Manual or power rack for 3G hemi

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Dartsun

Mopar Dude
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Hello I'm complemplating my next engine build for my 69 dart. I'm leaning towards a 3G hemi crate engine with a Gerst tubular k frame w/rack and pinion steering. Any of you guys running a manual rack with the hemi? How about the power rack with hemi? This is going to be a daily driver car and I'm not partial to either set-ups. Just looking for recommendations. Thanks Dustin
 
I'm running a power rack but I'm having some issues like whine from the pump and jerky steering response. Not sure if it is the rack or pump yet. Manual would have been a lot simpler and far less costly. There is a fair bit of plumbing involved with the power rack with lines between the pump. rack and reservoir. Only thing I don't know is the steering effort with manual - but someone must have done it.
Jim
 
Im going manual. It's maybe 1/2 turn more than power from lock to lock at 2.5-3. Old manual steering could be anywhere from 4-6.5 turns!
 
Maybe send a pm to tincup. I know he ran both. Started with a manual rack and switched to a power. May have some good insight on the effort beteeen the two
 
Maybe send a pm to tincup. I know he ran both. Started with a manual rack and switched to a power. May have some good insight on the effort beteeen the two

Thank you I read thru the tin cup power steering issues with the PSI being to much for a mustang rack. He got it figured out. Thank you for responses. Dustin
 
I'm running a power rack but I'm having some issues like whine from the pump and jerky steering response. Not sure if it is the rack or pump yet. Manual would have been a lot simpler and far less costly. There is a fair bit of plumbing involved with the power rack with lines between the pump. rack and reservoir. Only thing I don't know is the steering effort with manual - but someone must have done it.
Jim

What pump are you running? I've read that the GPM and not the psi is what results in a twitchy rack. Apparently the Mustang racks out of the Alter-K are meant for 700-800 and no more than 1000 psi, there were later mustang racks that were built stronger for 1350 psi but I don't believe Bill uses those. I believe this is the pump Tincup went to the trouble to run, according to them it's 1500 psi / 2 GPM. He tells me it works flawlessly. The stock hemi pump from what I found here is 1650-1750 / 2.2 GPM. I've been yet to be able to verify that, everywhere I find two very different numbers, some say the 5.7 is 1350 (no sources) and the 6.1 is 1600 (lots of sources), I'm not really sure... I'm in the process of figuring this whole thing out myself and, as I intend to run a hydroboost from a mustang, I found a quote on moparts in this thread mentioning Pete (handle: autodynamics) woes of trying to do it with too little pressure and the booster not working well. So right now it looks like I'm on the path of just using the stock pump or a 6.1 jeep pump (for the reservoir) and the Heidts PS-101 valve to lower the pressure to the rack after the hydroboost. There's also numerous people all over the web claiming to run the stock hemi pump on a stock steering box and it working fine for years. Based on all of the random contradicting info I can find, all I can say is...

Good luck!
Ryan
 
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I'm running an EPAS unit.

Steering Column.jpeg.jpg
Steering Column Fitment1.jpeg.jpg
 
Ryan
I'm using a GM Type II pump. The specs are 3 GPM flow (but no idea at what rpm) and come set up for 1200 psi, but you can lower the pressure setting with a shim kit.
Bill Reilly used a power rack from a 80-93 Mustang on my kit which is rated at 1000 psi. (ie it is not a Mustang II rack that needs 850 psi max)
Jim

IMG_4464_800x449.JPG
 
One thing to remember is that pressure is only built with resistance, so a power steering pump isn't always putting out its max pressure. You only see max pressure when you turn the steering to the lock and hold it against the stop.

Side story, but I have a 71 Vette with factory power steering and was looking at reducing the pressure because I want the steering a little heavier. Everyone was saying that it doesn't make a difference because you only see the pressure reduction at the end of the travel, so you still have light steering on center. May be why people are having lower pressure racks live for long times.
 
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