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Steve91T
That’s what the fastest Vette in my class beat me by. My goal in life is to be faster than those guys.

I already posted this video, but for reference, here it is again. The lap timer was lagging for some reason, but you get the idea.


https://youtu.be/CUAtHvo7mTo


My LSD is completely shot. I’m losing tons of time out of right handers. I have to manage the right rear wheel spin until the wheel is damn near straight then I can get on the gas. I’d be willing to bet I’m loosing a full 2-3 seconds just from that alone. Then there are the brakes. I have to be very careful and can’t get on them hard because of axle hop. Once I install the bias controller, I’ll be able to get on the brakes much harder and sooner after jumping off the gas. I’m thinking maybe another full second a lap there.

So with those two things, that’s already 3-4 seconds. What’s cool is I’m under power and over weight and even then, I’ll be in the upper 1:40’s. That’s a very respectable time. Even right now, people were surprised that I’m in the low 1:50’s.

More power will come when I swap an LS1 along with 120lbs of lightness between engine and transmission and UMI crossmember.

What are your thoughts on Lexan rear glass? Worth the price?

I’m also thinking about stepping up to 18’s and running a 295 tire, the widest NT01. Maybe someday they’ll make a 315.

I’ve read a lot about Shocks. Mine are adjustable Koni fronts and Sams revalved rears. I’m thinking UMI’s shock package would probably help, but I’m not sure.

What else?

Front aero?

Remember the car needs to stay street legal.

With the brake bias fixed and a working LSD, I would have been faster than the majority of the cars there. That’s pretty exciting. With some more work, it’ll be track monster.

Thanks guys!

https://flic.kr/p/ZtGV53
79T/A
Regarding the NT01, they do not make a 295. Nitto makes a 305/35/18, a 315/30/18, and a 335/30/18. Not nearly as fast as a Hoosier, but they are very durable. Definitely softer side walls than Hoosiers.
Steve91T
QUOTE (79T/A @ Nov 15 2017, 01:37 PM) *
Regarding the NT01, they do not make a 295. Nitto makes a 305/35/18, a 315/30/18, and a 335/30/18. Not nearly as fast as a Hoosier, but they are very durable. Definitely softer side walls than Hoosiers.



You’re right, I’m not sure where I got that.

The only thing holding me back from switching to 18’s is the price difference. NT01’s alone, $190 compared to $330.
Jeff94TA
I suspect our cars are running the same kind of power level. I have Stainless Works long tubes, no cats, Magnaflow cat back, Moroso CAI and a tune. With that said too much tire is a bad thing for my car. I dropped at least 2-3 seconds per lap at Sebring when I stepped back from 315's to 275's and do not miss any grip, the car is very manageable. It just couldn't overcome the mass and rolling resistance of those big ass steam rollers. My best lap at Sebring is a 2:33.499 running in TTC trim on 275's and the track record held by a S2000 is 2.26.499 so I'm exactly seven seconds off the record. Not bad for a lightly modified 23 year old F-body and I'm sure I could get closer to that if I modified it to the limit of the TTC rules and strapped on a bigger set of balls but I'm never going to personally match or beat that track record.

Here are the track records for the Florida Region so you can see what the really fast guys are running at Sebring. Track Records Here

Here is the video of my personal best at Sebring and you can see the car isn't really missing any grip. You can also watch the Corvette in front of me at the start of the video just walk away from me. Video Here

My buddy Ian that holds the TTD & TTE records has tried to convince me to build the car to the limit of the rules using a 245 tire but he's a very talented maniac and has earned his "Mr. Sideways" nickname. I would personally never be able to drive the car that way but I've always wanted to try that set up and let him drive it to see what it could do with him at the wheel. Here is video of him driving a Civic Si race car to a 2:28.914 TTD track record. Video Here
Steve91T
QUOTE (Jeff94TA @ Nov 16 2017, 09:50 AM) *
I suspect our cars are running the same kind of power level. I have Stainless Works long tubes, no cats, Magnaflow cat back, Moroso CAI and a tune. With that said too much tire is a bad thing for my car. I dropped at least 2-3 seconds per lap at Sebring when I stepped back from 315's to 275's and do not miss any grip, the car is very manageable. It just couldn't overcome the mass and rolling resistance of those big ass steam rollers. My best lap at Sebring is a 2:33.499 running in TTC trim on 275's and the track record held by a S2000 is 2.26.499 so I'm exactly seven seconds off the record. Not bad for a lightly modified 23 year old F-body and I'm sure I could get closer to that if I modified it to the limit of the TTC rules and strapped on a bigger set of balls but I'm never going to personally match or beat that track record.

Here are the track records for the Florida Region so you can see what the really fast guys are running at Sebring. Track Records Here

Here is the video of my personal best at Sebring and you can see the car isn't really missing any grip. You can also watch the Corvette in front of me at the start of the video just walk away from me. Video Here

My buddy Ian that holds the TTD & TTE records has tried to convince me to build the car to the limit of the rules using a 245 tire but he's a very talented maniac and has earned his "Mr. Sideways" nickname. I would personally never be able to drive the car that way but I've always wanted to try that set up and let him drive it to see what it could do with him at the wheel. Here is video of him driving a Civic Si race car to a 2:28.914 TTD track record. Video Here



No kidding, so you just didn’t have enough power to overcome the weight and drag of the tires? I would imagine that at the track that I was at, the extra trip would be worth it, but at a place like seabring or VIR, it would have a negative effect because of the long straights. I’ll stick with the 275’s until I get more power. How’s your LSD working? Do you still get right wheel tire spin out of right handers? That’s what’s killing me the most right now.

Your power is probably 290 ish? Do you know what your comp weight is?
nape
I'm not saying that it can't be done, but the AI record there is a 1:43.288 set by Terry Mathis the year he won the National Championship, so probably a pretty good example of a fast AI car. That's on a decent R-compound, the Toyo RR. It's not a Hoosier, but better than a street tire.

It's not impossible to beat a 'vette in an F-body, but it's usually the case of underprepped 'vette vs. all-out F-body, or inexperienced driver vs veteran driver.

Diff and prop valve are a good idea. I'd also recommend the PHB relocation brackets that Unbalanced Engineering makes if you don't already have them.

As far as the weight loss, be diligent about weighing things and prepare to be disappointed. Most people think they're going to lose a bunch of weight doing an LS swap and it usually ends up being less than they figured.
Jeff94TA
QUOTE (Steve91T @ Nov 16 2017, 10:37 AM) *
No kidding, so you just didn’t have enough power to overcome the weight and drag of the tires? I would imagine that at the track that I was at, the extra trip would be worth it, but at a place like seabring or VIR, it would have a negative effect because of the long straights. I’ll stick with the 275’s until I get more power. How’s your LSD working? Do you still get right wheel tire spin out of right handers? That’s what’s killing me the most right now.

Your power is probably 290 ish? Do you know what your comp weight is?


When I was running the 315's it was Hoosiers or Kumho V710's and the mechanical grip was fantastic especially in the slow turns but it wasn't enough to make up for the higher speed sections. I did a lot of autocross back then and they were the ticket. My LSD is a Torsen T2R, one of the early ones, and it has been rock solid. I never spin the inside wheel.

I haven't had my car on a dyno in years but I believe before the 6 speed swap and long tubes it was in the 260's so 290's sound about right. Its run a best of 13.31 in the 1/4 at 105 mph with the current setup. The car weighs just under 3,300 lbs without me in it but I don't remember how much fuel was in it. The only thing I've removed is carpet, headliner and rear panels. It has fiberglass race seats but I've added an Autopower roll bar & harnesses. Car still has working A/C, heat and a full size battery relocated to the hatch area.
SuperMacGuy
I hate to be a party pooper but, man, 11 seconds is a lot. I'd say it might be possible if the LS1 you plan to insert has more than stock HP. Let's say at least a cam, obviously long tubes, LS6 intake, or if you go with heads too then a FAST intake and throttle body combo matching you expected HP levels. Saving weight is always great, but if you are going to build an engine, build it with power so then you don't have to scrape every last ounce out. HP is easier to build more of, than saving weight from parts you want or need to stay street legal and comfortable.
CrashTestDummy
Pressurize the roll bar with nitrous, and plumb it to the intake. 2thumbs.gif

We have a bolt-in in our 95 vert. They laid the back seat down when installing it, so it no longer comes back up. That's okay, because the 'kids' enjoy the better visibility sitting in the back.
Honda93
This will make up the gap, and then some... The right Camaro for the job at hand.

GCrites80s
QUOTE (nape @ Nov 16 2017, 10:46 AM) *
I'm not saying that it can't be done, but the AI record there is a 1:43.288 set by Terry Mathis the year he won the National Championship, so probably a pretty good example of a fast AI car. That's on a decent R-compound, the Toyo RR. It's not a Hoosier, but better than a street tire.

It's not impossible to beat a 'vette in an F-body, but it's usually the case of underprepped 'vette vs. all-out F-body, or inexperienced driver vs veteran driver.

Diff and prop valve are a good idea. I'd also recommend the PHB relocation brackets that Unbalanced Engineering makes if you don't already have them.

As far as the weight loss, be diligent about weighing things and prepare to be disappointed. Most people think they're going to lose a bunch of weight doing an LS swap and it usually ends up being less than they figured.



There's really a lot of metal in LS heads and then you add 7 coils.
dojob
Need to make the decision on how to best go about how you're going to spend your money to buy those 11 secs... new car from the ls1tech classifieds with drivetrain already built, then swap those items onto your car or use that new car and use your existing suspension items on it? Buy items for existing car? Which way makes best use of funds? Lots of good cars for sale that you could use or the items from it, then resale 1 of the cars.
Smitty2919
Can you run Hoosiers? If you can then why aren't you? You mentioned the cost of 18's over 17's is "too much" but also think there are a lot more used 18's out there to be had cheap. Or stick with 17's and buy new.

IMO if you are looking for 11 seconds, fix the brake hop, add a HCI LS1, swap K members, get on a stickier tire than a NT01 and give her hell.

As far as shocks, call UMI and speak to Ramey and get their take on maybe switching to their AFCO C/O setup and or about shocks in general for your goals.

But doing the k member, new eaton TruTrac diff and built (but reliable) LS1 you will have a little coin in that so take advantage and run a stickier tire. Have you corner balanced that car to get the most out of it? Maybe move the battery to the rear passenger fender to load that side and minimize the wheelspin?
79T/A
I agree with smitty, you’ll never get there without Hoosier A7’s.

I would disagree with the battery placement, though. Since it’s a track only car, put it in the back seat wells. Keep the weight in the center of the car in between the wheels. Putting it out beyond the rear wheels just gives it pendulum weight, which is not desirable. If you don’t want to move it, just put one of those tiny 3lb batteries up front.

With an LS1 at a bolt-on power level, 315 Hoosiers, an upgraded shock and spring pacakae, sprinkled with some weight loss, i think you’ll be in the neighborhood. Will you beat corvettes? Probably not, but you will be competitive.
landstuhltaylor
Moving the battery is a waste. Keep it under 2lbs and call it a day
Steve91T
I’m not moving the battery, I’m going to get a lightweight battery in the stock location when my full size one does, which will be soon because mine is old.

About the tires....I think the 315’s on 18’s are going to have to be the last thing I do. I’m going to max out what I can do on 275’s and see how far I get. I keep hearing how Hoosiers are really fast, but only for 1 weekend or even less! 315’s are $400 per tire! That’s a crazy amount of money. Now if I can start winning in my class, I can end up taking home a couple of Hoosiers, but that means I’d have to beat the Vettes. My NT01’s are so consinstant that it’s crazy. Old, new, it doesn’t matter. That means I can run all season on one set, which means I can race more often.

Brakes are the same. My C5’s with Carbotech XP-20’s last forever. Awesome pad. I’m going to switch to the G-loc pad when the time comes (same pad).

I’m really curious to see what kind of a difference the brake bias and lsd make. I felt like I was only able to apply about 2/3’s brake before the rears would start to lock. And I was definitely waiting what felt like forever to be able to put the power down coming out of the turns. Those two things will be a good indication of where I stand right now.

As far as the power...I think TT3 is where I want to stay. It’ll allow me about 350 ish rwhp which is a good number. Enough power to be fun but not so much that I start breaking stuff. A stock LS1 with a very small cam will get there. My dad’s 1SC with a mild cam and stock exhaust manifolds makes 360.

If I can start doing well in my class and come home with a couple of Hoosiers, that would make a big difference, otherwise I don’t think there’s any way I can justify nearly $2k in tires a weekend...I know I can’t.
Mojave
QUOTE (Steve91T @ Nov 22 2017, 10:30 AM) *
I’m not moving the battery, I’m going to get a lightweight battery in the stock location when my full size one does, which will be soon because mine is old.

About the tires....I think the 315’s on 18’s are going to have to be the last thing I do. I’m going to max out what I can do on 275’s and see how far I get. I keep hearing how Hoosiers are really fast, but only for 1 weekend or even less! 315’s are $400 per tire! That’s a crazy amount of money. Now if I can start winning in my class, I can end up taking home a couple of Hoosiers, but that means I’d have to beat the Vettes. My NT01’s are so consinstant that it’s crazy. Old, new, it doesn’t matter. That means I can run all season on one set, which means I can race more often.

Brakes are the same. My C5’s with Carbotech XP-20’s last forever. Awesome pad. I’m going to switch to the G-loc pad when the time comes (same pad).

I’m really curious to see what kind of a difference the brake bias and lsd make. I felt like I was only able to apply about 2/3’s brake before the rears would start to lock. And I was definitely waiting what felt like forever to be able to put the power down coming out of the turns. Those two things will be a good indication of where I stand right now.

As far as the power...I think TT3 is where I want to stay. It’ll allow me about 350 ish rwhp which is a good number. Enough power to be fun but not so much that I start breaking stuff. A stock LS1 with a very small cam will get there. My dad’s 1SC with a mild cam and stock exhaust manifolds makes 360.

If I can start doing well in my class and come home with a couple of Hoosiers, that would make a big difference, otherwise I don’t think there’s any way I can justify nearly $2k in tires a weekend...I know I can’t.


Going faster costs more money. Going 11 seconds faster costs a lot more money. Tires and driver are the two most important things for speed. If your tires last all season, they are not the fastest tires. I'm sure you can find gains from tweaking things, but you're going to have to re-tweak everything when you step up to real tires in a real size. The suspension's job is to keep the tires happy, and changing them will affect the entire setup.
trackbird
QUOTE (Steve91T @ Nov 22 2017, 11:30 AM) *
I’m not moving the battery, I’m going to get a lightweight battery in the stock location when my full size one does, which will be soon because mine is old.


You're never going to win with that attitude. You need to talk to TJ some more. wink.gif

QUOTE (Mojave @ Nov 22 2017, 12:10 PM) *
QUOTE (Steve91T @ Nov 22 2017, 10:30 AM) *
About the tires....I think the 315’s on 18’s are going to have to be the last thing I do. I’m going to max out what I can do on 275’s and see how far I get. I keep hearing how Hoosiers are really fast, but only for 1 weekend or even less! 315’s are $400 per tire! That’s a crazy amount of money. Now if I can start winning in my class, I can end up taking home a couple of Hoosiers, but that means I’d have to beat the Vettes. My NT01’s are so consinstant that it’s crazy. Old, new, it doesn’t matter. That means I can run all season on one set, which means I can race more often.

Brakes are the same. My C5’s with Carbotech XP-20’s last forever. Awesome pad. I’m going to switch to the G-loc pad when the time comes (same pad).

I’m really curious to see what kind of a difference the brake bias and lsd make. I felt like I was only able to apply about 2/3’s brake before the rears would start to lock. And I was definitely waiting what felt like forever to be able to put the power down coming out of the turns. Those two things will be a good indication of where I stand right now.

As far as the power...I think TT3 is where I want to stay. It’ll allow me about 350 ish rwhp which is a good number. Enough power to be fun but not so much that I start breaking stuff. A stock LS1 with a very small cam will get there. My dad’s 1SC with a mild cam and stock exhaust manifolds makes 360.

If I can start doing well in my class and come home with a couple of Hoosiers, that would make a big difference, otherwise I don’t think there’s any way I can justify nearly $2k in tires a weekend...I know I can’t.


Going faster costs more money. Going 11 seconds faster costs a lot more money. Tires and driver are the two most important things for speed. If your tires last all season, they are not the fastest tires. I'm sure you can find gains from tweaking things, but you're going to have to re-tweak everything when you step up to real tires in a real size. The suspension's job is to keep the tires happy, and changing them will affect the entire setup.


He's right. If you're going to beat Corvettes in a Camaro, you're going to have to be spending a fortune on tires and other things. Otherwise, the best advice I can give you is to buy a Corvette. If you're ok with having fun and running mid pack, then you're all ready to go. If you want to win in a class full of Corvettes and you can't out HP them...you're going to have to out tire them. By a LOT. You'll need the fastest tires you can find for a handful of laps at a time.

I bought a C4 a few years ago. The shocks had no oil in them. It was like driving without shocks. I'm almost embarrassed to tell you how well the car changed directions "anyway". Even with virtually no damping. I put a set of cheap Monroe Sensatrac shocks on it so I could drive it for tuning purposes and the car was remarkable (considering it was on junk shocks and the softest factory suspension package). The low center of gravity and IRS, and the ability to brake as hard as I wanted without wheel hop was eye opening. And this was basically the Corvette equivalent of driving a stock Z28 on OEM springs and shocks and swaybars. The deficit is huge between a Camaro and a Corvette. If you can't beat 'em, JOIN 'EM. And that's my best advice.
landstuhltaylor
I've spent a grand total of $250 on tires this year. 5 brand new 335s, 4 used ones. Have a few events on them this year and will likely last me all of 2018.
Steve91T
QUOTE (landstuhltaylor @ Nov 22 2017, 04:01 PM) *
I've spent a grand total of $250 on tires this year. 5 brand new 335s, 4 used ones. Have a few events on them this year and will likely last me all of 2018.



Hoosiers? How is that possible? How long do they last?
Smitty2919
QUOTE (landstuhltaylor @ Nov 22 2017, 03:01 PM) *
I've spent a grand total of $250 on tires this year. 5 brand new 335s, 4 used ones. Have a few events on them this year and will likely last me all of 2018.


This seems misleading for obvious reasons. What parts did you sell to fund the tires, what events did you win to get free tires, who did you know that was unloading said tires for dirt cheap? lol

Like others have said, you won't be winning unless you are on tires that WON'T last a season. Pay to play...orrr win lol. MANY have tried to do what you are doing...building a Camaro to compete against a Corvette, in the end they buy a Corvette.

Spend a lot up front for a Corvette, put a little money into it (tires/shocks/springs) or spend less up front on a Camaro but dump a lot of money into it (shocks/springs/bars/diff/weight loss/315 HOOSIERS/watts link or lowered PHB and more HP) and you MIGHT get close to a Corvette assuming similar drivers.

IMO focus on self improvement/making it reliable and having fun, not winning your class which has Corvette's in it. I'm all for being the "under dog" and beating Corvett's in a Fbody...but you are fighting a losing battle against a decent driver in a Corvette with an OK set of tires on it and an alignment lol.
landstuhltaylor
QUOTE (Smitty2919 @ Nov 22 2017, 04:22 PM) *
QUOTE (landstuhltaylor @ Nov 22 2017, 03:01 PM) *
I've spent a grand total of $250 on tires this year. 5 brand new 335s, 4 used ones. Have a few events on them this year and will likely last me all of 2018.


This seems misleading for obvious reasons. What parts did you sell to fund the tires, what events did you win to get free tires, who did you know that was unloading said tires for dirt cheap? lol


That statement is not misleading in any way whatsoever. Run on good tires and all of the above happens assuming you have the ability to match them. $250 all-in for every single tire that was on my car this season and most of next, before even accounting for what I sold (which brings my costs into negative numbers). Anything that goes on the car next year will also be under $30/tire. I have friends who brought home over 3 sets of Hoosiers for free because they took what was being thrown out behind the Hoosier truck at Nats. Some of those had plenty of speed left.

QUOTE (Steve91T @ Nov 22 2017, 03:59 PM) *
Hoosiers? How is that possible? How long do they last?


Depends on how many runs in each heat cycle. For the single driver stuff I've been doing I get 80-100 fast runs out of them on mostly concrete. The material will last 150 runs or so if you take care of them but they won't be easy to win with.
CrashTestDummy
Wow! We usually get about 60 laps out of our A6’s, but we’re pushing it on really aggressive concrete. IFF we get more than a year before they’re Levi’s, they get replaced because the VOCs are boiled out and you can’t rely on them run-to-run.

But tires are everything. Spend your budget there, upgrade elsewhere as budget allows.
landstuhltaylor
QUOTE (CrashTestDummy @ Nov 22 2017, 10:06 PM) *
Wow! We usually get about 60 laps out of our A6’s, but we’re pushing it on really aggressive concrete. IFF we get more than a year before they’re Levi’s, they get replaced because the VOCs are boiled out and you can’t rely on them run-to-run.

But tires are everything. Spend your budget there, upgrade elsewhere as budget allows.


You are still using A6s or is that a typo? The A7 stays fast much, much longer than the A6 does. They both have the same compound but the construction changed significantly.
CrashTestDummy
Oops! Too many ‘Rita’s and not enough sleep. We’re on Hoosier slicks.
landstuhltaylor
QUOTE (CrashTestDummy @ Nov 23 2017, 09:50 AM) *
Oops! Too many ‘Rita’s and not enough sleep. We’re on Hoosier slicks.


Yeah I've heard that's normal, and there is at least some evidence that they may not be any faster. More ultimate grip but they don't transition as well.
nape
QUOTE (Steve91T @ Nov 22 2017, 10:30 AM) *
It’ll allow me about 350 ish rwhp which is a good number. Enough power to be fun but not so much that I start breaking stuff.


Heh, breaking stuff just comes with hitting the track. The number of transmissions and diffs that I've gone through in the last 10 years would make a sane person cry.

"Hey Dad, what're all those parts on the shelf?"

Those? That's probably a year or two of college at a good state school. rotf.gif
CrashTestDummy
QUOTE (landstuhltaylor @ Nov 23 2017, 05:22 PM) *
QUOTE (CrashTestDummy @ Nov 23 2017, 09:50 AM) *
Oops! Too many ‘Rita’s and not enough sleep. We’re on Hoosier slicks.


Yeah I've heard that's normal, and there is at least some evidence that they may not be any faster. More ultimate grip but they don't transition as well.


The radial slicks seem to transition better than the old bias plies. They do take a little more air, though.
Steve91T
About relocating the battery....it’s not that I’m not willing to do the work, I just don’t want the weight of the added cables. I’m going to just get a tiny battery in the stock location.


Another thing that I need to consider is since the time trial class that I’m in (TT3), it is based solely on power to weight. Running wider than a 275 and also a non DOT tire come with penalties. I’m not sure exactly how much, might be as much as 20-30 hp. So I don’t know if I’d have the power to overcome a 315. But maybe Hoosiers in 275’s might be an option? I definitely want to try them now that I know they last longer than just one weekend.
SuperMacGuy
Oh I did not know you were running in a such a restricted class, I thought it was just kind of open lapping or unlimited etc. Now I'm going to say, stop the insanity. If you want to run with or catch Corvettes, buy one. You will likely never be able to stay within the class rules AND beat other cars already better engineered to start with. I don't want to be a downer, but the quest seems unreasonable. If you love your F-body and want to do the best, great. I'm not saying don't have fun. But "winning" might require a different car.
nape
QUOTE (Steve91T @ Nov 27 2017, 08:47 PM) *
But maybe Hoosiers in 275’s might be an option? I definitely want to try them now that I know they last longer than just one weekend.


Hoosier last more than a weekend, but they start to slow down after 3-5 heat cycles (my experience with R6s). By all means, try them. Purple crack is great if you can keep winning them.
landstuhltaylor
I've never driven the R tires so I can't comment on those. I do know that A7s stay fast well past 3-5 cycles, but the envelop does get smaller very slowly. Eventually though you will take them out and they will be garbage all day long.

I would never use the A7 on a racetrack unless it was one and done fliers. After 3 runs on a 60 second course they will need to be sprayed even with 1 driver in the car and 75F temps.
Steve91T
My next race will be at the same track in February, so should be similar conditions.

It’ll be really interesting to see what kind of a difference just fixing the brake bias and LSD make.
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