refresh951

A while back, I purchased a high lift CEP cam from Spoolin51 and I have been getting the details worked out to be able to run it in my 3.1L Hybrid Stroker. The cam has a 0.525" intake lift and a 0.500 exhaust lift. This cam cannot be run in a stock setup head because there is not enough spring travel to safely accommodate the higher lift. Thus began my journey to find a spring setup that could handle the additional lift, provide good seat pressure, and be low cost After looking at a TON of options I think I have found a great, inexpensive solution.

I will be using Isky Racing Springs used in Datsun/Nissan SOHC motors. The Isky part number is 7005-8 and a set of eight cost $80

http://streetperformanceusa.com/i-15...ssan-sohc.html

The 951 stock spring cup and retainers are retained. They Isky springs provide about 0.090" more spring travel over the stock springs and result in about 140 lbs of seat pressure (about 10 lbs more the stock springs). With the high lift cam I will have 0.075" worst case to coil bind. I think these springs may turn out to be a great alternative spring setup for our motors, especially modded motors with large valves. Photos below, stock springs are on the right, Isky springs on the left.

michaelmount123

They fit the retainers and the locating cup properly? If so, great find, Shawn.

If you want even more seat pressure, just set them up closer to coil bind.

blown 944

nice find. looks like they fit well enough.

Will Feather

Looks good, I still have yet to tear down his head. But I know the springs and retainers are titanium. Probably Lindsey Racing.

refresh951

Yep, stock retainer and spring cup. Thanks for all your help along the way Michael.

Tiger03447

I don't know much about Porsche valves, but be sure to check the # of lands and grooves on the keepers to get the right ones..some valves have as many as 4 grooves in the keepers. and the keeper angle can make a difference too. Have you checked any of this out with Ed Isky Jr.? Presume that you have...good luck tiger 03447

Dougs951S

Great find Shawn, looks to be the missing piece I've been looking for to finally get my 49mm intake valve equipped head together.

Adonay

Great find was thinking of going up to 140 springs in my cylinderhead as well.
Although wont need any added lift.
I hope i can manage to shift the powerband more around 6700-6800 rpm on my 8v engine and to stay there i would feel better with a stiffer spring . Not going solid valvetrain.

MAGK944

Is it likely to cause more lifter wear just going up 10lbs on the springs or is that not even worth worrying about?

Adonay

Well for some reason Lindsey racing does not recommend more than 140# with hydraulic lifters. I guess 10 more pounds won't hurt that much. But it will increase wear slightly for sure.

V2Rocket

How are these holding up?

refresh951

Perfect thus far. About 3000 miles on them.

V2Rocket

Any reason to use these with a stock cam, other than the fact they are brand new and inexpensive?
Or just stay stock springs?

CyCloNe!

Awesome find Shawn you always seem to come up with some cool stuff for our cars.

refresh951

I will use these on any build I do. They are better all the way around.

Thanks