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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

620's or stock springs

  • Thread starter Thread starter tretz
  • Start date Start date Apr 28, 2004
T

tretz

Member
Mar 17, 2004
62
0
6
stockton, ca
Apr 28, 2004
#1
  • Apr 28, 2004
  • #1
Iv'e gathered all my parts and I'm ready to rebuild the front end on my 67. I'm going with a 1" sway bar and edelbrock shocks , should I use the 1" drop 620 springs or cut the stock coils to get the drop I want. I don't want a harsh ride. What do you recommend?
 
R

Ronstang

New Member
Apr 4, 2004
1,294
0
0
Houston Texas
Apr 28, 2004
#2
  • Apr 28, 2004
  • #2
I have had both the 620s and the 520s (which IIRC are the stock GT spec) and with good shocks (I have Konis) I prefer the way the 520s feel and handle, but this is merely an opinion. The 620s work really well to and might be better with a less race oreinted shock. Many people like then and I have installed many sets of them and all the cars rode and handled well.
 

LMan

Founding Member
Aug 10, 2002
1,246
0
0
Mom's basement
Apr 28, 2004
#3
  • Apr 28, 2004
  • #3
I have 620s and I would say that they are on the bleedin' edge for harshness on the street. If this is a concern of yours, I would recommend the 540s or equivalent.
 

skywalker

Member
Dec 22, 2003
733
0
16
Pensacola, FL
Apr 28, 2004
#4
  • Apr 28, 2004
  • #4
The diameter of the spring coil directly effects the spring rate, along with the height of the spring
 
H

hgufrin

New Member
Mar 15, 2004
39
0
0
Peoria, IL
Apr 28, 2004
#5
  • Apr 28, 2004
  • #5
I installed a 1" and the 620's at the same time. I noticed a significant handling improvement over stock (66 coupe). I am very pleased and would not even think about a different combination. The change in harshness of ridem, IMHO, is marginally but in handling, significant.
 
S

Snail50

Founding Member
Mar 24, 2001
787
0
0
Miami
Apr 28, 2004
#6
  • Apr 28, 2004
  • #6
I have a 1" front sway and 1"lowering-620's in my 67 289 coupe. I don't find the ride unpleasant at all. It's firm and competent, but not harsh, IMO. HUGE improvement over stock.
 

Hack

15 Year Member
Mar 23, 2004
1,945
13
69
Minneapolis
Apr 28, 2004
#7
  • Apr 28, 2004
  • #7
I would recommend that you do all the changes you have planned and keep your stock springs. If your ride seems mushy and you're having trouble with bottoming or something (edit: or if you want to lower the car some more), then go buy the 620, 630, whatever it takes.
 
T

tretz

Member
Mar 17, 2004
62
0
6
stockton, ca
Apr 28, 2004
#8
  • Apr 28, 2004
  • #8
ok, I made the decision, went to mustangs plus today and got the 620's and the edelbrock shocks. The edelbrock rep. was there and claimed that the combo would give me the ride I can live with, gonna take a chance and go with his recommendation. Also got talked into the shelby control arm relocation. What should I tell the alignment shop to set the front end up?
 

Hack

15 Year Member
Mar 23, 2004
1,945
13
69
Minneapolis
Apr 28, 2004
#9
  • Apr 28, 2004
  • #9
Pro-Motorsports recommends:
0 degrees camber
1/16 - 1/8 " toe in
1-3 degrees caster
 

HistoricMustang

Active Member
Apr 11, 2003
2,359
0
46
Confederate States of America
Apr 28, 2004
#10
  • Apr 28, 2004
  • #10
bump up to the 620's unless it is a daily driver.

I move up to a 780 at most road courses and up to a 1000 at Daytona and the other ovals.

I go to the dentist after each visit to the ovals.

HistoricMustang
www.historicmustang.com
 

HistoricMustang

Active Member
Apr 11, 2003
2,359
0
46
Confederate States of America
Apr 28, 2004
#11
  • Apr 28, 2004
  • #11
If you cut your springs and want to know what the new rate is go here:

www.historicmustang.com/tech.html

Check the pic with all the writing.

HistoricMustang
www.historicmustang.com
 

Max Power

Active Member
Jul 31, 2003
1,774
1
36
St Paul
Apr 28, 2004
#12
  • Apr 28, 2004
  • #12
I am running a 1-1/8th bar in front with 620s and 5 leaf mid-eye big block springs in the rear. The ride is firm but I like it that way. It's definitely live-able.

I just ordered 550 springs for my Maverick. Leafs will be a challange for that car.
 
M

Mustang67Coupe

New Member
Feb 20, 2004
64
0
0
Salem, Or
Apr 29, 2004
#13
  • Apr 29, 2004
  • #13
Hey i have old springs in my 67, but dont know the rate... I know they were used with a 428 cobra jet engine, so im guessing they are really stiff. Anyone know what rate they might be?

If i replace them sounds like 620's are the way to go
 
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