Anyone have this dimension on hand? I'm trying to find some springs that will fit in the stock seat. Thanks!

 

Yer stuck with a max spring diameter around 1.30". There's a water jacket on the exhaust side that you get too close to if you go bigger or deeper.

 

Still good for hydraulic roller setups!

 

Yeah, but I'm having a hell of a time finding springs for my setup. Not many options under 1.300" OD.

 

PSI has some really good springs that you can use, and you can go up to....a pretty damn good size on the pockets...let me find the link and I'll post it up again...you can get solid roller springs in there if you want

 

https://ls1tech.com/forums/generation-iv-internal-engine/459139-machining-ls7-heads-big-springs.html


Here is that link! Pick just about ANY spring you can find! You can go really large...

Best Regards,
Adrian

 

What setup is that! How much lift and solid roller?

 

When I say I'm having a hard time, I mean I am not too sure what specs too be looking for, except for the O.D. obviously. It's a hydraulic roller, need to support .650" of lift and an XE-R lobe. I'd prefer a dual spring to help prevent valve dropping. Will LS1 aftermarket springs and retainers work? Will they clear the LS7 lash pads?

 

How about Comp 921's...that is a pretty good spring..shim to within 50 thousands of coil bind..

 

I used K-Motion k800's. Had to machine the pocket to 1.480. No problems. Springs are great and CHEAP!

 

awesome info there

 

Unfortunately I don't have the time to send the heads out to be machined, so I have to stick with a near stock spring diameter. Looking into a Crane dual spring kit right now:

O.D.: 1.275"
Coil Bind Height: 1.045"
Spring Rate: 352 lbs/in

They come with titanium retainers and the seats for $300.

 

Mike, which spring are they?

 

They are the Crane 1444832's. After further research on them, the seat pressure it only 112, which is about what a stock LS7 spring is.


Here's another option to critique. The K-Motion K-750's (dual spring):

OD: 1.265"
Seat Pressure: 130
Open Pressure: 395
Spring Rate: 482
Coil Bind: 1.050"

The retainers for them are titanium, are for 7* locks, and add .050" to the installed height. You've had good results with the K-800's, so maybe these will work too. Hopefully they won't break any intake rockers

What do you think?

 

I believe thats a single spring. Also, the 130# seat pressure is with an installed height of 1.700. That only leaves .590 or so for max lift at that installed height. If you set the installed height high enough do give you .650 lift, your seat pressure would be pretty low (less than 100 at 1.800).

What about the good ol patriot golds?

 

Oh... I didnt know 1.700" was the installed height.

As for the PP Gold's are you saying that any aftermaket LS1/6 spring will work on the LS7 heads? If that's the case, then my life just got that much easier. I was under the impression that spring in the LS7 heads should be beefy to handle the high lift and the 1.8:1 rocker ratio, so I was looking outside of just LS1 aftermarket springs.

 

If you stay under .650 lift, then yes they should work fine. The spring pocket is the same size (1.300) I believe.

I thought I read you were going to use ti valves? Are you using the gm's or ?

 

I am using GM Ti intake valves and GM sodium filled exhuast valves. The lift should be in the .620-.630" range. Perhaps the PRC dual spring kit would suit my needs. What lift are you running on your k-800's? Another quick question... Are you using LS1 valve seals? I just test fitted one on my LS7 heads and it seems to work okay.

Thanks for the help Greg, much appreciated!

 

I run .670 on the intakes, .650 on the exhaust. I am using standard ls1 viton valve seals. Nothing special there.

The PRC's would work good too.

Also something to chew on, custom thickness lash caps. Chris @ VAC Motorsports can get about any size you would need. You can get your valvetrain geometry dead nuts on that way. If its perfect with the LS7 cam (.590ish lift), it will be off on a higher lift. Cheap way of getting custom length valves.

 

Any idea if the intake valce lash cap will clear the PRC retainers? This is another worry of mine. They clear the stock LS1 retainer well.