RideTech Tru Turn System

[darren@ridetech]

1fastssnova,
I wish there were a simple yes or no answer to your question. But in reality there is only one way to answer that question...try it. I agree, in theory the steering arm position should be the same, so the bumpsteer #'s "should" be close. You would also want to take a look at turning radius (since the arms are shaped differently that ours) and ball joint angles.



Lets play a game..... How many combinations of control arms, spindles & springs can we put together?

[1fastssnova]

Darren,

Thanks for the reply, totally true, I did not think of the control arms possibly changing the position of the spindle in relation to the frame (closer or farther away depending on different brands' designs). I guess as people try them out with different combinations you will get the feedback to say whether or not Tru Turn will work with different combos. Really impressed with the fact that you guys came out with an option for stock subframe guys to get the same tire fitment as the aftermarket subframes.

Frank

[darren@ridetech]

Gentlemen,
Looking for some feedback on Tru Turn installations. Please let me know what controls arms, spindles, springs, engine and header combonations were used. How well the system fit...or if you had any problems.

Thanks in advance!

[1fastssnova]

Im no sales person for ridetech, but if you ditch ur front end(sell it) and start over with Ridetechs upper and lower arms, and go coilovers, and tru turn set up, you will be shocked how different the front end will be.

I have DSE upper and lower arms(have to mod the lower) ATS upper coil over mount, ridetech single adjustable coilovers and tru turn set up and WOW, so much better then before.

I actually went with a traditional spring/shock combo because a coilover in the same space makes the spring much shorter. With the Varishock adjustables and the adjustable spring height, I can get the same results, with a longer spring. To truely get the most out of a coilover setup on stock subframe, a system like DSE or Speedtech (which raises the top mount) is the hot ticket - IMO

[darren@ridetech]

I agree, on a 1st Gen Camaro, installing a coilover on a stock control/spindle setup requires a very short shock/spring setup, resulting in reduced wheel travel and ride quality.

However, when designing our lower StrongArm we dropped the lower shock mount down a tick to allow us to run a longer stroke shock. Couple this with our Tall/Drop spindles and you will have plenty of wheel travel. This is also one of the reasons that we chose to use Hyperco springs, they have a very high tensile strength which leads to smaller diameter wire and/or fewer coils compared to other springs. This allows the spring to compress much more before coil bind.

[Mayhem]

One thing that stuck out to me when I installed the kit;

In the instructions you note: "The passenger side inner tie rod is bent down to allow clearance for the pitman arm." A bit confusing considering pitman arm is on driver side attached to p/s gearbox and idler arm is on passenger side attached to frame. But you guys already knew that.

[darren@ridetech]

Good catch! Fixed.

[Mayhem]

No problem. You guys keep inventing the products that allow a 275 up front as well as significant handling improvements, and I will keep proof reading the instructions for dumb typos.

[Mayhem]

So Anvil Auto makes deep inner fenderwells in carbon fiber. Not just beautiful either they fit wider tires.

from their website;
"Replace your steel originals with lightweight, smooth carbon fiber inner fenders. They are custom made to allow for more clearance in the outer lip area which allows for lowered suspension clearance and really makes an impression when your hood is open."

For Camaro, the website only lists 1969 but they also have 67-68 as well. Would love to know if someone with more money than me could try these out and report back specifically as it relates to the new tru turn system. It will be a stretch for me to afford a set plus california sales tax and shipping. Still gotta get wheels and brakes to finish mocking it all up.

[bret]

I'll see if they can whip out a set before the optima race...

[ProdigyCustoms]

See my install review here

https://www.pro-touring.com/showthre...165#post841165

[bill fadden]

Is there any time frame on fitting the tru turn system to afx spindles. there's a lot of potential customers waiting at their computers ready to order.

[darren@ridetech]

Compiling data right now. Should have the results ready next week!

[bret]

Tru Turn compatibility evaluation

In response to many requests to determine the compatibility of our new Tru Turn system with other manufacturer’s suspension components, we have gathered and evaluated some fitment and geometry data for the following combinations.
We realize fully that this does not cover all the possible combinations. It ONLY evaluates the most likely [and requested] combinations of the Tru Turn system with other manufacturers components. We did not evaluate any aftermarket combinations with the oem Camaro steering arm because it’s length and position typically prevents the use of the wider 10” width wheel, which has been a primary requirement of most customers.
It is very important to note that we have NOT evaluated other manufacturer’s COMPLETE systems. It is very possible that their complete systems will generate better geometry data than some of the [unintended] combinations we put together below.
THAT IS WHY WE STRONGLY RECOMMEND THAT YOU USE A COMPLETE ENGINEERED AND COMPATIBLE SYSTEM INSTEAD OF TRYING TO PIECE TOGETHER A SUSPENSION SYSTEM FROM SCRATCH!!
Most manufacturers should be able to give you this level of geometry evaluation on their own suspension systems.

Data summary:
Example A – This is a OEM spindle with an OEM steering arm…just like GM delivered it. The camber curve is nearly nonexistent, meaning that the tire will NOT lean into the turn as we would like. The toe variation @ .600” of toe IN during compression and total change @ .720” are both excessive.

Example B – This is the complete Tru Turn system as we engineered it, and as we would deliver it to a customer. The Tru Turn system shows 2.9 degrees of camber gain at a 2.5” compression position. It also shows a toe variation of only .070” [slightly over 1/16"] toe out and a total toe change of only .110” [less than 1/8"].

Example C – Substituting the SpeedTech ATS aluminum spindle within the Tru Turn system changes the camber curve little, but seems to make a dramatic increase in both max toe variation @ .540” and total toe change @ .800”.

Example D – Substituting the Heidt’s spindle in the Tru Turn system created geometry similar to example C only with even more toe variation and change.

Example E – Substituting the Heidt’s control arms for the ridetech arms did not significantly alter the geometry from example D.

Example F – Shimming the outer tie rod DOWN by .750” made a huge improvement. Max toe variation was .250”, and total toe change was .450”

Overall summary
These examples DO NOT tell us that other manufacturer’s components or systems are neccessarily inferior to the Tru Turn system. Instead they tell us that just because certain components will bolt up together, it does not necessarily mean that they will function properly together. Yes, your car will likely go down the road just fine for many years. No, a mismatched combination of parts will not offer “just as good” of handling performance as a complete system.
All the aftermarket examples showed a similar and significant improvement in camber gain. The differences seemed to be in the bumpsteer measurements. Bumpsteer is radically affected by the precise location of the various steering components. Different manufacturers will use slightly different locations for these components. When used as intended [as a complete system] they will achieve the intended goals. When combined with other [unknown] components, the end result may coincidently bolt together, but may not achieve the geometry that was originally intended.

Here is a link to more infomation on the complete Tru Turn system:

http://www.ridetech.com/store/muscle...r/tru-turn-en/

You will notice that there is some variation in the toe change data from this test to the info published on our website. This is because a bit different alignment settings were used that day...AND because it is quite difficult to measure toe to 3 decimal points over a 5 foot length.

[Bryce]

Nice write up!

[Garymac69]

Hey Bret,

I will be installing the TruTurn in a few weeks. What is the best initial settings for Camber, Caster, Toe for a car that will see 3 or 4 Autocrosses a year?

Gary

[TheJDMan]

Bret,
Just a quick question. What tire pressures have you found work best front and rear on the 48 hour Camaro?

[bret]

Hey Bret,

I will be installing the TruTurn in a few weeks. What is the best initial settings for Camber, Caster, Toe for a car that will see 3 or 4 Autocrosses a year?

Gary

I play with that stuff a lot on my Camaro, but for a [mostly] street car...I'd start with about 1 degree of negative camber, 6-8 degrees of positive caster [or as much as you can feasibly get into it], and about 1/8" of toe in. Toe can really affect how the car turns in. I've run as much as .750 toe out on a slick track where I'm trying to get the frontend to bite. That will make the car wnader around a little on the highway, but the toe is not hard to change, even at the track.

[bret]

Bret,
Just a quick question. What tire pressures have you found work best front and rear on the 48 hour Camaro?

Ahh...the elusive magic tire pressure dust! Well...every car, and certainly every tire, likes a different air pressure. I TYPICALLY start with about 26 lbs front and rear, and then start dropping if I need to to get grip and/or to balance the car out for a particular track. On a really slick autocross track I've run as low as 20psi. Make some chalk marks on your sidewalls to see if you are rolling over on them through the turns. rim width, track surface, suspension geometry and alignment all make a difference when talking about optimum tire pressures.
I always check tire pressure before every run...heat makes a huge difference....sometimes as much as 6-8 psi if you get the ttires really hot. I have seen the serious guys run nitrogen...there is likely some benefit, but I'm just too lazy to do it .

[67bird]

Correct me if I am wrong, but it almost appears as if you would need to make some steering arm changes to the other options to get the toe numbers in line with the tru-turn kit?