2.5 shor stroke engine, my plans Options

[michel richard]

So here's what I'm doing for the engine as part of my "GT style" conversion. First and foremost, I figure that an engine in a GT style car has to be rev-happy.

So, here's what I'm putting together, with the help of my trusty wrench, Ron Green of Campbell Gararge in Montreal:

Short stoke 2.5 Porsche engine:

1) Used 7R engine case, align bored, Timeserted, shuffle pinned
2) 90 mm JE pistons, 10.5 compression ratio
3) 90 mm replated Nickasil cylinders, sourced from EBS
4) Standard piston ring set
5) 66 mm counterweighted crankshaft
6) GE 80 camshafts
7) EBS racing valve springs
8) EBS valve spring retainer set for above
9) 2.0 connecting rods
10) ARP rod bolts and nuts for above
11) twin plugged heads
12) Electromotive HPV twin ignition
13) Turbo lower valve covers
14) front mounted ol cooler with "GT Style" installation
15) new bearings and gaskets all around
16) miscelaneous engine parts, stock.

I still need to figure out what to do with the port sizes in the head. The target is to have a 8,000 rpm redline, and 250 hp, although the redline is more important than the hp to me.

So that's the plan. I pulled the trigger on the hard parts above today. ( I already have the crank and the miscelaneous parts).

Induction is going to be 40 mm PMO carbs, jetting to be determined.

I'll post to this thread as progress is mad on the engine.

Michel Richard

[TimT]

Ill mention the connecting rods again.. Porsche reinforced the bottom end of the rods when they increased displacement from 2.0 to 2.2L. Your building a high revving 2.5. You said you planned on winding this engine out to 8000rpm, stout connecting rods are a must.

Ive seen a case almost sawn in half by a broken connecting rod, it aint a pretty sight.

2.2E heads are pretty choked .. the port size is 32/32. 2.7 US& ROW heads were 35/35. I had the heads on my 2.2 opened to 38/38

Id rethink the bottom end on the engine you want to build..I think lhe last set of pauters we bought was $1400

your engine build going to cost thousands more.. and if a rod lets go youve lost your total investment