.454 lift too much for stock valve springs?

[Bad Sport]

If it were me I would take up HawaiiDuster on the offer. Those springs are going to be better than taking chances.

You can change them yourself as well. You should get the matching locks and retainers as well. Just my 2 cents.

 

[mischiefdart]

If the heads are not installed borrow a valve spring compressor and pull at least one off and have it checked at your installed height and open height. If they have enough seated and open pressure run them, if not change em.

 

[1973dusterkid]

This is a good thread so if you changed the springs you would run the 454 lift cam with no worrys.

 

[Bad Sport]

This is a good thread so if you changed the springs you would run the 454 lift cam with no worrys.

I run a .456 lift in my otherwise stock 318 no problems, I did install the recommend springs, retainers and locks.

 

[67Dart273]

do I really need to change my new stock springs?

borrow a valve spring compressor and pull at least one off and have it checked at your installed height and open height. If they have enough seated and open pressure run them, if not change em.

This is exactly what I was trying to get at earlier. CHECK them, you don't necessarily have to REPLACE them. I'd check at least 4 random springs. If the heads are on the engine, you'll need an air fitting for the cylinder. You can remove the valve from your compression tester and use that

Then get one like this:

This has been made for years and years by KD tool. Mine was new in the early 70's

 

[eviper21]

heads are off the car, but i dont have a press or spring compressor or anything to figure out the spring rate, etc.

 

[dustoff440]

Check ebay for them I picked one up for 12 bucks new, you don't need a heavy duty one unless unless your doing lots of spring changes

 

[OldmanRick]

Well thats the thing, the heads are brand new rebuilt 973 heads. New valves, retainers, seats AND springs. As for what springs are on there?? idk but they have Zero miles on them. And since everyone is telling me to use stock 340 springs do I really need to change my new stock springs? Id just hate to waste new parts if i don't need to. Plus the few bucks to get em installed. Thanks for the links and info on the other springs tho, i definitely wasn't looking hard enough...then again i didn't know 340 springs were different / better than stock 318 springs

I posted back at #4, but after seeing two pages of this my recommedation is put'um on and run'um. The're new and your effective lift wont even be .454" so they'll be fine for all but real high R's and if you have to change them later you can just do it on the car.