posted on March 15, 2012 00:00
Hypermiler's suspension definitely needed a refresh. After 170,000 miles, the already pitiful stock bushings were showing evidence of imminent failure, and the boots were ripped on most of the joints.
|The stock rear control arm bushing was tired of its hard life and had begun to crack. Note the large air gaps in the bushing to increase compliance. This bushing allowed as much as 1/2" of deflection with a small pry-bar.
Before delving into any project that is VW, make sure to order all one-time use torque to yield (TTY) bolts ahead of time. In addtion, since an alignment would be needed after install, and the control arms needed removing to install some of the parts, new ball joints, tie-rod ends, and strut/shock upper mounts were ordered to give the shiny new upgrade bits a fresh start. As usual, frustration springs eternal with the expensive array of hardware that needed replacing, and $80 was spent on replacing TTY bolts alone. Make sure everything is assembled correctly the first time, as a mistake likely means needing to buy another TTY bolt. This is generally compounded by the fact that most local VW dealers don't have sufficient stock on hand.
For this update, OEM parts were chosen for everything with the exception of Moog tie rod ends for their zerk fittings. While zerk fittings would be useful on the balljoints as well, previous experience has shown that these fittings are susceptible to damage, ruining the balljoint.
OEM replacement parts were chosen for everything except the tie rod ends.
|Moog tie rod ends were chosen for their zerk fittings to ensure the joint never goes dry.
The centerpiece for our suspension upgrades came from Suspension Techniques (ST) in the form of their Speedtech Coilover system. Made by KW, these coilovers are virtually identical to a KW V1 setup with the exception of the materials used to construct them (the ST coilovers are galvanized steel instead of INOX), and feature all of the things that make the V1 setup work well: tender springs up front, progressive rate rear springs, non-metallic spring perches, and pressurized dampers with KW-tuned valving. The best part is the ST coilovers come at a very reasonable price comparable to many damper and spring combinations, but allows the driver to choose a ride height between nearly stock height and 2.5" below stock height. Most spring and damper combinations available featured relatively soft spring rates and lower the car too much, resulting in poor geometry and an overly familiar relationship between the driver and the car's bumpstops.
When most everyone thinks of coilover setups and street cars, they think of a gritty ride, with clunks, rattles and squeaks from the spring perches resulting in huge amounts of APM, especially in parking lots where road noise doesn't drown these sounds out. Luckily, ST sought to eliminate these common coilover problems by utilizing the stock upper mounts, tender springs and progressive rate springs (front and rear, respectively) that maintain preload even when the wheel is completely unloaded, and non-metallic spring perches on the struts up front. Non-metallic perches are not necessary for the rear end of the car because the spring does not turn like it does up front.
|ST Speedtech coilovers are made by KW, and are almost identical to their V1 setup. The ST coilovers feature galvanized steel bodies instead of INOX stainless steel.
Thursday, March 15, 2012 8:25 AM
Did you say those Enkeis and Nittos weigh more than the stock wheels and tires?
Thursday, March 15, 2012 8:52 AM
@ Dusty: Yep. Stock wheels were 15x6 and tires were 195-65-15s, aluminum (16.5lbs, not bad for OEM), and the tires were ultra-cheap Chinese models with hardly any sidewall support. They were technically too light (weight rating wise) for the car.
Going to a 225-45-17 with 7.5" wheels, I was expecting a minor weight increase.
Thursday, March 15, 2012 9:48 AM
Those are some very light OEM wheels!
Thursday, March 15, 2012 12:13 PM
Aye matey, ye needs to trim yer sails a bit in dat first pic! Yar...xD
Thursday, March 15, 2012 12:56 PM
I heard roxy stickers add a few mpg.
Thursday, March 15, 2012 1:11 PM
@ Steve: This chair be high, says I. Yar.
@ Steve Choi: Kiss my entire ass. :)
Thursday, March 15, 2012 2:50 PM
Steve, I know wheels (most of the time) are choose based on price and strength-lightweight criteria.
Any reasons why you didn't go with the proven RPF-01?
Thursday, March 15, 2012 3:12 PM
How many Steves do we have in the house today!?
Steve R - Excellent coverage of your build! I was starting to think (around page 6) how much I'd like to see some comparative data and then you totally pull through :-) Despite your attempt to justify your fairly "unscientific" method, I still find worth in the data despite any arguements against. Now, I'm looking forward to how you get those front tires spinning again :-p
Thursday, March 15, 2012 3:38 PM
@ JDMized: There were a number of reasons. Chief among them was budget for the car. The Fujins are part of Enkei's new lower priced line of tuner wheels. Not as light as the RPF-1, but definitely cheaper:http://www.amazon.com/Enkei-FUJIN-Silver-17x7-5-Wheels/dp/B005ME9GOK/ref=pd_sim_sbs_auto_5http://www.amazon.com/Enkei-Silver-17x7-5-5x100-Wheels/dp/B005KDUBG0
Same quality and MAT construction, so for me the extra couple of lbs was a fair tradeoff. Since the budget for this build is extremely tight (the car's primary reason for existence is to save me money), the Fujins made more sense.
Second, I like how these wheels look. Always been a 6-spoke wheel fan (my SE-R has Kosei K-1s on it).
Lastly, the RPF-1s only came in a 48mm offset in the 5x100 pattern and 17x7.5 size I knew I wanted. I didn't want to run spacers, and with the 40mm Fujins I have, the tire is about 10mm away from the strut. The RFP-1s would've definitely required spacers.
@ Der Bruce: I would say that I took an unscientific test, and made it as scientific as possible. Much like dyno charts, it's only reason was to measure improvement, not for winkie measurement. ;-p
Thursday, March 15, 2012 7:14 PM
Steve, impressive grip. Over a full g and serious improvement, wow. And, those rear sway end links are SO cute, I know a cute blonde with a white Jetta who will...oh, sry nvm xD
Thursday, March 15, 2012 8:21 PM
Nice writeup! Your project reminds me of an article in a German car magazine where they kind of ghetto tuned a Golf 3, maybe you can get some inspiration from there -> http://tinyurl.com/6lzyeuo (watch out for google translator).
I am looking forward to the rest of your build! WPC treat ALL the parts, I guess...
Friday, March 16, 2012 8:42 AM
@ Steve: Yep, though that full g would likely show up as somewhere around 0.90-0.95 on a real 600' skidpad test. My numbers were skewed a little being peak numbers. Either way, the grip this thing has impresses me. There really is no need to get a summer-only tire with these things unless you're actually going to drive them on the track regularly.
@ Julian: Err, I hope the only reason this car reminds you of that one is that it's also a TDI-powered VW... ;-p
The entire build is street-oriented and budget friendly, but nothing embarrassing. No duct tape visible to the outside, non-matching coroplast, stripped interiors, etc. This car is to be nice, comfortable, quick, and REALLY fuel efficient.
Friday, March 16, 2012 9:47 PM
no worries ;) I was just surprised how much fuel saving they were able to achieve with those crappy methods when I read that article, so I wanted to share it. Many of them don't qualify for street use, of course.
There were a few ideas I liked though, like closing up the front as much as possible to reduce cd, and trying to make the underbody as flat as possible.
Monday, March 19, 2012 2:40 PM
Yep. I plan to use some of those ideas, just not so ghetto.
Funny, but one would think something like that would be verboten with ze Germans... :)
Tuesday, March 20, 2012 6:46 PM
Cool right up. Why did you ditch the oem wheels? Was it tire options, appearance, or something else?
Just concerning the wheels and the ability or inability to put a similar tire on the oem wheel: Ignoring the aesthetics, with everything else you did, could you have skipped the aftermarket wheels and upgraded the tires on the oem wheels with similar results?
Wednesday, March 21, 2012 9:53 AM
@ eeeen: I upgraded from OEM wheels for a number of reasons.
1. Fitting a 225mm wide tire would require a 7" wide wheel. Fitting them on a 6" wide wheel wouldn't have really improved handling.
2. Available tires. Not much that is higher performance is available in the 195-65-15 type sizes. I could've gone wider/lower profile, but even still, not much is available.
3. Aesthetics. The stock wheels looked undersize for the vehicle.
Ignoring aesthetics, I don't think I could've been able to combine the all-season capability, treadwear and performance of the Motivos with another tire on the OEM wheel. The Motivos don't come in 15" sizes, and most of the offerings in those sizes aren't the greatest tire. I've been REALLY impressed with these tires so far.
That being said, I probably shot myself in the foot with my MPG goals a little by going wider and higher performance with my wheel/tire combo (though the mileage penalty hasn't coalesced so far), but the tradeoff was worth it to me. We'll see if I can make it up elsewhere.
Sunday, April 22, 2012 9:20 PM
My e30 has a similar strut setup.
I found a 13/16 spark plug socket and a combo wrench with a hex key worked great. No need for a pair of vice grips.
Tuesday, April 24, 2012 4:10 PM
Ah, that would've probably worked as well. Didn't even think of that.
Then again, this method is far more dangerous and ghetto, so it's much more in line with my thinking anyway... ;-p
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