2.5 shor stroke engine, my plans |
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2.5 shor stroke engine, my plans |
michel richard |
Dec 20 2005, 07:21 PM
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#1
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Senior Member Group: Members Posts: 1,291 Joined: 22-July 03 From: Longueuil, Québec Member No.: 936 |
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 |
kevgentile |
Dec 20 2005, 08:27 PM
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#2
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Member Group: Members Posts: 55 Joined: 14-January 05 From: gaithersburg, md Member No.: 3,448 |
8,000 is to high for a mag case. you will walk the crank right out of the case if you take it that high too many times. i have a 2.5 with much higher compression and could take it to 8,500 very easily. found no difference in power at over 8,000 then that at ~7,200, and the motor will last longer. which is a good thing when the motor cost 25,000.
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