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Old 04-29-2016, 02:01 PM   #1
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Default AST 5100 or Xida Gen 2

Greetings everyone!

I have come to a fork in the road on which setup I should purchase, and would like your opinions. A friend of mine is selling his brand new AST 5100 for a good price, and there's a set of used Xida Gen 2 up in the classifieds.

XIda Gen 2
  • Used - has seen track days (~4k miles)
  • 700 / 450 spring rates
  • Double Digressive Piston
  • NB top hats
  • ~$1800 shipped
  • Rebuilds by HVT in Texas (???)
AST 5100
  • Brand New
  • 12kg/7kg spring rates (~672 / ~392) Swift springs. Can change out spring rates to whatever I want for no additional charge.
  • Standard piston
  • Whatever AST supplies for their top hats
  • ~$1900 local
  • Rebuilds by HVT in Texas (???)
I have no doubt with either setup the performance would be a lot better than my current setup (valved Bilstein and GC setup 700/400), but I feel like I would miss out once ACE is released for the Gen 2. Not to mention, I believe Xida has great resale value compared to the AST. I'm kinda leaning towards the Xida...

The Gen 1 Xida are tweaked 5100?



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Old 04-29-2016, 02:17 PM   #2
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Gen1 XIDAs are 5100s valved and built to 949's specs. Gen2s are Tractive shocks built to their specs. The Gen2 valving is better because the Tractive shock's internals allows for a more digressive rebound curve. There's no comparison - the Gen2 XIDAs are better.
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Old 04-29-2016, 02:45 PM   #3
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So in theory, the AST 5100 would be comparable to the Gen 1 Xida (kinda). Also is there any way to determine if the xidas are gen 1 or gen 2?
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Old 04-29-2016, 02:57 PM   #4
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Quote:
Originally Posted by .one lane View Post
So in theory, the AST 5100 would be comparable to the Gen 1 Xida (kinda).
Not really.

Quote:
Originally Posted by .one lane View Post
Also is there any way to determine if the xidas are gen 1 or gen 2?
I'm like 75% sure that gen1's had a black spring perch and gen2's had an orange spring perch, but that isn't 100% guaranteed.

I do know that gen1's had a vent washer thingy on the shaft that the gen2's do not have.

And yes, both can be rebuilt in Texas. Not sure its HVT anymore. I think its a spinoff of HVT. http://www.inertialaboratory.com/
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Old 04-29-2016, 04:04 PM   #5
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Quote:
949racing SuperMiata Xida Gen 2 with NB top hats [$2500] - $1800
(Installed Dec 2015 and have ran three events. Under 4k miles.
Spring Rates 700 in/lbs Fronts, 450 in/lbs Rears With the Dual Springs system. This is the first version of the Gen 2 before they revised the poduct and changed manufacturers to cut cost.)
The seller infers that he has a superior product when Emilio had the xida's built by AST but like Savington commented that is not the case. Personally i would spend 200 more dollars and buy them direct from 949.

Edit: They are gen 2 purchased before the price cut.
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Old 04-29-2016, 04:28 PM   #6
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Quote:
Originally Posted by BMWidmer View Post
. Personally i would spend 200 more dollars and buy them direct from 949.
Sells tax prevented me from buying new from 949. Finding a used set saved me $200 in tax on top of the discounted price for being used.
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Old 04-29-2016, 04:41 PM   #7
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I don't know if .one lane reside's in California but 400 dollars more then the asking price of a used set isn't that substantial to have brand new suspension.
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Old 04-29-2016, 07:33 PM   #8
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Depending on the bodies used the AST 5100's could have less travel than Gen 1 XIDA's. That was one of the factors beside valving. Gen 2 AST hats helped address that.

I would not suggest the used 949 ones. Way to many unknowns. Premature rebuild costs would eliminate any savings over new and likely end up costing you more. If money is tight just wait until you can afford new.

Last edited by k24madness; 04-30-2016 at 01:35 PM.
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Old 04-30-2016, 05:19 PM   #9
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There are several sets of non-Xida AST 5100's floating around build by Vorshlag, which became AST-USA with a new owner which became HVT with the same owner. They don't share the dimensions or valving of the Xida. Of those non-Xida 5100's, they vary in spec so there is no one comparison. There were some early prototypes and shocks made with leftover components. They could be really close to Gen 1 Xidas are miles apart. AST-USA, now with yet another owner still produce my Gen 1 design built to order for $1899 w/o mounts, but not marketed as Xida as we own that trademark. Website states with mounts but that isn't the case. Your guess is as good as mine WRT to the old non-Xida functional comparison but probably not worth the risk if you are spending more than $1000. Gen 2's are $1699 for the base kit without mounts and in stock.

So it's clear, the change to Tractive was because AST USA could not grow with us. With Tractive we got a better shock, bypassed the US distributor to cut their margin out, passed those savings onto the customer and never looked back. We sell, many Xida kits, which also serves to bring the price down.
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Old 04-30-2016, 06:39 PM   #10
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1800 for used XIDAs would have been good, but 949 recently did a price drop on them. I think my NEW set was 2000 shipped or so, WITH top hats
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