Guide Sleeve for Oil pressure release valve

[mike sampsel]

So my '78 did not have a guide sleeve. I will assume they are a good idea even if the original oil pressure release valve/spring did not have one?

[Flat6pac]

My PET shows it in the 78/83 with no start date. Was not in 75/77 turbo PET
I’d put it in.
Bruce

[1987 Porsche]

Just did this on my 78. You will want to order the longer spring too. Vertical.spring.

[Walt Fricke]

My 1977 gray market 2.7 had the oil system modification, so it used the longer spring, different piston, and guide tube. Maybe different external plug (different internal depth). I can't imagine the '78 SCs didn't have this.

The best way to check for the modification is when you have the case apart - does the "vented" oil from reducing the pressure dump right into the sump (old system), or go back into the intake to the pressure side of the oil pump (new system). Dempsey explains this, as does Anderson.

But Dempsey says Porsche did this modification in 1976 (my '77 came from the factory in August, 1976).

[1987 Porsche]

Walt,

Mine has the newer pistons in the picture but both springs were the smaller length and no guide tube. I thought it was odd as well so I upgraded to the longer spring and tube for the vertical one.

Lou

[Trackrash]

FWIW, my '78 did not have this from the factory. I installed the updated spring, guide, and plug during my rebuild.

There was some debate as to it's actual benefit in a thread a while back.

[mike sampsel]

Mine OEM had the newer pistons and a long and short spring. Will add the tube to the long new spring and going with “nuts” style cap, abandoning the Andre the Giant (RIP) sized screwdriver style!