hey all lost my timing chain around 6800ish rpm's and well bent all but 4 valves so i want to replace them all intake and exhaust

the heads are PRC 2.5 cnc'd 243's i called TSP and got info from them but they dont have the intake valves that they installed that are custom made to there specs that are 4.890 over all length and stock is 4.874

i can get that stock 4.874 no problem but the custom 4.890 is at least 5 weeks out so with all that said the difference is 0.016 is that going to change any thing others then spring pressure a little?

the springs on the heads are the same springs they would sell me to install on a stock 243 head (this is what i was told from TSP)

PRC 660 lift springs
1.80 installed height
160lb seat pressure
415lb open 1.15
1.015 bind

my cam is BTR LS1/2 Stage II Cam 227/234 .614"/.576" 113+2

so 660 lift springs cam on the high side is .614 should not be even close to bind

this is what is the tricky part for me

they sink the valve in the heads 0.010 then mill 0.010 off to make sure heads are flat and keep 64cc chambers so that puts the valve at 0.026 above stock height

can i use stock size manley stainless valve or should i just wait the 5 weeks? my machine shop said he feels it would be ok but should check every thing once assembled but if it was wrong it would ad a few more weeks to all this making it like 2 months plus likes an extra $200 for more valves and labor

 

Calculate how close you will be to coil bind. If you have a valve that isn't bent you can measure current installed height and then figure out how close you are. It will also change your wipe pattern on the rockers and will change the lifter preload a small amount.

The 0.660" lift on the springs really is irrelevant if they are installed with a high seat force, i.e., great compression as this will take away from lift capability when installed.