I few months ago I realized that my pushrods where to long. 5/16 to long on the intake and 3/16 on the exhaust. I installed the correct length pushrods and replaced the lifters, but I didn't replace the valve spring. Keep in mind I drove the car with to long of a pushrod for over a year.

I noticed today, in fourth gear locked up I heard some valve clatter at 45mph, but at higher speeds and rpms i hear nothing. I only have 10.5 to 1 compression and I'm using 93 octain.

Do you think the excessive pushrod length hurt the valve springs?

I have Twisted Wedge G1 heads ported and polished by TEA in Bowling green,KY. And they have the biggest valve spring that Trickflow has for the this head, max lift is .555 and I have 528, 528 lift cam.

I went to the dyno last weekend in Nashville and the car only made 287 at the wheels, but as soon as it hit 5900 rpms the hp curve start to spiking up and down. One problem was I maxed out my duty cycle on the 24lb injecters running 101% duty cycle, so we know I need at least 30's if not 36's With the set-up I have I should be making at least 350 at the wheels. So I'm down 60 ponies. Can that be possible with bad valve springs?

 

If you're seeing spiking at higher rpms, your valves are floating and this is usually an indication that there is a problem with the springs.

 

Can you post the dyno graph?

-Alex