So level of assistance (or boost gain), rather than rack motion speed.
That makes sense, hydraulically.
Electric power steering pumps and hydroboost, will it work?
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That makes sense, hydraulically.
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That may be related to the capacity of the relief dump/valve/regulator or return line.
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The hydratech guy very strongly recommend that the reservoir have a pressure release valve for exactly that reason
Just got off the phone with the guys who make my steering rack (flaming river) and they said their rack operates between 700 and 1100 psi ideally, and their pumps deliver 2.5gpm flow rate so that's probably a good middle ground to shoot for.
He recommended adding a pressure reducer on the rack side of the hydroboost, since according to him hydroboost usually requires higher psi than their racks can take
Really wish I could get solid numbers on the psi/gpm the Volvo pump is rated at
The pressure reducer being on the rack side makes sense when looking at this diagram
Power Steering Gear Plumbing Diagram With & Without Hydro Boost
![Font Line Parallel Engineering Circle]()
This also shows two separate returns to the reservoir so I think that's what I'll do, probably plumb the hydroboost return to the upper remote reservoir to boot so there's ZERO chance of back pressure
Just got off the phone with the guys who make my steering rack (flaming river) and they said their rack operates between 700 and 1100 psi ideally, and their pumps deliver 2.5gpm flow rate so that's probably a good middle ground to shoot for.
He recommended adding a pressure reducer on the rack side of the hydroboost, since according to him hydroboost usually requires higher psi than their racks can take
Really wish I could get solid numbers on the psi/gpm the Volvo pump is rated at
The pressure reducer being on the rack side makes sense when looking at this diagram
Power Steering Gear Plumbing Diagram With & Without Hydro Boost
This also shows two separate returns to the reservoir so I think that's what I'll do, probably plumb the hydroboost return to the upper remote reservoir to boot so there's ZERO chance of back pressure
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You can always measure the flow and pressure...since you have the pump and sounds like you need to dial it in, anyway.
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Yeah but how to measure pressure without blowing things apart or burning the pump out
If I make a hardline loop with a gauge on it, wont that pressure burn the pump out almost immediately?
If I run it through my rack, it runs the risk of blowing seals from overpressure
And for flow, are you talking about literally just emptying one bucket of ps fluid into another with a stop watch? Won't the outflow be at insane pressure and kinda dangerous?
I was thinking of getting something like this to regulate psi from jump, some folks have used these for famously low PSI tolerant foxbody racks, but it isn't entirely clear if this is a flow restrictor or pressure restrictor
If I make a hardline loop with a gauge on it, wont that pressure burn the pump out almost immediately?
If I run it through my rack, it runs the risk of blowing seals from overpressure
And for flow, are you talking about literally just emptying one bucket of ps fluid into another with a stop watch? Won't the outflow be at insane pressure and kinda dangerous?
I was thinking of getting something like this to regulate psi from jump, some folks have used these for famously low PSI tolerant foxbody racks, but it isn't entirely clear if this is a flow restrictor or pressure restrictor
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Why are you using a Foxbody rack on a Corvette, anyway?
So you would pwm the non-trigger 12v I.e., the 80amp 12v source? With a ss relay?
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Im not sure if the flaming river steering racks are the same design as the foxbody, but the foxbody racks are known for needing very little pressure/flow rate to operate, and anything beyond that makes them heavily overboosted
Pwm on the pump from jump is an interesting idea though, I believe they have a native pwm signal? Or maybe that was a different pump
With a pwm I could install the pump inline, start it at VERY slow speed with a pressure gauge in there somewhere
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Not sure, never looked into the details. @Nmstec's board takes care of the pump speed, other pumps have PWM signal leads iirc. I still have his board sitting in a box with bigger fish to fry tight now.
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Funny how we used to put headers and glass packs on, and flip/remove air cleaner housings, to make a car LOUDER 😂
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Some info I DO have on the volvo/mazda pumps:
0-6375 RPM
Module temp limit is 110*C
Motor temp limit is 175*C
1200 PSI internal bypass
TRW type 1 Astra pumps do have around 1700psi limit, but they are not controllable. instead they use a valve on the high pressure side to raise and lower pressure.
0-6375 RPM
Module temp limit is 110*C
Motor temp limit is 175*C
1200 PSI internal bypass
TRW type 1 Astra pumps do have around 1700psi limit, but they are not controllable. instead they use a valve on the high pressure side to raise and lower pressure.
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A 1200psi bypass is encouraging, meaning I can probably use it with my current rack as a drop in and not blow it up immediately (probably), I'd still like to throw a flow rate meter and pressure meter on their for validation though
So next up is examination of the current plumbing, finding a good spot for the enclosed pump, and looking for replacement high pressure lines compatible with the existing fitting
Also need to find the model name of my current pump to see what it's rated psi/GPH is so I can match that later
Edit; actually, while a pressure gauge is easy and cheap, measuring flow is more expensive it seems. I'm lieu of that I can get one of many many used power steering analyzer kits for ~$100
So next up is examination of the current plumbing, finding a good spot for the enclosed pump, and looking for replacement high pressure lines compatible with the existing fitting
Also need to find the model name of my current pump to see what it's rated psi/GPH is so I can match that later
Edit; actually, while a pressure gauge is easy and cheap, measuring flow is more expensive it seems. I'm lieu of that I can get one of many many used power steering analyzer kits for ~$100
power steering analyzer for sale | eBay
Get the best deals for power steering analyzer at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items!
www.ebay.com
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Good news. I now support Dodge/Chrysler 12-20 EHPAS pumps. They are 1700psi @2.5 GPM.A 1200psi bypass is encouraging, meaning I can probably use it with my current rack as a drop in and not blow it up immediately (probably), I'd still like to throw a flow rate meter and pressure meter on their for validation though
So next up is examination of the current plumbing, finding a good spot for the enclosed pump, and looking for replacement high pressure lines compatible with the existing fitting
Also need to find the model name of my current pump to see what it's rated psi/GPH is so I can match that later
Edit; actually, while a pressure gauge is easy and cheap, measuring flow is more expensive it seems. I'm lieu of that I can get one of many many used power steering analyzer kits for ~$100
power steering analyzer for sale | eBay
Get the best deals for power steering analyzer at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items!www.ebay.com
Some more info on them: Support for a new, and most powerful EHPAS we’ve seen yet – NMStec
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