[wrrrx]

Originally Posted by antonch

I have a G-tech unit that I've been meaning to hook up!

Yeah, me too. It's embarrassing how long I've had it and never used it...

I like this concept- sounds like fun!
Mebbe I'll hafta hook up that dang G-Tech... if I can find it.
Calibrated butt dyno won't work, I guess?

[Turninconcepts.com]

Tony and I were talking about this quite a bit today while waiting for the phone guy to set up DSL at the shop (which didn't happen, but that's another story).

Here's the deal - whenever, and I mean WHENEVER someone comes out with a new engine part everybody jumps up and down and screams "DYNO PLOT DYNO PLOT. NO PLOT NO PROOF. WWWWWWHHHHHHHHHHAAAAAAAAA I DON'T WANT TO TAKE A NAP!!!"

Makes perfect sense for the power guys. There's a part, they want to see numbers, and they ask for it as proof that the part works. How the hell do we not have this for suspensions?!

Are we all content to just sit here in the dark, and hope the stuff we're buying or installing or setting up is good?

Now, here's the thing - for the power guys dynos are expensive. Yeah, there's 1/4 mile slips, but not everyone is a 1/4 guy. In the end though a dyno is expensive, but it does two things for you.

1) allows you to tune without doing in danger on the road.
2) And the big one - gauges your car or a common set of cars/conditions that then lets you start with a baseline. From there you can look at the improvements made, and see where things fall short based upon what you do to the engine.

In other words - an engine dyno is a tool. A tool for measuring performance.

We need that tool for suspensions. Personally, I'd like to see it cheap and consistent so just about anyone can do it without having to resort to suspension tuner shops just like they have to with engine tuner shops.

In order to do that we need to come up with a common setup that just about anyone can do, and data log.

The natural outgrowth will be a suspension proven bragging area. THIS IS A GOOD THING!!!!

Take a look at the power area now. You have a goal in mind so you start looking at what others have done, and this gives you ideas for a path to go down. This keeps you from wasting money (how many people have gone through 3 or more turbos looking for what they want?). I'm talking the same thing, and keeping people out of the dark ages on what performs.

[Siegel Racing]

TiC, Have you looked at the Escort G-Timer? It's $35 That's even cheap enough for me to get one

Siegel

[stretch]

A cheap G-meter will never provide an accurate baseline, though. It's anecdotal at best. I like them, but I wouldn't use one as the backbone of a pissing match on the internet.

The problem is that your car's potential grip will change when you go through an elevation change or better asphalt. The elevation change is what concerns me the most. These G-meters show PEAK G's, not average, and I can get very high peak G's if I corner really hard on a road starting to go uphill. That puts more load on the tires, making more total grip, but this G-meter doesn't know that. (The more expensive G-tech's do, but they'll also plot an entire racetrack.) So, it's very easy for me to post a picture showing that I pulled a peak of 1.3 G's when really my average G's were far, far lower.

But I guess that's no different than using a Dynojet instead of a real dyno. Or icing down an intercooler. There always has to be some trust.

On the flipside, lap times are 90% driver, 10% car. So, they're useless too without knowing how those laps were achieved. More telling, I think, would be timing individual elements of a track. This is what magazines essentially accomplish with their standardized skidpad and slalom tests. I think those are good tests, but they aren't easy to replicate at home (since diameter and spacing matter and need to be consistent, plus the skidpad need be driven in both directions).

We can't use autocross to test- at least not with a cheap Escort G-meter- since the course changes each event, and besides, who doesn't get faster on each run by changing their lines? And tire temps will make or break grip more than things like damper settings, so it's hard to test consistently.

So, I guess I plan on using the Escort G-timer to compare values I see on smooth roads (probably off and on-ramps) I'm familiar with. There will be elevation changes, throwing off the values relative to other people on other roads, but they should be consistent day-to-day. It'll be evidence- not proof- of an item working since the values can't be logged (unless I put a video camera on it). Still, evidence is something. The best I'll be able to prove is that my peak grip went up by such-n-such points on this one turn. (But what if I traded less G's on corner exit, resulting in a lower average... there's no way to quantify that!)

I think the only way to accurately compare handling is to data log using either a GOOD G-meter on the same course as another vehicle. And that's obviously not going to be common except for someone who's really motivated to improve both their car and driving. That's why you don't see "proven power bragging" for handling. (Besides, posting a dyno print-out is easy since everyone who gets their car tuned will have one. Nobody gets their suspension tuned on a skidpad with a G-meter print-out, but maybe TiC should do that!)

[fullerton]

I like the idea. Maybe there could even be a traveling sensor, that would just be sent around to testers for the cost of postage.

[mEnTaL]

Another problem which will fog comparisons is like Esmooth said, throw on some race tires and get bigger numbers. I could see this working if one person does a base run, swaps what ever part he puts on, and then does the same run again. This way the variables are limited to the part changed and the enviro conditions. Maybe this is what you have in mind.

Where I see issues is with the fact that a suspension mod may have positive effects for one setup, but possibly negative effects for other setups (?really big FSB on stiff/soft, long/short travel suspensions?) or the magnitude of the change is drastically different across setups(which also occurs with engine mods). I think this makes it difficult to compare suspension parts directly for specific gains. The dyno that is typically used for suspensions is the butt dyno, but that is hardly standardized like an engine dyno.

Good idea otherwise, and would like to see it work out.

[red5001]

Originally Posted by Seigitor

Call me crazy, or naive, but isn't there a circle+speed test that does this? We would need some nice flat space to drive around on like a track or a parking lot. I'm talking about what they do in the option DVD episodes. I think they set the circle, and then drive around it at the fastest speed that doesn't loose grip. Then, average sustained G's are calculated from the time.

It wouldn't be hard to just use a skid pad type of test. You just need to know the size of circle the speed of the car/time. Then you can calculate Gs. I think I have a spreadsheet at home for this test. It's pretty simple and just need a parking lot. Granted grip will be different from one lot to another but it's cheap.

[sti robot]

Originally Posted by fullerton

I like the idea. Maybe there could even be a traveling sensor, that would just be sent around to testers for the cost of postage.

I like this idea. Consistent measurements are key.

I would like to be put on the list for this if it happens.

A standardized test should include:
-slalom time with g recordings and timing (300 ft total with 100 ft between each cone and 100 ft from start to first cone and 100ft from last cone to stop) - 5 runs...keep and average the top 3.
-skid pad on relatively new clean pavement-peak and average g's...set diameter of circle (suggestions?) and begin g measurements after first full turn...speed should not be set...but should be suggested to be around X mph.
-braking distance (60-0) - 5 trials...take the top 3 and average them

Tires are a part of your suspension and should be included in the test. If you have r-comps you should flaunt it. Those with racepipes flaunt them on the dyno...right?

[fullerton]

Originally Posted by sti robot

I like this idea. Consistent measurements are key.

I would like to be put on the list for this if it happens.

A standardized test should include:
-slalom time with g recordings and timing (300 ft total with 100 ft between each cone and 100 ft from start to first cone and 100ft from last cone to stop) - 5 runs...keep and average the top 3.
-skid pad on relatively new clean pavement-peak and average g's...set diameter of circle (suggestions?) and begin g measurements after first full turn...speed should not be set...but should be suggested to be around X mph.
-braking distance (60-0) - 5 trials...take the top 3 and average them

Tires are a part of your suspension and should be included in the test. If you have r-comps you should flaunt it. Those with racepipes flaunt them on the dyno...right?

Everything needed, including (folding?) cones and measuring strings could be included in the traveling kit.

[ConradSTI]

I love this idea.

Perhaps a regional meet could be held to accomodate as many users as possible with the "traveling kit." This would give a better average to conditions in each region.

[Turninconcepts.com]

so - bottom line - we need to establish a set of basic tests that can be done by anyone just about anywhere.

[tyler_sti]

Sounds good to me. Now who's gona bite the bullet for the test supplys? Maybe we all pitch in, and people who donate more recive sooner in line? Just a thought.

[sti robot]

^ As a vendor you may shy away from providing such a kit or at least do so with a caveat. One must provide their own safe and legal spot for such testing. You should not be liable if they get in to trouble because someone goes to local school, uses the lot as a skidpad and gets a ticket.

[sti robot]

Supply list:

-cones...foldable ones?
-g-meter with recording capability
-stopwatch
-roll up measuring tape/string

[fullerton]

the problem is the location. i wonder if the scca would let us do something before/after an auto-x.