damian

iTrader: (2)

hey steve, keep a close eye on the outer edge of your tires if you have only -1.6 camber.

pluto

I got my tires used from a tire place in Wisconsin. They are very friendly and usually have every tire combination in stock (or can get them quickly). www.jbracingtires.net

My hoosiers prior to these slicks were brand new from Hoosier when they were onsale 2 yrs ago.

pluto

Yea, that's how I corded my hoosiers. At least I have slightly more negative camber than before so it should help a little.

afgmoto1978

iTrader: (6)

Here are the temps and tire pressures for todays practice. Tires were set at 36psi at all four corners before starting, with full hard in front and one full turn from hard in the rear.

The track: http://www.portlandraceway.com/index...d=25&Itemid=45

Front Left - in 169F out 160F, 38 psi
Right front - in161F out 130F, 37 psi
Left Rear - in 174F out 157F, 38 psi
Right Rear - 178 in 140 out, 37.5 psi

I'm thinking leaving Left Rear and Right Front tires pressures, but tire pressures will be increased on the Right Rear .5 psi and Left front 1 psi. And increasing the rear shock stiffness to half turn from hard rear. Overall the car is well balanced with a bit of mid-corner oversteer if corner speeds are too much (what a concept!). Oversteer is very slow and once throttle input is reduced the rear come back inline nicely.

Howard, what are your thoughts?

Howard Coleman

iTrader: (6)

thanks for the data

once i get my temps i average them for each corner to get the big picture first. it would have been optimium to have had your center temperatures especially when dealing w pressure.

so here's my process:
***LF******RF
160-169 | 161-130
***LR******RR
157-174 | 178-140

first, let's remove camber from the readings to get the overall picture. we will revisit camber afterwards. we do this by adding temperatures at each corner.

329******291

331******318


1269 degrees of total heat.

620 degrees of front heat
649 degrees of rear heat


48.86% front heat
51.16% rear heat

the car should be mildly oversteering from the above data. (my i preference)



660 outside (left) heat 52.01%
609 inside (right) heat 47.99%

this will vary depending on a number of factors: tire stick, how hard the car is driven, track condition. you are transferring 800 pounds laterally.


cross weight heat (outside front and inside rear)

329 and 318 is 647/1269= 50.99%. that's normal for a 50/50 car such as the FD.
any weight you can move to the RR will make you go faster.

the right front is the challenge. it isn't pulling it's share. the more temp you can get in the RF the faster you will go. do the tie wrap on the LR shock piston rod and check to see your travel at the piston rod is no more than 1.4 inches. if it is, you need less travel in the LR which will diagonally plant the RF.

camber:

take the inside readings and plot them:

169******161

173******178

total inside heat 682

%

24.7****23.6

25.5****26.1

48.4% front
51.6% rear consistant w a touch of oversteer.

cross inside temps 51.6%

LF perfect, and it is the most important corner camberwise.
RF camber closer than you'd think. the reason the RF is so cool on the outside is it is off the ground. if you look at the inside temp on the tire (161) it is fine. so i wouldn't change RF camber until you get it planted and can get some real numbers. i'd take 3/4 of a degree of camber out of the rears.

tire pressures... i would start 2 psi lower in the rear and hopefully you can post some center temps so we can zero in on the tire pressure.

good luck and thanks for posting your results.

based on the numbers there's lots of time left in the car.

howard

afgmoto1978

iTrader: (6)

Well your looking at the overall winner in modified class and RWD. 1:28.56, Second place is an STI with a very very fast driver in anything he drives, 1:29.54.

Unfortunately we didn't have time to check temps in between runs, but pressures where recorded.

Qualifying Start

LF - 30 psi
RF - 30.5 psi
LR - 31 psi
RR - 31.5 psi

First run

LF - 34 psi
RF - 35 psi
LR - 36 psi
RR - 36.5 psi

Second Run

LF - 35 psi
RF - 35 psi
LR - 36 psi
RR - 36.5 psi

Best time 1:30.754


Main event, wining run - Sun going down - track was cooler, sorry did record it. Added 1 psi to the right tires and .5 psi to the left tires.

During qualifying the break pads would lose their bit within 1.5 laps, well before the tires got up to proper temps, so the first 3 laps I when fast enough to get the tires up to temp, but kept the brakes and engine cool. Racing brake BBK kit with ET700 pads, I wanted to get DTC-70 before this event, but wasn't able too. Anyways, once the tires felt ready I went for it. I ended up with a 1:28.56. Next lap the line to the boost controller split and I saw 235 oil and 200 water. I need bigger oil coolers and hard lines.

Thanks Howard for the pointers and starting this thread.

Adam











The COBB GTR with R-compounds and light mods did a 1:22, Damn.

the faster one

very interesting topic here

Howard Coleman

iTrader: (6)

congratulations. i am jealous and really have the itch to get out there. i dyno tuesday, finally, and after that it is purely finding the next track event.

it's nutty that while i was typing post 380 a friend showed up w a white GT-R. i took it for a 100 mile drive thru the Kettle Morraine (twisties) and wrung it out pretty good. he had the "all season" tires on it and i checked them w my durometer and they read 54! (that's sticky!). 'nice car, lots of instrumentation, sticks like glue etc but it is just too big for me. i prefer the weight and size of my FD.

since you are developing more temp in the rear it would seem that you would benefit from softening the rear rate via less rear air pressure. you would promote more rear grip and balanced temps.

i am sure everyone reading the thread appreciates you sharing your day, data and pics.

thanks again,

hc

dradon03

iTrader: (2)

It is nice to see that the FD can still hold it's own. Very nice wheels are they the Volk RE's or the Enkei GTC's?

It is ridiculous how fast that GTR is if only it weighed ohh say 200kg's less. AFGMoto I missed you setup (coils,sways etc.) what is it?

afgmoto1978

iTrader: (6)

The wheels are Volk RE30s - 18X8.5 +40 and 18X9.5 +40

Eggie

Good job, Adam. Bet you could go even faster without that "exhaust restrictor."

afgmoto1978

iTrader: (6)

Hehe, actually if I had DTC70 pads on I could have easily shaved off another second to my time.

dradon03

iTrader: (2)

I should have been a better reader on that one. It is nice to see that with a relatively "basic" setup with good guidance and knowledge that the FD is still capable of taking it to newer cars, even though my car is very difference I hope to do the same when mine comes toghether.

Were you pushing even close to as much power as the Skyline?

afgmoto1978

iTrader: (6)

400 whp vs ~500+ whp

afgmoto1978

iTrader: (6)

Here are some pictures of me going through turn 4 - 5 complex. And me going off for the last time that day, hehe.

dradon03

iTrader: (2)

Your shocks don't bottom out at that ride height? They look lower than 25in RH but maybe it is because you are in compression. Maybe it is because of my 255/40/17's that look really different on the car.

The RE-1R's have a symetrical design correct? Is that why you were less than aggressive on the rear camber?

afgmoto1978

iTrader: (6)

Nope, the rear is set at 25" from the ground to fender. I think - 1.86 Deg is rather aggressive, at least for street tires. Actually, like Howard wrote earlier, less rear camber may be in order with these street tires. R-compounds would be a different story though.

The next event for me may be an asphalt hill climb, the way the road is layed out with both on and off camber corners, I'm thinking 0.5 deg less rear camber, even with my 710 tires....

dradon03

iTrader: (2)

I just read this

"Rear:

-1.25 Deg Camber"

That is why I was asking.

afgmoto1978

iTrader: (6)

Okay, no worries.

Andrew.

iTrader: (4)

Congrats afgmoto1978!

Alright, after reading through it again and going through my 10 pages of notes from this thread, I have a few questions:

1. Is there a significant advantage on running the same tire size all around vs. a setup with a smaller front tire? . Let's say a 275 all around setup vs. a 255/275 setup. It's getting annoying trying to find a set of decent wheels in the same size all around. I'm thinking of just getting some 17x8/17x9's and running 225/275 R888's for my track tire setup.

2. What do you have to say about dampening and adjustment on shocks (how many clicks)? Should I just do the zip-tie method and aim for less than 1.2" of travel on the shock on each corner and dampen accordingly?

3. Can you PLEASE shoot some in-car video when you get on the track?

Thanks HC!

afgmoto1978

iTrader: (6)

Video of my first qualifying session. Note, I was sloppy as fu'K on my line, braking points, etc. A few close calls.

In my defense it was my first time out in 2.5 years were I've driven this car at 10/10, so I was feeling out what the limits were (yeah, something like that ). I cleaned up my line and braking points considerably once I got to the point of doing my fastest lap during the main. Hopefully they post that video up as well.

http://my.drivingsports.com/kickapps...758/45077.html

Howard Coleman

iTrader: (6)

which end of your car was doing the squealing?

afgmoto1978

iTrader: (6)

Mostly front, it was mostly due to my corner entry speed and line. During my fastest recorded lap, tire squeal was very minimal.

Note, I found out after the event that the shocks self adjusted themselves to the softest settings. I need to get a replacement EDFC controller. The one I had died on me before the event. Seems like a recuring problem from what I hear from my friend's who have them as well.

habu2

My Tanabe swaybars are on the way. Now I need....

Has anyone heard from David Breslau / Widefoot Racing lately? I've tried emailing him at widefoot at comcast dot net and PM-ing him via the forum, but I haven't gotten a reply. I see he hasn't posted to the forum since May...

gracer7-rx7

iTrader: (16)

^I spoke with him in early July. That is the correct email. Send him another email in case yours went to spam. He might also be on vacation. Tis the season....