Alignment handling changes

[dmann]

In reading my weekly speed secrets article it got me to thinking about my next track day outing.
My first track day in this car was with stock alignment, I noticed some understeer on the exit of some corners.
The next track day will be with the TA alignment.
Given that the numbers look vastly different it seems that i will have more oversteer with this setup.
Should i be concerned about the rear end kicking out(straights and corners) because of this more aggressive setup?

-David

Update: I should make note that this is a Gen V.

[GTSilver]

It all depends on your driving style. I've ran the TA alignment and also had understeer so I think you'll be fine in regards to oversteer.

[dmann]

Did you have the GT/GTS alignment prior? No kickout in the rear afterward?

[Cybermig]

I've run the GTS, TA and ACR alignments and I can say they're progressive improvements over each other in terms of track performance, turn in is quicker with each improvement and also the front end sharpness increases as well as you increase camber. Daily drive-ability suffers a little unless you like the feeling of driving on rails with uber responsive steering. But if you street/track you car, I recommend the ACR alignment over the TA particularly if you have some R-Compound tires to go with it.

[dmann]

Cyber, Interesting take on this.
Thanks

[GTSilver]

Did you have the GT/GTS alignment prior? No kickout in the rear afterward?

No I started with the TA alignment and then after that I went a bit more aggressive than the ACR alignment. I agree with what have written if you are on a R compound tire start with the ACR or a bit more in regards to camber.

[Exhlr8n]

Here is Mark J from Woodhouse's response when I asked for my ACR-E

The standard SRT approved set up is -2.8 front and 6 for castor, we use 0 toe.
Rear -1.7 castor stays stock at .7 and we use .20 degrees total toe in.

Depending on your style the camber can vary of course so there is no one perfect set up I recommend Tom, if it was my own I know that I would lose at least .3 of the camber at both ends.

Been pretty happy with it overall, regadless of setup it always seems to have a little understeer, I did like the crisp response with -2.8 Front Camber, seems a bit less responsive, so I may go back to -2.8.

[dmann]

@exhlr8n- I'm not understanding your comment.
You have an ACR-E but Mark said that a base SRT is to be set at what an ACR is set to?

[IHOP]

I've run the GTS, TA and ACR alignments and I can say they're progressive improvements over each other in terms of track performance, turn in is quicker with each improvement and also the front end sharpness increases as well as you increase camber. Daily drive-ability suffers a little unless you like the feeling of driving on rails with uber responsive steering. But if you street/track you car, I recommend the ACR alignment over the TA particularly if you have some R-Compound tires to go with it.

This is great information, I had the GTS alignment and recently switched to the TA alignment but only -2.2 camber in the front. It was very very balanced and handled great on the track. I do drive the car on the street so that's why I stayed at -2.2 on the camber.

[dmann]

IHOP
what did you go with for rear camber?

[Exhlr8n]

Here is Mark J from Woodhouse's response when I asked for my ACR-E

The standard SRT approved set up is -2.8 front and 6 for castor, we use 0 toe.
Rear -1.7 castor stays stock at .7 and we use .20 degrees total toe in.

Depending on your style the camber can vary of course so there is no one perfect set up I recommend Tom, if it was my own I know that I would lose at least .3 of the camber at both ends.

Been pretty happy with it overall, regadless of setup it always seems to have a little understeer, I did like the crisp response with -2.8 Front Camber, seems a bit less responsive, so I may go back to -2.8.

The above is Mark's response, word for word. Not mine. When he says "The Standard SRT", I believe he is referring to the SRT engineers standard or factory set up for the ACR, not a base model SRT Viper.

Several members have had success with the TA alignments specs on their Base SRT, and GTS Vipers.

[Arizona Vipers]

In reading my weekly speed secrets article it got me to thinking about my next track day outing.
My first track day in this car was with stock alignment, I noticed some understeer on the exit of some corners.
The next track day will be with the TA alignment.
Given that the numbers look vastly different it seems that i will have more oversteer with this setup.
Should i be concerned about the rear end kicking out(straights and corners) because of this more aggressive setup?

-David

Update: I should make note that this is a Gen V.

What tires are you running?

[dmann]

Stock tires.
I will be trying R888R in the spring.

[Nemesis]

If you are still having under steer problems, use a little brake to transfer weight onto the front end.

[dmann]

I'm definitely going to be working on trail braking. I wonder if the new alignment will help the car rotate easier.

[Cybermig]

The more aggressive camber (between -2.5 and -2.8 in the front) will help the car bite more in the turn-ins for sure since the angle of road to tire improves with the better geometry mid-turn. It's important to understand your baseline in one setting/mod list before you mess around with another setting/mod list otherwise it's hard to compare tweaks to each-other. Once you're able to put down consistent turn ins and turn outs on a track you're comfortable with and pretty much know usual mile-an-hour at turn-in, apex and turn-out, you get your baseline. Once the baseline is established, any changes you make and test with relative to the baseline give you your positive/negative result. Changing more than one thing (like suspension and tires) makes it harder to know what contributed to the gain/loss. For example let's say you change to an ACR alignment from a TA alignment and to an R-Compound like a R888R from the stock Corsas at the same time, it's hard to tell if your mile-an-hour increase at turn-in is caused more by better tire grip (likely the case) or by better angle of tire on the ground (also likely the case).

For me I gained incredible MPH gains through a number of turns at homestead and daytona but my baseline was TA alignement with corsas then changed to R888Rs (315s up front/345s rear) and went to ACR alignment. Both mods provided me significant "feel" improvements but it only translated to an extra 2-3mph in the turns which is significant in it's own right. It gave me the confidence at least to occasionally push 10/10ths in certain parts of the track where I'd usually go 8/10ths effort.

As stated above, if you're pushing through the turn you either need to load the front down more by braking to get more traction or simply enter the turn at a lower speed which gives you a smoother entry. You want to find that edge of grip just before you push as it gives you the fastest speed with optimal tire wear. Anything faster than that and you're usually having to disrupt your turn mechanics to get you back on track which results in less MPH.

Smooth is fast at the track.... cars like smooth movements. The cool thing about Vipers is they definitely let you know when you're driving not-smooth by introducing you to a brown underwear moment. But that's how many of us learn the limits of the car and get faster over time.

[GTS Dean]

IMO, there are only two things to consider when it comes to alignment - lap time, and tire wear. The faster you go, (up to a point) the more aggressive you can be with alignment. You want to work the tires to their individual maximum, but if you put too much camber in them, your braking will suffer and that will hurt lap times. If your front is pushing, you can always do some steering with the back tires. You may need to adjust your corner entry braking and rotation to do that. The back tires give you more usable footprint anyways.