Thread: Test fitted a prototype set of B13 coilovers

I spent the day building a set of B13 coilovers. I have always ran progress coilovers on my B13 and love them. However, for my 4-door currently in the works which will only be a street car I wanted something that could go much lower than the progress coilovers. Then I decided why not make a coilover that will out perform my progress coilovers when at proper ride height, but allow me the option of dumping the car if i want for aesthetic purposes.
So after taking apart the Progress units and testing them on our Roehrig shock dyno we learned that they are a very good damper. They out perform koni, stance, ksport, bc racing, and a few other brands by a long shot. To out perform the Progress units I needed something special so I went with a Fortune auto 500 series digressive monotube damper that is 30 way adjustable and has a huge 57mm piston. These dampers dyno better than than anything else in the price range so they are the heart of my new coilovers.
I got the prototypes mounted up tonight and the fit is perfect using my ground control plates in the front and progress top hats in the rear. Fortune will be making the front pillowball camber plates for this setup and i will use those so I can keep the gc plates on my track car. also making aluminum rear top hats with urethane bushings for the rear. btw im running higher spring rates too, My progress springs are 350/250lb the new setup is about 450/335lb.
This is a one off setup and is not a production application but if you guys are interested they have agreed to reproduce this at a special group by price for 10 or more buyers. But we will cross that bridge later if enough people contact me interested. And no I do not work for fortune auto they are just located in my home town and i have had lots of experience with their products. I'm sure the owner would consider becoming a vendor and offering b13/14/15 coilovers if the demand was high enough, they stock s chassis currently too.







here is a dyno of the 500 damper they also have a new 510 damper that is even better but overkill for my purposes.

Is the rebound the positive or negative number?

They make P10 coilovers, also.

looks good.

you know paragraphs help the reader a lot...

you ninja edited your post. rebound is the bottom plot. the sharp drop and rise represents slow input such as precise car control and the long slope is high speed(like sharp bumps and such)
This is an excellent street damper, thats why I chose it. It actually has much more favorable rebound characteristics than Progress or any other damper under about $1500 dollars. Ill post the progress dyno graph tomorrow for a visual comparison.



Yeah sorry, when ever I try writing about a project it turns into a big jumbled run-on... Ill edit it later.

very cool.

For the third time, when someone want to go really low (for whatever reason), I am thoroughly impressed at the initial post. You just joined Mike K and Russel in that regard. Congrats, rare company indeed.

Are those Progress spring rates the standard spring rates that came with the Progress B13 set-up? Or did you change them out?

Why the higher spring rate than you utilized with your Progress set-up?

How do you predict the ride comfort will be with this new coilover set-up and the higher rate springs? Equal to, better, worse than the Progress set-up?

Better than any other damper under $1,500.00 leaves my mind spinning on the cost of the entire set. Is that number for all four (4) dampers? It must be if you are talking comparable price-range to the Progress suspension.

I am very interested in additional information, facts and details.

I have been hoping fortune auto would make coilovers for the b13. They have a excellent product. The spring rates are identical to what the tein ss coilovers use. I would be interested in a set depending on the price.

Fortune Auto 500 Series Coilovers - Fortune Auto USA

Fortune has been making coilovers for over twenty years. They were the first manufacturer to produce a digressive coilover system for under a grand.

The progress spring rates are what they offer for their b13 application. they will put higher spring rates if you request. And I say again they are extraordinary coilovers and I was surprised how well they dynoed.

the reason I'm going higher spring rates is so I can be really low and have flush wheel fitment with less sag from passenger weight and less rubbing over bumps. If they were to produce this you could go with whatever spring rate you want. Its just MY reason for building these is so I can go low on my beater for aesthetics. The shock body on these can be lowered independently from the spring perch so you don't have to lower preload as you lower the car like you do on a Progress style solid body.

When I say under $1500 I'm saying all 4 with front camber plates shipped to your door. So far the best thing in that range made for the b13 is progress and they do not come with front camber plates or even top hats period. you have to buy some $300+ ground control plates or some other brand.

I have always personally felt that progress at the proper ride height rides very well on the street for a coilover. So I'm hoping for about equal ride comfort even at a higher spring rate due to the massive digressive piston utilized in the fortune damper. its simple rule of physics that when you dump a car way too low for the sake of looks, especially with the geometry of a b13, its not optimal for ride quality or handling. The progress coilover basically wont let you go low enough to where you are too low for optimal handling. the term is "low and slow" for a reason.

I'm friends with the owner of fortune but am also being as unbiased as possible and have dynoed all these different brands myself on a roehrig shock dyno. Because we are friends he is helping me get this set made for my car. He doesn't know anything about the sentra community and does not think there is a big market, even though I'm trying to convince him otherwise so if you guys like this idea feel free to call and ask about a b13 application or pm me and ill show him my pms. I would love to see this as an option for the community, because right now there are not many available.

Final assembly in the USA... has my vote. I've heard nothing bad about these, and would definately like a setup