Valve Spring Comparison #1

[BogusSVO]

Valve spring comparison
BC1100 HKS Stock


The line up is (L to R)
BC1100 (NIB)
HKS Single appox 10k miles used
Stock 2G appox 140k miles Used
Kia Looked like a 4G mutant Head, ? miles Used

Used Stock 2g spring

55lbs @ 1.530

Kia used spring

58lbs @ 1.530

HKS

60LBS @ 1.530


BC1100 New

74 lbs @ 1.530



I know it is a bit unfair to check a new spring against 3 used springs.
But this is what I had on hand at the time.

 

[mitsuturbo]

I have supertech high tension duals, and I've been concerned that maybe they're TOO stiff. IIRC the shop tested them and told me they're at about 110# at installed height. This is in line with the spec supertech has posted on their site for their stiffest spring. At least i won't have to worry about valve float, but i do have concerns about the longevity of my rockers and Kelford cams with these installed.

 

[BogusSVO]

Well you are good for upper 9K RPM shifts set up for that.

The stock DSM rockers are fairly tuff , and the cams will not have issue.

My concern would be the valves, More so if you do take it to the upper rpm band a fair bit.

You running stock valves? or a decent after market stainless?

 

[mitsuturbo]

I don't remember if I'm running SI or EPN 1pc stainless valves with the kelford 272's, but i know they're a far better valve than stockers. I've had no issue revving to 8.5k, but i dont have a lot of miles on the new setup yet. Time will tell.

Edit: Also, i think it is worth noting that one of the primary reasons i NEVER run "stock" valves, is that they're a 2 piece design. Losing a timing belt is never a good thing, but better valves are a bit safer, IMO. I've yet to see a 1pc stainless valve break off and run amok like shown in your previous post about head repair. I've seen plenty of stockers break off and cause a lot more damage than what you illustrated. At least if they don't snap off, the most you're usually faced with is cracked guides along with the bent valves.

 

[prove_it]

Been there done that with some old stem cut valves I got from turbotrix back in the day. Bent 12/16 and cracked 8 guides. Didn't do squat to the pistons though, yay! Stock valves would have left some carnage.

 

[Egalloway]

Nice info.
Lets see some pics of those springs your using on my head when it makes it to you early next week Dale. Head is leaving out Monday sorry for the delay getting it down to you.