I just checked my valve spring installed height again and the seem to be 1.9". I'm not sure but for crane 10308-1 kit is the spring height 1.75"? It so would this be causing my hp loss at 5200 rpm (230/236EE .544). Can I just make a thicker shim to fix this problem?

Shayne

 

The tech sheet for those springs says the installed height is 1.875. You are not far off so I don't think that is contributing to the problem you mentioned.

To set them precisely, buy a set of .015s shims. Get them from Comp or Crane. That springs OD is 1.46 and the ID is .803. Most shims come in packs 15s and 30s. Mix and match for each spring to be as close as possible to the 1.875. You are using a barrel mic to measure those heights aren't you. A snap gauge is not as accurate. I understand that it is more important that the two springs per cylinder be as close to each other as possible. Get a Moroso stud mount spring compressor if you don't already have one. It will save you time and frustration on redoing those springs.

 

Thanks Don, what should I look at next if it might not be my springs? On my dyno graph it makes good power all the way to 5200 rpm(320hp) and drops off to about 300 and slowly climbs to 330 at 5900 where I let off. Could this be my lifters causing this?

Thanks Shayne

 

The problem could be a number of things. Has your PCM been dialed in for that cam? Are you using a wide band sensor on the dyno to check your O2 levels? I'm no expert here, so I might not be able to help .

 

My A/F was around 13.1 with no change at that rpm. I get some knock were my power drops but I have taken out more then 4* of timimg with know change. It makes a slight noise at 5200 rpm were the power drops off(maybe what's it causing knock).

Thanks Shayne

 

What is your total timing? Anyone local associated with a dyno shop available to be with and help.

 

My WOT timing is around 31*

 

If whatever is causing the noise is not affecting hp would the faulse knock cause a 15-20 hp drop(max knock is set at 7*)?
I hope that made sense.