Power Steering vs Manual Steering

[3rdStahl]

I am about to begin the ordering process and I am wondering about choosing Manual or power steering.
Does anyone have an opinion with either Power or manual steering. Pros and cons please
Any and all input would be greatly appreciated.

Thanks

[edwardb]

Welcome to the forum. This is talked about a lot. You'll get opinions on both sides. Here's a couple threads that discuss. As I and others point out in these threads, don't only look at the reduced effort. People make that mistake regularly. The car just plain drives better with the increased caster allowed by power steering.

https://thefactoryfiveforum.com/showthread.php?14216-Power-steering

https://thefactoryfiveforum.com/showthread.php?29327-Power-steering-or-not-Pros-and-cons

[3rdStahl]

Thanks so much

[narly1]

... As I and others point out in these threads, don't only look at the reduced effort. People make that mistake regularly. The car just plain drives better with the increased caster allowed by power steering...

Not meaning to deviate too much from the sub-forum topic but wondering what the observations have been with FFR models other than the '65 coupe, specifically the '33 Hot Rod.

I am thinking that engine displacement (mass) would be the main contributor to axle load and thus steering effort at low speed...

So maybe you'd be fine with a smaller engine?

[David Williamson]

The weight of the different models is similar and the suspension geometry is the same so power steering makes driving all of them easier. All modern cars have power steering and that is what we are used to driving.
My opinions
David W

[nskaats]

A few things that need to be considered are your physical abilities, tire size, and vehicle use. For something that's just getting cruised around with narrow front tires, manual steering is perfectly fine. For something that will have a wide front tire and see a lot of driving or hard driving, power steering is a plus.

[Jim1855]

Just a note from a different direction.

I drove 65,000 miles in a Superformance with manual steering. Cross country, city, dirt, rain, 2-lane back roads, road track and one unsuccessful attempt at Auto Cross.

Castor was somewhere in the 3-4 degrees, front tires were 275/40-17s from a variety of manufacturers and most of the driving was with a 14" steering wheel and I'm just a skinny guy. Only real high effort work was parking, once moving it was easy.

For my Challenge Car build I'm going with power steering, primarily for the increased castor and enhanced high speed stability that many have mentioned. If all I did was highway speeds I probably wouldn't be concerned but at 140-150mph track speeds I think it will help. Cobras tend to wiggle a bit at speed and high speed stability is a bit soft.

Jim

[Jeff Kleiner]

So many of you guys just aren't getting it. IT'S NOT ABOUT STEERING EFFORT, it's about what you can do with the alignment geometry which allows the car to track straighter and self center better and have increased stability at speed.

Jeff

[edwardb]

So many of you guys just aren't getting it. IT'S NOT ABOUT STEERING EFFORT, it's about what you can do with the alignment geometry which allows the car to track straighter and self center better and have increased stability at speed.

Jeff

I tried Jeff. I tried. :(

[Jeff Kleiner]

I tried Jeff. I tried. :(

I know Paul. We've both tried...over and over and over.

Jeff

[jwhit]

So many of you guys just aren't getting it. IT'S NOT ABOUT STEERING EFFORT, it's about what you can do with the alignment geometry which allows the car to track straighter and self center better and have increased stability at speed.

Jeff

could you give spec on caster from pwer vs non power ,i have both racks i got the manual in right now but i could switch to power if perfered
thanks

[Indy Shu]

3 deg vs 7-8 deg for pwr

[edwardb]

Factory Five has it in the build manuals near the end under "Finishing Touches":

For a car using a manual steering rack … use the following specifications:
Caster: 3 degrees
Camber: -0.5 degrees
Total Toe: 1/16” in or 0.14 degrees in

For a car using power steering use the following specifications:
Caster: 7 degrees
Camber: -0.5 degrees
Total Toe: 1/16” in or 0.14 degrees in

[3rdStahl]

Okay so i understand you say you can get better front end alignment. Please explain how that a manual unit cant do what a P/S Unit can adjust to.
Thanks

[edwardb]

Okay so i understand you say you can get better front end alignment. Please explain how that a manual unit cant do what a P/S Unit can adjust to.
Thanks

The increased caster (from 3 to 7-8 degrees) would make it very difficult to turn without power assist. Honestly, this is well trodden ground. The manual setup works. Many will tell you it's fine and it is. The power setup is nice too, and having had and driven both extensively, one I highly prefer. Wouldn't do another build without power steering. I suspect (fire suit zipped shut for incoming flames...) many who don't think it's a big improvement haven't driven one of these with well set-up power steering. Also because they only focus on effort and while a little stiff at low speeds or parking, once at speed effort is very manageable. In fact one of the secrets to a good power steering setup in these cars is to manage the boost. Too much isn't good. But there isn't much more to be said than what has already been said in this thread and the linked threads. Every builder needs to decide for themselves. But (hopefully) for the right reasons.

[jwhit]

Factory Five has it in the build manuals near the end under "Finishing Touches":

For a car using a manual steering rack … use the following specifications:
Caster: 3 degrees
Camber: -0.5 degrees
Total Toe: 1/16” in or 0.14 degrees in

For a car using power steering use the following specifications:
Caster: 7 degrees
Camber: -0.5 degrees
Total Toe: 1/16” in or 0.14 degrees in

i see now said the blind man 4 degrees is a lot more that would make big difference ,without sounding stupid would it be correct if you set manual steering to 7° that steering would seem slow at lower speeds but feel ok and higher
or is that a bunk ?
thanks again

[freds]

i see now said the blind man 4 degrees is a lot more that would make big difference ,without sounding stupid would it be correct if you set manual steering to 7° that steering would seem slow at lower speeds but feel ok and higher
or is that a bunk ?
thanks again

My experience with my 818S build where I de-powered the rack was that initially the car was skittish and a bit scary to drive. I added caster until it tracked very acceptably. Didn't notice any increased difficulty at low speeds or parking.
I don't think there is downside to adding caster to the manual wheel alignment.
fred

[Logan]

Setting the caster at 7+ degrees without any kind of power assist will make it very difficult to turn the wheel at all, particularly at low speeds. High caster basically means you need some power assist. Whether that’s pure hydraulic, pure electric, or an electric pump driving a hydraulic rack.... whatever you decide.

Best driving characteristics = high caster needed
High caster = power steering needed
Power steering needed = problem solved! Check the box on the order form :)

[edwardb]

My experience with my 818S build where I de-powered the rack was that initially the car was skittish and a bit scary to drive. I added caster until it tracked very acceptably. Didn't notice any increased difficulty at low speeds or parking.
I don't think there is downside to adding caster to the manual wheel alignment.

fred

Hard to evaluate without any angle numbers. I'm betting you were still well under what we're calling high caster where PS is needed. There is downside to too much without assist. Really hard to turn the wheel. :eek:


Setting the caster at 7+ degrees without any kind of power assist will make it very difficult to turn the wheel at all, particularly at low speeds. High caster basically means you need some power assist. Whether that’s pure hydraulic, pure electric, or an electric pump driving a hydraulic rack.... whatever you decide.

Best driving characteristics = high caster needed
High caster = power steering needed
Power steering needed = problem solved! Check the box on the order form :)

Exactly right. Good post. Want high caster? Add assist. It's not complicated.

Anyone who wants to dig deeper, including beyond what's discussed in this forum, there are lots of articles and videos that explain front end alignment including caster. Just Google it. This article from Tire Rack is decent. https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=4. Partial extract:

"...Caster angle settings allow the vehicle manufacturer to balance steering effort, high speed stability and front end cornering effectiveness.

Increasing the amount of positive caster will increase steering effort and straight line tracking, as well as improve high speed stability and cornering effectiveness. Positive caster also increases tire lean when cornering (almost like having more negative camber) as the steering angle is increased.

What's the downside to positive caster? If the vehicle doesn't have power steering, a noticeable increase in steering effort will be felt as positive caster is increased..."

[freds]

Setting the caster at 7+ degrees without any kind of power assist will make it very difficult to turn the wheel at all, particularly at low speeds. High caster basically means you need some power assist. Whether that’s pure hydraulic, pure electric, or an electric pump driving a hydraulic rack.... whatever you decide.

Best driving characteristics = high caster needed
High caster = power steering needed
Power steering needed = problem solved! Check the box on the order form :)

I wouldn't immediately go all the way up to 7 degrees. It can be done + 1 degree at a time. There is no absolute "correct" value to lock in, merely a "best value for your car and your driving situation".
My coupe is currently set slightly less than 3 and it feels fine to me, but I've only driven it 250 miles. I have 245/40R17 tires in front.
fred

[Jeff Kleiner]

And now for our next topic...EFI or carbureted? ;)

Jeff

[chargerbill]

This is a natural question that most of us have when putting an order together.
There are two parts to it as well.
Do you physically need power steering?
Would you prefer increased steering performance?
Answer these two questions and then make a judgement.

I called FFR to review my order before submitting (I know changes can be made after the order).
FFR made only one recommendation. Upgrade to power steering. It's even recommended in an FFR video.
I then researched the forum and upgraded.

https://www.youtube.com/watch?v=AplPHykVx0Q

[G-Pete]

And now for our next topic...EFI or carbureted? ;)

Jeff

...and to make that a 200 post thread --- what motor oil? hahahaha