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hi guys,<p>The T5 has a stroke of 93.8mm. IMO thats a big stroke. I was wondering if anyone knows if it is possible to swap a crank from the older models in order to decrease the stroke. I think that by doing this, the car will be more "rev-happy" and have less stress on the engine at higher rpms. With proper turbo upgrades, and cc of around 2.2-2.3L I think the engine can still product 350-400hp. I'm worried about the bottom end falling apart at higher rpms because of the long stroke. <p>Inputs please.
 

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Re: destroking the T5 (Andy's_V50)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Andy’s_V50</b> »</i></TD></TR><TR><TD CLASS="quote">hi guys,<p>The T5 has a stroke of 93.8mm. IMO thats a big stroke. I was wondering if anyone knows if it is possible to swap a crank from the older models in order to decrease the stroke. I think that by doing this, the car will be more "rev-happy" and have less stress on the engine at higher rpms. With proper turbo upgrades, and cc of around 2.2-2.3L I think the engine can still product 350-400hp. I'm worried about the bottom end falling apart at higher rpms because of the long stroke. <p>Inputs please. </TD></TR></TABLE><p>My input... you're crazy <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/smile.gif" BORDER="0"> I'm pretty sure Volvo is fairly adept with straight 5 2.5l engines...<p>UKMatt
 

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Re: destroking the T5 (Andy's_V50)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Andy’s_V50</b> »</i></TD></TR><TR><TD CLASS="quote">I'm worried about the bottom end falling apart at higher rpms because of the long stroke. <br></TD></TR></TABLE><p>Your timing belt'll snap and drive a valve through a piston long before the bottom end falls apart. <br> <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/tongue.gif" BORDER="0"> <p><TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Andy’s_V50</b> »</i></TD></TR><TR><TD CLASS="quote">With proper turbo upgrades, ... </TD></TR></TABLE><p>Keep us posted on this one. It seems up to this point without some major plumbing, a turbo upgrade is your first sticking point.<p>
 

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Re: destroking the T5 (Andy's_V50)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Andy’s_V50</b> »</i></TD></TR><TR><TD CLASS="quote">hi guys,<p>The T5 has a stroke of 93.8mm. IMO thats a big stroke. I was wondering if anyone knows if it is possible to swap a crank from the older models in order to decrease the stroke. I think that by doing this, the car will be more "rev-happy" and have less stress on the engine at higher rpms. With proper turbo upgrades, and cc of around 2.2-2.3L I think the engine can still product 350-400hp. I'm worried about the bottom end falling apart at higher rpms because of the long stroke. <p>Inputs please. </TD></TR></TABLE><p>Your post assumes "rev-happy" is "better". That long stroke is where all your low-end torque comes from. Shorten the stroke for higher RPM's (and corresponding HP) and you end up with a Japanese-ish motor (gaining power only when you wring its neck).<p>I'll take the longer stroke.<BR><BR>
<i>Modified by dneal at 10:28 PM 7-13-2006</i>
 

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Re: destroking the T5 (dneal)

the beauty of the T5 is the low end torque. I guess, it's possible, but seeing that my dealer looks at me funny for having Heico springs , Alu door pins and the typhoon system, (they don't know about the bsr) I'd probably be pushing it with a shorter crank. the turbo should then be swapped as well. seems like a nice huge project.
 

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Re: destroking the T5 (Andy's_V50)

I've read the cylinder walls are not very thick, so I think that will be your weak point if/when you plan on pushing 350+ HP.
 

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Re: destroking the T5 (Andy's_V50)

actually, i love my car when it hits 5k rpm after tuning. it kinda gets its second wind and the rpm needle shoots for the redline like a vtec...<p>
 

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Decreasing displacement is insane, IMO. If anything you want more displacement whenever possible to improve off-boost response and help with spool. <p>Invest in a larger turbo if anything.
 

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Re: (quick)

i agree. <p>the long stroke is where the engine creates its torque. if you shorten the strokes, the engine will rev easier - but without creating any torque. like italian or japanese cars. short strokes with easy high revs but ultimately lacking torque. believe me. your car won't move. <p>modding an engine is one thing. trying to change the basic working principles of an engine or trying to build another engine with different characteristics are something else. <p>i strongly suggest you don't take this road my friend. at some point we have to accept the fact that we're not all that much better than volvo engineers and technicians. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/smile.gif" BORDER="0">
 

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Re: destroking the T5 (Andy's_V50)

Without re-hashing everyone's great points.....I will say one thing:<p>"There's no replacement for displacement."<p>Even look at F1. The new V8's and limited V10's are not as fast. Granted not as much time has been spent yet in their development, but still.........
 

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Re: destroking the T5 (B5254 Style)

That's sorta true....Considering F1 went from 3.0L to 2.4L and approx. 900 HP to 700 HP they haven't slowed down THAT much.... And a lot of that has to do with continual tire and aerodynamic improvements.
 

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Re: destroking the T5 (POWERSTROKE)

Also consider that if you went to a longer crank, kept the same conrod, you may run into interference with the edges of the block and the conrods. <p>If you went to shorter conrods, you would actually be gaining displacement. <p>Keep in mind that with the R's engine some of the more adventerous have discovered that with our stock K24 turbo the top end seems to be about 375 HP. To get above that requires a whole lotta rebuilding. Estimates run about $15k to $20k. <p>
 

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Re: destroking the T5 (needsdecaf)

dont need to rebuild engine to break the 375hp mark.. but will need FMIC, turbo etc.
 
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