Does anyone know if there are valve spring upgrades for L98 heads that can be installed without having to machine the heads?

 

there are alot of good springs from mild to fairly aggressive that will fit the L98 head pockets. But doesnt do any good when the heads only handle roughly .470 lift and near .510 with offset locks/shims. By then you have to worry about the stock press in studs from pulling out.


but few examples are the Patriot gold and extreme gold springs, they should fit in the stock pockets. AFR has 8017 springs that should fit.

Manley 22410's are a great spring that will definately fit. Comp 981's are factory spec replacements. 918 beehives will fit and are a good spring too. there are 915 beehives i believe which are lower pressure/lower lift but good for most mild hydraulic roller cams

any thing up to around 1.27 inches in diameter i think will fit. stock are 1.25 and .02 isnt that much difference. AFR's 8019's are 1.29 inch and possibly so are the extreme golds, i dont have the figures on me..but both of those springs are for very aggressive hydraulic roller cams

 

Thanks, I think i will put in a set of screw-in studs ,locks and shims

 

Manley 22410-16 springs, 23652-16 +.050" retainers, and 13091-16 locks will bolt right in and let you run up to .550" lift. You should also install 42106-16 3/8" screw-in studs as well.

 

Thanks thats great info. do i also need shims?

 

no shims- they are for worn out springs that people dont want to replace

I will get some sort of flack for that one

get some z-28 springs unless you want to be like some of the guys who have more money than research skills

 

shims are for dialing in spring pressures for the cam that will be used. if you run offset locks or retainers to raise the spring height, spring pressure falls down and may not be suitable for the cam.

Z28 springs are good for stock replacement but he said spring upgrades that fit stock heads. Z28 springs arent much of a upgrade

 

i ran tpis springs on their zz9 cam in a stock heade l98 a few years back it had .520 lift an i didnt have to do anything to the heads bolted right on .icant remember the number but i think its on their website

 

Thanks guys for the tips and advice.

 

I was looking on ebay and there was a set of z-28 springs good for 550 lift can this be right?

 

if you have an aggresive roller cam that is going to rev over 5500 then you need a spring with a heavyer seat preasure