Morit

I did search and still havent find any covincing answers... And I would prefer an answer from the guys that did a ZZ4 cam swap so they no better then the "theoretical ones"

1. What pushrods do I need..? Since I will buying for shure new ones do I buy the stock height or a bit longer or what..?

2. I will be using me friends stock heads heavely ported with "dont know what springs". What I know is that they are good for lift up to .600
and they are a bit smaller unmounted then LT4 springs (which I bought but cannot mount couse they do not fit in this heads and I cannot drill them becouse Im only borrowing them for a year or so to the time that I will be better heads blah, long one)
So do I use some retainers to have them the same size as LT4 or leave them like they are or what..?
I know a tough one

Abubaca

iTrader: (3)

I did the ZZ4 swap on my L98 with stock heads.

I'm not sure what springs will and will NOT work, but I used the LT4 spring to accomodate the .510 lift of the cam. Sorry I can't be more help on the spring issue.

You'll want screw in studs. I did NOT do this, but I wish did. Still, almost three years and I've had no problems with the press in studs that came factory.

I re-used my pushrods and lifter, being careful to make sure they went back in the same spot they came out. If you want new ones, no reason to go exotic, just get factory replacements.

I have no tuning beyond setting the timing. The car runs just great! I could probably gain some power with a tune, but it's not necessary. I don't require emmisions testing, but my buddy owns a shop and we tested it just to see and it passed with flying colors!!!!

92droptopws6

iTrader: (10)

the bad part is having a set of springs that say they are good for 600 lift,Edelbrock has a set of sure-seat springs that have this claim but they are totally JUNK that belong on a motor with 500 lift max....the Lt4 springs are not all they are cranked up to be for starters they are used in a lightweight head,lightweight sodium filled valves.so with standard weight valves the spring will be softer with RPM!!!!!
the spring you would want would be the comp cams 987 spring or the NEW beehives,screw-in studs 7/16 to avoid flex at rpm,1.6 NON self aligning,Isky guide plates,comp chromoly pushrods...the zz4 cam is a real nice cam and doing the valvetrain this way will definately optimize the cams potential even with the LESS desired head you are using..those heads will hold you back a bit even though they are ported......good luck with your build you will like the power and reliability

Morit

Well heads are really heavy, heavy ported... I wouldnt imagine how much they can be, the guy had to weld them a couple of times becouse he ported to much
I have not found any 987 springs, only lifters with that numer..
What about pushrods size..? Stock ones..?
Could you give any specific part numbers with what you said above..?
I have bought LT4 springs becouse I found on the forum that people are using them and there were no information that they have larger diameter then stock ones and dont fit stock heads :-P So I would like to be shure what to buy...

92droptopws6

iTrader: (10)

that is the number to the spring comp cams 987 dual spring 1.43 dia. the seat may need to be cut out on cast heads but NOT ON alum.
http://compcams.com/technical/Catalo...07/292-293.pdf
use stock length pushrods..

Morit

Outside diameter is 1.43 so they will not fit stock heads, and I cannot cut the heads becouse they are borrowed... LT4 springs are 1.32 but the stock heads seat diameter is 1.25' ...


Which of those would be the best for me?

Original LT4 springs aprameters are:
Description: Single Spring
Outside Diameter: 1.32"
Pressure at Installed Height: 101# @ 1.78"
Solid Height: 1.22"
Average Rate Pounds per Inch: 332

http://store.summitracing.com/partde...5&autoview=sku

http://store.summitracing.com/partde...5&autoview=sku

http://store.summitracing.com/partde...5&autoview=sku

http://store.summitracing.com/partde...5&autoview=sku

Please help, I really dont know much about heads