Ok i read the sticky on the heads and here is the deal.

I have a cam i was going to be using in the camaro but i lost oil pressure cause of the pump o ring and spun a bearing(6.0 LQ9 in the works for that) and i decided since its gonna take a while and i am going to turbo the car im using this cam in the tahoe for now.

I dont want to have to buy new springs or have to hassle changing them over to the tahoe heads(aint to hard with the rope trick though). I will be changing the lifters to some newer tougher units and i already have the chrome moly stock length(for LS1) pushrods, could i use the PnP'd heads on the 5.3 as well as the rods with the stock 5.3 rockers and still gain or would i lose going from the 5.3 to the 241 casting.

The sticky said there is no gain over the 5.3 castings to the 241's so again would i come out the same or lose or possibly gain anything? Main reason is since i am changing the cam and dont want to hassle changing the springs could i just throw these on?

I hope i made some sense and if not i apolagise haha, Thanks in advance for any replys and suggestions. PLEASE dont reply telling me its just dump or stupid tell me why, i heard there is a loss but i dont see where it could be but may be understanding it wrong.

 

they flow about the same as ur 5.3 heads stock 2 stock but if there already p&pd , but you already know that ! there will be a loss in compression since the ls1 heads are 66 cc and your 5.3's are 61cc, theres were the lost in power i but if you milled about .050 then you will be just fine! and gain hp since it will put you at about 59cc, i have ls1's 853 on my lq4 and they were milled .050 ive hade no problems

 

OK thats what i was thinking about the compression and losing it there, what is the total lift of your cam with the 1.7 rocker, how close to valve to piston contact issues are ya?

You said you had an LQ4 is it built or running stock short block with the dished pistons? I just dont want to mill to get back the compression and then run into my valves hitting, my total lift wont be over .600 at @50 so should i be ok? i just dont want to have to hassle with claying the pistons and bolting everything up just to unbolt and do it again.

The loss in compression will lose a little of my torque and some hp but nothing huge id imagine. How much of a loss are we talking without milling, the LS1 valves are better than the 5.3 castings i doubt that will make up for it though by itself so will that combined with the PnP pick up the diff or do you still suggest milling?

I didnt have VtP clearance issues in the LS1 with these heads and the cam so i doubt i will on this engine due to the fact they both use a 1.7 rocker unless i mill but i dont think .50 will run me into issues whats your take?

 

my lq4 is stock short block with a 567lift cam the thing i did have to change were my pushrods hade to go down to a 7.350 as for your valve hitting the piston it wont happen your more lickly to run into your valve hanging open , but you can take care of that by putting a smaller push rod and iam runnung the stack rockers!

 

Cool i was just trying to put what i already had at it bein a cheap *** lol.

Ill talk with some shops over here to see what milling runs on the heads, were your stock rods 7.4 something length on the LQ4 thats what mine were on the 5.7 i believe.

Thanks for the info bud.

 

yeah they were 7.4 or stock there the same as ls1's