Jasonoff

EDIT: Project scrapped. Not even close to being tolerable.

Has anyone done, or know of anyone who has done a manual steering conversion on this platform?

I am talking about modifying the rack to remove the hydraulic piston and gut the rotary valve so it's completely manual with zero hydraulic resistance. So not the same as trying to steer when the car isn't running (like a bypass loop). I was thinking it would feel similar to when the variable assist is disabled. Pain in the *** steer when going slow and feels slightly heavy at speed. For anyone who has had the ESP module failure, you will know how that feels lol.

I was thinking the main pro for this would be to reduce complexity (get rid of all the PS hydraulics) and make room for a larger transmission cooler up front since the PS cooler would be removed.

Or.... maybe this is a completely dumb idea, not sure yet.

hachiroku

haven't heard of this being done by anyone. great idea though. hopefully you have strong arms as steering with slicks or R compound is quite a workout even with proper manual steering. current F1 cars have power steering. alternatively, you could replace the hydraulic pump with an electronic hydraulic pump. many with Japanese cars repurpose the SW20 electric pump to power their fluid power racks and eliminate weight and packaging.

deadlyvt

Track car good idea sure, but on the street it’s pretty miserable. I converted my gutted 944 to manual steering and it’s like half the weight of a c63 and it become unliveable to drive on the street. I am getting older though so maybe It’s just that

Jasonoff

It's some what common for race cars.
A bunch of platforms you can just buy a manual rack. The massive unknown is how heavy will the steering be at speed when it's not pushing a piston through hydraulic fluid.

Common F1 cars see over 5G in corners LOL.
How did you convert it? Properly, or did you just bypass the hydraulic lines? My C63 will only be ~3200lbs so it's not all that heavy anymore.

I guess I could find a used rack and convert it. Then loop the hydraulic lines on the pump for an initial test with the converted rack incase I need to go back to hydraulics.

BLKROKT

As I mentioned, my car currently has the power steering speed-assist unplugged. It feels great at speed with a little more weight to it, but under like 20mph it’s brutal. I think you should go for it.

deadlyvt

The 944 had manual steering racks as an option so I just picked one up. As you said you could convert one with the steps you listed. As blkrkt says if you are not driving around town doing 10-20mph or parking it much then the manual shouldn’t be bad and you may even prefer it.

Jasonoff

Yeah, but you're a bad influence. Not that there's anything wrong with that
This is what I'm thinking. Having to muscle the wheel to load the car onto the trailer isn't much of a concern. As it stands, there's virtually zero feedback on the track. I bet I could lap with my thumb and index finger. Same goes for the braking system which is also another problem. I have to curl a toe in my shoe on the brake pedal to modulate. It's essentially a luxury car so the assistance systems are dialed to 11.

deadlyvt

Yeah I do agree with you on the assist being too much when you are pushing the car definitely takes some of the feedback and feel out of it.

Diabolis

I am going to echo what @BLKROKT and @deadlyvt said, with one small additional tidbit. The 924 race car that I had was converted to a fully manual rack with a quicker steering ratio (made by a machinist in the US that specializes in this - https://mwthemachineshop.com (the 944 Power to Manual conversion is what I had done)). The car in race trim was about 2250 lbs without a driver, and following the conversion, in terms of feel and the amount of steering input required was absolutely sublime... as in the best of any race car I've ever driven. The only downside is that once we went endurance racing with it, by the time you drove your second 80-minute stint on the second day on a tighter track, it was a workout and your arms HURT. I completely agree that the C63 power assist is too high for track use (although the steering feel is there - you just really have to have a light touch), but a manual rack on a 3500 lb car will indeed be a workout on a slower, tighter track.

If I was so inclined I'd probably reach out to Martin - head guy at the aforementioned shop - and at least talk things over with him and see if he has any suggestions. He does Porsches but at the end of the day it is just another steering rack.

Jasonoff

Thanks for the info I'll keep that shop in mind.

First step will be to find a used rack so I can chip away at converting it. I won't be doing any enduro sessions in the C63 anytime soon so I think I'm good lol.

hachiroku

ah yes...i'm sorry i realized now after i wrote...i meant for the C63. thankfully we have track rats like Jim leading the charge on doing things others haven't done yet.

i'd be curious to compare the feel of the C63's rack versus the W211 E63's as i do have feedback, although still not as much as a manual rack, but just the right amount of assist at speed.

deadlyvt

having driven both fairly extensively they are pretty similar however the 211’s has a little less feedback than the 204. May be slightly more assist or maybe it’s the softer chassis/suspension setup

hachiroku

to my understanding, the W211 E55's have horrible steering. Slow ratio and overly boosted. W211 E63 is fine for me being a big body chassis. could i use a little less on track, sure, but i'm happy with the amount of speed sensitive boost it does have. just right for my liking.

deadlyvt

Yeah I’m talking the e63 the older 55 is way more boosted and has way less feedback

Jasonoff

Started a convo with Martin. Getting some clarification but he said.
I'm not clear if that's a test with the rack still full of fluid or not. I've rolled this car off the lift down the driveway and could steer ok without it running.

Either way, I am working on gutting my current PS pump to turn it into a glorified idler.

He also mentioned they can do the conversion as well. Will get more details.

swedepat

After i took engine out in my car i hurt the solenoid(ordered a new one)
And as i drove it to paintshop and home again i canīt say it is brutal at low speeds, heavy yes, but not brutal.
But it might just be me that has some umphh in my arms also

Jasonoff

And that was with the restriction of manually pushing fluid through the rack.

How was it at speed?

BLKROKT

For those of us without Popeye forearms and actually driving these things on track, keep in mind that the heaviness at low speeds is exacerbated by neg cambered wide and sticky track tires and 30 minute stints including slow corners. I’d suggest keeping it unplugged for a full track event rather than just running to the store for milk, before forming any opinions.

Jasonoff

I'll just start using my left hand more to build it up...

Jasonoff

Pulled the pump apart. Looks to be in decent shape for a 2010 with 150k km on the clock.

hachiroku

wow that thing looks brand new inside.

swedepat

How do i best explain it?
Somewhere between no servo(brutal) and with servo, when rolling and engine running, but the response into the steeringwheel is great.
Standing still with engine off is a LOT harder, that would i say is brutal
But it is the same with solenoid connected or not.

But maybe as i mentioned above it is just me
I had a racecar earlier with slicks, a lot of camber and caster and awd, that thing was brutal when my antiroll bar was set on max, and didnīt have any powersteering at all.
(one almost thinks that one would snap the steering shaft)

Jasonoff

I started PS fluid changes pretty early in the cars lifetime and a filter (reservoir) change 3-4 years ago.

I also switched to the redline fluid.

GarlicBread

Question...you seem to be track oriented.

Why not just get a high-ish miled GT and swap your engine and effectively have a GT3 precursor?

Naturally there is the cost benefit question but if its a start and finish track situation that seems to be an option and you could do whatever you wanted with the engines out of the cars.

If its love, laziness, or cheapness I would agree with you but just an idea

Diabolis

Sorry - are you suggesting that the 4L TT engine from the GT (or the W205 C63) is a more reliable and/or cost-effective engine to have for track purposes than the M156? If you are, you're mistaken - although I am certainly with you on the OVERALL suitability and cost of the W204 platform as opposed to something like a C5 Corvette.

Unlike the current 4L TT in the production cars or the AMG GT4, the M156 engine was designed to be a race motor from the ground up, and Mercedes is still using it 15 years later (with a dry sump which technically makes it an M159) in their current AMG GT3 race cars. That right there says a lot about the durability and/or suitability of the motor. All other things being equal, the 4L TT from the GT would be a downgrade at best.