Folks, I am in the middle of a dedicated autocross build to SCCA CSP specs. The power steering seals are leaking badly. My question is, should I replace the power unit with a manual rack (I already have one) or rebuild/replace the power unit. At least one accomplished driver recommends keeping the power unit for the quicker ratio. However, many of the top cars have the manual rack to save weight. I am curious about what everyone thinks. FYI a depowered rack is not legal for CSP.
The build so far:
‘90 B spec Miata
’94 differential with RX7 LSD
Delrin differential bushings
JIC Magic FLT-TAR monotube shocks
700lbF 450R springs
Energy Suspension urethane bushings
ISC offset Delrin front upper bushings
AWR adjustable upper rear control arms with Delrin bushings
1.25” NB “Big” Racing Beat Sway Bar, rear bar removed
SuperMiata end links
’03 motor
Megasquirt
949 Racing 15x10 wheels
275-35-15 Hoosier Tires
Autoconnexion fender flares

 

Saving weight is everything in autox, so go with what is the lighter option.

Also, cheat and dont get caught. But you might need the extra mechanical advantage with 8" wide meat-hooks on the front. start working out.

 

You can run the non powered rack with thirteens but with the big fifteens you need power. The top runners run PS.

 

How do you guys run Power Steering without the AC compressor?

 

Shorter belt!

 

I would run the power. I think only one car in the top 5 in csp doesnt have it, and I had to step over the pile of PS parts they just purchased way too many times in their garage last weekend. Honestly you only need it for steering speed or bumpy lots. The car will turn in faster than you can physically turn a manual rack. But unless its really bumpy I didnt feel the need for the power assist from a strength perspective. That car is actually easier to drive around in paddock than my car with only 225's so maybe its got magical steering geometry from the factory.

Oh yeah, add spare hoses to your kit of spare parts because 275s like to blow up rubber PS hoses.

 

Use the 2001 subframe and system. Much better.

 

Yes with the 275A6 you NEED p/s, maybe even 255 13".

 

I drove a competitive CSP car at Nationals a few years ago and it was on 275's with non PS and I never felt it was a problem (finished 5th with a bent subframe). I am digging back into my head, but I don't recall any of the top CSP guys Nationally run PS (that was 2010 though).

I think it really comes down to how much the weight matters to you. The steering ratio is quicker, but of course there becomes the issue of "feel" and "perference"

 

I know sheniker does now. And I'm almost certain that fraser does. Pretty sure most everyone else copies what they do. It weighs 6 pounds more than the manual.

 

Sheniker wasn't back then, but things change in 2 years. It does make the build a little easier though since you don't have to source a golden NB non-PS rack. I know when I drove the ex-Darby CSP car, it was a close copy of Sheniker's car at the time (minus some details that were added in 2011). Now if someone can just figure out a way to keep the hoses intact.

The car Fraiser is driving isn't even a 100% car. Last I heard it was still using a Torsen. By all accounts his a machine. Some people can just flat out drive. I co-drove with Jason Collett a for a few years in ASP and he is one of those guys. I could never catch him in many features.

 

OK, I’ll be repairing my PS and buying some extra hoses!
Are the top cars all running the NB subframe?
I was considering installing R type outer tie rod ends to help the geometry, an opinion on that would be appreciated.
I should probably jump in here with the build goals. The car is intended to be a budget CSP build, everyone hold your laughter. I picked up the car with the 03 motor already in it. The guy who swapped it could not get it running so the car was bought as a project (cheap). I’ll leave questions on the motor setup for another thread.
Most of the parts came from Craigslist or other autox cars. For instance, I realize the JIC’s are not the best setup but they came off a regionally successful SSM car. I could use a winter project so I might consider the subframe.

 

I know a national prep CSP car is on NA subframe, I dont think it matter much, use the lighter one?

 

In my car, with 10" wide slicks or 275 a6s, I want to try ps... running a looped rack now and its a damn workout that sometimes distracts from the necessary precision, IMO. I think it could really make a diff for most drivers, and I think it'd increase my abilities... feel through the wheel becomes less important when you're yanking that hard in slow corners.

 

I just put my PS system back in the car today.. Tossing the thirteens.
It was not needed with the smaller tires but after driving Kubo's car with manual and fifteens a few years ago...

 

lol, small world. That car rides a trailer with my old hardtop that I sold to Darby.

 

I wish I'd had the money to buy that car when he sold it. It was the most fun car I've ever auto-x'd over the years. Makes me want to build one of my own.

 

Its up for sale again. The guy who bought it just wasnt into it (and wasnt nearly as good enough of a driver to compete in CSP).

 

Haha. I am still in the "I wish i had the money" phase of my life. Out of curiousity, how much is the owner asking for?

The car has it in it in the right hands. I am not a great driver by any stretch, but I finished 5th in it. That was before he found the rear subrame was tweaked (we knew something was wrong, b/c of the rear camber) and before Brian Johns retuned it for the 2011 season and it picked up a lot of mid range power. Put it on a corn diet and a few minor tweaks and should be right there at the top.

 

I dont remember how much. But national level CSP isnt something to get into lightly. IMO its the most prepared SP class and has the largest amount of talented drivers. Put it this way, CSP was the fastest SP category at nationals this year, and even 5th in CSP was faster than Junior (evo school guy) in his SSP corvette. And the top 5 CSP cars were in the top 11 in pax(out of around 1200).