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SPEEDY57TUB
January 6th 2003, 18:17
:D My friend asked me the following question and I told him I would ask the forum to get some feedback. He has a VW based Speedster car (like mine except it is flared and has all wheel Porsche disc brakes). He likes my 2110-cc but he wants to check into other configurations (I guess he wants to be different). His question is the following:

-What are the performance differences between the 2110-cc (82-mm x 90.5-mm), 2176-cc (78.4-mm x 94-mm), and 2017-cc (78.4-mm x 90.5-mm) engine configurations? I could only comment on the 82-mm stroke since I have yet to build a 78.4 stroke engine. He plans to use a new case, “ported and polished” 044 42-mm x 37-mm heads with dual springs, counterweighted crank, H-beam or I-beam rods (what rod length can be used to maintain “stock size” engine width and with the least amount of clearancing?), dual 44 IDFs, 122/125 Webcam cam and lifters, stock rockers on solid shafts, 911 adjusters, Aircooled.net Al pushrods or chromoly, 30-mm oil pump, slightly lightened 8-dowelled flywheel (for fast road car what weight is recommended?), 9.25-9.5 C/R, full assembly balance, Stage-1 or 2 KEP clutch, chromoly gland nut, 1-5/8” header and performance muffler with 1-5/8” heater boxes, and German parts throughout.
What he wants is a “snappy”, “sporty”, good revving, all around performer for his lightweight replica. He does not know what cooling system he wants, but he might go with my 911-shroud design. He is the kind of guy who likes to be different for the sakes of being difference! Please let me know what you guys have tried and like.

As for me, I'll use my 2110-cc until I can go to a Type 4 whereas my bud wants to use his Type 1 parts. Everyone is definitely different but that is what makes us interesting!


:cool:

lightning bug
January 6th 2003, 20:08
The Speedster replica is kinda light isn't it? That car should fly with a 2110. Stroker with thick cylinder walls. I can't comment on all of the specs though. It varies from engine to engine. The lightened flywheel will definitely aid in throttle responce and that "snappyness" off the line. I had 44 IDF's on my 1776 and they had to be jetted. These carbs were originally made for Fiats. They're used on VW's b/c they are the closest match. Once jetted the car ran like a bear. Good Luck!

kdanie
January 7th 2003, 12:00
Shorter strokes promote "Revyness". Longer strokes build torque but at high rpm the piston speed can be a problem. Longer strokes also require longer rods to prevent excess pressure on the piston skirts. Long stroke + longer rods = wider engine.
ken