View Single Post
Old 10-18-2015, 02:56 PM   #9 (permalink)
oil pan 4
Corporate imperialist
oil pan 4's Avatar
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 10,454

Sub - '84 Chevy Diesel Suburban C10
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
90 day: 141.63 mpg (US)
Thanks: 250
Thanked 3,354 Times in 2,650 Posts
Originally Posted by OilFilter View Post
I've been a little confused about the power steering system. I know what kind of output the belt driven pump is capable of, but how much does the steering box actually use in terms of flow? I know there is a lot of talk about people converting to small electric hydraulic pumps for PS, but will that work on a truck? Does a truck steering box require too much power? (29" tires)

How much power does it take? I don't know but I am going to find out here pretty soon.

Originally Posted by OilFilter View Post
Can anybody tell me what is actually required in terms of GPM? Is there any flow through the steering box when you are not turning? How much flow is required to make a turn? I would like to have some sort of hydraulic accumulator, I'm wondering if could run the steering from this for any length of time? I'm thinking part of the regenerative braking could be to recharge the hydraulic accumulator for the power steering.
A power steering pump found in Saginaw P1 and P2 pumps can make about 3gpm at idle and pump 15gpm in a P2 at 5,000rpm and 20gpm at 5,000rpm with a P1. Recirculating ball steering boxes work from 800psi to up to 1,500psi. From what I can find most OE setups are limited to less than 1,200psi.

A hydraulic accumulator will not work since the steering box bypasses fluid when there is no power assist needed to turn the wheel.
Don't believe me? Just pull the return hose off the power steering pump and start the vehicle and see what happens.
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
The Following User Says Thank You to oil pan 4 For This Useful Post:
OilFilter (10-18-2015)