Need some help, currently building a 4k engine and i'm suffering coil bind with my valve springs.

what set ups have people used like what spring, retainers and collets are used,and any machining that is done etc etc

 

any help would be greatly appreciated

Crow Cams 4220 double valve springs.

 

Much better solid height than stock, standard retainers and collets. 120 bucks a set delivered.

 

http://www.crowcams.com.au/media/catalogues/50.0%20Std%20Replacement%20Springs.pdf

I used Holden 202 springs with holden v8 retainers and standard 4K collets. Had to round the end of the rockers slightly to clear them into the retainers, no other machining. Works a treat with 0.474" lift and 8000rpm.

Can anyone else confirm this? And what other springs have people used with a bigger lift cam?

Like over .400". I am getting a tighe 424 grind done next week, and this is .450" lift, and i don't want to have drama's later on. I read somewhere Nissan sr20 springs have the same part number with comp cams in the USA.

Crow Cams 4220 double valve springs.

 

Much better solid height than stock, standard retainers and collets. 120 bucks a set delivered.

 

http://www.crowcams.com.au/media/catalogues/50.0%20Std%20Replacement%20Springs.pdf

 

 

Honestly; this is the best option. I'm running about .480 lift with the Crow 4220's, no problems. Direct fit.

Ok sweet, Thanks philbey. Curious, what sort of difference did you get with you cam? I know every one, and every engine is different, just curious.

I went from a 3k with a blown head gasket to a fully built, twin carb, high comp, big cam 5K.

 

Difference was AMAZING haha.

 

The cam is awesome, it's not to bad on low revs and just screams in the higher rev range. But remember, I have the whole deal here; cam, carb, extractors; COMPRESSION!

 

I'm actualy fairly limited on going to a smaller cam because of the compression ratio. It pings like mad on anything less than 98RON.

Ok, cool. Thanks. Mine will be getting increased to 10.2:1 hopefully, and jets for the 32/36 weber are on their way :happy: Extractors are another thing on my to do list, hopefully have it all ready to go at once!

Remember your comp ratio changes depending on the cam you run.

 

Definitely read up on this:

 

http://www.empirenet.com/pkelley2/DynamicCR.html

 

I'm about 11.5:1 static, but with a big cam, it's still workable. I would always advise building your motor to a DCR not an SCR!

Great information there, thank you!

a little thread digging.

 

i went down to my local crow cams with my 5k head. we tried using a double valve spring but the inner spring was rubbing on the stem seal? are you using a 3k head (o ring stem seal head) Philbey?

 

i got a valve spring from a vl with a 202 or 303 (not sure) they fit fine in my 4k head

4k vs 202/303

 

fitted to head

 

oh btw. crows P/N for valve springs with a helper spring? (it looks like a coil of flat metal) is 5038-8 and got the same rate as the doubles

They were a tight fit but not rubbing. I also noticed the inners rubbed slightly on the outers, spoke to the Crow guys and they said it's not a concern.

 

Remember that the springs increase in diameter as they're compressed, so when a free length spring slightly rubs the retainer/outer spring, it may well be clear once you've fitted it.

 

I've been running mine for over 12 months without problems.

i went to my crow cam joint today and got a 4220 double and tested fitted it to my 4k head. fits no problem

 

now a little FYI or for the faq page

 

crow 5038 single valve spring with a helper strip has a max lift of .500"

 

crow 4220 double valve springs has a max lift of .520"

 

and fit no problem, both cost $95 (if they like you)

hey guys,

 

i'm new to the whole engine build thing but i bought a 4k-c and after a lumpy cam. what cam do you guys recommend and what needs to be done once i buy the cam?? and what else do you guys recommend for more power?

any help is valuable :)

resurface the lifter $8 each

 

double valve springs $95

 

compression 10:1

 

extractors

 

port matching and intake port to be opened up

 

weber

 

 

 

THERE IS NO POINT DOING JUST A CAM! you have to do the whole lot to get decent power results.