Stroker Kit on KA-T?

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kimpton9889
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I was lookin at doing a stroker kit on my KA but i want a turbo also. Has anyone tried this. if so how good is it?


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Razi
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superDorifto
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Also the KA is already stroked (sorta)...adding a longer stroke is only gonna be worth for the top 1% of builds where every other power adding option has been exhausted.

is like putting a jet engine on the Wright Bro's first plane...lots of other places to improve before we jump to that step.

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neverlift
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only good thing in that kit is the fully balanced crank, a few attempts were made at getting just fully balanced cranks made, as far as I know they failed. Leaving the stroker kit the only option with a fully balanced crank. next best option is blue print the motor with the goodies like superdori here, I;d get the crank balanced then have the assembly balanced.

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superDorifto
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neverlift wrote:only good thing in that kit is the fully balanced crank, a few attempts were made at getting just fully balanced cranks made, as far as I know they failed. Leaving the stroker kit the only option with a fully balanced crank. next best option is blue print the motor with the goodies like superdori here, I;d get the crank balanced then have the assembly balanced.

Its not in the catalog, but if you call BC they will make you a fully balanced standard stroke crank...for about $1000 bucks.

Again, the only motors that will be able to use something like that are the builds that are already on the hairy edge of what the KA can do. Normal stroke with fully forged internals, the right fuel set up and a proper turbo system and they can already hit 700 + HP...not much use for the for the balanced unit unless someone wants to overbuild.

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asoomal
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Not really HP goals, more about high RPM reliability. I'd love to have a 350WHP KA-T or KA-R with a fully balanced crank.

8000 RPM shifts :O

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superDorifto
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asoomal wrote:Not really HP goals, more about high RPM reliability. I'd love to have a 350WHP KA-T or KA-R with a fully balanced crank.

8000 RPM shifts :O

But again....is $1000 plus machining costs worth an extra 1000rpm?... you can buy a bigger turbo for that amount of money, or stand alone fuel management, or any number of other mods and see the same tq/hp result. I stand by my original statement.

This is only beneficial to people in the upper reaches of KA Power output.

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asoomal
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It'll be far more reliable past 5000 RPM's, it's not about the HP gains (I'm talking about the FCW crank for the stock stroke). It's about making the engine be able to reliably spin much smoother at the upper end. Plus a bigger turbo will move the powerband higher....so the power band stays the same pretty much (ex. let's say max torque is achieved at 3500 RPM's and stays flat till 5500 RPM's, HP starts to curve from 4500 RPM till 8000 RPM. With a bigger turbo, the torque curve might start at 4000?4500? RPM's and still won't be able to rev as high, reliably.) Obviously performing head work would have a much more effect on the power band, but the FCW crankshaft will allow the motor to run in harmony.

$1000 isn't too bad for a FCW :S

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neverlift
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hell yes a grand is worth it, Look at it this way, at 5500rpm the stock crank is trying to tear itself to pieces(dynos almost show it) so in reality you would be gaining like 2500rpms worth of usable revs. Thats a gain even on the lowest level of building IMHO. On a stock ka with minor upgrades a fcwc would make gains simply due to being able to rev higher. I will say there will be a point of diminishing returns due to piston speeds at such rpm. If the gt and scca guys can make power at 11~12k a stockish ka would like to rev out to 7500 no problem..

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Razi
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superDorifto wrote:
Its not in the catalog, but if you call BC they will make you a fully balanced standard stroke crank...for about $1000 bucks.
Whoa, whoa.
I did not know this.

I'm definitely contacting BC whenever I'm rebuilding my KA.

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asoomal
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neverlift
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razi updates on the stock stroke crank lol, make sure its not just a mod'd stocker, I can get my crank balanced.. bu a true fcwc is ideal imho

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Razi
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Okay!

Btw, there's a thread on KA-T.org about using a FCW crank from another car to work in the KA, except he also wants to destroke it to 2.2 liter I think.
It hasn't gotten anywhere though.

http://www.ka-t.org/forums/viewtopic.php?t=52121

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neverlift
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yeah I heard about the l20 crank setup, but I want to keep my 2.4 liters.

wonder how the destroked(2.2) would hold against an stroked sr????

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Razi
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Just got an e-mail from BC.
$1960 per crank. :( Not $1k.

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asoomal
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I smell a group buy.

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neverlift
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negative.
2 grand, so the pistons are just oem and rods are what cheapest they can get? isnt the whole kit only like 2300 bux?

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superDorifto
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The pricing difference is most likely its because the build the cranks in lots, like any good manufacturing company. It makes the parts cheaper if you get a machine shop to make you 10 sets of cranks and rods at once rather than 10 separate cranks that are all bought seperately. Every non stroker crank is essentially a one off...meaning no discounts.

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Razi
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The stroker kit is 3194 with Sportman rods and custom pistons.

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D-UNIT
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A fcw crank would be heavier according to my engine building friend. That means slower revs. He says a very good balance on a hcw KA crank should easily spin to 8500 rpm smoothly. He points out that the 72mm stroke 2TC engines are spun to 10000+ rpm w/ a hcw crank. In my case its true but i only spin to 7600rpm with no vibrations at all! Butter smooth all the way to the rev limit. Its all about race balance and hardware...
Last edited by D-UNIT on Sat Aug 27, 2011 1:14 am, edited 1 time in total.

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asoomal
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Eh, I'm pretty sure most of us will go with a lightweight flywheel anyways.

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neverlift
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you might rev that high but its not good for the engine, the ka gets very violent after 5500rpms.


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