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Ok, "only" drove her 120 miles this morning. After a good warm up the roads were still a touch damp and during very well known roads i felt better grip overall, yet at the "edge" she started letting go very progressively (understeer), though the back end seemed a touch less grippy. Overall the grip was better than stock, and we must remember this was with wet roads. After about 40 more miles and different roads that were dry i really let her loose. Ok, here are the impressions:

Tires: Kumho Supra 712

Tire pressure (warm): 37.5 front, 38.5 rear

Air temperature: 55F

Air Humidity: 70% / dense air

Shocks: http://www.nicksforzaferrari.com dual adjustable and adjustable ride height

Springs: 300 lbs front, 250 lbs rear

Bushings: black Energy (graphite)


Everything warm and happy with dry roads. Turning the steering wheel is now easier/lighter at all speeds and feels about the same responsiveness. It is simply that less muscle is needed to make her "dance." She REALLY wants to dig in and turn now. While the car was very good before, now it is like she WANTS you to get on her and DO IT, versus needing more muscle to "wrestle" her there.

The ride now is more comfortable yet she also has better mechanical grip. Please allow me to explain. With the stock Koni shocks/springs and stock bushings, frost heaves and various bumps would upset the chassis to the appropriate varying degrees. This means that the car would get a tad unstable when driving over these bumps, the amount of instability (per se) depended on what the car was doing at the time (straight, basic turn, hard cornering).


With the new suspension the car seems to be more forgiving YET ALSO have more grip as the tires/chassis does not ham-fistedly deal with said road anomalies. As an example, during one progressively closing-out right turn there are some smallish and varying pot holes/bumps on the passenger side. With the stock suspension (due to a single side going over such a situation) the car would get unbalanced a bit due to "bouncing off" these road imperfections. With the new setup she seems to simply grip the road and that single side compliantly transverse the road imperfections. So the new suspension DOES NOT upset the entire chassis. Many of you New England folks know what i am talking about here. In the end she rides smoother, yet grips better.

Hard braking no longer causes the front to drastically (IMHO) dip down. This was a MAJOR pet peeve of mine. You are going fast and approaching a turn so you brake hard/down shift to prepare for the corner. Stock suspension was not the most solid/stable at dealing with this due (mainly) to weak front springs. With the uprated setup she dips down MUCH less and is better balanced all the way through this situation.

At speed: With the stock suspension the front end would get light over 100mph. It seems that there was very little down force and a "solution" i employed was to raise the headlights and this would help a touch. A small touch that made her feel A TINY BIT less floating. The new suspension allowed lowering the entire car down so the deep front air dam is 3.75-inch off the ground. Also, the front end is now approximately 0.75-inches lower than the rear (see pics below). At "proper" speeds she now is VERY MUCH planted. In fact as speeds increase i feel more down force is being applied so that the car is very solid. The difference between stock (light) and uprated (better down force) IS NOT SUBTLE!!! In fact there MIGHT be too much down force as top speed seems to be suffering. Easily explained as more down force means more power is needed to push the car ever-faster.

Example: Stock seemed fine through 135mph where between the aero package and lack of engine power would slow the process of increasing forward momentum. The new setup seems great to about 115mph and then it becomes slower (than from 0mph to 100mph) to climb to top speed. Like anything in racing, it is a tradeoff between the new suspension EASILY taking the twisty bit at high speeds while stock was slower (and took more effort in turns). In the end the ride height is adjustable and the new shocks are dual adjustable so she CAN be tuned for various situation/tracks. As the new suspension sits now, she is MORE than fine for the street. If this was track racing with MANY long straights and very few corners a different setup would be in order IMHO.

Anywho, those are some basics. Have not done the new Sparco race seats/Schroth 4/5-way harness upgrades to lower the car's weight by 50+ lbs while making hard cornering more comfortable for Yours Truly. The stock 308 seats leave MUCH to be desired IMHO. Also, the Yokohama 032R tires are back ordered and when they arrive will replace the Supra 712. Once the new rubber is installed i really want to track her with an instrumant in the car to get an idea about G force capability.
 

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Great review, Mr Music!

It would be interesting to know how your new setup compares to an "as-new" standard one, ie if you used new standard-spec Konis, etc what would be the differences. I don't know the mileage of your car but generally shocks/dampers don't perform at their peak for very long. :cry:

Did you adjust any geometry settings when you lowered the car? I'm thinking of static camber in particular which probably will have changed, affecting steering response. Also what about toe settings? Any idea what rating the new springs are compared to std? If you're not sure it can be easily determined from coil diam/wire diam/no.turns, etc.
 

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Steven,

Awesome post. Those shocks are just what the good doctor ordered. Now you have to use those adjustments to really tweak it. Speaking of adjusting shocks, do you track your car at times? If so let us know how they work on the track too.

I like the photos, your car looks good. Lets see some bigger ones in the future (if you have them). You can upload unlimited width x height but the file is limited to I believe 125kb. We like em big (at least Dirk does :nuts: )
 

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Discussion Starter #4
4kids3fish,

Glad you like the review. This was my first drive with the new suspension, yet i KNOW the roads VERY well. It is akin to driving on your own diverse race track many times each week and KNOWING nearly every part of her.

Am looking forward to getting the Yoko A032 R (H compound) tires on her. Agreed it would have been nice to try new Koni versus the new setup for direct comparison, yet every 308 i have been in seems to not be as, well, able to deal with things i felt with this new setup. This is especially true with hard braking and cornering.

As for geometry settings, KTR (http://www.ktrperformance.com/) took their time to get it all right (read: added labor $$$). In fact i also wanted her corner weighed and the necessary adjustments made with 170 lbs in the driver's seat. Steering response is MUCH improved versus as she was before as mentioned within my previous posting. Perhaps something was amiss before????? In the end she REALLY seems to be spot on as i know a few very flat roads and let go of the wheel (all was as it should be).

Stock Koni/Ferrari 308GTS QV springs are 175 lbs front, 186 lbs rear. New setup is 300 lbs front, 250 lbs rear. This is a "known" setup from Nick with his shocks/springs (www.nicksforzaferrari.com) and i must admit it appears to work well. Of course we must account for all new and better than stock bushing from Energy Suspension graphites part number 13-3101G (http://www.energysuspension.com) all around as well. KTR also did the tuning of the suspension as they have a mini track (per se) on their facility and i asked them to "drive it hard" to test it all. Of course Ferrari cars seem to enjoy this versus those who just cruise with their car.

FYI: KTR also did the 60k major in September and at that time i had them do more than necessary to insure all the demanding bits were like new (or better) including some dyno tuning. The "theme" here is to get her ready for track life yet still DOT street legal. It is a delicate balance and, as such, compromises are made along the way to keep her street legal here in the USA.
 

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Why would you make the front 300 and the rear 250? Control of under-steer? In your post Ferrari has the setup as stiffer in the rear than the front. The new setup is opposite, just curious as to the reason.
 

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Discussion Starter #7
Enzo250GTO said:
Why would you make the front 300 and the rear 250? Control of under-steer? In your post Ferrari has the setup as stiffer in the rear than the front. The new setup is opposite, just curious as to the reason.
Well, attached is the graph concerning stock shock/spring info. The GTB is 200 lbs all around, and guess Ferrari felt going SLIGHTLY larger rears was best for the GTS version. Again, the reason i went as i did is following that many others found that 300 lbs front, 250 lbs rear works. In fact one guy privately e-mailed me saying he has 450 front, 375 rear(!).

If you really want to get more info, see http://www.ferrarichat.com/discus/messages/256120/199158.html .

In the end everyone feels that having larger fronts is best and with the 308 here VERY hard braking does not have that horrible front end dipping (and yes, the 308 has uprated EBC Green Stuff pads and Goodridge steel braided lines). And to add, she has NEVER driven better and i'll gladly take the "Pepsi challenge" against anyone with stock suspension.
 

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Excellent report Steve! Great info! It is always great to hear about stuff that "works" (as well as stuff that doesn't)

I look forward to hearing more!
 

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Discussion Starter #10
Pete04222 said:
Excellent report Steve! Great info! It is always great to hear about stuff that "works" (as well as stuff that doesn't)

I look forward to hearing more!
Will do. Right now i am in the middle of installing the race seats and Schroth 4/5-way harness. Hope to finish this job in the next day or two. And yes yes yes, will have pics. Went to the hardware store today and spent about $30 in nothing but Grade 8.8 or better nuts/bolts/washers/etc. Amazing how much hardware you need for a project like this!
 

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enjoythemusic said:
Amazing how much hardware you need for a project like this!
Try completely disassembling and reassembling a Jeep. :D
 

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Enzo250GTO said:
Pete,

I think next years winter project should be to do this to the Ferrari.
No Way!!! My winter project this year will not be complete until July. I'm not going to do anything major to my Ferrari for quite a while!! I will be due for a belt change in 3 more years and at that point I will pull the engine and give the whole car the "once over". I may have it re-painted at that point also.

I am dreading my "Re-building the Ferrari" post.

I think for next winter I will do some more modifications to the house.
 

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First off Enjoythemusic let me say your QV is one of the best looking I’ve seen. Second off congrats on getting your car closer to your ultimate goal of performance.

I have a few questions for you and also some personal experiences to relate as to the set up of your car.

One of the things you didn’t list is your tire sizes. I’m assuming they’re something between 205-255 width 40-50 profile on a 16” rim for the front, and 225-235 width 40-50 profile on a 16” for the rear. Those sizes will have a big effect on handling as well. I have the same Kuhmos on my car (MR2 Turbo) and love them. I’ll be looking forward to your impressions of the new tires. Also, did you change your sway bars?

I’ll try and tic off items as close to their position in your original post to help answer some of your questions. The weight of steering resistance you mentioned I would put at the new set up from KTR. Springs and shocks operate to manipulate bump and rebound. More on that later. Items such as steering input have more to do with caster, camber, toe (in or out), corner weight, and other things like Ackerman angle. The 308 had buckets of caster. This causes the steering to be heavy and also gives the car stability in a straight line and at high speed. Caster is the angle that the upright leans back toward the back of the car. In other words the bottom of the upright is a little bit in front of the top of the upright. When this is the case, as you turn the wheel (lets say to the right) the left wheel not only is turning but pivoting- forward and to the right. The right wheel is pivoting- back and to the right. This creates “negative scrub”. In other words the tires don’t want to turn and you need more force to do so. It keeps it tracking in a straight line. The closer the uprights are to 0 deg the easier they’ll be to turn. I’ll bet anything they eliminated some of your caster. But, you're more stable at higher speeds... more on that in a minute as well.

The new bushings alone would have made a tremendous difference in the way your car handled. Old rubber bushings that are worn out can give a millimeter here and a millimeter there. Big deal? You bet! Think bout your four pick up points on each corner (two on your upper A arm and on your lower). If all of those are allowing movement of 1mm your suspension could be 8mm out of whack. And that’s just the front. Throw the back components into the mix and you can see why urethane bushings are such a good investment. So. If your car was squirrelly over the bumps I’d say this was the primary cause. Or maybe a bad shock that wasn't quite up to par. As those old pieces of rubber compressed and flexed your car really didn’t have any set camber, caster, toe, etc… it probably wasn’t until the car took a full load in a corner that it “set” into some form of static alignment due to loads being applied to the different pick up points. Now that all of that is working properly the rest of your suspension has a chance to do what it was designed for. Which brings us to your new shocks (dampers really) and springs.

You said your ride improved. Normally stiffer springs mean stiffer ride. Are they progressive springs? Ok, here’s how spring rates work. If a spring has a rate of 300 that means it takes 300lbs of force to compress the spring one inch. 600 to compress it two inches and so forth. A progressive spring has a varying rate. Most manufacturers make springs in 50lb increments or some in 25lb. They also make springs in a variable rate. And with Coil-Overs such as yours you can get a “Tender Spring” and Main spring. This combination gives you a progressive rate up to the main spring rate at which point when the tender is fully compressed the main rate is the final spring rate. Confused? Go here:

http://eibach.com/cgi-bin/htmlos.exe/00151.7.6225172582100012211

I’m betting you have a progressive spring set up on your car now. I’ll bet the initial rate is softer than the stock spring and gets progressively stiffer as the spring compresses. Giving you a better ride (due to the softer initial rate) and better handling as you get more aggressive with the car (as it gets stiffer). Talk to Nick if this is what he’s sold you. If not then I'd say you have a placebo effect from your new suspension. :) Also you can now play with this spring set up yourself. The other new item on your car are the shocks. With, it sounds like, adjustments for both bump and rebound. I said earlier that it should really be called a damper because that’s what it does. It dampens, controls how fast the suspension goes into bump and then into rebound. I can go into this if you like but it will require a lot more explanation than I have time for at the moment. Let me know if you’d like me to talk about it though.

High speed handling. I’m very surprised your car was a bit floaty at over a 100mpr in stock form. That one I don’t have an answer for. The 308 is normally a great platform for high speed driving: http://www.bobnorwood.com/Ferrari 3 Liter power on the salt.htm

When you lowered your car you lowered your center of gravity. This is the second thing I always tell people to do if they want to make their car handle better (bushings is the first). This is why SUVs suck, as we all know. You also lowered the front lower than the rear. What did this do? It shifted some of the weight from the rear of the car to the front wheels. Think about it this way. You’ve helped a friend move a couch haven’t you? Well when it’s level the weight is evenly distributed between the guy at the front and at the rear. When the guy at one end raises his end (say, going up a step) the weight shifts to the guy on the lower end. That’s helped your stability. I’m assuming you had the Euro spoiler on the car prior to this new set up. With that alone your car’s front end should have been nice and firm. (I’m still scratching my head). When you dropped the front another thing happened. This time to your aerodynamics. Here’s how downforce works on a car. Air flows over and under a car. When air flows under the car faster than it does over it creates a lower pressure under the car and a higher one over the car. The higher pressure then presses down on the car. Drag and downforce are not directly related. Aerodynamics and drag are. See here: http://www.mulsannescorner.com/data.htm for some awesome fun stuff (also www.mulsanecorner.com ). When you lowered the front you exposed more hood surface area to the air flow. Also your front windshield angle was altered in relationship to wind deflection as well. Under the front the gap was made smaller. The bottom of your car now angles up from the front. This causes less air under the car than there was before and the air now has to accelerate to fill the new space underneath. You’ve created a little venturi under your car. Also remember though that it’s pulling air under from the sides as well at this point. Your addition of the Euro spoiler did that on you car to start with. By dipping the front you increased the effect and also slowed the air over the car even more by increasing the frontal area of you car. But, this increased frontal area and more aggressive windshield angle has increased your drag. By how much I really can’t tell you. I also can’t say if this is the sole cause of the reduced speed and acceleration at higher speeds. How aggressive an alignment you have will also come into play. More toe in means more rolling resistance and such. “Going fast requires a TON of power. Air resistance goes nuts with speed, increasing exponentially as the cube of the increase in speed. Air resistance over 120 mph becomes extreme, which is the speed at which a human body free-falling through the air (prior to pulling the ripcord!) reaches terminal velocity and will not fall any faster. If you could go 100 mph on, say, 80 horsepower, to double speed to 200 mph requires 640 horsepower! If you could go 150 mph on, say, 210 horsepower, doubling speed to 300 mph requires 1680 horsepower!” (http://www.bobnorwood.com/The Fastest Little Sports Car in Utah.htm)
And going 100mph on the 80hp has to do with your aerodynamics. By increasing your frontal area every extra square inch you’ve now exposed is being attacked by the air resistance mentioned above. It takes more of your hoarsepower to overcome that resistance to reach that speed. If you really need that top end speed I’d say start dropping that back end down bit by bit and see how it feels. But that extra resistance becomes an advantage when you enter into a high speed braking zone! It will help your car decelerate faster from those high speeds.

“How it feels.” That’s the most important thing here. I could go on and on with set ups and numbers. Having been a race “engineer” I can tell you two things that are for sure. No two drivers are alike in their abilities and driving styles and even though it works on paper doesn’t mean it works in the real world. I can’t tell you how many times we did calculations and put a killer set up on a car only to get it to the track and the driver to go like a pig. The sheet would be thrown out the window and we’d go with our gut. Usually the gut was right. A set up on your car that will enable me to drive around a track at X time doesn’t mean you can get the same time. Do you like a tail happy car? Or a more balanced? Can you drive through problems, like Senna, or do you need to fix them before you can go fast, like Prost? Both are world champions who drove the same cars with totally different set ups and still were as fast as the other.

I hope your driving skills are up to the challenge ahead of you. And once again, Congradulations! :green: Once you start making adjustments you might find your times going backwards instead of forwards! Don’t despair. This sometimes happens and is part of the learning curve. I’ve written a small amount about a very large subject. I recommend the following books by Carroll Smith:

Tune to Win
Engineer to Win
Drive to Win

They cover everything you’ll need and were my bibles when I was racing and working as a mechanic.

Looking forward to the "You don't know what your talking about" post that will follow after this... :wink:
 

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Discussion Starter #18
Senna,

WOW, where to begin? First, thanks for the compliments. The VIN is a VERY late model (only ONE car newer than mine is till alive that i am aware of... and it is indeed a Euro model). Have spent MUCH time (and buckets of funds) putting on all new emblems, completely new lights/assemblies, aligned all the gaps, etc etc etc. She IS NOT a show car!!!!!!! Work at home and d drive her 5000 miles last year (and consider we have 3 months of DEEP snow here in the mountains of New England).

As for tires, am debating buying 18 inch rims. You are indeed correct, the Etoile rims are 16 inch with 205/55 front and 225/50 rear. PLEASE MAKE ANY SUGGESTION HERE AS I AM SERIOUSLY CONSIDERING NEW RIMS for the Yoko A032R rubber. As for sway bars they are the larger Ferrari stock for the 308GTS QV. Have debated going larger, yet want to get a handle on things now before adding more. As you can guess (and add to this the recent 60k THOROUGH major service in Sept 2003) and she has been a money bucket. Not that i mind as, quite frankly, i am enjoying EVERY minute of it :)

As for the alignment, again you are right in that the old bushings needed to go. Am sure KTR setup the car to stock camber/toe/etc... or near it but with a eye towards me LOVING the twisties. FYI: KTR are true racers and take BIG BIG trucks to race events with various cars. They are not "race inspired" as some commercials seem to say about automobiles.

Am familiar with how springs/shocks work. Also familiar with various changed needed, though as you say, what looks great on paper could be a pig on the track/road. i prefer the ability to DRIVE out of situations. Perhaps i am a "control freak" ;-) As for progressive versus normal springs, called Nick to verify, yet he was out of the office. As you say, with this new setup i am now able to play with nearly any type/rate of springs. The stock units were not user-friendly in this manner.

As for high speed front lightness, the MAIN problem was that the front was physically HIGHER than the rear. i NEVER carry the spare and this probably cased the reduced weight to have the front springs go up a tic or two. Yes the new setup allows for height adjustment and yes, have the front lower than the rear by about 0.75 inches. And yes, i can feel there is now a small touch of oversteer right now, but it is slight and will play around with tire pressure to see what can be accomplished there.

MANY THANKS for recommending the books by Carroll Smith:
Tune to Win
Engineer to Win
Drive to Win

Will get them from Amazon.com or other resources. And yes, you do seem to know what you are talking about. i AM NOT an expert... but i played one on TV ;-) Actually, have been an enthusiast for decades and have learned MUCH over the years. The Euro 308GTS QV is really my "fun toy" and a way to just live and learn. In the end i am having fun and that matters MORE to me than somehow being UNHAPPY driving but fighting the car around a track 1 seconds faster than "fun". Hope that makes sense.
 

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Discussion Starter #19
senna21 said:
I'll get into my ideas as to why your braking is better now as well when I have more time.
FYI: Braking (stopping distance) is pretty much the same, it is that the upgrade from 178 lbs springs to 300 lbs springs help greatly at reducing front end droop during hard braking. In fact i now feel i could upgrade the front brakes for added benefit, but how much can one man pour into a car? Ok, it cost $3k... Another $3k... Just another $3k...

Did i mention new Brembos for the 308 are $3k (front) LOL
 

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enjoythemusic said:
senna21 said:
I'll get into my ideas as to why your braking is better now as well when I have more time.
FYI: Braking (stopping distance) is pretty much the same, it is that the upgrade from 178 lbs springs to 300 lbs springs help greatly at reducing front end droop during hard braking. In fact i now feel i could upgrade the front brakes for added benefit, but how much can one man pour into a car? Ok, it cost $3k... Another $3k... Just another $3k...

Did i mention new Brembos for the 308 are $3k (front) LOL
Send our sponsor DexM an email. This is their speciality (upgraded parts for Ferraris) and they may give you a discount because you went through Ferrari Forum.
 
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