Isky 9945 springs
03-25-2004, 12:30 AM
#1
TGO Supporter
Thread Starter
Join Date: Jul 2003
Location: Grand Rapids, MI
Posts: 4,803
Likes: 0
Received 0 Likes
on
0 Posts
Car: Z28
Engine: Sb2.2 406
Transmission: Jerico 4 speed
Axle/Gears: Ford 9" 3.60
Isky 9945 springs
Here are the specs on the cam:
Lifter/Cam type: Solid Roller (Comp custom grind)
duration @ .050": 242/254°
Lift with 1.5 rockers: .571/.583"
Lobe Seperation: 113°
The valve springs i was GOING to run, isky 9945. here are the specs:
Type: Dual w/ Damper
OD/ID: 1.625/.770
Seat pressure: 250lbs @ 2.020
Open Pressure: 675lbs @ 1.270
Spring rate: 550
Coil Bind: 1.180
max lift: .750
Looking at other common springs that are recommended by comp, these appear to be a spring AND a rev kit. My main question is this. Are the 9945 TOO strong for street use. like will these wear down so fast that im replacing them every so often?
http://www.iskycams.com/pdfcatalog/PAGE45.pdf
The other 2 that im considering are the 9965 and 9975. Would either of these be a wiser choice? also, if i get the 9945's (well replace the ones i have), would i have to run longer valves?
Lifter/Cam type: Solid Roller (Comp custom grind)
duration @ .050": 242/254°
Lift with 1.5 rockers: .571/.583"
Lobe Seperation: 113°
The valve springs i was GOING to run, isky 9945. here are the specs:
Type: Dual w/ Damper
OD/ID: 1.625/.770
Seat pressure: 250lbs @ 2.020
Open Pressure: 675lbs @ 1.270
Spring rate: 550
Coil Bind: 1.180
max lift: .750
Looking at other common springs that are recommended by comp, these appear to be a spring AND a rev kit. My main question is this. Are the 9945 TOO strong for street use. like will these wear down so fast that im replacing them every so often?
http://www.iskycams.com/pdfcatalog/PAGE45.pdf
The other 2 that im considering are the 9965 and 9975. Would either of these be a wiser choice? also, if i get the 9945's (well replace the ones i have), would i have to run longer valves?
03-25-2004, 06:32 AM
#2
Supreme Member
Join Date: Jul 1999
Location: Loveland, OH, US
Posts: 18,457
Likes: 0
Received 15 Likes
on
15 Posts
Car: 4
Engine: 6
Transmission: 5
Those are just dual springs with damper. A rev kit is a big assembly thing that goes under the head, and has some springs that push down on the top of the lifters; it is not part of, and does not directly involve, the valve springs.
Note that those are 1.625" OD. There aren't alot of heads that you can cut the spring pockets out that big, because they'll overlap the head bolts. They're for heads with the intake valves relocated outwards from the stock location. Also, note that the pressures are given for a 2.02" installed height; the stock height on a SBC is 1.70" - 1.75", so even with .200" longer valves you will have trouble getting enough height.
With anything like a normal valve and stud location, the biggest spring you can usually run is 1.55" OD.
Their pressures and spring rate would be OK, a little beyond need most likely, but they would work as far as that goes. I just don't think you'll have much fun getting them to fit. They look more like big block springs.
That catalog page won't come up for me so I can't comment ont he other 2 part #s.
You should look for a 1.55" srping that gives 200-225 lbs at 1.80" and around 500 at .575", and will support .650" without coil bind.
Note that those are 1.625" OD. There aren't alot of heads that you can cut the spring pockets out that big, because they'll overlap the head bolts. They're for heads with the intake valves relocated outwards from the stock location. Also, note that the pressures are given for a 2.02" installed height; the stock height on a SBC is 1.70" - 1.75", so even with .200" longer valves you will have trouble getting enough height.
With anything like a normal valve and stud location, the biggest spring you can usually run is 1.55" OD.
Their pressures and spring rate would be OK, a little beyond need most likely, but they would work as far as that goes. I just don't think you'll have much fun getting them to fit. They look more like big block springs.
That catalog page won't come up for me so I can't comment ont he other 2 part #s.
You should look for a 1.55" srping that gives 200-225 lbs at 1.80" and around 500 at .575", and will support .650" without coil bind.
03-25-2004, 12:55 PM
#4
Supreme Member
Originally posted by Stekman
how would i calculate spring pressure at .575
how would i calculate spring pressure at .575
525(Isky 9945s) x .583 (your lift)+ 250 (seat pressure @ 2.020) = 556.08 lbs
9945s is way to much pressure for a street car
Jerry
03-25-2004, 01:40 PM
#5
TGO Supporter
Thread Starter
Join Date: Jul 2003
Location: Grand Rapids, MI
Posts: 4,803
Likes: 0
Received 0 Likes
on
0 Posts
Car: Z28
Engine: Sb2.2 406
Transmission: Jerico 4 speed
Axle/Gears: Ford 9" 3.60
How about Comps 952 Springs?
OD/ID: 1.544/.806
Max Lift: .750
Seat: 206 lbs @ 1.950"
Open: 567 lbs @ 1.250"
Spring Rate: 515 lbs/in
Bind: 1.200
I already have Super 7 locks that add .050" to the installed height. Would i be good if i mixed that with .100 valves?
according to the above calculation, thats 506.245 lbs @ .583" (502.125 lbs @ .575")
OD/ID: 1.544/.806
Max Lift: .750
Seat: 206 lbs @ 1.950"
Open: 567 lbs @ 1.250"
Spring Rate: 515 lbs/in
Bind: 1.200
I already have Super 7 locks that add .050" to the installed height. Would i be good if i mixed that with .100 valves?
according to the above calculation, thats 506.245 lbs @ .583" (502.125 lbs @ .575")
Thread
Thread Starter
Forum
Replies
Last Post
LT1Formula
Engine/Drivetrain/Suspension Parts for Sale
7
10-08-2015 08:34 PM
