Author Topic: 'EY' coil springs.. update  (Read 17885 times)

69Z28-RS

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Re: 'EY' coil springs.. update
« Reply #15 on: March 15, 2013, 11:59:01 AM »
I find it very difficult to believe that removing/reinstalling the same springs would make the car sit higher.   
09C 69Z28-RS, 72 B 720 cowl console rosewood tint
69 Corvette, '60 Corvette, '72 Corvette
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lynnbilodeau

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Re: 'EY' coil springs.. update
« Reply #16 on: March 15, 2013, 12:46:13 PM »
Is it possible the expansion occurred when he removed the coils ?

No it isn't possible.  The springs can't magically take on new characteristics just by being removed and reinstalled.
So... what happened?

Possible:
1.  The new ball joint was shorter (i.e. a problem solver) bringing the lower control arm up a bit.
2.  He didn't get the springs seated in the upper pocket.
3.  He didn't have it seated correctly in the lower pocket.
4.???

Measure the springs he gave you.  See if they mic at around .585 to .595.  How many coils?

NoYenko

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Re: 'EY' coil springs.. update
« Reply #17 on: March 16, 2013, 02:02:38 AM »
I have witnessed several cars where the front suspension was worked on and put back together with the same or correct  parts and the car sits higher. If it's assembled correctly, usually it is due to the rubber bushings in the control arms are preloaded (twisted) and supporting a fair amount of chassis weight. George

69Z28-RS

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Re: 'EY' coil springs.. update
« Reply #18 on: March 16, 2013, 02:07:06 AM »
Driving the car a few miles over a few bumps should allow the springs to move to their correct location, and unload the A arm bushings, and I always 'jounce' the front end a few times after assembling the suspension, or even jacking up the car, which should also do the same thing.
09C 69Z28-RS, 72 B 720 cowl console rosewood tint
69 Corvette, '60 Corvette, '72 Corvette
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55-'56-'57 Nomads, '55-'57 B/A Sedan

lynnbilodeau

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Re: 'EY' coil springs.. update
« Reply #19 on: March 16, 2013, 02:22:59 AM »
What George said.  Should have made that one number 4.  Wait until the car is fully settled to tighten upper and lower control arm bolts.

69Z28freak

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Re: 'EY' coil springs.. update
« Reply #20 on: March 16, 2013, 03:47:06 AM »
I find it very difficult to believe that removing/reinstalling the same springs would make the car sit higher.   

Crazy but true. It was drastic in my opinion!
Mike 1969 Grandma Camaro

69Z28freak

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Re: 'EY' coil springs.. update
« Reply #21 on: March 16, 2013, 03:57:07 AM »
Hi Gary sorry to keep hi-jacking your thread, but I figure why start anothet thread when we are both talking about the same thing.

Here is a pic of my front coils. I count 8 coils and a bit. 15 & a half inches long. According to the previous owner of the springs and the car they came out of,  the springs were GM NOS replacements in 2006.  The car travelled less than 1,000 miles with them and mostly sat.



Mike 1969 Grandma Camaro

69Z28-RS

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Re: 'EY' coil springs.. update
« Reply #22 on: March 16, 2013, 04:32:42 AM »
My EY springs when I removed them (after 43 yrs) were also slightly over 15" in free length, and 8-1/8 coils.. measured slightly less than 0.600 in dia of the wire.
09C 69Z28-RS, 72 B 720 cowl console rosewood tint
69 Corvette, '60 Corvette, '72 Corvette
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55-'56-'57 Nomads, '55-'57 B/A Sedan

69Z28freak

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Re: 'EY' coil springs.. update
« Reply #23 on: March 16, 2013, 04:47:11 AM »
My EY springs when I removed them (after 43 yrs) were also slightly over 15" in free length, and 8-1/8 coils.. measured slightly less than 0.600 in dia of the wire.


Sounds like we have the same springs.
Mike 1969 Grandma Camaro

69Z28freak

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Re: 'EY' coil springs.. update
« Reply #24 on: March 19, 2013, 06:26:25 AM »
Hey Gary here are my springs measured with the micrometer.

Mike 1969 Grandma Camaro

69Z28-RS

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Re: 'EY' coil springs.. update
« Reply #25 on: March 19, 2013, 04:33:09 PM »
Without having all the various springs Chevrolet used on '69 Camaros, it's impossible for me to know how they adjusted spring rate and loaded height for each car weight.   your coil wire is a bit thicker than I measured (assuming we both measured correctly and consistently), thus your spring would be for a heavier weight car.  As you see from the 69 Camaro Usage Chart, there were a lot of different springs, for the multitude of engines they offered in the camaro. 
http://www.camaros.org/images/pages/chassis/69_spring_ID_PA34.jpg

For the Z28, only the following springs were used depending on the additional front end weights for your optional items:

12437     302 Eng. Z28)
0-68                       YF
69 -148                   EY
Over 148                 YH

My car's options totaled between 76 and 107 lbs (from the factory) where the EY spring would be correct, and that was what the original springs were labeled.  If your spring coil wire dia is thicker then it may be the YH spring (for the heaviest of addon weight ranges).   You can check the weight charts to see what options might have added up to the 148 lbs (Plus) to justify the YH spring?  From the charts, it seems it would require a Z28 to have almost ALL the possible options to reach the YH level of spring, certainly it appears the tape player would be required,and that's a rare option.

09C 69Z28-RS, 72 B 720 cowl console rosewood tint
69 Corvette, '60 Corvette, '72 Corvette
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55-'56-'57 Nomads, '55-'57 B/A Sedan

69Z28freak

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Re: 'EY' coil springs.. update
« Reply #26 on: March 20, 2013, 12:18:29 AM »
Without having all the various springs Chevrolet used on '69 Camaros, it's impossible for me to know how they adjusted spring rate and loaded height for each car weight.   your coil wire is a bit thicker than I measured (assuming we both measured correctly and consistently), thus your spring would be for a heavier weight car.  As you see from the 69 Camaro Usage Chart, there were a lot of different springs, for the multitude of engines they offered in the camaro. 
http://www.camaros.org/images/pages/chassis/69_spring_ID_PA34.jpg

For the Z28, only the following springs were used depending on the additional front end weights for your optional items:

12437     302 Eng. Z28)
0-68                       YF
69 -148                   EY
Over 148                 YH

My car's options totaled between 76 and 107 lbs (from the factory) where the EY spring would be correct, and that was what the original springs were labeled.  If your spring coil wire dia is thicker then it may be the YH spring (for the heaviest of addon weight ranges).   You can check the weight charts to see what options might have added up to the 148 lbs (Plus) to justify the YH spring?  From the charts, it seems it would require a Z28 to have almost ALL the possible options to reach the YH level of spring, certainly it appears the tape player would be required,and that's a rare option.



Thanks Gary that is great info. I will check out the link you posted.
Mike 1969 Grandma Camaro

firstgenaddict

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Re: 'EY' coil springs.. update
« Reply #27 on: March 25, 2013, 07:32:05 PM »
Mike,
If those were the ones out of the black RS Z they were NOS with tags on them when they were installed. I remember they had the correct YF part number.
James
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Steve Shauger

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Re: 'EY' coil springs.. update
« Reply #28 on: March 25, 2013, 11:44:12 PM »
Hey Gary here are my springs measured with the micrometer.




Just an FYI, but the original springs in my 69 rs/z28 measure .609 as well
Steve Shauger
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69Z28freak

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Re: 'EY' coil springs.. update
« Reply #29 on: March 26, 2013, 07:37:56 AM »
Mike,
If those were the ones out of the black RS Z they were NOS with tags on them when they were installed. I remember they had the correct YF part number.

Yes, James they are the the front coil springs out of that car. I have several parts from that car going into my car soon.
Mike 1969 Grandma Camaro