ExitWound

I post more on PelicanParts than here, but I figured I'd give you guys a shot too since there are a lot of useful posters at the Renn. I read both forums frequently. HOPEFULLY you guys can help me too. (You're probably not familiar with the car and its rebuild, but I'll try to be brief in the history).

Took the head off the 944 and it definitely had to be cleaned and checked for flatness. After all the car has been through, I don't want any more surprises. The list is growing as I rebuild the car, sheesh.

Well, the head was checked for flatness and it's good. It was cleaned, submerged etc. The valve job is being done today. We took a gander in the factory manuals, a hayes manual, several message boards, and googlesearching and have come up empty on the information the mechanic says he needs to finish the job.

He says he requires valve spring test pressure. Without it, he can't perform the test.

This is all new to me, and I'm unsure exactly what he needs. If anyone else can help that would be great.

1986 Porsche 944 2.5L n/a

SoCal Driver

Just start checking. If you get one that is considerably out from a close average replace it.

Stem height is important. Might have to top a few of them depending on how deep the seats need to be cut.

MHT

Porsche gives you an installed height for the valve springs, the height is measured from the top of the spring base to the bottom of the retainer. This is measured with special tool 9138/1, the distance is supposed to be between 41mm and 41.5mm. There are shims that are placed under the bases to set the height. Porsche does not give a spec for seat pressure, just installed length. If your guy has a spring tester, tell him to check them all at the same height and make sure they are consistant. If he does not have the special tool he can probably check the height with a micrometer/depth gauge and a modified soft spring, or one of the inner springs. Assemble each valve, with its associated retainer and spring base and a soft spring in the head and measure the distance from base to retainer and make a note of the amount of shim needed to bring the distance into spec. The shims are available in .5mm and 1mm thicknesses, with a bit of luck you will have enough there to do the job, if the seats have not been sunk too far into the head there is not usually a need for a lot of additional shims. Good luck, I hope this is at least somewhat clear.

ExitWound

Thank you! This'll help immensely.