fastbirds

does anyone know what all has to be done to ls7 heads as far as spring pockets to accept a .700 + lift cam as far as welding to give added strength and to except an installed height of around 1.900 or 1.950.is there anyone who has been down this road that can help.

SStrokerAce

iTrader: (2)

Yep... longer valves.

fastbirds

i know you need to run a longer valve but does anyone know how much modifying needs to be done as far as welding the spring pockets.i have been told you need to add material to accept this large of a cam on the factory casting.has anyone run into this situation?thanks

383LQ4SS

iTrader: (33)

Youll have to machine the spring pockets out to 1.550 or so. Some larger springs with an OD of ~1.60+ too could be used. I have no idea how the spring pockets are on the LS7. Going to a 1.550 on a 243 casting is a delicate process but very doable.

Just be sure to plan everything in the right steps. may want to machine the pockets first before you select valve length. You may end up machining a lip for a 1.550 valve spring only partially down in the pocket...then add a shim of a smaller diameter into the original pocket..then place an ID locator over the top of those. At that point youll need quite a long valve.

But I think the LS7 stuff with its HUGE valves is ripe for a solid high lift cam. Cam lift is predicated on valve size.

Juiced

iTrader: (2)

Don't forget that by adding longer valves you are drasticly changing the the sweep andle on the rockers so you are going to need to know how much longer a vlave you are going to need so you can get your custom rockers made properly.

in my hunt for 700+ lift i founf that your going to need to go to a 1.600 spring minimum to get it, highest lift i found for a 1.550 spring was the manley next tek tool steel spring and they go to .700 lift with a 1.850/1.800 install height don't remember exactly.

SStrokerAce

iTrader: (2)

I would say if you are doing a .700+ lift SR you should be running shaft mounts anyways.

Bret

Cop Car

iTrader: (14)

these are the threads i like to see. motor builds with *****

383LQ4SS

iTrader: (33)

If i were doing something with .700+ lift I would be doing something with a 2.00 installed height. There are some 1.550 springs out there with a 2.00 installed height that should work. If you could go with a larger diameter as well too that would help.

PSI makes some springs that may with 1.50

and defiantely shaft mount and almost certainly shimmed for correct geometry.

Juiced

iTrader: (2)

i think this is better suited for shop that has lots of experiance doing high lift solid roller setups not the average joe, give Et performance, futural, or cartek a call.

MUSTANGEATER

iTrader: (10)

Don't forget the beehives!

fastbirds

it was et that i talked to a little about this and they are the ones that told me you have to weld the spring pockets to have enough support to run this big of cam.iwill call them and see if they can give me more specifics.thanks