anyone know what the specs are for the factory ls series valve springs? i'm talking everything, lm7, lq4/9, ls1/6, gen IV stuff too. there is no real info on valve springs for these motors listed anywhere. anyone have info on any aftermarket ones too? i'm looking for these figures specifically:

at the seat/over the nose pressures
coil bind
installed height (i realize this will change one head/spring combo from another and it'll likely be easier to just measure, i'm looking for *typical* numbers though)

and one other question, will stock 5.3 valve springs control a stock 01 ls1 cam?

 

I picked up a set of L92 take-off springs (claimed they were taken off of a new crate engine that was upgraded) on eBay for something like $25. The engine builder measured them, came up with 105# seat at 1.800" installed height, 280# at 1.300" open, coil bind at 1.230". We compared them to the old 317 (LQ4) springs, I don't remember details but seat & open pressures (I hate saying that - it's "force", not pressure) were lower, and coil bind higher (the 317 springs were made from larger diameter wire, if you can believe that).

 

wow...ok, sounds like that might be a good route to go. little 5.3 with an ls1 cam is going in my little bro's car in the next few months, want to be sure it's going to be happy.

 

They may have cost more than that, but it wasn't more than $50, I'm sure.

Check out eBay item 320590576912.

 

alright, that's a solid solution for this setup. however, i would still like specs on stock springs if anyone else has that info.

 

Stock LSx springs have a paint stripe on the from the factory. Figure out what color you've got and google them (EX: orange springs LS1). GM swapped springs alot over the years and a few factory recalls changed them out too. It's hard to say without actually looking in there

 

ah, good detail to know! i had no idea about the paint stripe. i'll look at what i have and go from there

 

LS6 valve springs are cheap and will be more than adequate for most mild cams. I think these are what come with the hot-cam kit as well. You can usually find them for $50/set. They're the same springs that come on new LS3 heads. They are claimed to support .525 or .575 lift depending on what you read. My guess is that the .525 lift is based on using the larger LS3 valves, and the .575 is based on using the smaller, lighter LS6 valves. Either way, they're cheap and they're very good springs. They're easy to identify because they're yellow:

 

according to the GMPP online virtual catalog, and prices from www.gmpartsdirect.com, the LS2/LS6 springs, PN 12499224, $49.92/set, are 90# at 1.80", 295# at 1.25", and good for 0.570" while the L76/L92 springs, PN 12589774, $34.08 for 16, are also 90 at 1.8, but 264 # at 1.30", and only good to 0.520".
Can one use them safely with a 0.525" cam? I would, but I'm not telling you to try it.
I think the bigger issue is trying that cam in a 5.3L because you'll lose torque up to 3500 rpm. Switching to the common and cheaper ( used ) LQ4 cam would give better driveability and better average power, even with less peak HP. You can get them as low as $20, and they don't require a tune, or springs, so why not try that first? They actually make a better turbo cam than the '02-'04 LS6 cam when boosting a 5.3

 

i have an lq4 cam too that i could throw in there. someone tried to reinvent the wheel with this motor. i bought it cause it had the vic jr. carb intake manifold on it i'm now using on my 370. i bought the whole motor for $350. it's got a stock 5.3 shortblock, 01 ls1 camshaft, and some 317 heads on it. i'm not really sure what the guy was thinking. i'm putting my 5.3 heads on it, and camshaft selection is still up in the air as i have a stock 4.8 camshaft, an lq4 camshaft, and the ls1 camshaft. i'm not looking to put down crazy numbers with this car. it's a daily driver for my little brother. he wants it to sound good, and run atleast 13.99. magnaflow catback will handle the sounding good part, the 13.99 shouldn't be a problem based on trucks running mid 15's with basic bolt-ons that weight ~2k lbs more...

we're planning to go with the f-body ls1 intake and accessories for clearance sake, also going with stock f-body exhaust manifolds for now. out of the three cams at my disposal, what would be the better choice based on the intake/exhaust we're planning?

 

the 4.8 cam specs 191/190-114, 457/466. The 6.0 cam specs 196/207-116, 467/479. The 5.7 cam depends on year and model, but '01-'03 was same as 6.0
If you correct for rocker ratio, the valve timing events: for the 4.8 cam, installed at a 114 intake centerline, are IO 16.5 after top, IC 31.5, EO 31, EC 17 before top. The 6.0 at a 113 intake centerline is 13 after, 33, 44.5, 13.5 before. That's where I'd install them for street performance.

 

not sure how much degreeing we're going to do with this project, as that would require an adjustable chain...but knowing that the lq4 cam will be torque-y-er helps in selection. is there a way to degree in a camshaft with a stock timing chain setup?

 

No cheap way for the LSx. It's either buy a fancy chain set, or live with factory spec. But considering how bad the stock chains stretch, I feel that a good chain is an absolute necessity. Stock intake openings are already way too late to start with, and chain stretch only makes a bad problem worse.

 

I think any of those will run faster than 13.99 in a thirdgen with tires/gears. You only need 240whp to do mid low 13's on proper stalled auto setup. Stock 5.3 makes 300hp so should be already at 250-260whp.

I'd be tempted to run a LS6 or 99-00 LS1 cam since 99-00 is abit bigger than 01-02 and makes 10hp more from most of the dyno runs i've seen. LS6 is even more powerful.

 

this will be a bare bones swap with drivability in mind, but ET goals are not being thrown out the window. right now it'll be gears/tires and some small suspension mods. no converter in the budget though. no ls6 cam in the budget either. we have these three cams...one of which will go in. i'm liking the idea of low end torque in this car that the lq4 camshaft should give us.

remember i went 12.31 w/ 243rwhp/tq....a good converter goes a LONG ways...but this isn't an all-out car to do as much as possible with as little as possible. this is a driver with a few tnt nights thrown in every month.

 

yep i've done the 12.90's with 254whp, so a converter/launch will make ET

Out of those 3 cams I dont think you will notice a difference in driveability either way. may show different numbers on the dyno but I doubt your butt dyno will feel anything.

LQ4 with the extra torque is probably where i'd go. Any of the LSx springs should handle that cam. LS6 are the most popular i've seen used with most all mild cams.

 

the heads are already assembled, so if i don't have to go back into them to keep the springs happy, that would kick some serious butt. i'll be sure to upgrade the timing chain to a new stock one, since we're not going to spend any money on a double roller for this motor. this motor is just to get his feet wet. he's 19, and he's never had anything faster than a very tired lb9/auto...he doesn't need something that'll put him into a ditch like mine will.