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 Post subject: Steering Ratio
PostPosted: July 5, 2018, 10:26 am 
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Joined: July 5, 2018, 10:20 am
Posts: 6
I did a search and found many have issues with 4 turn lock to lock as a result of poor steering ration. I have a similar circumstance with a tercel rack into mk1 supra spindles (donor car). 4 turns.

As I read the solutions are:

Alternate steering rack/box
Stalker mod to the spindle arms (cut or drill?)
Howe Stealth 2:1 Steering Quickener

These seemed to be the common solutions discussed. Between 2 and 3 which is a safer option. Can the Howe Stealth Quickener really work ok with a manual steering rack?


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 Post subject: Re: Steering Ratio
PostPosted: July 8, 2018, 3:33 pm 
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Joined: July 4, 2006, 5:40 pm
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Location: Novato, CA
I've heard good things about steering quickeners, but 2:1 seems pretty dramatic.


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 Post subject: Re: Steering Ratio
PostPosted: July 8, 2018, 3:50 pm 
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Joined: June 8, 2010, 8:02 pm
Posts: 592
Location: White Rock, BC, Canada
What knuckles are you using?

Both 2 or 3 are capable of being perfectly safe if done correctly, and are capable of being dangerous if not. For steering arms, you need to have enough material to work with, and your rack position will need to be moved. The steering quickener must be mounted securely. There is a lot of load on it, and it needs to be well supported. Keep in mind your steering effort will double with a 2:1 quickener. Also you will get slightly more steering slop due to the backlash in the quickener. Cheap quickeners are best to be avoided.

2 turns lock/lock sounds good to me, but I prefer fast ratios. If you are doing a lot of street cruising, you may want a bit slower.

Cheers.

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 Post subject: Re: Steering Ratio
PostPosted: July 8, 2018, 7:25 pm 
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Joined: October 19, 2009, 9:36 pm
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Location: meadview arizona
when you say 4 turns lock to lock, how much do the road wheels turn for that amount of steering input, you may just need some lock stops on the spindles.

see how much of a turning circle you have, if it is like a London taxi then you can limit it a bit thus finding you now have 3 turns lock to lock.

if i could turn my steering another turn lock to lock then i could drive it sideways because the wheels would be at 90 degrees to the chassis, likewise if i took out 1 turn lock to lock i would need a 5 lane highway to do a "u" turn.

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 Post subject: Re: Steering Ratio
PostPosted: July 9, 2018, 7:49 am 
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We are Slotus!
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Joined: October 6, 2009, 9:29 am
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Location: Tallahassee, FL (The Center of the Known Universe)
Quote:
Can the Howe Stealth Quickener really work ok with a manual steering rack?
Wellllll, sort of... The Slotus started out life with a Mustang II manual rack and a Speedway 2:1 quickener. On the track, it was great. Quick responses, minimal input for lane changes, etc. Really nice.

Off the track, as in parking in grid or putting it on the trailer or in the garage (i.e. all the "walking pace" things) it was a b!tch to turn. Really high effort. That same gear ratio that made the inputs so minimal also made the effort really high during parking type maneuvers. HamDip sometimes just couldn't turn the wheel to pull into a grid spot.

The solution? I installed power steering. Still feels kinda heavy at slow speeds, but it works fine on-track. Honestly, I don't notice it on track but I tell myself that it makes it easier to "keep up" with busy sections like a slalom. And even HamDip can park the damn thing now.

YMMV, just my .02, etc, etc.
:cheers:
JDK

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 Post subject: Re: Steering Ratio
PostPosted: July 10, 2018, 11:11 pm 
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Joined: February 8, 2007, 4:20 am
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Location: British Columbia, Canada
Why not just get the 1.5:1 ratio quickener, rather than the 2:1 ratio quickener then?

http://howeracing.com/index.php/store/s ... 1-5-1.html

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 Post subject: Re: Steering Ratio
PostPosted: July 12, 2018, 11:13 am 
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mainlandboy wrote:
Why not just get the 1.5:1 ratio quickener, rather than the 2:1 ratio quickener then?

http://howeracing.com/index.php/store/s ... 1-5-1.html



I had read that the 1.5:1 wasn't good for manual steering, whereas the stealth was a little more durable? car is going to be about 90% trackwork and about 10% road.


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 Post subject: Re: Steering Ratio
PostPosted: July 17, 2018, 11:30 am 
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Joined: April 26, 2008, 6:06 pm
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Location: Under the weather. (Seattle)
Turns lock-to-lock is irrelevant. Inches of rack travel per turn and steering arm length from the steering axis are the important pieces of information. Is this on a build where you fear you might have a problem or a completed car where you know you have a problem? Have you considered sourcing an alternate (faster) rack?

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Last edited by Driven5 on July 18, 2018, 2:06 am, edited 1 time in total.

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 Post subject: Re: Steering Ratio
PostPosted: July 17, 2018, 4:06 pm 
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Joined: March 30, 2011, 7:18 am
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Location: central Arkansas
JCS wrote:
I had read that the 1.5:1 wasn't good for manual steering,


Well... that's probably in the context of a 3,000+ pound car with lots of kingpin inclination and caster and soft, fat tires, which is how the dirt track cars the quickeners are marketed to are set up.

A typical Locost is a long wheelbase vehicle, and with the driver so far back, you can *see* the front end change lanes before your butt and the rear wheels follow along like you're in a trailer. Conventional cars seat the driver further forward; even if that car and a Locost have the same steering quickness, the Locost will always *feel* slower to respond no matter how fast you gear up the steering. Which isn't necessarily a bad thing...


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 Post subject: Re: Steering Ratio
PostPosted: July 17, 2018, 6:11 pm 
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Joined: July 4, 2006, 5:40 pm
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I have to say the stock rack from an MGB is near-perfect on a Locost. It doesn't have a fast ratio since it was designed for no power steering, but it's plenty fast enough.


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 Post subject: Re: Steering Ratio
PostPosted: July 17, 2018, 7:11 pm 
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Joined: April 23, 2006, 8:26 pm
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De-powered Miata rack with Miata uprights: two turns lock-to-lock.

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 Post subject: Re: Steering Ratio
PostPosted: August 18, 2018, 8:48 pm 
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Joined: May 17, 2008, 10:55 pm
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Explain? Pretty certain they had more than that stock...?


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 Post subject: Re: Steering Ratio
PostPosted: August 19, 2018, 12:13 pm 
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Mid-Engined Maniac

Joined: April 23, 2006, 8:26 pm
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Location: SoCal
Well huh, you may be right, as online comments appear to indicate the power steering rack is 2.8 turns. I'll have to check and see if my rack travel is being limited, or if I'm just wrong.

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