Your thoughts on my engine findings

[Ho Hum 74]

OK, so I'm not getting any traction on the engine re-build forum with this so I'll post here:

Hi all,

Some of you know I'm rebuilding my 2.7 engine. Well the reason it's apart is because the number 3 big end rod bearing failed.

The engine has the '76 style oil pump but does NOT have the oil bypass mod performed on the case. What is the impact of this with the newer style pump?

I sent the case in to be cleaned and while it was there they removed the oil relief pistons. I noticed that the pistons are the 'new' type that Wayne mentions in his book i.e., they do NOT have the holes in them.

Now isn't that a strange combination? Might this have contributed to my bearing failure?

So I'm thinking I'll get the oil bypass mod done and get a set of oil cam restrictor plugs (as the book recommends).

The other question I have is whether I should re-use my oil pump or go for a 964 pump. Can one buy new internals for a pump?

What are your thoughts?

Thanks

Tristan

[filou]

If i had to do what you have to do, i'll try to stay to mechanically engineered specifications. I mean, try to know what equipment had that particular engine, learn his spec. and try to replicate them, that all !!
I wouldn't not try to put BIGGERTHEBETTER kind of approches.
Porsche engines don't need that kind of upgrades !!!!
Good luck, Phil !!!!

[Early_S_Man]

Tristan,

Yes, the '76 oil pump with smaller scavenge pump, combined with no bypass mod ... sounds like a recipe for oil starvation at higher rpms!

[FenderGuy]

Tristan, one thing i have learned is not to do what others tell you to do..in advice is good but do what you want to do ..people like filou need to shut up

[Beethoven]

FenderGuy
do we really have to escort you out of the building?

[FenderGuy]

Beethhoven maybe you should own a mercedes instead of a porsche those cars are for the uncouth kind that frown upon all the uncivilized.

[Randy Webb]

Can you guys spar with eath otehr in private and let's just stick to this guy's question?

[Ho Hum 74]

Wow! Didn't know you guys were so passionate about your mods!

[Ho Hum 74]

Bumb. Come on guys this can't be that hard!

[Randy Webb]

Have you looked in Bruce A's book?? Or try posting on other forums if no answer here.

[Ho Hum 74]

Yes I have. Maybe I'll e-mail Bruce.

[jester911]

Hey ho hum,
you might try to reach out to John Walker. Others here could probably answer your question, but I don't think anyone would question JW

[chibone_914]

Go with the oil bypass mod as well as the late Carrera oil pump. Don't forget to get late style oil bypass pistons. Do not reuse the old ones as they have holes in them and won't build up pressure. The late style bypass pistons do not have holes and work just great!

Oh, don't forget the late oil sump plate. It has the extra room to clear the pick-up screen.

Good Luck!

[Ho Hum 74]

chibone_914

You probably didn't read the question properly. I DO have the late style oil pistons that's what the whole question is about!!

I have new style pistons WITHOUT the oil bypass mod. What does that mean??

Anyone?

Tristan