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View Full Version : 69 c10 front steering a little to quick? bumpsteer?



Fidy6
06-02-2015, 09:06 AM
Hi guys...i have a freshly built 69 c10 with Hotchkis springs Hotchkis shocks and Hotchkis sway bars. Truck has an agr steering box. The truck has a pretty wide 275-40 tire on the front. Stock a arms and spindles....tried setting alignment as per hotchkis but couldn't get what they sent me. I think they thought i had their a arms also....but the shop got it close. Thing tracks Nice and everything it just seems very darty on the highway. First truck i had like this so i can't compare with anything. Don't know if these things have crazy bumpsteer or something ?? Anybody with some ideas would be great.
Thanx guys
Chad

bovey
06-02-2015, 05:57 PM
My suggestion would be to take it to a race shop and have a proper alignment done, forgetting about the numbers you received. I have no doubt the numbers would work if you had a complete front and back kit. The alignment needs to suit your truck.

I run basically the same set-up as you, only your parts are better, lol. My truck runs down the highway perfect and I've had it over 150 mph on tracks without issue.

bovey
06-02-2015, 06:01 PM
Just recalled someone asked me about my set-up. I contacted my shop (Can-alignment Motorsport) for his thoughts. Here is what he said about setting up my truck. I believe the 2nd and 4th line are important to your situation. Give'r.

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The camber is set to tire manufacturer recommended. -2.5

Caster has many considerations also taking into consideration not creating bump steer.

The front toe is set to maximize tire life but allow for a good turn in.

The numbers are less important but how the system works is what matters and the use of the vehicle.

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Fidy6
06-08-2015, 04:07 AM
Bovey....thanx for all the info. I definitely wouldn't feel comfy driving my truck at 150!!! When you say you have the same setup but i have better parts what do i have that's different? I don't think my parts are the "Killer" setup by any
meens.

Chad

bovey
06-08-2015, 06:19 AM
Bovey....thanx for all the info. I definitely wouldn't feel comfy driving my truck at 150!!! When you say you have the same setup but i have better parts what do i have that's different? I don't think my parts are the "Killer" setup by any
meens.

No problem. My stuff is a weird mixture of CCP, including their 1st gen drop spindles, and some really old (20 years) rear springs form a company called Christholm - they make low rider stuff and a little ECE tossed in for good measure. When I started building my truck, there were zero options - you bought the parts fast - incase it was a short run or the company went bankrupt...

IF I was to do a simple bolt on system, I'd go Hotchkis - they make nice stuff and it works. IMHO, they were the first to offer decent stuff for these trucks. I was at the SEMA show when the first did that orange short box, with almost no fan-fair, how things have changed in the past few years for the amazing. So much great stuff available now. Also, my friend runs their Phase II kit on his '79 Trans Am and it works really well - super fun to drive - everything fit very well.

AutoX_D21Hardbody
06-08-2015, 08:55 AM
My truck can become darty if the rear tire pressure is too high. I was running 32psi in the back and it was all over the place. Dropped the psi to 27 and it's much more compliant.

GEARBOXGARAGE
07-14-2015, 10:57 AM
I've got ECE 2.5" drop spindles, Hotchkis Front 2" drop springs, upper A-arms and sway bar, then out back I have a coilover setup similar to what RideTech offers with a Hotchkis "blade" style sway bar, with single adjustable QA1's all the way around. I'm also running a quick ratio steering box from ECE. It's approximately a 4.5" Front/6" Rear drop. The alignment specs that Hotchkis provides is for running their full TVS kit. You'll end up with a ton of alignment shims stacked up to get 6-9º of caster out of the factory arms, unless you relocate the lowers forward a bit. I'm running 4.5º+ Caster, 1/2º-Camber and just a bit of tow in for "spirited" street driving. Very stable and handles any local twisty road we have. It's a good starting point, but if I were to auto cross it on a regular basis, I would finish out the front with the Hotchkis lower arms and go with CPP MOD spindles so I could go with a bigger brake package. I'm running stock size cross drilled 12" rotors up front with Wilwood D-52 calipers, then the Wilwood Dynalite calipers out back with 12" cross drilled rotors also. If you'r running the Hotckis spec 6º+ caster, it will make the steering extremely responsive, almost twitchy if you are not use to it. With the factory arms running on the street, I would keep the caster down to about 5º+ or a little less and see if this helps.