jetskied

There has been lots of discussion with you should not put in springs only and that it is detrimental to the car ect.. Well since I can R&R spring and shocks in 2.5 to 3 hours I usually am helping out a friend in the project. Well recently I just did a friends car with only using the ROW M030 springs with OE shocks. I have done Eibach springs with OE shocks, the full M030, and a buddies H&R with Bilstein HD shocks. Now I usually have my friends just buy me dinner for the work, which a shop gets $400-$800 bucks for( darn I'm working for too cheap). Here we go with some data from from the Panorama article on suspension dated 6/02.

Eibachs with OE. I done this and it works OK if you want that lowering effect. I does handle better then stock due to an increase in spring rate and lower center of gravity. My main complaints was the fact that the height would scrape very easily since I have an aero bumper. Overall this package would work fine, but it does have some what of a bouncing effect that is not something that I prefer. It was not that severe, but you do notice it on very big dips. In most situations the ride was perfectly acceptable. In fact it rides similar to the M030. The Eibach springs are rated at 162-199 lb/in in the front and 240-302 in the rear. Now this is data provided by Eibach tech I spoke with. Given this data the rear springs are much stiffer then the OE which are 203 in the rear and the front would be stiffer, but not that bad as the progressive springs would intially feel soft in the front as the OE are close at 146. In the PCA article the OE shocks are rather soft in the rear and I did notice the bouncing effect more in the rear probably due to the soft rebound setting of the shocks.

M030: This set up works best as far as ride and handling characteristic go. It handles sharper then the above set up, but it has about the same overall grip. I like it better because the transfer of weight is smoother and feels more controlable in track or auto-x situations. The ride is stiffer then the OE, but a little better then the Eibachs. This may be due to the fact that springs are slight less stiff, but also keep in mind that the shocks are stiffer then the OE, so that makes the springs feel tighter. Spring data for the front is 170 and rear 260. There is less bounce effect due to the 36% stiffer rebound in the rear.

H&R with HD shocks; This set up was by far the hardest ride of all of them. I believe so it was due to high spring rates in the front and a rather stiff HD compression and rebound in the front shocks. The data suggest the HD shocks are at least 20% stiffer the the M030 shocks and the springs of 180-210 are much stiffer then the M030. This system handle very well and might feel better then the M030, due to a lower center of gravity with less roll, but it did understeer more the I would like, probably due to the stiff front end. The handling was better then the M030 and would work better in high speed situations like at some DE runs, but in some tight auto-x situation the ability of oversteer might make the M030 better. I prefer the less understeer and the better ride in the M030. There was much less bouncing effect on the rear due to a 20% increase in rear rebound, but the compression of the HD shock is close to the OE. This may be good because the rear springs would make up for the lost shock compression. The ride was not that harsh, but it was noticable compared to the M030. I would say if you were to rank it on a scale of 1-10 in harshness, 10 being racecar stiff the M030 would be a 4 and this would be a 5.5.

M030 springs with OE shocks: This combo surprised me how well it handled compared to a full M030. It was not that far off, but this combo was not as sharp and understeered more then a full set up. The reason is two fold that the stiffer sway bars help in the sharpness and the fact that the softer rear compression of the shocks will cause some understeer. Overall the ride was very nice, but I could tell the rear shocks did not have the right amount of rebound that is needed for the springs. The HD shocks would help. The ride IMO was not that much softer probably due to the fact that the front shocks are close in stiffness to the full M030 with a little less rebound accounting for some of that loose feeling. IMO its perfect for the guy looking just for a little upgrade.

Well there we go, my conclussions are that the aftermarket springs feel better with stiffer shocks to control the bouncing effect, but it is an OK to use with OE shocks for the guy who just uses the car as a daily driver with no tracks asperations and wants that low look. A better combo might be to use the M030 shocks with the aftermarket springs as they might just have the right compression and rebound to make it handle just enough oversteer to make a better track car. Going by data alone a good combo might be to use M030 shocks in the front and the USA M030 in the rear as the softer ROW shocks then the HD would take away some understeer with a little better ride and the rear US M030 has similar compression as the HD with a little more rebound control. Keep in mind that the Eibachs and H&R rates are close enough for me to believe it would be true for either one. The M030 ROW springs works great as an cheap upgrade to the OE suspension as it button it down nicely, but for a guy who is gonna auto-x it or DE it would change it out quickly and you should have saved time and go with a full M030. Now I know there are better handling system like PSS9 and JIC, but I like these as I use my car for daily driving with the wife too so the M030 works for me.

stuart_w

As someone who is planning upgrading the suspension and is totally confused by all the advice I found your thread was a really interesting. I hope this thread develops into a good discussion about the pros and cons of suspension upgrades.

Ubermensch

Thanks for the input based on your experience.

nycebo

Fantastic write-up. FWIW, I'm going the RoW route pretty soon.

jetskied

Stuart first you have to ask yourself what exactly are you gonna do. For a harder core driver who does lots of DE or auto-x you'll be better off going to a JIC or PSS 9 set up as you can adjust the ride height and stiffness. Another good option if you are not as keyed to adjusting shocks is the factory X74 which is stiffeer then the M030, but not quite as stiff as the JIC. The M030 does not lower the car by much. It will only be 1/4 to 1/2 inch lower then stock. Especially since your car is a ROW car. What the M030 provides is greater roll stiffness with out sacrificing ride by much. I have said aftermarket springs are the only way to go if you want a low look (1-1.25 inch), but it will suffer some ride comfort. They work best with better shocks, but I think it can be adjusted further for ride and bounce control by mixing and matching. I have not tried it though its all theory. I do think H&R with shocks might come close to a X74 set up, but by the time you buy all of the stuff you'll be with in $200-400 dollars of buying the X74 so why not get the package(x74 lower about the same). For the guy looking just to add a little performance with little cost the M030 springs alone works great, but not as good as the whole thing. The guy who just wants a low look at the lowest cost the H&R works fine, but the ride can get bouncy with large bumps or elevation changes at a track. It does work fine for average street driving. Hope this clears it up for you.

Robin 993DX

From doing much the samething on the 993 trying out different suspension options (same as you, for dinner or a bottle of Scotch), Jetskied you did great job outlining the difference. My results even on a 10 year old 993 is exactly the same as your description.

The only different opinion I have is on the PSS-9, many people spend the extra money for the PSS-9 for the adjustability. For a mostly street use situation I find the PSS-9 to be very stiff even at the softest setting, can't imagine anyone would turn it at all.

Currently I have the Bilstein HD and Eibach setup on my 993. (For, lower ride RS, RS ride height and longer lasting shocks, not too crazy about the compression and rebound on the Eibach springs. Personally the best combination I had on the car were the factory M030 setup, but unfortunately the shocks don't last too long....

Eli K

curious to see if anyone has tried running a complete ROW M030 but with H&R springs instead of what comes in the kit. seems like it would present all the benifits of a complete ROW M030 set up but with a lower center of gravity, less roll, etc.

stuart_w

this thread is proving invaluable to me. I track the car about once a month for fun on the track and intermarque sprints and would like to feel some improvement at the track, but I am not pushing the current suspension yet so I dont need a full racing set up. Having said that, the car is also my fun car that I drive on twisty roads in a non serious rally type setting. I would like to feel most difference on the road setting not at really high speeds but slighty exhilerating. I also want to drive it to work. I know its a big ask, so to summarise I want some improvement over stock, and still very drivable on the road and I am not a hard arsed racer.

Eli K

Stuart, PSS9's would probably be ideal in your situation....

TT Surgeon

Sure, it will work ok initially, but after a little while of riding on the bumpstops, the oe shocks will be done.Do you think the porsche engineers are so stupid to not know you can run the same shocks RoW and US? Those silly Germans!
To me, saving a few bucks and a couple of hrs ain't worth it on a 90k car at the track.
Seriouisly, shocks and springs should be a matched set, we're not talking about your Dad's Buick here.
Stuart, pss9's are ok, but check out x74 or RoW 030 on your car, that's the way to go!

stuart_w

Thanks for the advice Chris and its down to PSS9, X74 or RoW030. Being on the other side of the world where my Porsche mechanic has never seen or done any of these mods I have to make a decision based entirely on what I have read on this site. The Row is the most cost effective but for another $1000 I can go X74, but cannot evaluate the cost/benefit easily. But I really really appreciate everyones help and advice on this site. Half the fun is planning the mod.

PS I work in a hospital but all our surgeons seem to prefer mercs.

jetskied

Stuart its a real hard decission for you as you said you have not pushed the suspension that far yet and want to retain daily driving. The best way to go is drive someone else with different set ups. I would suggest that in due time your skill may out grow a M030, but the ride of a x74 may not be to your liking. Some people who has it says it ride fine, but like I said try to go in someones car that has one. I also suggest finding a suspension speciallist in your area that can help guide you as your current mechanic won't be too much help in your decission. IMO if you go with a PSS9 keep the front and rear spring at about 200 and 300 lbs./in respectively. You can use the shocks to increase the compression effect. A good set of sway bars would help out without loosing ride compfort such as GT3 sets.

stuart_w

I have a suspension specialist right here who is a bit of a Porsche nut and he tells me he can build a really really good suspension by using koni shocks and revalving them so that they 'blow off' going over bumps etc and then adding Kein progressive springs. It will be fully adjustable in secs and the adjustemnt is at the top of the suspension (thats a real plus). He is certian it can outperfrom anything else - for the money - and will be fine on the roads (a ***** cat) and harden up to seriously frim on the track due to the spring compression.

The guy is very talented and has the crdentials, he hand builds suspensions for a number of Porsches here in NZ including all the Bridgestone racing team (944s). He is currently building a competion set for a 993 turbo at a cost of 9grand a corner. I am very tempted to give him a go. He keeps the car for at least a week and works with the owner on settings on the road and at the track.

I am very very tempted and could make a good write up.

BBHelms

What is the best place and price to purchase the ROW M030's? (BTW, what does ROW stand for?)

Robin 993DX

Most of us on the 993 board purchase parts from www.carnewal.com ROW = Rest Of the World, basically means that us US Porsche buyers get the jacked up ride height (Because our great DOT), while everyone else in the world gets the good stuff.