More info on Penske shocks

[fooddude]

How much are JRZ's for the frs/brz btw?? ...and for each level/trim/adjustability?

[solidONE]

Originally Posted by mike the snake

When I had my Porsche race car, I used "Smart Strings", basically strings to do the aligment. 90 degree plates on the ground, against the wheels for camber, and string and a tape measure for toe.

I thought SmartStrings were for toe measurements? I was thinking there are many alignment "systems" out there for sale south of $500 and the rest of the imaginary money can go toward building ramps and leveled pedestals that will allow easy access to the underside of the car with the wheels still on the car and fully weighed on a level surface. That or it could go toward pouring a slab of perfectly leveled concrete to take measurements on. And throw in another thou for hookers and blow. Ah... gotta love that imaginary money... lol

Originally Posted by cdrazic93

At what cost though? 10k for the Penske, and sure you have all these options but if you're not tracking the car at all, then no need to spend that kind of cash for something that's attainable on the street for half the price with the JRZ. Even so these Penske dampers are the race series. So applicable only to the JRZ raceline the 12 31 and 14 31.

Either off the shelf preset or custom spec'd. Agreed no one has the customization that Penske does, but 95% of those looking for really nice suspension won't know what to do with that level of customization.

Edit: if I knew all the things that went into a damper to change it's characteristics you bet I would go all out for some nice Penskes. But there's two problems with that;

1. I don't know a quarter of the options I'd be looking at and what a change any of them would do
2. I haven't had enough suspension experience to know the ride difference between a well setup Penske and a well setup JRZ.

I thought we were playing with imaginary suspension budget here? Well... if you put it that way, why even spend that $5k on the JRZ RS? I doubt you will tell much of a difference between some of the $3k offerings in the KW clubsport or Ohlins road and track if that was the case. Still less than 5K are the AST 4150's, or MCS 2-way non remotes that are both monotubes and likely cheaper than the JRZs?

[solidONE]

Originally Posted by dwx

Yeah the guys I know who use them and know what to do with them swear by them completely. You can also go find just about any circle track shop/builder and they are also using Penske shocks and can supply parts or even work on them for you.

They are also a lot more durable than you might think. I know people who daily drive on 8300 setups and never have any problems, just because they are expensive doesn't mean they wear out quickly. They use good parts, good seals, and they are engineered well.

I've been beating on a Penske 8760 on road and track (mainly on the streets and mountains) for the past 3+ years without rebuild on my bike. Overdue for a rebuild, I know, but it works just as well as when I bought it. Just had to jack up the damping a couple of clicks, still hanging in there nicely.

[CSG David]

Originally Posted by dwx

I did last year for autox since I was in stock class and I still am, only because I haven't had time to swap springs.

Lol. You're going to need those spring perches so you can use "race springs" instead of the OEM style setup.

[dradernh]

Originally Posted by DougW

...now for the street Damptronics

Now = ?

[cdrazic93]

Originally Posted by solidONE

I thought we were playing with imaginary suspension budget here? Well... if you put it that way, why even spend that $5k on the JRZ RS? I doubt you will tell much of a difference between some of the $3k offerings in the KW clubsport or Ohlins road and track if that was the case. Still less than 5K are the AST 4150's, or MCS 2-way non remotes that are both monotubes and likely cheaper than the JRZs?

Well if we're playing with unlimited money then yes Penske 4 way with all the frosting on top.

I was alluding to the fact that (it's my fault) for the lack of experience to know the difference between the JRZ and Penske

[DougW]

Originally Posted by dradernh

Now = ?

Got to get through some back surgery again after Road Atl, still smiling though. I'm trying to work out the rear top mounts the bearings are just to clunky for street so it's got to have a soft poly bushing but the body hole is just 1" so it's not an off the shelf part. I could supply shocks and hardware now if someone wants to develop the rest. Now back to Penske I think ever other shock manufacture is just a copy of Penske's last mistake they understand the science of control.
DougW

[xwd]

Originally Posted by CSG David

Lol. You're going to need those spring perches so you can use "race springs" instead of the OEM style setup.

They come with regular lower perches as well...

[Captain Snooze]

I was looking at some porn I mean looking at the Penske website and for some reason was unable to find the BRZ page. The link from the OP returned "This product is unavailable or temporary disabled."
Mmmmm... I wonder what's going on there? Doesn't really matter as I haven't won the lottery.

[RBbugBITme]

Hello,

I am the designer of the BRZ shocks and I develop all of the product pages for the website so I am as they say, the horse’s mouth. There is some misinformation here I would love to clear up and I’ll answer any questions you have. Our willingness to get involved in forums like this is part of what we call the Penske Advantage. You can also call us anytime, all of the design work and most of the builds are done in the Reading, PA office.

First, the picture of the shocks that are on the early pages of this thread was taken by me prior to shipping our first developmental set to the customer, a well known west coast shop who shall remain nameless for now and will eventually become a supplier. They are doing things a little differently than we normally would and they have developed their own rear upper mounts to maximize stroke while lowering the car a lot. I got off the phone yesterday with them and they said they just won 2 of the SCCA classes they entered last weekend but they’re 1” higher than anyone else and want to go lower. I do what the customer wants so this package is still in development.

With that, I decided to take down the product page because we cannot confirm at this point whether our package will bolt onto an otherwise stock BRZ and have the necessary ride height range and stroke. We’ll work on that once we’re done with this customer/supplier.

The package: These are body up (the only in existence?) rear monotube shocks and inverted monotube front struts. Packaging has been difficult because they are inline monotubes, there is no external reservoir to save cost, and he wants them as short as possible to lower the car. The front and rears are also dual-bleed as of right now, something no other competitor can compete with in terms of low speed adjustability range and in what the driver can actually feel. One misconception out there is that if the damper curves match between competitors’ shocks, the car will feel the same. It simply isn’t so.

What do they cost and what do you get? The above described set will be in the ballpark of $7,700. That includes everything pictured. You’ll have to get the rear upper mounts from our customer’s shop to run this exact setup. Springs are separate also so you can get whatever mfg., length, and rate you want.

Why is it so expensive? The set described above is fairly high end due to the dual-bleed adjusters but the main driver, and the reason for the large jump from the Corvettes, GT40’s, etc., is the front struts. Those cars all have shocks at all 4 corners. Inverted monotube struts are very expensive when done correctly because of the amount of material and machining involved. Did you notice the machined aluminum clevis from billet 7075? The reason Anze is a less expensive (and still a very good option) is because he designs standard monotube struts similar to the OEM design which are less expensive to manufacture. He uses Penske pistons and adjuster technology though which are simply incredible.

One thing I think we do poorly is get the point across that any customer can call us up and ask for the less expensive 7500 series double adjustable shocks. As long as our standard stable of parts can be assembled to fit your application a 7500DA shock is around $550 with spring hardware. For a little extra we can design and manufacture a body cap or new eyelet if its necessary to fit your unique car.

Originally Posted by DougW

Now back to Penske I think ever other shock manufacture is just a copy of Penske's last mistake they understand the science of control.

Hilarious! Thank you. Truthfully, the difference is in our philosophy. We can make shocks in the $1,500 – $2000 per car set range but we never will. There are many ways to design a damper and its various components and typically the best way is the most difficult and expensive. We also never advertise and we never give away a set of shocks to a race team at any level for advertising purposes like every other competitor. Most of the shocks I’ve developed over the past year have been from teams who suddenly have a healthy budget and ship us a competitor’s package they got for free because they know they’re losing time.

One (of many) crazy example was for a Tudor series car that gained 0.4 seconds through the infield at the Daytona 24hr race and 0.2 seconds just coming out of the corner onto the long straight because our shocks allowed the driver to get the power down sooner. The team was backed by the car manufacturer who doesn’t like American made Penske’s so they had to run the foreign competitors shocks in the front and have the sticker on the car but the team convinced the manufacturer to let them run our shocks in the rear of the RWD car. There are so many examples like this it’s crazy.

Daily driving: Hell yes Penske's are good for DD. The best design, craftsmanship, materials don’t make for a bad street driven car and a great track car. I expect to have Penske’s on my daily driven S60R and Vette within the next 2 months. I’ll even be using Anze’s front struts for the S60R because I can’t afford Penske struts either! One of the things I’m most excited about is testing out regressive damping on a daily driver. I may start aiming for pot holes if it behaves like I’m expecting them to.

Rebuilds: We also know of a number of customers who never rebuild their shocks. It can be done but replacing the oil every year or two is a really good idea and it isn’t expensive although the time without a driveable car can be a hassle. You also get all new shims and seals and you have the opportunity to discuss different valving with one of our techs if you don’t think the car is behaving the best that in can in a certain driving scenario.


Hope that helps. You guys have a spectacular platform I was considering getting before the perfect Vette landed on my lap.

[Racecomp Engineering]

Thanks for the post!

- Andy

[mav1178]

Originally Posted by RBbugBITme

Hello,

/sploosh

[fooddude]

Originally Posted by RBbugBITme

One thing I think we do poorly is get the point across that any customer can call us up and ask for the less expensive 7500 series double adjustable shocks. As long as our standard stable of parts can be assembled to fit your application a 7500DA shock is around $550 with spring hardware. For a little extra we can design and manufacture a body cap or new eyelet if its necessary to fit your unique car.

- What's the difference b/n the "dual-bleed" shocks used in the expensive brz kit, vs. the cheaper "double adjustable" shocks? Are those two the same thing but with different wording; or are they actually two different types of shocks?

- If you were to make a set using the cheaper 7500 shocks, would it be pretty much similar to the cheaper Anze kits?

- How much would your set be though, using the cheaper 7500 shocks?

[RBbugBITme]

Good questions.

First, I don't know if 7500's will work with the BRZ. It has stroke limitations that I know don't work with the car we're designing for now but street/track day cars can be different if you're not trying to tuck the wheels and destroy your geometry.

What is the difference between dual-bleed and double adjustable?
They both have two adjusters but handle their adjustments very differently.

Dual-bleed allows the shock oil to bypass the main piston by flowing inside the end of the shaft and out ports on the other side of the piston. So you're bypassing the shim stack that creates your shock force. This is designed to be adjustable in the low speed range only and compression and rebound are totally independent. You can see on page 6 & 7 of this tech sheet graphs that show how the adjusters affect the slope of the low speed range but not the slope of the high speed range.

The reason these adjusters are so awesome is because the low speed range is what the driver feels and the adjustment is done at the main piston which is of course attached to the main shaft. This leads to zero lag in any force changes and that is what the driver notices at the ragged edge.

Our double adjustable shock is older technology similar to what other manufacturers use. These affect the high and low speed range of rebound or compression, independently. You can see example graphs of what each adjuster does starting on page 9. Page 14 and 15 show a great cross sectional view of the components.

The rebound adjuster is still inside the shaft and is a much simpler design. The compression adjuster is in the body cap on the other end of the shock which is connected to a head/base valve. The head valve basically creates two areas within the shock that have oil with an adjustable valve between them. The valve restricts shaft displaced fluid. Shaft displaced fluid simply means the volume within the shock that the shaft takes up as the shock is compressed has to go somewhere, we control how that fluid moves into the second oil chamber.

Also, just because they're not dual-bleed shocks doesn't mean head valves suck. Every single NASCAR shock uses head valves as well as many many other types of full blown race cars and one benefit of a head valve is the ability to run lower gas pressures due to the pressure balancing effect the head valve has. The gas pressure acts as a spring on top of the coil spring you already have so higher gas pressure usually isn't a good thing.

Anze kits
I believe the only difference with the Anze stuff is the struts. He designs his own non-inverted struts that work with our internal guts. As I understand it, the rear shocks are typically supplied as components for him to build himself before shipping them out with his struts. He also focuses more on cars with unmodified suspension geometry so he'll make his own body caps/eyelets to work on applications we don't have time to look at since we don't cater to the masses.

How much cheaper would a BRZ kit be with 7500DA rear shocks?
I would guess $400-$1000 cheaper. I'm not really sure right now. Maybe ask one of our suppliers on this forum to look into group buy pricing. I don't know if any of our suppliers are members of this forum though...