Track Handling on an OEM suspension
#1
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Track Handling on an OEM suspension
Looking for some advice or experience on how to make the best handling package within limitations:
In the series we race in ANY non-OEM specification part from the original build of a base car from the factory is subject to a lap penalty. However, modifying the OEM parts is free. OEM specs for a 1994 are as follows:
154/97 lb/in springs
OEM Dampers with bump stops + top hats
19mm Front sway bar
11mm Rear sway bar
Current thought is to first replace the shocks with an "OEM repalcement" like KYB GR2 or more likely the Koni STR.T --- Any other OEM replacement shock we should consider? (Bilsteins are considered an aftermarket upgrade and incur a penalty as they are not on the base Miata unfortunately)
Second, we would be looking to remove a free coil or two on the springs in an effort to increase the spring rate and lower the car. We will also replace the OEM bumpstops with shortened ones.
Lastly, we are looking to drill a new hole up on the OEM front sway bar to shorten the torque arm length and essentially stiffen the system. Possibly removing the rear bar to bias towards slight understeer but preferably nuetral.
If you had to replace one part with aftermarket, what would it be (besides the shocks)? We are thinking the front sway bar
Thoughts or experience is welcomed, thanks in advance
In the series we race in ANY non-OEM specification part from the original build of a base car from the factory is subject to a lap penalty. However, modifying the OEM parts is free. OEM specs for a 1994 are as follows:
154/97 lb/in springs
OEM Dampers with bump stops + top hats
19mm Front sway bar
11mm Rear sway bar
Current thought is to first replace the shocks with an "OEM repalcement" like KYB GR2 or more likely the Koni STR.T --- Any other OEM replacement shock we should consider? (Bilsteins are considered an aftermarket upgrade and incur a penalty as they are not on the base Miata unfortunately)
Second, we would be looking to remove a free coil or two on the springs in an effort to increase the spring rate and lower the car. We will also replace the OEM bumpstops with shortened ones.
Lastly, we are looking to drill a new hole up on the OEM front sway bar to shorten the torque arm length and essentially stiffen the system. Possibly removing the rear bar to bias towards slight understeer but preferably nuetral.
If you had to replace one part with aftermarket, what would it be (besides the shocks)? We are thinking the front sway bar
Thoughts or experience is welcomed, thanks in advance
#4
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I'm not looking forward to it, especially after going through several hours of testing/tuning with open rules to land on the suspension we ran at the end of this year at Road America, handled amazing!
#8
I don't have any good resources on hand unfortunately for the shock revalving, but you basically just take a stock shock, drill it, drain it, fit a valve on it and fill it up with new oil, and then spend the better part of the day acting as a manual shock dyno pumping the shock by hand until it firms up.
I can't remember what the cost is for the sleeves and springs, but you might be able to get away with like $50 over (aka +2 laps) AIV by going with an eBay sleeve and springs and using your hand revalved stock shocks.
edit: Non-OE coil springs (including ‘coil-over’ kit): $20/corner
So technically you can get away having your car still come under $500 with this. You'll need to play with the spring rates to figure out what works with the stock sway bars or try to size up/down the rear to 11/12mm.
I can't remember what the cost is for the sleeves and springs, but you might be able to get away with like $50 over (aka +2 laps) AIV by going with an eBay sleeve and springs and using your hand revalved stock shocks.
edit: Non-OE coil springs (including ‘coil-over’ kit): $20/corner
So technically you can get away having your car still come under $500 with this. You'll need to play with the spring rates to figure out what works with the stock sway bars or try to size up/down the rear to 11/12mm.
#11
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I don't have any good resources on hand unfortunately for the shock revalving, but you basically just take a stock shock, drill it, drain it, fit a valve on it and fill it up with new oil, and then spend the better part of the day acting as a manual shock dyno pumping the shock by hand until it firms up.
I can't remember what the cost is for the sleeves and springs, but you might be able to get away with like $50 over (aka +2 laps) AIV by going with an eBay sleeve and springs and using your hand revalved stock shocks.
I can't remember what the cost is for the sleeves and springs, but you might be able to get away with like $50 over (aka +2 laps) AIV by going with an eBay sleeve and springs and using your hand revalved stock shocks.
We had an eBay sleeve setup with Summit springs, but springs are now $80 and out of the question moving forward 2014-on
Every $10 over the $500 limit is a one lap penalty... rounded up. With the competition being as tight as it is, especially against the e30 and e36 crowd, we can't afford any laps.
#12
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Not allowed in chump car.
Might possibly be allowed, and or really cheap.
I have no clue is Koni STRT's would be legal or not, but I bet if you show up with konis and the techs notice them they will not be happy, even if they are "oem".
Might possibly be allowed, and or really cheap.
I have no clue is Koni STRT's would be legal or not, but I bet if you show up with konis and the techs notice them they will not be happy, even if they are "oem".
#13
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shuiend speaks the truth
An R-Package is "allowed" but will be assigned a starting value of "north of $600" for some un-holy reason. Conversions are not allowed however
Tirerack lists the STR.T Koni as an OEM replacement so I would assume they are allowed. Even so, are they the best option over the KYB GR2? Shaikh has posted in several threads that he prefers the performance of the GR2 over that of the Koni due to the Koni's weak damping curves and tendency to lose consistent performance via heat generation from their internal design. Anyone else have input?
An R-Package is "allowed" but will be assigned a starting value of "north of $600" for some un-holy reason. Conversions are not allowed however
Tirerack lists the STR.T Koni as an OEM replacement so I would assume they are allowed. Even so, are they the best option over the KYB GR2? Shaikh has posted in several threads that he prefers the performance of the GR2 over that of the Koni due to the Koni's weak damping curves and tendency to lose consistent performance via heat generation from their internal design. Anyone else have input?
#17
Not on any team (haven't driven since 2012) and Southeast. :v
I think it'd be worth the $20 hit to run the coilover setup because you will be able to change your spring rates to make your sway bars work. It's somewhat unfortunate that the Miata isn't competitive because it's so low in HP and so high in AIV.
I think it'd be worth the $20 hit to run the coilover setup because you will be able to change your spring rates to make your sway bars work. It's somewhat unfortunate that the Miata isn't competitive because it's so low in HP and so high in AIV.
#18
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Not on any team (haven't driven since 2012) and Southeast. :v
I think it'd be worth the $20 hit to run the coilover setup because you will be able to change your spring rates to make your sway bars work. It's somewhat unfortunate that the Miata isn't competitive because it's so low in HP and so high in AIV.
I think it'd be worth the $20 hit to run the coilover setup because you will be able to change your spring rates to make your sway bars work. It's somewhat unfortunate that the Miata isn't competitive because it's so low in HP and so high in AIV.
The Miata is very competitive in the SouthWest, particularly Texas. I agree though, it's doesn't seem that the new valuation is quite on par. We'll have to see how it pans out this season. We think we still have a very competitive package the way it's put together.
We may be at AMP this year, check out our website and let us know if you'd like to get back in the saddle!
#19
I'm sorry I thought this was another one of those guys in that weird canadian racing leauge, where doring pretty much anything other than running stock was considered stock. I'm sure they got penalized for having less than half a tank of gas and taking a poop before racing if it wasnt in the factory manual.
#20
Possibly, I'd like to explore every free option first. Most of the TCV budget will need to go towards power adders.
The Miata is very competitive in the SouthWest, particularly Texas. I agree though, it's doesn't seem that the new valuation is quite on par. We'll have to see how it pans out this season. We think we still have a very competitive package the way it's put together.
We may be at AMP this year, check out our website and let us know if you'd like to get back in the saddle!
The Miata is very competitive in the SouthWest, particularly Texas. I agree though, it's doesn't seem that the new valuation is quite on par. We'll have to see how it pans out this season. We think we still have a very competitive package the way it's put together.
We may be at AMP this year, check out our website and let us know if you'd like to get back in the saddle!
Thanks for the offer.