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bore and stroke?

Jesh

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Joined
Nov 12, 2009
Messages
282
Location
Soldotna, Alaska
so first question. got a 91' galant GSX its a 4G63 block, but are there any differences between the VR4 block and the GSX? if not i could use that and build it and do a swap. second question... from what i've read you have to do some grinding on the block to make a 4G64 crank to fit. is that true? and i've also heard that there is a 100mm stroke crank and a 102mm stroke crank. um... which one do i use? i know you have to get stroker pistons. and also what do you guys think of making a stroker? i know that they lose a little bit of reliability, but i'm more interested in the power potential. any feedback would be appreciated, thanks
 

prove_it

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Jul 3, 2008
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4,201
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Sioux Falls, SD
Wow I can't believe no one has ever talked about this before...........
 

belize1334

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Nov 18, 2003
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3,317
Location
Bozeman, MT
just do a search for "stroker" and you'll learn all about the options. Also, google "dsm stroker" and there's plenty more info out there.

Some quick info to get you going.

The Galant GSX has a 4g63 just like a VR4 or DSM. The only difference is the pistons and perhaps the knock sensor. All 4g63 motors have 88mm stroke and 85mm bore (from factory). For a 6-bolt, there are two OEM cranks that fit: 88mm 4g63 and 100mm 4g64/g4cs. 102mm is not 6-bolt. If using a 100mm stroke crank you have to grind the main-caps a little so the crank clears. There are other cranks out there but they're aftermarket (for better or for worse) and they aren't cheap. Magnus makes 88mm, 92mm, and 100mm. Price tag is $1600. MAPerformance sells Eagle cranks for 88mm and 100mm. They're about $700 each. OEM 88mm and 100mm are usually cheaper but you have to find one.
 

Jesh

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Joined
Nov 12, 2009
Messages
282
Location
Soldotna, Alaska
so the 4g64 100mm crank is still a six bolt? i only ask because i have a spec flywheel and would really rather not buy another flywheel.
 

Struc

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Nov 24, 2008
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Oconomowoc, WI
They come in either 6-bolt or 7-bolt, just like the 4G63
 

belize1334

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Nov 18, 2003
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3,317
Location
Bozeman, MT
^^ Correct. If you get a 4g64 crank you'll want to make sure that it is a 6-bolt as they are available in both styles. Also, the differences extend beyond just the number of bolts. Fly-wheels aside, a 7-bolt crank WILL NOT work in a 6-bolt block.
 

Jesh

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Joined
Nov 12, 2009
Messages
282
Location
Soldotna, Alaska
thanks guys, good info, exactly what i needed to know /ubbthreads/images/graemlins/smile.gif
 

Rausch

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Joined
Dec 21, 2004
Messages
12,049
Location
Cleveland, OH
Quoting prove_it:
Wow I can't believe no one has ever talked about this before...........

Very helpful.
 

Jesh

Well-known member
Joined
Nov 12, 2009
Messages
282
Location
Soldotna, Alaska
so just curious, when you buy a stroker crank, rods and pistons as a set. is it a given that it was balanced? or does it just depend on the business?
 
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