2.0 upgrade to 2.7 (2.5) question

adam911 · 03-12-2009, 11:38 AM

Can anyone tell me: Does any machine work need to be done to the 2.0 block in order to accept 2.7 cylinders, pistons and heads?

Thanks in advance

jluetjen · jluetjen's Garage

Yes. The spigots need to be opened up to fit the larger cylinders. Is this a mag 2.0 case or an aluminum 2.0 case?

adam911 · 03-12-2009, 03:36 PM

It's a 69 engine, so I believe it's a mag case.

J P Stein · 03-12-2009, 04:41 PM

The spigots need to be bored to 97mm as I recall. That gets iffy with an early 3R case.

jluetjen · jluetjen's Garage

I'd question if a mag 2.0 case is really strong enough for 2.7 liters. Porsche significantly strengthened the case by the time that they got to the 7R in order to support 2.7 liters and 210 HP. This is especially true if it's anything beyond mildly tuned. Getting the case dowel-pinned I would think would be a minimum requirement.

adam911 · 03-12-2009, 04:55 PM

Seems like it's probably more trouble than it's worth. I'll hold out for a replacement motor.

Thanks for the advice guys.

deathpunk dan · 03-12-2009, 05:59 PM

This is one of the engine upgrades mentioned in B Anderson's Performance Handbook, but I think that you'd be better served buying a rebuilt larger displacement engine and mothballing the orig for numbers matching purposes (for multiple reasons).

There's a nice 2.4e longblock on here FS right now. Rejet your existing carbs (assuming you have webers) and it's virtually plug and play! $6k is what he's asking and even going to 2.2 liters and E spec on your engine will probably cost more and result in less hp/tq than this...

Just my fairly worthless 0.02 on the matter...

kenikh · 03-13-2009, 08:08 AM

You don't want to build a 2.7 on a 2 liter case. Period. Buy a 7R case, as they are cheap.