After over a year of driving on the stock suspension, with the only change to it being the use of Koni Sport shocks and camber plates, I finally decided to make some changes to it. I had already planned to do this, but the recent experience with noticing the delay in taking a set merely added to the incentive.
These changes are not a whole lot in terms of rates or anything. Essentially, I've stiffened the springs by about 13%, and stiffened the rear sway bar by 42%. I've done this while dropping the front by about 0.4", and the rear by essentially nothing. While I was at it, because it was so cheap as to almost be free, I also replaced the rear panhard bar.
Replacement springs from Ford are dirt cheap: about $25 each. This makes experimentation with them almost painless in terms of money spent.
I realize the Boss 302 in stock form is laughed at around here, but that doesn't matter to me. I was curious how the thing handles, and why it has the sort of reputation it does (this forum excluded). Because I don't have one, but the springs are so inexpensive as to be almost free, and I wanted to make a change to the car that would liven it up a bit while maintaining its streetability, I went with the Boss 302 springs and rear sway bar.
What I was after were cornering characteristics essentially matching those of the Laguna Seca package. One would think that doing that would mean slapping on its springs and rear sway bar and that would be that. But in this case, I'm running a square setup. When I computed the percentage difference in grip between my front tires (285mm width) and the Boss 302 front tires (255mm width), I get about 12% difference. The percentage difference between the Laguna Seca front springs and the standard Boss 302 front springs is about 9%.
I opted to use the Laguna Seca springs in the rear, and the standard Boss 302 springs in the front. That gets me 148 lb/in up front (Laguna Seca springs up front are 136 lb/in), and 191 lb/in in the rear. The 26mm sway bar in the rear is worth 275 lb/in, up from 193 lb/in with the stock 24mm bar. And because the Laguna Seca panhard bar is actually different from the stock one (the standard Boss panhard is not), I expected it would have stiffer bushings that would make it easier to feel the rear end. At $50 for it, I couldn't pass it up. Based on the grip difference in the front versus the spring rate difference, I would expect a little more oversteer from my car than from a stock Laguna Seca.
You might think that these changes would result in minimal changes to the handling characteristics of the car. But the end result was surprising to me. Whereas before, the car most definitely took some time to take a set when pitched into a corner, this one seems to take a set quickly enough that I can't detect the delay. It could be that I need more experience in order to start seeing that, but the point here is that the change in responsiveness is much greater than I would have expected.
There is still some neutral-throttle corner entry understeer. It feels like there's less of that than before. It's noticeably easier to get the car to oversteer than before, and indeed it seems to mildly oversteer on its own mid-corner. This combination of greater oversteer and faster turn-in makes the car a delight to me, an improvement much greater than I expected. After all, I was expecting that the Boss 302 was nothing more than a glorified GT in terms of its suspension, that would understeer like a pig and move all over the place in the corners, since that seems to be the consensus around here as regards stock suspensions. I suppose it's all relative. The thing feels lively and responsive, very easy to control, but reasonably well buttoned down at the same time (roll is somewhat reduced, but it feels quite a bit more solid in roll). It'll oversteer at will, whether life-throttle or on-throttle, but does so in such a way that it's easy to control.
Strangely, the dampers feel happier with these springs than with the stock ones. I don't know how exactly to describe it.
The only problem, which is fortunately not a problem for me yet, is that the most camber I can get is about -2.1 degrees. The reason it's not a problem is that the RE-11s on the car seem to wearing the same front versus rear now, even after 5 track days (2 on the stock springs/sways, 3 on the new ones, but with basically the same camber up front). As long as that remains the case, then the camber is sufficient. I can't get any more because more would result in the spring contacting the inside of the strut tower. Which clearly means that if/when I end up needing more camber, it'll be time to go to coilovers.
With the new setup, I took the car to Sonoma Raceway. The first time was for the purpose of refreshing my knowledge of the track. I signed up for a "stage 2" round of Simraceway's driving school. This gets you 4 track sessions of 25 minutes each, plus a number of laps around an autocross-format course that they set up (which is really more like a mini-track than a real autocross course, as it doesn't have the usual autocross features like slaloms, chicago boxes, etc.). The latter was one of the major reasons I signed up for this -- it would allow me to feel out the car's limits without putting the car in danger of hitting anything.
There were some very fast cars there. A couple McLaren 650S, a Ferrari 430, an Aston Martin Vanquish, a BMW M5, a Corvette C7 Z06, and a few others I can't remember. In this company, you'd think I'd be among the slowest of the lot. Apparently not, though one of the McLarens was very fast indeed. The instructor noted that I was keeping up with that particular driver and car in the corners but couldn't keep up in the straight sections. I guess this means the driver mod is working.
The real fun was during the next event at Sonoma. This was a NASA 2-day event, and the first event in which I drove in HPDE group 3. Strangely, I felt right at home. I started near the back of the group during the first couple of sessions because I wanted to ensure that I wouldn't really get in anyone's way if I was too slow. That turned out not to be a problem. Indeed, the opposite turned out to be the case more than once, where I got caught up behind a stream of traffic. Starting near the middle tended to work better in the end.
We started the first day with group 2 passing rules, expanded that some in the second session, and was doing open passing by the 4th session. Aside from the first session (in which we're combined with group 2), the second day was entirely open passing. It was really nice to have the freedom to pass anywhere on the track. It'll take some experience to build the judgment as to when a pass will work well and when it won't, but that won't be a problem. The main problem is passing groups of cars. Injecting yourself into a stream of cars requires that you have a lot of trust in the ability of the other drivers to see you and act accordingly, and I'm not exactly comfortable with that. That may change with time.
So with the car set up as it is now, I'm rather happy with it, and will concentrate on the driver mod for a while, at least until I start to notice something about its handling that I want to see improved. There's no telling how long that'll take, but the fun is in the journey, not the end!
These changes are not a whole lot in terms of rates or anything. Essentially, I've stiffened the springs by about 13%, and stiffened the rear sway bar by 42%. I've done this while dropping the front by about 0.4", and the rear by essentially nothing. While I was at it, because it was so cheap as to almost be free, I also replaced the rear panhard bar.
Replacement springs from Ford are dirt cheap: about $25 each. This makes experimentation with them almost painless in terms of money spent.
I realize the Boss 302 in stock form is laughed at around here, but that doesn't matter to me. I was curious how the thing handles, and why it has the sort of reputation it does (this forum excluded). Because I don't have one, but the springs are so inexpensive as to be almost free, and I wanted to make a change to the car that would liven it up a bit while maintaining its streetability, I went with the Boss 302 springs and rear sway bar.
What I was after were cornering characteristics essentially matching those of the Laguna Seca package. One would think that doing that would mean slapping on its springs and rear sway bar and that would be that. But in this case, I'm running a square setup. When I computed the percentage difference in grip between my front tires (285mm width) and the Boss 302 front tires (255mm width), I get about 12% difference. The percentage difference between the Laguna Seca front springs and the standard Boss 302 front springs is about 9%.
I opted to use the Laguna Seca springs in the rear, and the standard Boss 302 springs in the front. That gets me 148 lb/in up front (Laguna Seca springs up front are 136 lb/in), and 191 lb/in in the rear. The 26mm sway bar in the rear is worth 275 lb/in, up from 193 lb/in with the stock 24mm bar. And because the Laguna Seca panhard bar is actually different from the stock one (the standard Boss panhard is not), I expected it would have stiffer bushings that would make it easier to feel the rear end. At $50 for it, I couldn't pass it up. Based on the grip difference in the front versus the spring rate difference, I would expect a little more oversteer from my car than from a stock Laguna Seca.
You might think that these changes would result in minimal changes to the handling characteristics of the car. But the end result was surprising to me. Whereas before, the car most definitely took some time to take a set when pitched into a corner, this one seems to take a set quickly enough that I can't detect the delay. It could be that I need more experience in order to start seeing that, but the point here is that the change in responsiveness is much greater than I would have expected.
There is still some neutral-throttle corner entry understeer. It feels like there's less of that than before. It's noticeably easier to get the car to oversteer than before, and indeed it seems to mildly oversteer on its own mid-corner. This combination of greater oversteer and faster turn-in makes the car a delight to me, an improvement much greater than I expected. After all, I was expecting that the Boss 302 was nothing more than a glorified GT in terms of its suspension, that would understeer like a pig and move all over the place in the corners, since that seems to be the consensus around here as regards stock suspensions. I suppose it's all relative. The thing feels lively and responsive, very easy to control, but reasonably well buttoned down at the same time (roll is somewhat reduced, but it feels quite a bit more solid in roll). It'll oversteer at will, whether life-throttle or on-throttle, but does so in such a way that it's easy to control.
Strangely, the dampers feel happier with these springs than with the stock ones. I don't know how exactly to describe it.
The only problem, which is fortunately not a problem for me yet, is that the most camber I can get is about -2.1 degrees. The reason it's not a problem is that the RE-11s on the car seem to wearing the same front versus rear now, even after 5 track days (2 on the stock springs/sways, 3 on the new ones, but with basically the same camber up front). As long as that remains the case, then the camber is sufficient. I can't get any more because more would result in the spring contacting the inside of the strut tower. Which clearly means that if/when I end up needing more camber, it'll be time to go to coilovers.
With the new setup, I took the car to Sonoma Raceway. The first time was for the purpose of refreshing my knowledge of the track. I signed up for a "stage 2" round of Simraceway's driving school. This gets you 4 track sessions of 25 minutes each, plus a number of laps around an autocross-format course that they set up (which is really more like a mini-track than a real autocross course, as it doesn't have the usual autocross features like slaloms, chicago boxes, etc.). The latter was one of the major reasons I signed up for this -- it would allow me to feel out the car's limits without putting the car in danger of hitting anything.
There were some very fast cars there. A couple McLaren 650S, a Ferrari 430, an Aston Martin Vanquish, a BMW M5, a Corvette C7 Z06, and a few others I can't remember. In this company, you'd think I'd be among the slowest of the lot. Apparently not, though one of the McLarens was very fast indeed. The instructor noted that I was keeping up with that particular driver and car in the corners but couldn't keep up in the straight sections. I guess this means the driver mod is working.
The real fun was during the next event at Sonoma. This was a NASA 2-day event, and the first event in which I drove in HPDE group 3. Strangely, I felt right at home. I started near the back of the group during the first couple of sessions because I wanted to ensure that I wouldn't really get in anyone's way if I was too slow. That turned out not to be a problem. Indeed, the opposite turned out to be the case more than once, where I got caught up behind a stream of traffic. Starting near the middle tended to work better in the end.
We started the first day with group 2 passing rules, expanded that some in the second session, and was doing open passing by the 4th session. Aside from the first session (in which we're combined with group 2), the second day was entirely open passing. It was really nice to have the freedom to pass anywhere on the track. It'll take some experience to build the judgment as to when a pass will work well and when it won't, but that won't be a problem. The main problem is passing groups of cars. Injecting yourself into a stream of cars requires that you have a lot of trust in the ability of the other drivers to see you and act accordingly, and I'm not exactly comfortable with that. That may change with time.
So with the car set up as it is now, I'm rather happy with it, and will concentrate on the driver mod for a while, at least until I start to notice something about its handling that I want to see improved. There's no telling how long that'll take, but the fun is in the journey, not the end!
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