[18920]

Hello,

I am interested in using a set of 6.1L valve springs on my 2013 5.7L Challenger so I can use a 6.4L cam in the engine. I understand that all 16 springs used from the 6.1L are all exhaust valves. Are shims required and if so which valve springs get the shims (intake, exhaust, or both), and how thick are the shims?

 

[Dodgeguy]

I would think if shims are needed they could be varying sizes. Usually with hydraulic lifters they need to be at 0 valve lash.So you would use a shim that gets you to that spec. for each valve.Not sure if it is a cold or hot spec.

 

[18920]

I am scrapping the cam change... too much hassle, and now I have to buy more stuff to make it work because I cant use the 6.1L springs. Got swindled there when I bought them last year. I am just going to throw on a set of headers, a fastman TB, and a K&N filter then dyno tune it.

 

[williams rt]

I am scrapping the cam change... too much hassle, and now I have to buy more stuff to make it work because I cant use the 6.1L springs. Got swindled there when I bought them last year. I am just going to throw on a set of headers, a fastman TB, and a K&N filter then dyno tune it.

Those mods will not net you any hp for the money either. Texas house of hemi has been getting 60 hp out of the 6.4 cam change.

 

[18920]

HHP contacted me and has a set of manley valve springs, retainers, and isolators for $550.

You are right, I am just going to have to pony up the cash for the manley springs and do the cam swap in order to see some real power gains. I only need the spring kit and I can start working on it. I have the headers (BBK shorty), 6.4L cam, Fastman TB, InTune, and K&N filter.