Metako Posted November 20, 2006 Report Share Posted November 20, 2006 I'll be ordering some custom 38mm (1.5 inches) lower front springs for the SR20-505 soon and I am interested in opinions as to the ideal spring rate to specify. Being origionally a GR the origional springs are extremely soft (about 65lb/inch I think) so if I go to 30% harder I will get the std 505 turbo spring rate (86lb/inch). Is this the best rate to use or should I go 30% over the std turbo rate and specify 112lb/inch? What do people think? You have been driving your cars alot longer than I have mine so I would value your opinions. I currently have a 58mm gap from the top of the tyre to the guard lip and I want something like a 20mm gap. The rear springs are already stiffer than std but I will probably get lower ones there eventually too. Quote Link to comment Share on other sites More sharing options...
august Posted November 20, 2006 Report Share Posted November 20, 2006 if your not going to take the car to the track, I'd stick with the stock 505 front springs. What is the weight difference between the SR20 and N9TEx? cutting one coil off the stock turbo front springs lowers the car the perfect amount if you ask me. if you go with something that lowerrs the car 1.5 inches, and is stiffer, i think the front of the car will be underdampened. even cutting one coil off the front springs, with NEW oem struts is borderline too soft on the damping side of things. the combo of new oe springs + struts with stock springs is really really good if you ask me, it sucks to change that unless you could find the same ratio of damping with your custom springs let us know what you find out / get made. i'm curious to hear what you end up with. Quote Link to comment Share on other sites More sharing options...
Metako Posted November 21, 2006 Author Report Share Posted November 21, 2006 So if a damper could be found/made with heavier damping to match the springs would you go any heavier with the spring? Sounds like you like the stock springs although if you cut off one coil then you'd be increasing the rate a bit too. I tried cutting coils once before on another car and they were noisey and rattley, and I'd also hit the bump stops alot too so I dont think I'd do this again, hence getting new shorter ones made. Also I forgot to mention that the new springs will be the progressive type. By the way, what sort of gap do you have between the top of the tyre and the guard lip with one coil cut? As for the dampers-I might try experimenting with using a slightly heavier motorcycle fork oil. Or, I've heard that Boge Turbo Gas dampers are quite heavy-anyone have any experience of these? Quote Link to comment Share on other sites More sharing options...
V-M Posted November 21, 2006 Report Share Posted November 21, 2006 As for the dampers-I might try experimenting with using a slightly heavier motorcycle fork oil. Or, I've heard that Boge Turbo Gas dampers are quite heavy-anyone have any experience of these? Originel ones with new parts (piston "ring" and upper cover) and suitable fork oil (temperature selected) will be the best result (if not using daily race). I'll comment those springs when I'll install those Volvo 200 series ones in front. With modified original shocks -> I changed also down direction valves with stiffer spings (those small ones). In my opinion only Bilstein insertion struts could be nearly as good as originals with small modifications. Other ones are not good at all, surely those felt good as start (cause usually earlier ones are totally in end of life). V-M Quote Link to comment Share on other sites More sharing options...
august Posted November 22, 2006 Report Share Posted November 22, 2006 V-M i'm curious to see how you like the Volvo springs. When the time comes, i think i might try those as well.. as far as the damping goes. i bought new OEM struts, and cut the springs all at once. it did of course feel lighter on the damping side of things, but its definitely underdampened. however I do like the feel of the stiffer damping of the 505.. aah decisions decisions. In a perfect world, i would love to chang the oil to find something thicker. i honestly haven't taken any inserts apart though, and haven't looked into how i'd go about the whole process. as far as drawbacks from cutting the springs, the stock springs are so damn hard i think it's a OK thing to do. there is no creeking or rattling, it's just lower in the front. actually, i got the idea from someone who used to race 505's in the 80's. he said what he does to the 505's he's still racing today (in stock trim) is cut 1-1.5 coils off the front springs, which gives the car the perfect increase in spring rate and camber increase for racing (he didn't say anything about damping, but i didn't ask either). in any case, if you do go forward with progressive custom springs for the 505 it'd be great. i really wouldn't go too much stiffer then stock (if at all) for your first batch. let us know how it goes, and how much you pay. i'm sure there are some people out there who'd love to try em out you've seen this right? http://www.505turbo.com/forum/index.php?showtopic=59 Quote Link to comment Share on other sites More sharing options...
august Posted November 22, 2006 Report Share Posted November 22, 2006 speaking of which, this is kind of a bad angle, but will give you an idea what 1 coil of the stock springs will look like. (i can take actual measurements if you want) Quote Link to comment Share on other sites More sharing options...
Metako Posted November 22, 2006 Author Report Share Posted November 22, 2006 Your car looks very nice August. Measurements would be appreciated. By the way my car weighs 1300 exactly now so very similar to std 505 (has aircon and power steering). Your friend raced 505s with 1-1.5 coils cut! Mmm will try to work out what the spring rate of this would be (have a formula somewhere). As I have GR soft springs now I would have to buy a pair of GTi/Turbo springs (about $80 pr here) and then cut them, so I figure I would rather pay $170 pr custom progressive rate and get exactly what I want. The reason mine rattled after cutting was when you cut the spring it doesnt sit square anymore and this caused it to rub against something and also the strut didnt capture the shorter spring properly. So if I work out the rate of the std turbo spring with 1-1.5 less coils, and make them in the length I want, sounds like I should get a pretty good spring. The springs you are refering to - are they the "D" + "E" combination from the table? And how many "active" coils do your springs have? Quote Link to comment Share on other sites More sharing options...
august Posted November 22, 2006 Report Share Posted November 22, 2006 I honestly don't know what springs I have. They are just the OEM springs from an N9TEA (manual with AC). i havent personally seen the spring setup Arlo runs, or if 1.5 coils would even work with the mounting, but that's what he said. Quote Link to comment Share on other sites More sharing options...
Metako Posted November 23, 2006 Author Report Share Posted November 23, 2006 Thats OK. As its a USA model I will assume its D and E. Will get back when I have worked out the spring rate. Quote Link to comment Share on other sites More sharing options...
Metako Posted November 23, 2006 Author Report Share Posted November 23, 2006 I worked out that if turbo spring "E" has rate of 87.52 lb" (from Aussiefrogs source) and a thickness of 14mm then it must have 7.4 coils. If we chop 1.5 coils off this that leaves 5.9 coils which gives a new rate of 110.28 lb" which is very close to 130% of the std rate (113.17 lb"). I think I have my new spring rate. Quote Link to comment Share on other sites More sharing options...
august Posted November 23, 2006 Report Share Posted November 23, 2006 I worked out that if turbo spring "E" has rate of 87.52 lb" (from Aussiefrogs source) and a thickness of 14mm then it must have 7.4 coils. If we chop 1.5 coils off this that leaves 5.9 coils which gives a new rate of 110.28 lb" which is very close to 130% of the std rate (113.17 lb"). I think I have my new spring rate. wow, nicely done! i really wish dahlems would have given up the specs to their progressive 505 lowering springs (just to compare) you know, hmmmm. I think Jim Lill bought some of these 505 springs from Dahelms a few years ago, but didn't use them. I think he was trying to sell them when he left the peugeot group. If your a member of the Peugeot-L mailing list, it might be worth it to *try* track them down. even if the new owner would just let us 'borrow' them for measurements Quote Link to comment Share on other sites More sharing options...
Bean Posted November 25, 2006 Report Share Posted November 25, 2006 I think Mike Murphy may have got the Dalhems when he bought Jim's project car - not sure as he may have sold them separately... Good work on the spring rates too Metako - I've been meaning to do that as well (figure spring ratesafter cutting coils). Amsoil makes some really good motorbike shock oil for use in Motorbike shocks - I used it in the rally car's struts (Bilstein) and it worked awesome. Comes in two wieghts - so if you decide to up the spring rate I'd suggest you use a heavier shock oil to increase the damping rates as well. One of the reasons behind Peugeot's ride quality is that they are softly sprung and stiffly damped... Rabin Quote Link to comment Share on other sites More sharing options...
Metako Posted November 25, 2006 Author Report Share Posted November 25, 2006 Rabin, can you remember the weight of fork oil you used? Was it 20wt? I believe you can get 5wt to 30wt fork oil and the std weight used in forks is 10wt. Good to hear that heavier oil works! Also I'm trying to think of a way to identify if I have the factory Peugeot struts or aftermarket inserts without taking them apart. Any ideas? Quote Link to comment Share on other sites More sharing options...
Bean Posted November 30, 2006 Report Share Posted November 30, 2006 Sorry for the delayed response... I could only find two different rates here for AMSOIL, and I have both weight's in my garage - so I'll check tonight. The Bilstein's were DONE - so I used the thicker shock oil, then put a seal spring (the circular on behind the sealing lip) from a smaller seal into the shaft seal. Struts lasted for 6 more rallies without a refill - and the car handled even better than it had when we first got it. As for the inserts - I've heard that inserts are exactly that - a sealed inserted tube. OEM used the strut housing itself - so if there's a sleeve in there it's an insert. Not sure how the OEM inserts rate - but i heard you're better off to just get the seals for the housings and reuse them with new fluid - which is what I have waiting. Rabin Quote Link to comment Share on other sites More sharing options...
Metako Posted December 1, 2006 Author Report Share Posted December 1, 2006 I might remove one of the springs from my car before I place the order just so I can measure the free height, nr of coils etc and take a pic for the makers of the new spring, as I really dont know if I have std springs in there or not. When I do this I will have a look to see if I have inserts or origional struts and get some W20 shock oil and a new seals for the struts. Thanks for the feedback. Quote Link to comment Share on other sites More sharing options...
Johnny Posted January 1, 2007 Report Share Posted January 1, 2007 Do you realise that you need to order springs that are not just 38mm shorter (free length) than those you have now? Quote Link to comment Share on other sites More sharing options...
Metako Posted January 1, 2007 Author Report Share Posted January 1, 2007 Yes, but the manufacturer here wants to know how much lower do I want the car to be and then they do the calculations. Quote Link to comment Share on other sites More sharing options...
Johnny Posted January 2, 2007 Report Share Posted January 2, 2007 Ok, great! Quote Link to comment Share on other sites More sharing options...
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