Last Minute Questions Before 1st Race Alignment with T1 Setup!
08-28-2012, 09:54 PM
#1
Drifting
Thread Starter
Last Minute Questions Before 1st Race Alignment with T1 Setup!
I'm looking for recommendations for alignment numbers and ride height. I've just about completed the mid-season upgrade on my '99 FRC and have an alignment booked for this Friday AM. Here's the chassis setup:
- T1 leaf springs, T1 sway bars, and T1 shocks installed (F&R).
- Phadt caster/camber plate kit & studs (F&R).
- Delrin control arm bushings (F&R).
- 18 x 10.5 Alcoa's on all corners with scrubbed 305/18 R888's
- SKF hubs with 1/8" spacers to clear the brakes (front only so far, rear is stock)
The car is driven on a fairly tight road course, typically hard on brakes - only one spot where I even get into 4th for 1/2 the front stretch. I've set the T1 rear sway bar links in the centre hole, and have zero pre-load on the adjustable end links as a starting point (all corners).
Also - does the T1 rear leaf require longer than stock bolts to get the ride height correct? If yes, does anyone have the spec for the correct bolts?
I've taken lots of pics & will update my build thread when it's done, but I'm scrambling right now to get it rolling by Friday - that's when I loose my rental garage!
Thanks in advance!
- T1 leaf springs, T1 sway bars, and T1 shocks installed (F&R).
- Phadt caster/camber plate kit & studs (F&R).
- Delrin control arm bushings (F&R).
- 18 x 10.5 Alcoa's on all corners with scrubbed 305/18 R888's
- SKF hubs with 1/8" spacers to clear the brakes (front only so far, rear is stock)
The car is driven on a fairly tight road course, typically hard on brakes - only one spot where I even get into 4th for 1/2 the front stretch. I've set the T1 rear sway bar links in the centre hole, and have zero pre-load on the adjustable end links as a starting point (all corners).
Also - does the T1 rear leaf require longer than stock bolts to get the ride height correct? If yes, does anyone have the spec for the correct bolts?
I've taken lots of pics & will update my build thread when it's done, but I'm scrambling right now to get it rolling by Friday - that's when I loose my rental garage!
Thanks in advance!
08-28-2012, 10:55 PM
#2
Le Mans Master
***Drivers weight simulated***
Camber:
-3.0* front
As much as you can get in the rear.
Toe:
Front 1/16 out
Rear 3/16 in
Ride Height:
If you're on stock bolts, go as low as you can in the front and adjust the rear from there for a good bit of rake. With our PTA cars, we run them really high in the rear. It works.
Move the rear bar to the outer most hole.
Upgrade to delrin shock and spring bolt bushings.
Camber:
-3.0* front
As much as you can get in the rear.
Toe:
Front 1/16 out
Rear 3/16 in
Ride Height:
If you're on stock bolts, go as low as you can in the front and adjust the rear from there for a good bit of rake. With our PTA cars, we run them really high in the rear. It works.
Move the rear bar to the outer most hole.
Upgrade to delrin shock and spring bolt bushings.
08-29-2012, 12:51 AM
#3
Race Director
***Drivers weight simulated***
Camber:
-3.0* front
As much as you can get in the rear.
Toe:
Front 1/16 out
Rear 3/16 in
Ride Height:
If you're on stock bolts, go as low as you can in the front and adjust the rear from there for a good bit of rake. With our PTA cars, we run them really high in the rear. It works.
Move the rear bar to the outer most hole.
Upgrade to delrin shock and spring bolt bushings.
Camber:
-3.0* front
As much as you can get in the rear.
Toe:
Front 1/16 out
Rear 3/16 in
Ride Height:
If you're on stock bolts, go as low as you can in the front and adjust the rear from there for a good bit of rake. With our PTA cars, we run them really high in the rear. It works.
Move the rear bar to the outer most hole.
Upgrade to delrin shock and spring bolt bushings.
but, you don't specify your level/run group.
I might set front toe zero unless you like a "nervous" feel to the cars turn in.
I just put a t1 spring in mine & I shortened the bolt to get the height up a little, so I don't think you'll need longer bolts (which are for lowering).
I run more rear toe in, unless you are putting down power as much as you need now.
Last edited by froggy47; 08-29-2012 at 12:53 AM.
08-29-2012, 11:20 AM
#4
Drifting
Thread Starter
Thanks for the feedback, guys! A few follow up questions.
but, you don't specify your level/run group.
I run in IP in the CACC, like IT in SCCA except we can do more upgrades to the brakes.
I might set front toe zero unless you like a "nervous" feel to the cars turn in.
Thanks, I'll take that into consideration.
I just put a t1 spring in mine & I shortened the bolt to get the height up a little, so I don't think you'll need longer bolts (which are for lowering).
I run more rear toe in, unless you are putting down power as much as you need now.
So, more power more toe in? The LS1 is stock other than a Honker intake, stock gears.
***Drivers weight simulated***
Camber:
-3.0* front
As much as you can get in the rear.
Any caster suggestions?
Toe:
Front 1/16 out
Rear 3/16 in
Are those toe numbers total, or per side?
Ride Height:
If you're on stock bolts, go as low as you can in the front and adjust the rear from there for a good bit of rake. With our PTA cars, we run them really high in the rear. It works.
Is a good bit of rake an inch higher, more?
Move the rear bar to the outer most hole.
Copy that.
Upgrade to delrin shock and spring bolt bushings.
Also done, with the exception of the top front shock mounts - I thought the new T1 shocks would come with something...
Camber:
-3.0* front
As much as you can get in the rear.
Any caster suggestions?
Toe:
Front 1/16 out
Rear 3/16 in
Are those toe numbers total, or per side?
Ride Height:
If you're on stock bolts, go as low as you can in the front and adjust the rear from there for a good bit of rake. With our PTA cars, we run them really high in the rear. It works.
Is a good bit of rake an inch higher, more?
Move the rear bar to the outer most hole.
Copy that.
Upgrade to delrin shock and spring bolt bushings.
Also done, with the exception of the top front shock mounts - I thought the new T1 shocks would come with something...
but, you don't specify your level/run group.
I run in IP in the CACC, like IT in SCCA except we can do more upgrades to the brakes.
I might set front toe zero unless you like a "nervous" feel to the cars turn in.
Thanks, I'll take that into consideration.
I just put a t1 spring in mine & I shortened the bolt to get the height up a little, so I don't think you'll need longer bolts (which are for lowering).
I run more rear toe in, unless you are putting down power as much as you need now.
So, more power more toe in? The LS1 is stock other than a Honker intake, stock gears.
08-29-2012, 01:03 PM
#5
Race Director
Rear toe in from zero to as much as 1/2 inch total toe in to put power down (more toe puts more power down during dynamic suspension change) depends on tires, track, driver inputs. Set to your liking. More toe will wear the tire more, so less for street, more for race.
Some even go more than 1/2 inch total, but I never have.
Some even go more than 1/2 inch total, but I never have.
09-01-2012, 02:49 PM
#6
Drifting
Thread Starter
Post Alignment Update
Well, it's done - thanks for the input. 
Short version, the car had been hit in a previous life and that ended up limiting the range of adjustment due to side to side discrepancies. Not sure how normal that is for these cars, or if it's actually a result of the previous accident. But c'est la vie. It still turned out ok, I think.
We set the height to 4-4.5" at the rails with a slight rake (the 305's on the fronts kept me from lowering the front any more), he checked the affect on the front toe by lowering the car and suggested that if I wanted to make some track adjustments to the front height I'd probably be ok. He used 175 lbs of ballast in the seat to simulate my weight and came up with these: 3246 lbs total (3/4 tank of fuel as well), LF: 938, RF: 905, LR: 857, RR: 819 lbs - with a 127 lb cross weight in front (not sure what that means)...
The Alignment Guy spent a good chunk of the day on it, and I got charged for 3.5 hours so I think that was very fair. He's done a ton of race cars & showed me a bunch of pics, so I think I was in good hands.
He said that if I want more rear camber, I'll have to make the LL rear a-arm mount adjustable to bring it out some. With the delrin bushings, he could only get a #5 camber plate in the LL front before the rear was binding. The RR could have had much more camber and he ended up using a #1 on that side to get the two to match, so the LR was definitely the limiting factor. Anyone done such a modification?
Thoughts & comments?
Short version, the car had been hit in a previous life and that ended up limiting the range of adjustment due to side to side discrepancies. Not sure how normal that is for these cars, or if it's actually a result of the previous accident. But c'est la vie. It still turned out ok, I think.
We set the height to 4-4.5" at the rails with a slight rake (the 305's on the fronts kept me from lowering the front any more), he checked the affect on the front toe by lowering the car and suggested that if I wanted to make some track adjustments to the front height I'd probably be ok. He used 175 lbs of ballast in the seat to simulate my weight and came up with these: 3246 lbs total (3/4 tank of fuel as well), LF: 938, RF: 905, LR: 857, RR: 819 lbs - with a 127 lb cross weight in front (not sure what that means)...
The Alignment Guy spent a good chunk of the day on it, and I got charged for 3.5 hours so I think that was very fair. He's done a ton of race cars & showed me a bunch of pics, so I think I was in good hands.
He said that if I want more rear camber, I'll have to make the LL rear a-arm mount adjustable to bring it out some. With the delrin bushings, he could only get a #5 camber plate in the LL front before the rear was binding. The RR could have had much more camber and he ended up using a #1 on that side to get the two to match, so the LR was definitely the limiting factor. Anyone done such a modification?
Thoughts & comments?
