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01-11-2024, 01:50 PM | #23475 | |
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Otherwise, yes. If you already have a coilover setup with decent spring rates, adding on the front bar alone will just make the car understeer more. |
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01-11-2024, 09:34 PM | #23476 |
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The problem though, the PO had a RDsport bar on and the bushing are worn out. I am also on B12 pro kit so not exactly full stock. I want to make it a step forward for more track days build. But also open to a better route.
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01-12-2024, 10:49 AM | #23477 |
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The B12 kit is still quite soft spring rates. So I'd say adding the front bar on its own will be fine and be a net positive result.
I think the Hotchkis bar is the best available since it's the most adjustable. |
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01-12-2024, 01:56 PM | #23478 |
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I was looking at this bar as a band-aid solution with my Ohlins R&T but was concerned about just increasing understeer as was mentioned. Any thoughts on where the line is in terms of benefit/hinderance ?
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01-12-2024, 02:09 PM | #23479 | |
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I'd guess it's probably getting to the limit of where it would actually help. Good chance it just adds some understeer unless you add a rear bar upgrade at the same time. |
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01-12-2024, 04:04 PM | #23480 |
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342/685 lbs/in is the off the shelf Ohlins RT setup.
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01-12-2024, 05:59 PM | #23481 |
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Yes, these are the rates I've got
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01-14-2024, 02:45 PM | #23482 |
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This is not true. The front subframe is pinned. I confirmed this and there isn’t enough play to affect camber more than a fraction of a degree. Plus there are 8 bolts holding it up.
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01-14-2024, 05:20 PM | #23483 |
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There's almost zero play in the front subframe. I tried to get rigid collars installed once and it was a bitch cos the tolerances in the bolt holes were super tight.
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01-15-2024, 09:38 AM | #23484 | |
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Last edited by Richbot; 01-15-2024 at 09:44 AM.. |
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01-15-2024, 01:35 PM | #23485 |
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Has anyone experimented with bump springs up front? I need a solution that does not require increasing the front spring rate over 900 lbs since I like the current feel, but my splitter is getting trashed at Buttonwillow.
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01-15-2024, 02:21 PM | #23486 |
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Love this! I assume the splitter thrashing is coming from aeroload near the back end of straights and into initial braking?
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01-15-2024, 03:35 PM | #23487 |
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I think it's happening all over, but in particular on Off Ramp (nasty off camber right hander) and Riverside (high speed sweeper).
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01-15-2024, 05:07 PM | #23488 |
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Hmmm, please let us know where you land between a spring vs rubber. But if you feel under sprung in corners, then you’d want to go up in spring rate (which you said you didn’t want to do) or dial up the sway bar? I’m not a suspension engineer, just trying to visualize. Hopefully someone competent pipes in.
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01-15-2024, 08:19 PM | #23489 | |
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they did touch on how easy it can be to tune spring rates and bump stops using spring rubbers. the key point i remember (its been a while) was using a bumpstop that wasn't too firm because it can cause a sudden loss of traction. if the bump is too firm, it can result in a sudden loss of traciton. the cool part is, these parts aren't expensive and can be easily swapped out for a test 'n tune day. https://www.resuspension.com/bump-stops.html
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01-15-2024, 08:26 PM | #23490 | |
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Bump rubbers are little devices you insert into the spring to in effect reduce the spring by a full coil thereby increasing the spring rate. Those are easy to install. Can also be a solution to getting non permanent ride height for loading on a trailer. There are some excellent HPA materials on bump stop / spring tuning. Their 10 min overview is at a bare minimum helpful to orient to concepts.
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01-15-2024, 08:37 PM | #23491 |
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i sort of remember it being said you could cut/zip tie the bump stops on to experiment and tune, and then do a proper install once you find something you're happy with.
i'm not at this point yet, i'm just relaying what i've learned about. zero personal experience here.
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01-15-2024, 08:46 PM | #23492 | |
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Edit: i see the flat disk style bump stops that you’re likely referring to roastbeef. I take it back!
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01-15-2024, 08:59 PM | #23493 | |
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i did see these bump stop cups. it looks like you install these at the end of the shaft and stuff a bump stop into it. i suppose the walls would prevent it from blowing out. i'm not sure how you'd get it out quickly or without destroying it though... mabe lube it up and install a pull ribbon? https://www.resuspension.com/bump-st...cup-625-1.html
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01-16-2024, 03:43 PM | #23494 | |
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Bump stops are cheap and bump shims can be easily added/removed to change damper travel (could do this with bump springs, too, but it’s likely there’s no no available length to incorporate them). Bump stop are more compact and much easier to integrate (bump springs are quite long compared to a bump stop). Not saying bump springs don’t have advantages because they do, such as a wider range of available stiffness, stiffness not affect by temperature, length and stiffness remains constant/repeatable with abuse, etc. For keeping a splitter from bottoming out, I’d choose a bump stop over a bump spring especially if you’re running with a 5” main spring - bump springs are ~+/-4” long so you’ll start using them more frequently and, therefore, alternating your main spring rate. Bump stops will better protect the splitter in unexpected events, running different lines, etc. Last edited by M3SQRD; 01-17-2024 at 11:53 AM.. |
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01-16-2024, 05:13 PM | #23495 |
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This is a very helpful discussion, but unfortunately way above my tech level. That said, it sounds like it would be better to start with bump stops. I was just concerned about them unsettling the car but, again, that is due to my lack of technical understanding.
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01-16-2024, 06:07 PM | #23496 | |
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https://youtu.be/jXpprCRQzH8?feature=shared
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