Another high oil pressure thread

[HIGHPSI4]

I am in the process of putting my car back together and one of the issues that led to me working on it was high oil pressure. I have a 4GCS from a Galant and BSE set up. I ported the OFH when I put the engine together the first time and still had start up oil pressure well above 100psi and 5k plus rpm near 100 psi. I hogged out the relief hole more, as well as both holes leading from the front case to the oil pressure relief piston. I hope this works.

Here is another thought. I was also looking at the length of travel for the piston. The travel is limited by the short distance the spring can compress. If the piston was allow to travel further more oil could be dumpped. Cutting the compression spring would allow this extra travel. The spring engages the piston with 5/16" of the threads of the retaining cap still exposed. As the cap is turned in the spring is compressed which adds preload to the piston. Cutting the spring will not reduce the springs resistance force but would reduce preload force and allow the piston to have greater travel to dump more oil.

As of now I am going to try the OFH with just the port work but if this is not enough I will try modifing the spring.

Educated thoughts?

 

[Squirrel82]

I went from 100psi cold start to 40 from just cutting 2 coils off the spring.Balance shafts deleted.Idles at 20 warm and doesnt go past 90 once the revs get up there.This is on a 2.0 liter.

 

[HIGHPSI4]

Great! Thanks for the input.