BAustin's Extended Track - 06 SS/SC Donor - #157 Registered

[baustin]

Overall a neat day at autocross yesterday, was on the "Little Rock" track outside the main Rockingham Speedway.

From folks that do autocross a lot, there wasn't a lot of grip on the track. Surprisingly the banking wasn't too weird for me. Unfortunately I did end up spinning out on my first run... again... across the finish line. At least this time I didn't hit the cones at the finish, only after the finish. Whether that 1st run should be a DNF for taking out 3+ cones after the finish didn't matter since my 4th run was only .002 slower. Ended up that my 1st run was my fastest, when I tried to push harder on the 5th run I ended up sliding on the inner loop and being .2 slower, I figure I lost at least .5 from that slide. I'm not good enough yet to know if my tires really have any more capability but I didn't really feel like I had any more grip in the later runs or which direction I should adjust my shocks. I'm sure a lot of it has to do with smoothness on the inputs which isn't my strong suit so far, hence my spins at the finish. I'd rather learn my car better before replacing the tires though I will be replacing them at some point this year since my initial alignment badly wore the front tires (currently on the rear). I'll need to look into what type of tires I want but am kind of surprised at the current pricing, the tires I bought in 2019 are now 40% more expensive, they used to be on the cheap end.

Run #1

Run #2
--forgot to record this one, had an instructor riding along--

Run #3

Run #4

Run #5

During tech inspection, they noticed a slight clunk when pushing/pulling on the front wheels. They still let me run but where wondering if it was the bearings. I took a closer look back home and it seems that it's the heim joint sphere inside of the bushing. The portion I'm pointing at in the picuter. With a finger tip on the sphere, you can feel it move relative to the eye bolt portion (not sure of the correct names here). The bushing isn't moving, just the sphere. It's not a slip of the upright bolt within the sphere, and it's not the threaded end of the heim joint to the control arm. I don't see any correlation between the distance threaded out and this clunk, the lock nut has remained solidly tight and any wear on the bushing should be independent of the threaded length, after 2 autocross events with 2 full spins I feel comfortable with the engaged length on a car this light. I feel a very similar movement on the driver side, maybe just slightly less clunk sound though. I don't feel any clunk from the lower heim joint, either driver or passenger. You can feel the clunk through the upper control arm when pushing/pulling on the wheels (makes sense with it all being bolted together), and nothing on the lower control arm. Not sure if I should order some replacements for these upper heim joints or if this is typical for heim joints. Maybe others can confirm if pushing on the top of the wheel produces a slight clunk/movement from within the upper heim joint?

My upper heim joints can swap sides (top passenger <-> top driver and bottom passenger <-> bottom driver) but my lower heim joints are left hand thread instead of right hand, so I can't swap top to bottom. I probably should just buy 2 of the right hand thread type to have ready to swap in.

 

[Rttoys]

Have you tried to tighten the through bolt? Mine was making a similar noise after a few autocross and figured it was a little loose. Gave it a little extra tightening and all noises stopped. Those heims are pretty stout. Wouldn’t think you have a problem with one.

 

[Rttoys]

That bank would be hard to get use too.

and you need better tires.

 

[baustin]

Have you tried to tighten the through bolt? Mine was making a similar noise after a few autocross and figured it was a little loose. Gave it a little extra tightening and all noises stopped. Those heims are pretty stout. Wouldn’t think you have a problem with one.

I'll double check the through bolt torque, maybe the tightness deforms the sphere a little so it's a tighter fit in the bushing.

 

[JBINTX]

Overall a neat day at autocross yesterday, was on the "Little Rock" track outside the main Rockingham Speedway.View attachment 32235

View attachment 32236

View attachment 32238

From folks that do autocross a lot, there wasn't a lot of grip on the track. Surprisingly the banking wasn't too weird for me. Unfortunately I did end up spinning out on my first run... again... across the finish line. At least this time I didn't hit the cones at the finish, only after the finish. Whether that 1st run should be a DNF for taking out 3+ cones after the finish didn't matter since my 4th run was only .002 slower. Ended up that my 1st run was my fastest, when I tried to push harder on the 5th run I ended up sliding on the inner loop and being .2 slower, I figure I lost at least .5 from that slide. I'm not good enough yet to know if my tires really have any more capability but I didn't really feel like I had any more grip in the later runs or which direction I should adjust my shocks. I'm sure a lot of it has to do with smoothness on the inputs which isn't my strong suit so far, hence my spins at the finish. I'd rather learn my car better before replacing the tires though I will be replacing them at some point this year since my initial alignment badly wore the front tires (currently on the rear). I'll need to look into what type of tires I want but am kind of surprised at the current pricing, the tires I bought in 2019 are now 40% more expensive, they used to be on the cheap end.

Run #1

Run #2
--forgot to record this one, had an instructor riding along--

Run #3

Run #4

Run #5

During tech inspection, they noticed a slight clunk when pushing/pulling on the front wheels. They still let me run but where wondering if it was the bearings. I took a closer look back home and it seems that it's the heim joint sphere inside of the bushing. The portion I'm pointing at in the picuter. With a finger tip on the sphere, you can feel it move relative to the eye bolt portion (not sure of the correct names here). The bushing isn't moving, just the sphere. It's not a slip of the upright bolt within the sphere, and it's not the threaded end of the heim joint to the control arm. I don't see any correlation between the distance threaded out and this clunk, the lock nut has remained solidly tight and any wear on the bushing should be independent of the threaded length, after 2 autocross events with 2 full spins I feel comfortable with the engaged length on a car this light. I feel a very similar movement on the driver side, maybe just slightly less clunk sound though. I don't feel any clunk from the lower heim joint, either driver or passenger. You can feel the clunk through the upper control arm when pushing/pulling on the wheels (makes sense with it all being bolted together), and nothing on the lower control arm. Not sure if I should order some replacements for these upper heim joints or if this is typical for heim joints. Maybe others can confirm if pushing on the top of the wheel produces a slight clunk/movement from within the upper heim joint?

View attachment 32237

My upper heim joints can swap sides (top passenger <-> top driver and bottom passenger <-> bottom driver) but my lower heim joints are left hand thread instead of right hand, so I can't swap top to bottom. I probably should just buy 2 of the right hand thread type to have ready to swap in.

Interesting track with the banked portions.
You had some tire squeal in a few of the turns that surprised me. A set of stickier tires will make the car feel amazing.

 

[baustin]

Oh, I only realized when I was watching the videos yesterday evening that I had an annoying rattle from the GoPro frame against the windshield, whoops. Should've tilted just a bit back from the windshield.

 

[Brett]

I think you are leaving alot on the table with your current tires. Looking through your build log, it looks like they are General G-Max RS in a 225 width.

Those tires are a 360 Treadwear tire. If I were replacing them, I would should for sub 200 TW. Preferable 100TW.

These cars are so light, that even 100TW tires should last awhile. How long, I don't know but I wouldn't be surprised if I get 5000 miles out of mine.

 

[baustin]

I think you are leaving alot on the table with your current tires. Looking through your build log, it looks like they are General G-Max RS in a 225 width.

Those tires are a 360 Treadwear tire. If I were replacing them, I would should for sub 200 TW. Preferable 100TW.

These cars are so light, that even 100TW tires should last awhile. How long, I don't know but I wouldn't be surprised if I get 5000 miles out of mine.

Yeah, I'm sure you're right about the tires leaving a lot. You named the ones I have. They are 360 TW but remember that's a brand relative number, it's not 100% relatable across brands.

I went with those first since they were cheap at the time and still have really good rain siping. Any damage done from bad alignments would happen on these and I'd be better at setting up the car when I put nicer tires on. The current front tires have more than enough tread left, the current rear tires got chewed up from unintentional toe out when on the front and are basically at the wear bars on the inner edges. To pass yearly inspection I'll need new tires for sure after I put more wear on this year. But I think it's good to start learning the characteristics of the car with these tires so I'll actually know how much better the new set will be. These have a lower grip limit which cause me to slid/spin easier at autocross but it prevents me from breaking more things (steering arms, lower rod end mounting brackets, etc that others have thoroughly tested). I do have those upgraded bits installed, still need to install the rear control arm spherical bushings.

I don't plan on having 2 sets of tires because of autocross, just 1 set. I'll still want to have tires that can manage some wet roads occasionally because I do plan on driving it a lot and some miles will be wet but not too many. Sometime soon I'll look through other build logs to see if there's a tire I want to copy. Not sure I plan on going wider since that requires new wheels too, for now.

 

[baustin]

While wiggling the front wheels confirming the clunk at the front was actually the heim joints, which it definitely seems to be, I noticed a jingling sounds coming from the engine area. I checked all around and found the jingle was the washer on the lower bolt to the transmission from the front solid mount... the upper bolt was nowhere to be seen and the lower was halfway out... yay. There were circle marks where the washers had been clamping the bracket so I know I had definitely torqued them down after finishing the paint on the bracket and installing it.

*this is an old pic copied from when I first was installing the transmission mount, X bolt was entirely missing, circled bolt was halfway backed out*

I guess I'll be buying a pair of new grade 10.9 M12x35mm bolts with M12 washers tomorrow. The one that I did find could be threaded out by hand and definitely has the thread peaks flattened slightly so it's a throwaway bolt now.

I don't know what torque spec I used previously since it was a while ago but I assume it was in the range listed below. I think these 2 bolts are the 'M12 solid mounts to transmission' and should only be 44ft-lbs since they go into threaded aluminum of the transmission.

snip of Adam's installation guide link here

There's no locking feature with the bolt or flat washer, I want to use some sort of locker so I would lean towards a liquid thread locker but not sure about it being the aluminum case of the transmission. I do have the blue type in my garage already. Any thoughts on what locking method I should use to prevent these from loosening again?

 

[Ross]

Blue liquid thread locker will work well in aluminum. Also will prevent corrosion/thread galling.
Otherwise you can use thread anti seize with a lock washer. Both methods work.

 

[Desert Sasqwatch]

Or lengthen the bolt by 5mm and double nut (lock nut) the bolts. Oops, thought these were though bolts - nevermind!

 

[baustin]

Blue liquid thread locker will work well in aluminum. Also will prevent corrosion/thread galling.
Otherwise you can use thread anti seize with a lock washer. Both methods work.

Yeah I'll probably do the blue thread locker. Lock washers is a subject I don't want to dive into, mechanical engineer here and I work in the electrical design world where lock washers are a real pain even when done correctly. I really don't want to dive into lock washers... I think that's even been brought up on this forum, always is a topic that is very intricate.

Or lengthen the bolt by 5mm and double nut (lock nut) the bolts. Oops, thought these were though bolts - nevermind!

Ha, yeah. No problem, it's soooo much easier to ensure lock if it's a thru hole.

 

[Rttoys]

I'll double check the through bolt torque, maybe the tightness deforms the sphere a little so it's a tighter fit in the bushing.

Maybe. Never know. Everything moves a little until settled in.

 

[Rttoys]

I don't plan on having 2 sets of tires because of autocross, just 1 set. I'll still want to have tires that can manage some wet roads occasionally because I do plan on driving it a lot and some miles will be wet but not too many. Sometime soon I'll look through other build logs to see if there's a tire I want to copy. Not sure I plan on going wider since that requires new wheels too, for now.

That’s why I went with the R888R’s on mine. Great for autocross, but road worthy. They also squeal and squeal and squeal, but still grip, not just let loose like less sticky tires. My old tires (BFG something something) would barely squeal and bam…….spin out. Goose the gas and spin out. With the r888r I can control the skids very well. Tire pressure is key though.

 

[ccannx]

There were some folks that knew a little about Goblins, I think @ccannx may have run with THSCC at Danville sometime in the past so some may have seen one before. The folks I talked with really liked it. I wasn't anywhere close to the fastest for the RAW times. I haven't dealt with PAX times before but they don't seem to apply to novices very well, probably better for veterans that can truly push their car to the car's limits. My best time (4th run since 5th run had a cone +2 sec penalty) was good for 25th (PAX scoring, fastest novice was 2.2 seconds faster than me excluding cones) in the novice category. 110 drivers there for this autocross.

results link



My goal for the day was to have fun and maybe push the car hard and get better near it's limits, I was successful with those goals. Spinning across the finish acutally helped me know where the limit of too much actually was, it was learning through mistakes. My instructor told me to dial back the agression a bit after the first run, I think I had him pretty worried after I was describing that I would try to take it easy... I tend to overdo my first attempt at things, ie swing the hammer too hard and break things without meaning too. After the 2nd run he wanted me to add the aggression back in, a little bit at a time.

The Goblin can easily take a TTOD spot, last PCA event I went to It was 4 seconds faster than anything else that showed up that day. But the Thscc guys are faster than the PCA guys

Your tires are killing you. If you can run stickeis call up JB racing tires and get a set of used takeoffs or buy one of the autcross tires rt660,bfg Rival, A052 Yokes if you street drive .If your on the stock steering arms you can toe the front and rear In and maybe tame some of the snap oversteer out. Your spring rates are probably fine. E-mod people always tell me to go stiffer. The Goblin is too rear end loose to run much of a stiffer spring and any stiffer in the front and you won't have any static rebound IMO. A double adjustable up front and you can up your compression so the front doesn't dive during braking will net you more grip than going to a higher spring rate for autocross. Track I have no idea.

I haven't been autocrossing mine much because I blew my motor then rebuilt with a b207r + EFR turbo and have since been building a 79 corvette for CAM-s class

 

[baustin]

The Goblin can easily take a TTOD spot, last PCA event I went to It was 4 seconds faster than anything else that showed up that day. But the Thscc guys are faster than the PCA guys

Your tires are killing you. If you can run stickeis call up JB racing tires and get a set of used takeoffs or buy one of the autcross tires rt660,bfg Rival, A052 Yokes if you street drive .If your on the stock steering arms you can toe the front and rear In and maybe tame some of the snap oversteer out. Your spring rates are probably fine. E-mod people always tell me to go stiffer. The Goblin is too rear end loose to run much of a stiffer spring and any stiffer in the front and you won't have any static rebound IMO. A double adjustable up front and you can up your compression so the front doesn't dive during braking will net you more grip than going to a higher spring rate for autocross. Track I have no idea.

I haven't been autocrossing mine much because I blew my motor then rebuilt with a b207r + EFR turbo and have since been building a 79 corvette for CAM-s class

Really good info/feedback, thanks. I think my cousin that lives near Chester, VA knows of your car and has ridden (or did he say driven?) your car before. He runs his mustang in a bunch of autocross events in the Virginia area.

I'll be sticking with streetable tires for now, I use mine more like a fair weather motorcycle to/from work, kid's school sometimes, or other fun drives. And now at least a couple autocross events.

I'm also signed up for the next THSCC autocross event at Southern National motorsports park near Wilson, NC.

 

[baustin]

I've got a new set of tires shipping to my house and will get them installed very soon. I decided on trying the 225/45R17 Kumho V730 (tire rack link). These are replacing 225/45R17 General G-Max RS (tire rack link) tires I've had on since fall of 2019. I had really nice grip initially with the G-Max RS tires but throughout 2022 they have become very hard and just don't have the grip level they once had, especially obvious in the couple autocross events I did earlier this year. One thing that didn't help the G-Max RS tires is their age: I bought them fall of 2019 but Discount Tire Direct shipped me 4 tires manufactured during spring 2017 (2nd attempt at shipping after the 1st set they shipped got labeled wrong and went to someone else).

Tire rack current pricing is $163.80 each, +$15 each for heat cycling before they ship, + tax/fees. Total to my door is $776.56, not mounted/balanced. I'll still need to go by a tire shop to get them mounted/balanced.

While I partially wanted to try a set of A052, they are far more expensive currently $238 each before all other costs. The RT660 was also on my short list and are nearly the same price as the V730 at $168 each.

 

[Rauq]

I'm always curious to get the perspectives of folks with similar, but not the same, choices as mine.

What draws you to the A052? And what led you to the V730 over the RT660? I'm running the RT615K+ in the same size and like them. I chewed up my fronts with bent lower rod end mounts (since replaced and realigned) and thought about replacing with the RS4 but decided to stick with the RT615K+ as my rears were still good and wanted to match. Thanks for your input!

 

[Desert Sasqwatch]

$60 for heat cycling?!? Heck, I can put a set of tires in the driveway under a tarp for a few hours and they are heat cycled out here in Phoenix!

 

[baustin]

$60 for heat cycling?!? Heck, I can put a set of tires in the driveway under a tarp for a few hours and they are heat cycled out here in Phoenix!

Ha, I'll gladly avoid the Phoenix heat if it means I should pay someone else to heat cycle the tires! I know I have a <2% chance of properly heat cycling the tires myself given my experience, I'm hoping the correct heat cycling will let the rubber last for enough years to wear out the tread this time.