Valve springs

I keep pounding the seats and bending the valves after a few runs, and I was wondering how much spring you guys would run on a Wedge, 25/30psi boost, 2.35 intake super alloy valve 1.90 ex, 275@.050 7.30 lift


Thanks,

 

Springs

Tell us more:
1) Engine Speed
2) Type of Rocker Assembly
3) Type of Super Charger
4) Valve Spring now being used
5) Installed spring height
6) Retainer info 10°, 8°, 7° ?

 

1.7000rpm
2.T&D shaft
3)littlefield 1471
4)nextec springs, advertised 250 at the seat but we have 300..
5)2.00 install height
6) Last I heard we were using 10 degree

Manley Nextec
Part No. Part No. Description Valve Lift O.D. I.D. Pressure ( lbs. / in. ) Bind Code
221424-16 221424P-16 Super Gas, Super Comp., .880 1.640 .860 250 @ 2.000 647 1.070 A

 

Springs

I am going to assume that you are referring to a Chrysler Wedge, and that the intake valve that you refer to as a (“2.35 intake super alloy valve), is stainless material.
That being the case the weight of the valve should be in the area of 154 grams. That is a very heavy valve to control at 9000 rpm.
Doing a little math to determine the effect of manifold pressure on the back side of the valve (2.350/2) = 1.175 (1.175 x 1.175) = 1.380 (1.380 x 3.1416) = 4.335 sq in. (4.335 x 30 psi) = 130 pounds of pressure overcoming valve spring pressure
300 pounds of seat pressure less 130 pounds of boost pressure force = 170 pounds of effective spring pressure.
The lack of spring pressure combined with the heave intake valve will produce the valve train problems that you are experiencing.
I suggest that you consider increasing the spring pressure to, a minimum of 450 pounds and if you are planning, in the future, to increase the engine speed to 10,000, I suggest a minimum of 500 pounds of seat pressure, along with a decrease in valve weight.
Look at a Manley 221449,221450

Noel Manton
951 674-2212

 

springs

I knew when Noel asked all those questions there was going to be a math Quiz !!! hi Noel....

 

Who's doing the best springs at the moment ? 526 hemi, 14-71, Manton pushrods, planning on reving to 8000 ish

 

Noel,

Thanks for your response. I should have been more clear, I have a BBF with TFS A heads, and yes Ferrea super alloy valves.

Is Titanium valves the only answer here or what is the chance of doing your suggested 450 at the seat fixing the issues? That sure sounds a little cheaper


One more thing.. Running the 300 at the seat springs Ive had no issues with running Manton 3/8 140 wall push rods. Will 450 at the seat create issues with bending push rods?