Recapping the LS1 spring swap debate

[ikessky]

So, for pre-2000 heads, we will need the following:

LS1 springs
LS1 spring seats
3.1 MPFI VIN T valve seals


For the 2000+ heads, we need to use the following:

LS1 springs
LS1 spring seats
'96+ Chrysler 318 valve seals

Is that correct? Is it also correct that we can use the stock 3100 retainers/locks?

[v6h.o.]

2000+ heads dont like the LS1 spring seats either. the Guides were changed for some strange reason, you can grind out the spring shims to fit however so they "can" work.

Im not sure what is the whole thing on the seals. i havnt yet had any in my hands to test with.

Yes you can use stock retainers and locks.

[ikessky]

Are there any special LS1 springs that are needed? I know that Comps came out with some "beehive" springs awhile back.

[v6h.o.]

Are there any special LS1 springs that are needed? I know that Comps came out with some "beehive" springs awhile back.

LS1 springs are behive or "conical" style springs. as are GEN3 springs.

you can do just stock LS1 springs they are better than stock but not by a huge amount.

[gpse3400]

Re: Recapping the LS1 spring swap debate

So, for pre-2000 heads, we will need the following:

LS1 springs
LS1 spring seats
3.1 MPFI VIN T valve seals


For the 2000+ heads, we need to use the following:

LS1 springs
LS1 spring seats
'96+ Chrysler 318 valve seals

Is that correct? Is it also correct that we can use the stock 3100 retainers/locks?

I discoverd the ChryCo '96+ 318 valve seals. They can be used for the '00+ heads that have the larger 9/16" valve guides. The Ls1 spring seats need to be drilled out to 9/16". Best to use a grinding stone.

[Froggx]

LS2/LS6 springs are a better upgrade as they are stiffer than the LS1 springs.

I am literally in the middle of the swap right now. I can't manage to get the stock spring seats / seal thing off, any suggestions for this? (Not meaning to threadjack, but I feel it would be appropriate to address this in a thread about such a swap.)

[ikessky]

Do you use the same components I listed except for the LS6 springs?

[Froggx]

Yeah, that's exactly right, everything is the same except the springs, which are the same size, only stiffer. You can't get the LS6 springs from gmpartsdirect anymore, but you can get the LS2 springs which are the exact same, only with a different part number. I'm currently installing a set on my 2000 3400. I can verify the chrysler valve seals are a perfect fit (like there was any doubt). And the spring seats should fit fine after a good grinding. The seats I got were hardened and my drill couldn't touch them, so I have to get a grinding stone. From my measurements, it appears to be actually a little less than 9/16" that it has to be ground to. I will be able to verify this last part in a few days.

[ikessky]

Excellent!!! Thanks for verifying all this info guys. I will hopefully be doing some of these swaps in the not so distant future.

[blackbombshell95]

so what are the part numbers for 3100 heads 2000 +..

with no grinding. just a perfect fitting parts wanted here.

all hardened and or SS if possible.

spring seats:
springs:
valves:
retainers:

am i missing anything

oh and rockers.'

this would be for my personal application... i will be running with a regrinded cam.
P&P heads, intakes, and TB. 3100 with 2000+ 3100 swap

if someone can give me the part numbers it would be very appreciated. I just got my Heads P&P by a friend. so now all i need is the valve train and i'm set.

[Froggx]

Valves and retainers:
Reuse stock.

Springs:
'01 LS6 Spring: 12565117 (Blue stripe)
'02 LS6 spring: 12565313 (Green stripe; Stiffer than '01 LS6 spring; If you order this spring, you will get the LS2 spring that is replacing it).
LS2 Spring: 12586484 (Replaces LS6 spring, supposedly same specs, orange stripe)

Spring Seats:
Good luck.

[blackbombshell95]

what do you mean good luck!!!! on spring seats... don't forget its an auto.

umm. maybe someone can help me out with part numbers.

i'm looking for the best combination for increased horsepower that can handle nos.

[ikessky]

Good luck as in you will need to grind out any of the spring seats that you buy.

[blackbombshell95]

Well what other combinations do i have for a better valve train???? is the LS series the best way to go for a better valvetrain??

can someone post a pic of a seat? and what how much grinding is involved. and how precise does it ahve to be.

i'm sure i can take the seats to a machine shop and have it grinded?

so i can order LS2 Spring: 12586484? any SS versions of them out? or are they SS?

and '96+ Chrysler 318 valve seals
what do i buy for a seat that i will have to regrind??

would buying aftermarket valves and retainers help out at all?

[Froggx]

You don't have to do anything to the valve seals, they fit perfectly. When I say good luck for the seats, I mean no one is able to find a part number. However, I picked up a set that fit perfectly without grinding, I'll try to find the part number for those.