Has anyone used these Isky springs ? Feedback requested

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Has anyone used these Isky springs ? Feedback requested

#1 Post by wikd69 » Sat Mar 12, 2011 12:43 pm

Please help me out with some feedback and advice.

After deciding these K-Motion KM-1000H springs I have are too stout for my needs I've been looking at alternative valve springs for my Darts. They need to be heavy enough to let spin this motor to around 7K yet not be so stout they'll eat my lifters on the street. Rex (Hutchison) mentioned that folks running the real stout springs on the street were getting something like 2,500 miles on a set of roller lifters. I need more life than that, even at the expense of ET or mph on the track. This thing has to be streetable and have some realistic longevity.

So, I figure I need a set of springs that can handle:

- Stainless 11/32 valves, 2.30 intake, 1.88 exhaust
- Steel retainers with 10 degree steel locks
- Up to .750 lift cam

And have the following profile:

-1.900 - 2.050 installed height
- 1.625 OD dual springs
- 240 - 275 lbs seat pressure
- 640 - 680 lbs open pressure

Most of the larger aftermarket springs I've found are way overkill for what I need, with open pressures in excess of 850 lbs. The ones I turned up with more friendly pressures yeilds are limited in cam lift.

I did find one spring from Isky that looks like it'll fit my needs along with a set of steel retainers. I'd like to know who might have used this (or similar) Isky spring and what your experience was with them.

ISKY - VALVE SPRINGS Mfr Part #: 9685

Type/Matl (Dual W/Damper, Iskyloy endurance) Color code (yellow, yellow) O. D. (1.065 1.625) I. D. (.770 1.175) Seat Pressure (240 lbs. @ 2.000) Open Pressure (685 lbs. @ 1.250) Rate per inch (550) Coil bind (1.150


Valve stem size all isky spring application 9685, 9705, 9945 inner step diam. .765 (i) outer step dia 1.165 (o) isky std. 7 deg valve lock no. n/a 5/16 11/32 3/8

Any feedback would be appreciated :)
1969 ProStreet Camaro RS Best 9.75@139 1.46 60'
Blown 427 BBC, TH400 w/Brake, Back-Half Ladderbar
Narrowed 12-Bolt, 4.10 Gears, Spool, Moser 33 Spline


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