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dgross7's STF build thread

47K views 244 replies 24 participants last post by  dgross7 
#1 · (Edited)






Using this thread to document/share my progress both as a driver and of my car.

Improvements to date:

Chassis
Koni 8611-1256 race inserts
Corksport plates
Hypercoil 400f/650r
Goodridge ss lines
SPC rear arms
EBC yellowstuff
Tripoint RSB
AWR endlinks

Engine
Mazdaspeed CAI
Vibrant Headers/HFC
Racing Beat exhaust
SU trans mount
cp-e passenger motor mount 60 duro
cp-e rear motor mount 65 duro

Wheel & Tire
Rota Slipstream 15x7.5
205/50/15 RE-71r

O.Z. Alleggerita 17x7.5
225/45/17 Michelin PSS (travel tires)
 
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#162 ·
The best way to describe the new suspension as compared to the old: With the old, one tire screams while the rest are looking at him like what's wrong dude? Whereas now, the three tires on the ground are screaming in unison.

Let's hope this means smaller numbers :)
 
#163 ·
Another thing.

While installing the suspension, I noticed I recently gouged the CV boot (inner) and it was leaking/throwing grease everywhere. I ordered a new half shaft from rockauto and that is to arrive tomorrow. My predicament is this: I have the car scheduled to get an alignment and mount/balance new rubber tomorrow while I'm at work. I'm dropping the car off with the tires inside tonight and then picking it up after work tomorrow evening. The half shaft job will require some diassembly of the suspension, either at the balljoint or disconnecting the LCA from the subframe. Local events start this weekend, so I definitely want to get the alignment done, but I'll either need to get it realigned after the new half shaft is in or just hope I can get back to where it was.

I'm going to talk to the shop and see if they can help me out since it would only be a front end alignment and probably not terribly out of line. Worst case scenario, I have to drop a few more benjamins to have the front corrected again.

:bash:
 
#165 ·
Another thing.
While installing the suspension, I noticed I recently gouged the CV boot (inner) and it was leaking/throwing grease everywhere. I ordered a new half shaft from rockauto and that is to arrive tomorrow
.
When that happened to my car, I just had the inner boot replaced at a local shop.:grin:
 
#166 ·
Got a camber load reading.
It.... isn't what I was expecting to be honest, and it isn't that interesting.

Over the full sweep (I'll have to go read my measurements), basically from stock ride height to slammage, it was only a positive increase of camber by half a degree, and I'm at ~-2.5 degrees, this is up front.
Figured you guys over here would like to know.
I wouldn't call it, scientifically accurate, but, it's something.
Just took a digital angle reader, mounted to brake rotor, zeroed at around stock height, and just went up from there. No spring on coilover for a cleaner push without moving whole vehicle.
 
#169 ·
So I got the alignment on Friday. Unfortunately there was a mix up and the shop 'ran out of time' in mounting my tires. I also later found out after picking up the car that it is aligned, yes, but the steering wheel was not set straight and it tracks at about 5 or 10 degrees to the right. I'll be stopping by the shop on Monday to talk to someone about it. They have a great reputation so I'm not going to hold a grudge, just unfortunate I got such bad service.

This means that I am still on bald rivals from last year for this weekend's events. Yesterday was a smaller more casual autox and the car drove very well. I could tell the tires were not quite what they used to be though.

Today is the first event with my region, technically a practice event but still good fun and competitive. Bummed a bit I will not be on fresh rubber but there is nothing I can do about it. I will report back on the koni race inserts, higher spring rate and lots of camber up front, but it will have an asterisk for now.
 
#171 ·
Steering Wheel Off Center

So I got the alignment on Friday. I also later found out after picking up the car that it is aligned, yes, but the steering wheel was not set straight and it tracks at about 5 or 10 degrees to the right. I'll be stopping by the shop on Monday to talk to someone about it.
Bummer that they did not catch that, but it's an easy "at home" fix. Just turn the tie rod ends an equal but opposite amount to straighten the steering wheel. Shouldn't take much.

That said, you shouldn't have to do it.........
 
#170 · (Edited)
Finished 1st out of 4 in STF today, 31/168 in PAX. Second and third were both less than .3 seconds behind me so it was an awesome day of competition. Car fared well, weight transfer is obviously much faster so I flew through the slaloms. I am worried about one bit though. I set the ride height on the car where I felt comfortable; not too high or too low. But now I'm worried it is too low as I may be riding the bump stops under some turns. I have a picture of the car from today and I don't know if I like it this low under load. Might need to raise it up a bit or get a higher spring rate, currently running 400 up front. Any opinions?



The video of my fastest run is uploading as we speak. Here is the link:

https://www.youtube.com/watch?v=pOlX_yEhqXA
 
#174 ·
Intake and headers at the moment. I probably will wait to install headers until I have an exhaust to follow suit, but the intake should be on soon.

Tune is down the road. I also want to start shedding weight from the car.

So much to do and so little time...
 
#175 ·
Hershey was a success! The day started with an inch of snow on the car, temperatures around 28 with a high during the day of 38. It was f*&%ing cold. I didn't expect the weather that cold so working the course required a lot of day dreaming of sunny beaches lol.

1/4 in STF. No PAX results uploaded yet... come on Susquehanna SCCA Region!

https://www.youtube.com/watch?v=vs5Q5AQKTPY

The car drove stiff and there were a few times it was very bouncy, alarmingly so. I remembered when I put the coilovers on, I did not check where the comp/rebound was set.

The car also developed a subtle clunk. After further inspection, I realized I need to tighten the gland nuts way more than what I could by tapping each hole with a screwdriver and hammer. I bought a gland nut wrench from napa to solve this. I pulled the coilovers and tightened everything right up. So far, no clunks.

I assessed the comp/rebound setting and determined the compression was set to full firm on both sides! Brough those down 6 clicks and set the rebound one 360* turn away from full firm. The car is back to being bearable on the street, and I am super relieved.
 
#179 ·
No videos from today because this idiot forgot his gopro, but finished 2/4 in class, 39/257 in PAX. Just less than two tenths of a second behind the RSX that I've been chasing for a while now. Today's course was built for power; there were a few parts where it was nearly a sprint up the hill. The car felt fast and composed, but I feel I overdrove the car. WDCR's second event is the 26th so we'll see how that bodes.

Results: https://drive.google.com/folderview?id=0B0DAjl8siZI9YWR0NFJRWWo2dXM&usp=drive_web
 
#182 ·
Intake finally came in and has been installed! Low end and mid-range feels stronger. Maybe with the little added power I can beat the aforementioned RSX. He definitely has me on power while I feel my chassis is more equipped than his.

Someone uploaded a video of our fourth runs. You can hear the RSX launch around 15:10, and pass through the picture around 15:25. I am right behind him and pass through around 15:40. Both of us pass through the pictured part of the course in roughly 13 seconds but you can really see the RSX sprint up the hill after the slalom where I take much longer; this is what leads me to believe I have a stronger chassis.
https://www.youtube.com/watch?v=GmUSEzTcfd0&feature=youtu.be

Now we shall see how Sunday fairs...
 
#184 ·
No spring changes as of right now. I think anything over 400 is too stiff for the front and you lose the dive these cars tend to favor. Plus, because the car is pushing a bit right now, increasing the front spring rate would be counterproductive.

I've since moved the compression to full soft and the rebound half a turn away from full soft. If that isn't enough to put the car where I like it, I can adjust the rear sway, although I am already lifting a wheel so I don't know if that will be beneficial. A fellow autocrosser in my region mentioned that if the car is already lifting a wheel, stiffening the sway bar will more or less remove the benefits of having an independent rear suspension. I understand what he is getting at, but I remember last year when I stiffened the bar from the middle to the stiffest, it made the car significantly more lively; I was lifting a wheel before making that adjustment.

With the NJ pro next weekend, I'm headed to the Susquehanna region for an event tomorrow, if I don't like how the car is driving I'll increase the rear sway and see how it fairs at the pro. And actually, as I am typing this, I may increase the rear sway right now and if it's too much I can dial it back.
 
#185 ·
Ok so ended up sticking with the rsb where it was. Car felt very good but still just a hint of push. I had a co-driver today and I had the opportunity to see the on course. As it turns out, the car doesn't lift as dramatically as I anticipated. Granted, my co-driver was a a second or two behind me, I don't think I'm lifting much more, if at all.

Another note, I had the pressures a about 5.5 lbs apart, 36.5 in the rear and 31 up front. More than what I wanted which also justifies the changes I'll be making to the rsb. My thoughts are with a stiffer rsb and pressures closer to 32/35, the car will be right where I want it.

I have videos of my runs, but I've forgotten my times for them and susquehanna region is slow to upload results. Thus the video will follow shortly.
 
#186 ·
Used my friends computer to sign up for the Wilmington Pro no. 2, and..... it was slow af.

I see Bob, Colin, and Adam got in. I am on the waitlist, but I'm pretty confident I'll get in. That Pro should be a good match up!

Also moved over to bridgestones, still on 17s. I like them A LOT. They have a ton of grip to offer, I am curious how they'll fair this weekend on local sites that are not concrete.

Wilmington Pics :)



It rained a couple times...



Action shots, thanks Perry!



 
#190 · (Edited)
Alright so the Wilmington Summer Pro was AWESOME. Always such a great weekend running with all you STFers :)

Adam was super fast on Sunday and got me by eight tenths. I was comparing my raw times on Sunday and they were within three tenths of his fastest but I coned them away so it's hard to say how close I would have been if they were clean. Note to self: DO NOT drink a monster margarita from El Dorado the night before. I was definitely feeling crappy at the start of the day.

Lots of good talk though about my car. First off, 15s have become the priority. I had the exhaust ordered, but the purchase didn't go through. I bought it with contingency money, and the address listed on the card was my parents (I just moved to a new place) so the purchase was declined, and now I'm waiting for the funding to go back onto the card to complete the purchase. Anyhow, I purchased a set of 15s from 18Racing through their ebay page. The item was listed as the 'last set' of 15x7.5 rotas, they have been shipped and are scheduled for delivery on Tuesday. I will order a set of stones for them and tire rack ships insanely fast to MD, so I'll hopefully get to test out the 15 set up for a few days on the street just to get familiar with the car. I do have a set of 205/50/15 rival s (stickers still on them) in my basement right now, but I really like the stones and after speaking with my co-driver for the champ tour he agrees we should stay on stones. (Anybody want to buy them? I'll sell them cheap and will happily carry them to any upcoming events :D)

Otherwise, I think the Nationals set-up will be roughly what I've described so far. I'm concerned about the rev limiter so I might try and sneak in a tune if that's possible between the champ tour and Nats, Seats and lightweight mods are very unlikely to have together for Nats, but we'll see.

Ok on to the issues. At the pro I had the electronics go haywire again but this time it threw a code for a vehicle wheel speed sensor. I remembered that when I moved back to stock brakes I did not reinstall the dust covers. I'm wondering if, with the sensor right there, brake dust has gunked it up or something. I don't think it was heat related because the issue happens when the wheels hop a bit. I think it first happened when I went to warm up the tires before my first run on Sunday. New sensors are $50 each from MSM, so that will be something else I need to trouble shoot sometime this week. Does anyone know which corner is which? I believe it was "sensor A."

I'm getting super fucking stoked for Nats though. It's all I can think about all day every day. I'm just trying to slow down (in life that is) and enjoy this anticipation because I know it's going to come and pass very fast!

https://www.youtube.com/watch?v=a66zJx2Xcu4

No pics from Autoxpix yet. Will post those when Perry posts them.
 
#191 ·
A hypertech can raise the rpm limiter and speed limiter without actually doing the tune IIRC, so worth consideration.

As far as speed sensors goes; not a chance that's the issue. 04-06 models didn't even come with brake dust covers, so that surely can't be the issue.
Between maybe massive wheel spin on one side compared to the other is a possible culprit .. maybe?
Short of course of one actually being dead / unplugged etc.

As far as corners go, I'm fairly certainly all 4 of mine are the same, or at least fronts are the same as the rears...
BUT I could be hugely mistaken, so I won't say I'm 100% positive.
I remember replacing my front left at Mazmart, and I think we just grabbed whichever knuckle we found first with one in it. But don't count me on that, I may be mistaken.
 
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