redbird555

iTrader: (14)

Hi all, I'm almost done gathering all the parts for my ls6 swap only thing I'm looking at is valve springs. I couldnt find real ls6 heads to go on my shortblock so i ended up getting a set of 243's off a gto. Since the valves are heavier I've had a few people tell me that the 02-04 ls6 cam coupled with the standard valves will create some bad valve train stability around the 6600 rpm redline is that true? If so what are some good budget springs (besides 918's) that I can use that will last with the ls6 cam I know usually with high lift cams springs should be changed around 30k but since this is a factory cam will they be good for longer?
Thanks Dan

Sales4@Texas-Speed

iTrader: (4)

I would recommend looking at the PAC1218 springs. We have had nothing but good luck with those, and they are pretty affordable. I would expect them to last quite awhile on your setup.

01ssreda4

iTrader: (96)

Pac +1

redbird555

iTrader: (14)

Thanks Jon I just got off the phone with Matt and he was saying the PAC 1218's were having breakage problems now? I thought it was only the 1518's that were having issues? Just so were clear though the stock ls6 springs wont work well with that redline and the heavier valves correct? Anyway those and the psi 1511 are my top choices as of now still doing a little reading.. One question though since they are stock replacement springs going on a stock cam do I need to worry about install height and shimming or should they just go on and be fine?

Sales4@Texas-Speed

iTrader: (4)

There must have been a miscommunication there because we have not had any issues with the 1218's just the 1518's. We just got a large shipment of 1218s in and I have full confidence in them.

highgear

IMHO turning 6600 rpm in a stock bottom end LS6 is asking for trouble. When I got my GM LS6 springs (made in Germany) in 2003, GM said they were good for 100K miles. The LS6 valves were longer than standard LS1, so I think you will have to run a slightly longer pushrod for a LS1 motor (heads).

redbird555

iTrader: (14)

I already have the pr issue taken care of and i dont think 6600 rpm is at all too much for that setup. that is the stock redline on all 02-04 z06s..

theevette

iTrader: (2)

I bounce off that in my z all the time 120k and all stock. I run my mobil1 and let her eat