Mike on how low that diff is mounted - on the 505 the top of the diff is very close to the boot floor.  My first thought was if the moustashe bar was upside down!  New bushings would help, but I wonder if there is any added reinforcement that could be done to stiffen up that diff mounting while still being rubber isolated? Rabin Quote Link to comment Share on other sites More sharing options...
Bean Posted May 1, 2017 Report Share Posted May 1, 2017 Knowing nothing about the rear suspension I found this you tube of a guy rebuilding the rear end... https://youtu.be/hNRnSEA46zg WAY more complex than I would have imagined. Â Very cool. After seeing more about the rear suspension I'd just focus on the bushings supporting the diff. Â In the video he made his own polyurethane bushings which might be a good option since you could use a softer durometer urethane so it doesn't transmit too much NVH (Noise Vibration and Harshness) on the moustache bar, then maybe a machined Delrin bushing on the pinion bracked on the nose of the diff. Rabin Quote Link to comment Share on other sites More sharing options...
Goce Posted May 1, 2017 Author Report Share Posted May 1, 2017 The diff is mounted like that so the axles are straight on ride height, and the fuel tank is lower then the diff by couple of centimeters, SRDT is right with the hydraulics it never goes lower than this, no matter the load, the car looks higher on pictures probably, but on the lowest point at the fuel tank is only 7,5sm from the ground, but has no scraping issues, roads here are not the best, steep driveway high sidewalks never scraps, you can see on page 10 when i was washing it how steep my driveway is, that is not a problem, i'm not sure if i can found polyurethane here to make my own bushings, white plastics like teflon, nylon, delrin are available and i can turn one on my lathe in minutes, about the complexity, those cars were ahead of their times, and the ride they provide is superior to FWD 405, this is the main reason why i've been thru all this to save it and enjoy it. Quote Link to comment Share on other sites More sharing options...
Bean Posted May 1, 2017 Report Share Posted May 1, 2017 I wonder if the moustashe bar itself may be flexing too much with all the power now going through only the rear diff... Is there much room to reinforce the plate? Rabin Quote Link to comment Share on other sites More sharing options...
Goce Posted May 1, 2017 Author Report Share Posted May 1, 2017 The mustache bar is made from spring steel, one of the first jobs i did is to strengthen couple of spots back at the start of my build thread, its made to flex only back and forward but is stiff left to right, to resist twisting under load, and how accurate are smartphone dynamometers, i did a pull and the app showed 155kw crank on gasoline and 144 kw on LPG, and feels faster then ever with the long gearing it starts to move around (wheel spin) near redline, is this right, things done to the engine are reground camshafts, aftermarket fuel regulator, redesigned intake manifold, much bigger throttle body, cone filter, good flowing exhaust, remap ECU with a very agressive ignition map even with all of that 155 kw seam high? Quote Link to comment Share on other sites More sharing options...
Mike T Posted May 2, 2017 Report Share Posted May 2, 2017 I would have thought that a good "whoop de doo" bump would put that diff right onto the ground.  I know Peugeot put this suspension in the back to keep the diff up but a major compression on the road won't stop it from getting dangerously low.  I wonder if many X4 s actually had this problem.  My 404 has nearly 15 cm of clearance under its diff, which seems quite low due to the worm drive, but it's a live axle so it never gets closer to the road. Quote Link to comment Share on other sites More sharing options...
Goce Posted June 11, 2017 Author Report Share Posted June 11, 2017 No "whoop de doo" has ever put the diff in the ground, i've been accidentally airborne with this car and landed flat without even a scrape, the WRX behind me at the time broke a front control arm and crashed, that thing made a light show of sparks, lately i've been busy and have been waiting on heim joints, to be able to fix the steering the right way, but i've order left hand threads joints, forgetting i'm running a rack not a steering box, and now i have to buy a M12 left threading tap, or order a right tread heim joints, wich i may do, bigger should last longer and if i can put a rubber boot on them to look like OEM rod end. Quote Link to comment Share on other sites More sharing options...
SRDT Posted June 11, 2017 Report Share Posted June 11, 2017 If you need a M12 left threaded nut you can tap a regular M10 one, I have seen that on stainless turnbuckles. Quote Link to comment Share on other sites More sharing options...
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