mossy74 Posted April 22, 2008 Share Posted April 22, 2008 I've got a 1970 240z with a 327 chev and I plan on putting on some aluminium heads to save some more weight on the front, so I'm guessing that would make it similar to the weight of the L series engine. I've got some tokico illuminas on the way but I'm unsure about which coilover and spring rate to get, I was going to get the ground control kit but they don't list the spring rates. Quote Link to comment Share on other sites More sharing options...
Dan Juday Posted April 22, 2008 Share Posted April 22, 2008 I've had a couple people ask me about spring rates recently specificly in regards to coilovers (why they ask me is a mystery as I'm no expert on suspension tuning). If you search and do a lot of reading you will find many different answers based on several factors but mainly how you plan to use the car. It might be nice if the real suspension experts here posted a sticky that would compile some of the general guidelines and at least give ranges of recommended spring rates. Then a "non-expert" (like me and a lot of others) could get a general idea based on his particular set of parameters of at least a starting point for choosing spring rates. What do you think guys? Does this idea come too perilously close to "spoon feeding"? Quote Link to comment Share on other sites More sharing options...
jeffz Posted April 22, 2008 Share Posted April 22, 2008 Yea, what is your intended use. Street rates will be different from track rates. Quote Link to comment Share on other sites More sharing options...
mossy74 Posted April 22, 2008 Author Share Posted April 22, 2008 Mostly spirited sunday driving, it may see the track every once in a while but not that much, I'll probably get another mx5 down the road and use that as my track beast. I guess the main thing that worries me is will the stardard rates from the GC coilovers be fine. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted April 22, 2008 Share Posted April 22, 2008 I tried to do that with this post Dan: http://forums.hybridz.org/showthread.php?t=114631 The bottom line is that there is no "right" answer and I'm sure Ground Control doesn't have spring rates listed because they don't have a set rate. You call them up and they'll send you what you prefer. Tokico says that the Illuminas top out at around 275 in/lbs. Any more than that and the spring rate will be more than the shocks can cope with. I ran 200/250 front and rear with sway bars and that worked fine for me, but I had the L6. If you have the aluminum heads and intake, you should be fairly close in weight so something like 200/250 or 225/250 should be fine. It will ride fairly smooth on the street if you turn the shocks down to 1 or 2. If you turn them up to 4 or 5 it will be very uncomfortable (in my opinion) for street driving. Quote Link to comment Share on other sites More sharing options...
jeffz Posted April 22, 2008 Share Posted April 22, 2008 I am at the upper end of the spring rate for these shocks. I have 250/275 front and rear. That is way to stiff for street use. I'd recommend giving them a call (if nothing here gives you the answer you were looking for), they are very helpful and I am sure would be able to get you in the right direction. Jeff Quote Link to comment Share on other sites More sharing options...
mossy74 Posted April 23, 2008 Author Share Posted April 23, 2008 The place I was goping to buy the GC coilovers from says the spring rates for the illuminas are 425/250, does that sound right to you guys? Quote Link to comment Share on other sites More sharing options...
jt1 Posted April 24, 2008 Share Posted April 24, 2008 No. Spring rates are somewhat subjective as to how stiff you can tolerate on the street. I've got 250F/275R like Jeff, and with the shocks set to 5 you don't want to ride around in it for long. With them backed off to about 2, it's better but still quite firm. When my Z becomes a street car again, I will use something like 175F/200R, or maybe 150F/175R, with the Illuminas. Do you know anyone with a modded Z? Bum a ride, see how their car feels, and ask questions. jt Quote Link to comment Share on other sites More sharing options...
Dan Juday Posted April 24, 2008 Share Posted April 24, 2008 Just FYI, I have a 305 tpi with iron heads and a T5. I have GC coil overs with Eibech springs 150f/200r with Illumina 5 ways set to 1. My car is strickly street driven. I would rate the ride as better than my wife's stock '06 Mazda 3. Quote Link to comment Share on other sites More sharing options...
jeffz Posted April 24, 2008 Share Posted April 24, 2008 The place I was goping to buy the GC coilovers from says the spring rates for the illuminas are 425/250, does that sound right to you guys? No. 425 is way over the top. IMO, 250 is too much for street driving also. Dan and Jt1 have some good recommendations. And probably closer to the range you would want to be in. Jeff Quote Link to comment Share on other sites More sharing options...
mossy74 Posted April 24, 2008 Author Share Posted April 24, 2008 Thanks for the info, I think I'll go for 200f and 225r. Also I bought the 240z illuminas but I see that some of you guys are using mr2 fronts, will my ones work okay with sectioned struts? Quote Link to comment Share on other sites More sharing options...
jtmny1999 Posted April 24, 2008 Share Posted April 24, 2008 Thanks for the info, I think I'll go for 200f and 225r. Also I bought the 240z illuminas but I see that some of you guys are using mr2 fronts, will my ones work okay with sectioned struts? To section the tubes you need front socks to go in the back. and mr2 shocks in the front. -JT edit: BZ3099 is what I used in the front. That is a rear 88 MR2 strut. Then I used the 240 front strut in the back, but I don't have the number for that one. . Quote Link to comment Share on other sites More sharing options...
mossy74 Posted April 25, 2008 Author Share Posted April 25, 2008 Hmm, maybe I got the wrong shocks, I guess the other question is do I really need to section the struts. The 240 is in resto stage at the moment but I'm running the SBC with zg flares and 16x9 and 16x9.5 watanabes. From what I've read if you use camber plates that drops the height about 1.5 inches straight away, I'm still new to all this mechanical side of things and it gets pretty confusing. Quote Link to comment Share on other sites More sharing options...
Dan Juday Posted April 25, 2008 Share Posted April 25, 2008 Sectioning is not required. And yes, camber plates replace the rubber isolaters so this alone lowers to car about 2" (50mm). Since you already have the strut carts I'd recommend you continue with unsectioned struts. If you decide later to go lower you only have to buy two new strut carts. All the other parts can be re-used and you can sell your old Tokicos to another Z mate. Quote Link to comment Share on other sites More sharing options...
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