SCCA Solo D Street discussion

[Jack Black]

Originally Posted by Mball19

I autocrossed my 86 in DS for the first time Sunday. It was a lot more fun than my WRX. Two things it definitely needs right away.
1. Front Sway bar. I was looking at the 22mm Perrin front bar. Are there better options in the $200 range? Is the Hotchkis bar to much with the stock rear bar?

I got my front bar from Strano Parts. It's the one he specifically designed for the twins when he was running one. I don't see one on the website right now, but you could try calling and asking about it.

[Mball19]

I have autocrossed my 86 twice with mixed results. The first event was with camber bolts and everything else stock. The car was very drifty on throttle. The second event I added a Perrin 22mm front bar (full soft) and RE71rs. The car became very pushy and wouldn’t rotate under throttle at all. I am thinking about going back to the stock front bar to get more rotation. What do you think?

[TMF]

Originally Posted by Mball19

I have autocrossed my 86 twice with mixed results. The first event was with camber bolts and everything else stock. The car was very drifty on throttle. The second event I added a Perrin 22mm front bar (full soft) and RE71rs. The car became very pushy and wouldn’t rotate under throttle at all. I am thinking about going back to the stock front bar to get more rotation. What do you think?

One easy thing that you can do to help with the corner exit oversteer is toe-in the rear. That will help to get the power down easier and less "drifty".

Sway bar options, as I recall, I think the need for a bigger front bar is course dependent....lots of transitions/slaloms=bigger front bar. More long sweepers= stock front bar.

Expensive, but very adjustable:
http://www.karcepts.com/shop/product.php?id_product=136

[strat61caster]

Front bar is pretty common, most go milder than you did with a 19/20mm bar, you probably went too far. User preference at this point, going back to stock bar with a bit more toe in seems like the funner solution to me.

[nico_rsx]

Originally Posted by TMF

Expensive, but very adjustable:
http://www.karcepts.com/shop/product.php?id_product=136

A lot of adjustement, but even the softer adjustement is 55% harder than stock, which may be too much in some cases

[steverife]

If you thought the Karcepts setup as packaged is too much bar rate, you could replace the center splined bar with one with a thinner wall. I think .12" and .095" walls are also common.... though that probably puts you towards the other end of having a lot of adjustments that you probably don't want.

[Locust]

Originally Posted by Mball19

I have autocrossed my 86 twice with mixed results. The first event was with camber bolts and everything else stock. The car was very drifty on throttle. The second event I added a Perrin 22mm front bar (full soft) and RE71rs. The car became very pushy and wouldn’t rotate under throttle at all. I am thinking about going back to the stock front bar to get more rotation. What do you think?

Camber bolts or the OEM crash bolts? What is your front camber? What are your tire pressure settings?

[TrqlessWonder]

Originally Posted by strat61caster

Front bar is pretty common, most go milder than you did with a 19/20mm bar, you probably went too far. User preference at this point, going back to stock bar with a bit more toe in seems like the funner solution to me.

Alternatively, could just choose to open up the toe at the rear with the big bar.

At 2 events in a new platform, both with very different setups (OE to RE/big bar is a big jump), I'm still closer to making sure the install went correctly/as-intended before I'm wondering if I made the wrong choices.

There's a couple other adjustment knobs available in Street. Did you play with tire pressure?

[Roadphantom]

Originally Posted by Mball19

I have autocrossed my 86 twice with mixed results. The first event was with camber bolts and everything else stock. The car was very drifty on throttle. The second event I added a Perrin 22mm front bar (full soft) and RE71rs. The car became very pushy and wouldn’t rotate under throttle at all. I am thinking about going back to the stock front bar to get more rotation. What do you think?

Are you autocrossing on a tight and slow parking lot? Share some video if you have.

Sent from my Pixel 2 using Tapatalk

[Mball19]

Originally Posted by Locust

Camber bolts or the OEM crash bolts? What is your front camber? What are your tire pressure settings?

OEM crash bolts. I am not sure what the camber is. I was running 35psi square.



The car felt great in slaloms and transitions. It pushed in turn arounds and big sweepers. I am looking at the TRD bars.

[Mball19]

Originally Posted by TrqlessWonder

Alternatively, could just choose to open up the toe at the rear with the big bar.

At 2 events in a new platform, both with very different setups (OE to RE/big bar is a big jump), I'm still closer to making sure the install went correctly/as-intended before I'm wondering if I made the wrong choices.

There's a couple other adjustment knobs available in Street. Did you play with tire pressure?

I haven't played with pressure. It started raining after 3 runs, so I didn't adjust anything. The sway bar install went fine.

[nico_rsx]

Originally Posted by Mball19

OEM crash bolts. I am not sure what the camber is. I was running 35psi square.

35 psi is that with RE71R ?
If yes, that's too much. I run 30 front and 28 rear when hot (adjusted 1-2 minutes after a run).
I have OEM crash bolts (around -1deg) and OEM sway bars.

[TrqlessWonder]

Originally Posted by Mball19

I haven't played with pressure. It started raining after 3 runs, so I didn't adjust anything. The sway bar install went fine.

When you change a part, you're changing the setup. Which means you'll need to figure out how to make that setup work well. Not much you can change that acts in complete isolation.

Keeping the back end behind me with a stock front bar would probably make me want to run a fair amount of toe-in at the rear. Going to a big bar and nothing else means that I now have too much toe-in at the rear, because the toe was to tame the rear end, but the new bigger bar does that too, so you have to re-balance the car. Which means finding a balance.

Which means trying things to make something work. Including the driver making accommodations. "Feels like a dump truck/It's trying to kill me, but I'm faster."

Not many folks can nail the settings on a new setup in 3 runs. So, yeah. Maybe go through the time/effort to gather some more data before making the next change.

[Locust]

35 PSI is way too high. That's what I run my cars at for daily driving...

If you're on the crash bolts you should be in the realm of -1.0 to -1.8 camber in the front and your rears are probably stuck right around -0.8 and won't ever move. You can use toe to play with the turn-in a little but you're pretty far off on all the rest so I would go with 0 toe all around for now and focus on getting the right parts on the right ends of the car.

Since this is D-Street you're limited to OEM rear bar so your 22mm is too much for the front. Most people go 20mm and a tiny bit of rear toe in. A 22mm worked when the TRD rear bar was allowed.

My pressures that I ran on RE71R were 28 front / 26 rear. BFG was 29 front / 26 rear. That was with a 20mm whiteline FSB and off the shelf Koni yellows (with the mandatory centering washer). You can adjust a little up or down for your setup and driving preferences but if you're running a square pressure setup then something is off. I can't recall a highly competitive car that wasn't running staggered pressures.