thinking to go for more stroke, If changed crankshaft,what size of LS2 you will get?

[Abdulla]

Hi,

some one told me what to do with LS2 block ..... he said to get modified pistons and rods , with out changing the size of bore .... only go for more stroke by changing the crack shaft.

I want to kniow what size its will be ???? I don't know what size of stroke I should go for it without changine the bore ...... but can we say the size of the engine will be 402 c.i. or 408 c.i. or what ???

and what do you think about this idea ????

its like if I get 346 c.i. and just go for more stroke without changing the bore .... I will get 383 c.i. , he is the same Idea with LS2 wich has more bore , so I will get more than 400 c.i. , but what is the exact size ???? and how is thuis idea ??? will I expect huge power ????? I am afraid because I didn't see anyone do it until now .....

any help ????

thanks

[Stone4779]

The stock LS2 bore is 4.0" and the stock stroke is 3.622..

There are 4.0" and 4.125" stroke cranks available from the aftermarket...here breakdown of whats out there...

4.0" Bore x 3.622 stroke = 370 ci (stock setup)

4.0" Bore x 4.0" stroke = 402 ci (408 if bored 0.030" over, 415 if bored 0.060" over)

4.0" Bore x 4.125" stroke = 415 ci (420 if bored 0.030" over, 427 if bored 0.060" over)

IMO the shortest stroke possible while still mantaining the same ci is the best way to go...

I would say the best overall would be the 4.0" x 4.0" setup...its perfectly square rod/stroke ratio....a good mix of torque/hp...excellent for the street IMO. 402-408 ci should be enough for most people, unless you really need that extra power or you just HAVE to have the "427" bragging rights.

I am researching and waiting to see how low the prices on the LS2 stuff goes...then I hope to run that setup( 4.0 x 4.0 ) unless later GM brings out the 6.3/6.4L with a 4.1" bore with the same 3.622" stroke...they can either do that or just put in a slightly larger stroke crank (around 3.8") but Im hoping for the bigger bore(highly doubtful though)

Any one of these combinations is going to net you some huge gains....just swapping in a stock LS2 would give you some gains but if you going to go through all that trouble then why not throw in a longer stroke crank while its out? Unless money is an issue, its a very good idea.

Hope that helps..

-Chris

[Abdulla]

Thank you very much

you were helpful I appreciate your time

yes thats what I am thinking of ..... 4" bore and 4" stroke , without tuching the block at all :)

thanks and good luck

[Stone4779]

No problem.....:usa:

Also I'd like to note that the 6.4L in the concept GTO has a bore of 4.135"!

Halleluja!(sp?)

That means with that block (if it ever went into production) and a 4" stroke crank you would get about 430ci...and 443ci with a 4.125" stroke! No sleeving or anything...Heck, with a 4.125" stroke crank and a 0.30 over bore you'd be 5ci short of 454ci! I think Chevy might bring it back(Again, IF this block ever makes it into anything...) and just say its a 454...just like the LS1 is 346ci, not 350ci even though its still considered a 350...

Or you could just throw the 3.622" crank in there and bore it over 0.30" and have a true 396 ALL BORE motor!

That last one would be cool with a huge cam in it. Imagine a 4.135" bore 396 screaming at 7500 rpms.

later :)

[mikey]

Abdulla, we are building a 402 LS2 here now and should have some dyno numbers soon. The info is here:

http://www.rapidmotorsports.com/model_cats.cfm?pgTask=product_detail&intCatId=2&intSubCatId=66&intProductId=978&intModelId=2&intYearId=3

Mikey

[C6VetteMan]

I plan to wait for the LS7 block to become available.

440 cubic inches will be the magic number with it's larger stock bore and available stroker crankshaft!

[89FormulaLS2]

A 402ci LS2 will be just right for me. :)

Can't wait until it's up and running!

[SLED28]

Here's some combo's AVAILABLE. let me know if you need anything...

http://www.gmperf.com/page7.html