lavoy

iTrader: (2)

motor is a stock cam LS1

My first question is do i need to change the seats at all? i was reading that the ls6 seat is thicker then a ls1 seat by .015, when i bought the ls6 springs i did not get the seats with them, as i was told originally that they are a direct drop in.

second question is has any one ever noticed if the LS6 springs do indeed give you a few more usable RPMs? what i mean by this is right now my LS1 pretty much hits a air wall ( valve float i think ) around 6200, so thats where i shift, but i need to run 4th out to 6500 threw the traps so my thinking was that the LS6 springs might move that air wall up a little and i wondered if any one every tested this and took note of the max RPM difference between the springs on a stock LS1 cam? any data and help would be great i am swapping the springs in a few days, thanks guys.

blackLS1m6

iTrader: (14)

they are a direct drop in, i had them with my hotcam. i never ran it past 6200 though.

SMALLBLOCKHERO

iTrader: (2)

the installed height of the LS6 with a stock seat should be fine. it would only truly become an issue if you were worried about the coil bind. it might have a few pounds less seat pressure with the difference in thickness. i highly doubt it would matter.

lavoy

iTrader: (2)

thanks for the speedy replys, now maybe some one who can tell me if there is a rpm difference or not, the motor is turbo charged so i think the pressure behind the valve isnt helping much with float either. and its only 4th that will have to rev out, the factory limiter is moved to 6800 and i have the lingenfelter lnc-003 so i can set the spark limiter where ever i need to once i see where it ends up trapping at.

SMALLBLOCKHERO

iTrader: (2)

obviously with a higher seat pressures the control of the valvetrain will be better. your experiencing less valve float on the top thus more power ay a highr RPM. pushrod deflection will be less but i am surprised the cam even makes power above 6000 to be honest since 99 and later cams were smaller then the 97-98's. have you tried short shifting it? it might result in a faster ET but less MPH by keeping it in its optimal powerband. just my randomn thoughts here.

garygnu

with a turbo you might want to run a more stout spring.PAC 1218 or 1518.what push rods are you running?

lavoy

iTrader: (2)

yeah i can play with the shift points of 2,3 but fourth is going to have to rev out to 6500 as the car traps 135 and i am out of tire and gear options.

garygnu as stated its all stock, its only a little 500-550 whp set up, pump gas ect. the stock push rods are supposed to be the same as the LS6 ones and guys have ran super chargers and turbos on stock LS6 and LS1s with no problems at low boost, i might look into some hardened push rods but i already bought these springs and am going to run them

LilJayV10

iTrader: (39)

I am with him on this one. They aren't to pricey and damn good springs.

bearcatt

iTrader: (41)

Hi,

Yes they are a direct install but the difference is in the valve seals.

LS1 springs use valve seals without the hat while the LS6 springs use valves seals with the hat.



.

lavoy

iTrader: (2)

the springs dont care what valve seal you use, the newer ls6 style have the seat and seal as one unit, on my car the seat and seal are separate its this seat that is slightly different in height. I did end up getting the comp cam push rods and valve seals and installed the springs last night. the new comp cam seals are all viton and there is no difference between the exhaust and intake seal, i think perhaps my valve seals had been changed at some point in the past as they was all also the same no brown and black as i expected.

blackLS1m6

iTrader: (14)

my 01 ls1 had valve seals with the seat.

bearcatt

iTrader: (41)

My original LS1 853 heads had no spring seats at all, the springs sat directly on the head.



.

blackLS1m6

iTrader: (14)

Yeah the pre-01 ls1 had valve seals without seats now that i remember doing them on a 99 ls1. I think that the seal design change came out in 01.

bearcatt

iTrader: (41)

Most 2001s + should have 241 heads which are an upgrade from the 853 heads. Besides the seals with seats, the 241s flow a little better too.


.

blackLS1m6

iTrader: (14)

some 2000's also came with 241's

garygnu

any boost is extra force working against the springs.a $10000 turbo motor would like $200 springs.

bearcatt

iTrader: (41)

I wasn't aware of that, I wish I could have been so lucky.

Not that it matters anymore being that I have Livernois heads now.

GueSS Who

Think of the valve area acting as a sail with xxx pounds of pressure pushing against it.
You more spring pressure on a FI application vs a NA application.

bearcatt

iTrader: (41)

Absolutely,
Just like you mention previously, the PAC 1218 or 1518 are the way to go.
Especially the Nitrided 1518s.

lavoy

iTrader: (2)

my LS1 is a 1998 version and it had seats under the stock springs. not sure what heads it has as i never looked for the casting number, where is it located exactly?