LS1 Valve Springs on 3400?

[Sorin]

Ben and I were talking about some heads with head work he might possibly have for me, and he mentioned a couple of you using LS1 valve springs. So what's that all about? What all is needed, as it's not JUST the springs is it?

Also I saw the springs for $2 each on GMPartsDirect. Go there or somewhere else, or what? These are 3400 heads.

[mfuller]

At the very minimum, you need to change the valve seals with older 3.1 VIN "T' pieces and use a LS1 spring seat since the 3400 from the factory uses integrated seats/seals and LS1 springs don't fit LA1 spring seats. You can re-use your factory retainers and locks, but depending on your mileage, you should consider replacing them with new LS1 pieces also.

[Sorin]

I don't know of the mileage on the heads, would have to ask ben. But these heads would be going on a 97 3100 with 87,000 miles.

[v6h.o.]

you need:

LS1 Springs
LS1 Spring Seats (bronze shim)
3.1L vin"T" mpfi Valve seals 6 Exhaust, 6intake (they are different)

you can reuse your old GEN3 Retainers and Locks. or use the LS1 stuff but they're basically the same part.

on gen2 heads you have to swap over the retainers and locks.

ive been running them in my engine since 2000, rev the engine up to 6500 daily with a .470 inch lift, and have never had any issues with valve float.
cheap way to do a good set of springs.

[Sorin]

So let me get this straight, just to be sure. I need the 3.1 valve seats for my 3100 engine with 3400 heads, to use the LS1 springs properly?

[1QUICKHATCH]

you need:

LS1 Springs
LS1 Spring Seats (bronze shim)
3.1L vin"T" mpfi Valve seals 6 Exhaust, 6intake (they are different)

you can reuse your old GEN3 Retainers and Locks. or use the LS1 stuff but they're basically the same part.

on gen2 heads you have to swap over the retainers and locks.

ive been running them in my engine since 2000, rev the engine up to 6500 daily with a .470 inch lift, and have never had any issues with valve float.
cheap way to do a good set of springs.

I though I was the only one that spun my car up past 6000 every day! do you have a part # for those by chance? its just easier to deal with the GM parts guys if I have a part # or else they ask for a vin # and stuff.

[v6h.o.]

So let me get this straight, just to be sure. I need the 3.1 valve seats for my 3100 engine with 3400 heads, to use the LS1 springs properly?

you need the LS1 spring seats ( the part that fits under the spring to keep the spring from eating into the aluminum)

the valve Seals are the only 3.1L part used. you need these due to the 3x00 seals/integral seat setup are too large of diameter to fit in the narrower LS1 spring.



and yes scoot. she see's that RPM EVERY day of its life. i drive my car hard, and to its limit. the powerband doesnt kick in untill 3500/4000 rpm, it used to be 6200 rpm all the time, untill i got this Holley on there and changed the rev limiter up to 6500. :P

[sharkey]

imho, its good to take them up there once in a while. it clears the carbon out. at leats thats what i tell the cops

[SappySE107]

I know 2 gen 3s that run up to 6800-7000. Are the stock LS1 springs fine or should crane springs be used?

[RacerX11]

I would go with Crane springs. I have a set of stock LS1 springs I have checked the rate on, and they aren't much better than stock 3X00. When you install them at 1.7" (vs. 1.8" LS1 installed height) they have a little more seat pressure than stock. But the rate is lower, so at max lift they are about the same pressure as stock. I will dig up the numbers later.

Marty

[SappySE107]

Cool, thanks We will have to add this info to the site.

[funky3821]

So do you need to drill out the seats? Cause I already have this whole set-up and when I did my engine dress up and new gaskets I tried to install them but the seat drill out wasn't big enought to fit over the valve post! So I decided to scrap the plan and now I have all this stuff sitting on my garage on a shelf!

I would like to do this LS1 spring swap seeing I will be having to raplce my engine in my Monte carlo (96)!

[v6h.o.]

So do you need to drill out the seats? Cause I already have this whole set-up and when I did my engine dress up and new gaskets I tried to install them but the seat drill out wasn't big enought to fit over the valve post! So I decided to scrap the plan and now I have all this stuff sitting on my garage on a shelf!

I would like to do this LS1 spring swap seeing I will be having to raplce my engine in my Monte carlo (96)!

no you dont drill anything.

[funky3821]

Ok then why is it that the ones I got don't fit over the valve post! I don't get it. Well I guess they will just collect dust and someday I will figure something out for them!

[v6h.o.]

Ok then why is it that the ones I got don't fit over the valve post! I don't get it. Well I guess they will just collect dust and someday I will figure something out for them!

im a bit confused about what you are refering to. you mean new 3X00 valve seals?

they are a tight fit over the stem yes.