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It was pretty shocking racing my bone stock 2010 Grand Sport after getting out of the significantly modified Formula. The vette was on junk tires and I'd barely driven it and my times were as fast or faster than they were in the bird on new 315 AR1's. I'm not getting rid of the bird, but there's something to be said for starting with a better platform...
True, and those platforms are certainly more confidence inspiring right out of the box, but that's reflected in the upfront cost. I do have a couple more avenues to explore before moving on and most of them center around getting more confidence/grip out of the rear of the car.Quote:
Originally Posted by rentedmule
-Lower roll center in the rear with stiffer springs for less lift under braking, but similar roll stiffness
-Watts link for less mid-corner disruptions
-Mild aero up front to neutralize any lift that might be happening
-Decoupled TA (if I can find one?) to use the live axle to its advantage by having more antisquat on corner exit
If I can't shit on a competent driver in an SS1LE with all that and good tires, then it's vette time lol.
Also, I built the spoiler after seeing this vid. This is the same guy who set the f-body nurburgring record all those years ago. Interesting that slapping a spoiler on the bird made it more planted on corner exit than his C5z.
https://www.youtube.com/watch?v=3IxN7GAhh7o
I've watched that guy's ring videos many, many times - so much fun.
I bet the Watts would help a lot. Mine is still laying on a bench. I had the best intentions of getting it in for this season but no luck. From your videos, it doesn't look like you're struggling for control on corners but maybe it would just smooth things out to give you more speed?
I find one of the biggest differences with the vette is the ability to put down power, even from a dead stop. I know a lot of that is a well-tuned IRS, but I never felt the Formula launched or pulled out of a corner like it should with huge r-compounds. Are you running drop LCA brackets in the rear? I have some sitting on the bench beside the Watts link...
So I remember the ring guy renting a e92 M3 on tire at the end of his stay in Germany and running within a couple seconds of his Firebird. The chassis can't be that bad lol.Quote:
Originally Posted by rentedmule
I don't think the watts is going to help me at all with mid-corner grip, but it should certainly prevent the car from getting upset during transitions (due to lowering the rear RC) and over quick transients (due geometry/range of motion). I think the former will have a larger affect on lap times than the latter, but the watts kills 2 birds with 1 stone compared to a lowered panhard setup.
I never found that I had issues with putting down power in the car except for when the posi was dying or when the LCAs were sticking. Actually quite the opposite, I've always felt like the car squats like a drag car and rockets out of corners wayyyy sooner than I think it can. The rear is somewhat softly sprung so the sensation is a little unsettling at higher speeds because there is so much motion, but it usually works out. No LCA relocation brackets or anything and my TA is stock length.
My biggest gripe with the current setup is that it has always felt super loose and unsettled at the rear during hard braking/corner entry, almost as if the back of the car wants to do a stoppie like a motorcycle and rotate around. The soft springs are definitely contributing to the issue, but upping with spring rate in the rear without dropping the RC seems to make the car edgy and hard to recover once the rear lets go because of the added roll stiffness. I think the general balance of roll stiffness front/rear is good as-is, but the roll axis inclination from the rear RC being so much higher than the front means the rear end has to be floppy fore/aft to preserve roll balance. This arrangement was intentional by GM in order to get better ride quality out of a live axle car, but it completely screws me on the track, especially anywhere I'm required to brake/turn at the same time. The best example of this was T1 at Palmer where I couldn't dive into the corner nearly as deep or with as much speed as everyone else because there were too many overlapping elements.
I'm running BMR springs and they're softer than Stranos. I got them used/cheap before I had any intention of racing the car.
I think you described the characteristics of my car too - I'm probably just driving around that handling flaw but I trail-brake a lot to get it to rotate on the tight auto-X courses we run here. Between that and lift-off oversteer, I often end up drifting when I'm really pushing it.
Is that issue why so many of the FRRAX guys run crazy stiff (1000#) springs?
Do you know when the BMRs are from? I know they revised them at some point and basically made Strano knockoffs at 550/160lb (the SP001R set). I wouldn't be surprised if they were the same springs from the same factory with different marketing, but someone would need to measure the wire diameters and coil OD of each to be sure. The # of active coils looks identical.Quote:
Originally Posted by rentedmule
http://www.stranoparts.com/data/images/p1930153026.jpg
https://m.media-amazon.com/images/I/...AC_SL1500_.jpg
I'm actually running the standard BMR 160lb rears but with Eibach 850lb fronts on my coilovers. Front rate may seem high, but the factory style shocks don't have a lot of travel before hitting their foam bumpstops which effectively makes the wheel rate progressive. Sam told me 800-850lb springs on a high travel coilover are similarly balanced to 550-600 on a stock style shock.
I also see a lot of different rates thrown around on FRRAX, but some of them are from 3rd gen people or those running slicks so it's apples to oranges.
Do you have the stock posi? I would get lift off oversteer when mine was dying or if I had way too much LSD additive in the diff. It would make the car step out during quick transitions while on throttle too. The sensation was really strange because you could feel the rear moving around and taking a wider line without the tires screeching like in a slide.
Also, how thick of a rear sway bar are you running? I am only running a 21mm solid 3rd gen bar and found that the "23mm" (actually 22.3mm or 7/8") solid Addco bar made the car very squirrely. It seems like the sway bar does more work to combat roll than the springs themselves on the rear at least. Just a change from 21mm to 22.3mm took the bar rate from 210lb/in to 260lb/in if these calculators are correct. The arms are 8.5" long and the center section is about 32" if I remember correctly.
https://www.gtsparkplugs.com/Sway-Bar-Calculator.html
I installed the BMRs in 2015 and I'm not sure how long before that they were purchased. I know the old version of them was in the ballpark of the Stranos, so it was never a priority to change them.
I'm running the non-adjustable Strano hollow sway bars 35 front and 22 rear with Koni yellows all around.
I do have the stock diff as far as I know, but I have no history on the first 170k kms of the car so it could be aftermarket. I had a shop change the fluid at some point when I installed the diff cover and they made a point to mention that it looked brand new. I think I'm ok on quick transitions and putting power down on sustained turns but I'll pay attention to that the next time I run it. It'll definitely spin both consistently on a launch.
Good info on the spring rates with/without bumpstops. In all the discussion I've seen on FRRAX, I don't think I've ever seen that mentioned.
I had no idea about the stops until Mr. Strano was talking me into higher rate springs.
Before I bought the Ridetech fronts, I decided to cut open the dust cover on one of my Bilstein HDs while it was installed on the car with UMI lowering springs. There's maybe 1/2" of travel before the yellow shock body hits the orange foam stop with the car on level ground. The motion ratio allows the wheel to move a little more before contact, but the travel still sucks. The car rode 10000% better with the Ridetechs just because I wasn't hammering the hard foam stops all the time.
Attachment 40526
Interesting - I've always felt like the car was just too low to ride well but that probably explains it.
This reminded me that I have a set of Eibach springs NIB. They came with my Camaro when I bought it.
EIBACH PRO-KIT 3831.140 They are lowering springs I think about 1 1/2".
They can be had cheap, if any of ya'll are interested in them.
Nolan
So the spoiler definitely works! I tested it at NJMP Lightning earlier in the week. The effect is subtle, but the car certainly feels more planted in the rear at higher speed, especially when on throttle. This is the most noticeable on turn 5 (blind right-hander over the hill) and turns 9+10 (final turn before the straight). I feel like I can floor it much sooner without things getting twitchy. No noticeable understeer and the balance feels perfect.
I also finally cracked last year's PB by a little and ran a 1:16.145. The rear spoiler, -50lb weight reduction, +0.5 camber, and cooler weather made it easy peasy as I was turning 16s and 17s consistently on all 3 sessions. My lap timer is showing me some theoreticals in the high 15s with decent confidence so I'll have to work on that.
I got to chase around a couple neat cars as well...
https://www.youtube.com/watch?v=KMa302pPvLo
Really debating switching my tires to 295/30R18 RE71-RS and unloading the RS4s over the winter as they're the biggest thing holding me back. This would net me about another 0.2" of rubber on the road at each corner, plus the compound is wayyyy stickier. I'm thinking it would be worth somewhere around 1.5s easily. I'll be able to annoy SS1LE and Porsche owners more effectively.
Tow rig+trailer+Hoosier R7's FTW!
I absolutely demolished my PB at Thunderbolt over the weekend with a 1:33.44 which is about 2.3s faster than the memorial day event. I would say 80% of the gains are from the extra confidence the spoiler gives me around fast corners like T3 and T12 (little bit of T6 too). The back end feels so much more planted and I'm able to carry way more speed than I'm used to.
https://www.youtube.com/watch?v=ZnDm2QGkm-w
Also had a really good chase with a modded C5 Z06 on 315 RT615K+ tires. He was a smidge faster, but we were running at a similar pace.
I might end up parking the car for the season though because I am noticing oil pressure woes in a couple turns (right-handers after hard braking). Maybe I am underfilled at 7qts? This dipstick also sucks and it's hard to tell how much oil is in the damn thing at any given time. Gonna drain the oil and look for more specs, then decide if doing The Glen or Pitt is worth it.
Accusump it to limp thru?
i just sold brian (caprice guy) a moroso trap door pan lolQuote:
Originally Posted by Catmaigne
laps looked cool, liked your insta post talking to the car lol
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That's probably what I'm gonna have to rig up as a temporary solution.Quote:
Originally Posted by shownomercy
Edit: Holy crap, these things are expensive....
They're a pain to set up as well, although maybe easier for something that's mostly a track car. I had one ready to go onto the truck I raced a few years ago - after reading many threads about reliability issues, I decided to pass on it.
I'm gonna try to approximate the amount of oil in the filter, lines, and cooler to see if I'm undefilled or not at 7qts
Couple things I could do:
1. Extend the partitions upward
2. Better windage tray (it's stock)
3. Try a pump pickup tube with a smaller opening
or as a last resort...
4. Relocate the oil filter and run a pan with a larger driver side kickout
Pics of what's on the car atm:
Attachment 40527Attachment 40528
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Awesome driving, you're looking like a seasoned pro behind the wheel(I like the new one). Thanks for sharing these well put together videos, they are fun to watch.
My opinion fwiw is the in-car camera is better than the helmet cam. Hope the DEVIL car engine holds up for more track time for you. Still amazing how many cars you're spanking with an old antique LT1. LOL
Nolan
Sorry for the thread hi-jack but I thought you might be interested that I got a Nascar driving experience for my birthday. My marvelous wife bought me a package at Talladega with 8 minutes track time. Should have gotten 4-5 laps with top speed RPM(5000) limited to 150 MPH. I only got a lap and a half due to a wreck in turn 3. They were running over the alotted time and had to give the track back to Nascar. Sooo, I got up to 4900RPM which might have been 140mph. It was fun and now I have some seat time and know what to expect. This ain't like driving a F-Body around there, it's a full-on race car and you really have to drive it. Acceleration and g-force is pin yo ass in the seat awesome.
Due to the circumstances they gave me a coupon so I can do it again.
Nolan
I'm on the bottom;
https://www.youtube.com/shorts/g1ducCizPhE
Last track day of the season, this time at a new track (Pitt Race). Weather was garbage and all of the sessions were super slippery except this one from late afternoon Saturday.
Best was a 2:03.39 which is decent, but I know this car has a ton more in it. I really need more time in dry conditions to figure out how deep I can brake and what curbs I can hop.
Here's a chase with a modded e90 M3. He's got RE71RS tires, Fortune Auto 510 coilovers, catless exhaust, brakes, etc. It was also his first time at Pitt and he had similar track experience to me or more.
https://www.youtube.com/watch?v=MSnqkEDEKEY
Also, my wideband went to shit and one of the seat studs pulled out of the floor over the weekend, good lord.
That track looks fun! Too bad about the seat stud. I put a fixed back Momo seat in mine at one point and used no-name single locking sliders - they let go on the first hard corner of a regional auto-X event. It's really hard to drive when the seat moves...
You were nearly on the same pace as the Beamer, seems like he was only pulling away on the straights. I had to look it up, but he has 420hp at 8300! You could hear it screaming when he wound it out. Thanks for sharing the videos, they are great and best of luck on next year's season.
Nolan
I noticed I still have occasional oil starvation issues, usually after hard braking into a tight right turn. I dumped even more oil into the pan before Pitt (8 quarts total), but the issue is still there.
I think I figured it out though. This Kevko pan has 3 trap doors (red arrows) and a baffle box around the pickup, but there are no other walls outside of the pickup area to control oil flow. I think adding 2 walls at the baffle box corners (yellow lines), it will force oil into the pickup area instead of allowing it to travel around to the other side.
I also would like to add a longer/curved windage tray.
Thoughts? Attachment 40536
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Look into 4-way trap door baffling in the sump. I had a similar issue on a SBC boat engine during spirited high speed driving. I found an economy circle track pan with kickouts and 4-way trap doors. It absolutely cured the problem. You could probably buy the parts and weld them into your pan. Here is an example of how the 4-way trap doors work.https://www.youtube.com/watch?app=desktop&v=8eapLmnkErQ
Nolan
I'm unsure how you'd do a 4-way baffle in a SBC because of how low and far back the oil pump and pickup sit. My 3-way is probably fine for a road course car that doesn't accelerate with that much force. It would be a different story if I had 600whp lol.Quote:
Originally Posted by JOATMON
I still think what I really need is partitions. Notice that the Improved Racing baffle has 1 door per outer partition and they all feed the pickup at the center. I need to create something similar in mine.
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I shipped Lloyd some heads for LE2 treatment and an intake manifold to match. They will ultimately end up on a 355 with a lazy Lunati 219/227 cam that should be happy to tach up to 6400 all day long. That motor is going to be a longer term project though, so hopefully my current one stays together long enough.
I was going to blow a bunch of money on Apex 18x11" wheels and RE71RS tires over Black Friday, but decided to invest in safety instead since the car is already too quick for its age. Picked up 2x G-Force FIA 6pt endurance style harnesses and a Necksgen neck restraint. I also got a decent MIG welder, new helmet, cart, gloves, jacket, blanket, and cylinder so I can install my S&W 4pt rollbar. I have MIG welded a number of times before and also own a garbage HFT flux welder, but I will need lots of practice before installing anything. I might end up paying my buddy who has much more experience to come to my house and burn it in if I don't feel confident after a while.
Attachment 40537
Attachment 40538
These showed up from Lloyd, that was fast lol.
Attachment 40539
Attachment 40540
That was unpleasant...
Currently chopping up the HVAC box to fully delete AC but keep heat. I also pulled the passenger airbag out.
Attachment 40541
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WOW, Looks like its going on a serious weight reduction diet.
couldve done it from under hood lolQuote:
Originally Posted by Catmaigne
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Dash was already coming out to get the airbag, insulation, etc. Doing it from the bay really sucks anyway lol.Quote:
Originally Posted by SSlowBoat
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fair, it did suck lolQuote:
Originally Posted by Catmaigne
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Seems like Fred said that when he was removing weight from the resurrection Firebird he even took the windshield wipers off. LOL
they are still on there lol, my car weighs 3820 with me a full n2o bottle and a half tankQuote:
Originally Posted by JOATMON
Wait, Maybe it was the sun visors. LOL
What was it Fred?
3800 lbs is higher than I thought for a 4th gen F body. But I wouldn't know because I've never weighed my Camaro. So thanks for that info.
its heavy as hell, and yes sun visors were removed by fred lol.Quote:
Originally Posted by JOATMON
most of these cars are around 3300-3400lb
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Why do you think it's so heavy? Do you still have a lot of creature comforts like AC and most of the interior intact? The formy bird should be one of the lightest around 3350lbs stock in basic trim and hardtop, but I think a more optioned t-top would be closer to 3450.Quote:
Originally Posted by SSlowBoat
Hoping mine will be around 3300 w/o me, but that might be optimistic. Off the top of my head...
Weight taken out: no AC/emissions/airbags/ABS components, all heat shields tossed, no rear seats or belts, Grant wheel, tiny Odyssey battery, fixed back seats, no sound insulation or firewall insulation, T/A hatch (not much considering my spoiler), lighter stereo (only 2 speakers and a tiny aftermarket head unit), LTs and lighter muffler, marginally lighter hood, 1 sun visor, aluminum flywheel and driveshaft, cut HVAC box, hollow Hellwig sway bar, coverlay as a dash pad lol, hopefully some lighter carpet in the future?
Weight added: Triangulated subframe connectors (Kenny Browns, although they seem way lighter than others), CTSV brakes and 14" rotors, wheel hubs, rear LCAs, oil and PS coolers, preloaded diff cover, torque arm, RR oil pan, tow hooks, future 4pt cage/harnesses/fire extinguisher and brake ducts
Potentially lighter stuff: Ridetech coilovers up front
I also bought a spot weld cutter and am gonna remove a bunch of brackets in the rear half of the interior.
think? i weighed it on a certified scale LMAO have the printout in the car. subtract 24lbs for a nitrous bottle and 225lbs for me, its still heavy. no ac at all, turbo 400, chromoly cage, 12 bolt, chromoly rear suspension stuff, gear vendors, stock k and front arms, stock brakes, t-tops, no rear seat or stereo, but etc etc so 3571lbs without me or a nitrous bottlleQuote:
Originally Posted by Catmaigne
i have gutting and cutting still to do. you should be able to get lighter than 3300lbs. most on the drag side are 3100-3200lbs
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