Adjustable Rear Spring Perch

Suspension, including wheel, tire and brake.
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jeffball610
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Location: Las Vegas, NV

Adjustable Rear Spring Perch

Post by jeffball610 »

I'm having trouble finding any info on spring perches for the stock rear 510 location. I know someone has done it, but I can't even find good info on spring size. From what I can gather, the stock rear springs are about 4.25" OD and about 3" ID. The suspension kit I ordered 10 years ago from Top End Performance is no longer available, but works pretty well so far. I need to adjust the rear just a bit due to my Z31 spindle swap I did.

I've searched for perches, but info seems thin from what I've done so far. There are some kits for 5" springs and lots for the common 2.5" springs most of us run on the front struts. Does anyone have a decent source in the states? I'm trying to get this resolved before this weekend 6/3/17 so I can make the most of my first autocross event in the car.
1972 Datsun 510
7-bolt 4G63T, EVO 9 pistons & rods, Garrett GT2971R, "Flipped" Stock Intake Manifold, Toyota R154, Z31 R200 w/ CVs
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jeffball610
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Joined: 15 Sep 2006 14:12
Location: Las Vegas, NV

Re: Adjustable Rear Spring Perch

Post by jeffball610 »

This is what I'm currently looking at, but it states it's for 5" or 5.25" springs. It also says it has a 2.75" ID which would probably be too tight for a 3" ID spring.

http://www.speedwaymotors.com/AFCO-Adju ... 49203.html
1972 Datsun 510
7-bolt 4G63T, EVO 9 pistons & rods, Garrett GT2971R, "Flipped" Stock Intake Manifold, Toyota R154, Z31 R200 w/ CVs
Three B's Racing
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Re: Adjustable Rear Spring Perch

Post by Three B's Racing »

jeffball610 wrote:I'm having trouble finding any info on spring perches for the stock rear 510 location. I know someone has done it, but I can't even find good info on spring size. From what I can gather, the stock rear springs are about 4.25" OD and about 3" ID. The suspension kit I ordered 10 years ago from Top End Performance is no longer available, but works pretty well so far. I need to adjust the rear just a bit due to my Z31 spindle swap I did.
Drop the rear crossmember enough so the rear springs are loose at top then install a thick rubber spacer to fit your needed height adjustment with hole in the middle to clear the bodys spring stay. You'll need to slice from the hole to the outside diameter so you can slip it in without having to remove the spring. I did this with .25" hard rubber mat we use at work to raise the back almost a 1/2" easy.
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deano510
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Location: NorCal

Re: Adjustable Rear Spring Perch

Post by deano510 »

We used something like this on our '98 One Lap of America 2dr. We used it to adjust the weight BTW the on track weight and over the road weight. Send me you email and I'll send you some pics of it. We used stock 510 rear springs and called them "weight jackers".

Please use my email below.
Dean
gzentas510@outlook.com
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jeffball610
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Re: Adjustable Rear Spring Perch

Post by jeffball610 »

I found some weight jackers on Ermish Racing. The name is misleading, but seems to serve the purpose. I don't think it's cost effective to spend $400 on a system like this, so I've decided against it. Eventually I'll do coilovers, but I was hoping to find something more cost efficient for the time being.
1972 Datsun 510
7-bolt 4G63T, EVO 9 pistons & rods, Garrett GT2971R, "Flipped" Stock Intake Manifold, Toyota R154, Z31 R200 w/ CVs
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fivetengarage
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Joined: 28 Dec 2005 11:37
Location: San Leandro,CA

Re: Adjustable Rear Spring Perch

Post by fivetengarage »

Check out the Design Products Racing setup.It's half the price of Ermish setup and says it will work with stock springs.
http://www.dpracing.co/datsun-510-rear-suspension-1
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Byron510
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Re: Adjustable Rear Spring Perch

Post by Byron510 »

The DP pn 234-1008 works well. It's a replica of what the original BRE cars used, and exactly the same design that's been in my 510 since 1971. At that price it's a pretty good buy. If you like your current spring rate, you may not even go to coil overs if you've got this set up. And if your auto crossing or tracking you can corner weight the car perfectly with these installed.

Byron
Love people and use things,
because the opposite never works.
Danthewire
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Re: Adjustable Rear Spring Perch

Post by Danthewire »

Try some roundy round places like Howe, Port City , Lefthander etc.
Coleman Racing #20801 Weight Jack swivler $41.98
We used them when I raced late models.
Dan
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ray23
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Location: Temecula, Ca

Re: Adjustable Rear Spring Perch

Post by ray23 »

sorry to hijack this thread, Byron I recently bought the weight jacker from Don, I know I forgot what he suggested as far as spring height and weight. any info would help.thanks in advance.
Ray
72 Datsun 510 2 door
86 Ford F250 extra cab 6.9 turbo Diesel 2WD
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ray23
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Location: Temecula, Ca

Re: Adjustable Rear Spring Perch

Post by ray23 »

also the car will be mainly used for street and occasional canyon runs. wheels are 205/50/15. thanks again
Ray
72 Datsun 510 2 door
86 Ford F250 extra cab 6.9 turbo Diesel 2WD
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funwithmonkeys
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Re: Adjustable Rear Spring Perch

Post by funwithmonkeys »

You will want to match them to the front springs. I have weight jacked in my car. I have 300lb front and 1100lb rear. You should match them at a ratio of 3.8 or as close as you can get.
If no one from the future comes back to stop you from doing it then how bad of a decision can it really be?
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ray23
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Re: Adjustable Rear Spring Perch

Post by ray23 »

whats the length of the springs, currently my fronts are 200Lbs (UNK brand) 8" 2.5" ID springs the back I'm trying to figure out what length i should go with. I'm planning on buying a complete set maybe from Eibach, just don't know how long of a spring I should order. thanks!
Ray
72 Datsun 510 2 door
86 Ford F250 extra cab 6.9 turbo Diesel 2WD
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Fred_L-P
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Location: Montreal, Can

Re: Adjustable Rear Spring Perch

Post by Fred_L-P »

I have 250lbs 8" x 2.5"ID Eibach in the front and for the rear I bought a 500lbs 18" x 3"ID Eibach truck spring that I cut in half, so ~1000lbs 9" springs. I will need to buy weight jack kit because it sits too low for me.
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MikeY
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Re: Adjustable Rear Spring Perch

Post by MikeY »

I'm sure is a little hillbilly. I cut a donut out of plywood to put above the stock rubber. 5/8 th thick to get Andy at specialtys springs to the right height.
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funwithmonkeys
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Re: Adjustable Rear Spring Perch

Post by funwithmonkeys »

ray23 wrote: 14 Sep 2018 10:31 whats the length of the springs, currently my fronts are 200Lbs (UNK brand) 8" 2.5" ID springs the back I'm trying to figure out what length i should go with. I'm planning on buying a complete set maybe from Eibach, just don't know how long of a spring I should order. thanks!
If you are planning on running the weight jackers the springs mine has on it are 6" I could fit an 8" in there though.
200lb fronts are a bit light if you are planning on any autoX. You will find yourself running out of travel and hitting the bump stops. I know I did even on the street.
If no one from the future comes back to stop you from doing it then how bad of a decision can it really be?
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