sixt9er

iTrader: (2)

GM lists max stroke for iron LQ4/LQ9 blocks at 4.125". Is anyone using a 4.0+" stroke without issues? What are things to be aware of when using such a big stroke? What are your combinations and what type of hp are you getting from these set-ups? Thanks fellas...

Beau@SDPC

iTrader: (14)

SCHWANKE does it, but we do not recommend it. It makes for a VERY interesting piston design unless you use a different rod (shorter). Which would be difficult as well due to it needing a specific amount of length to at least clear the counterweights.

sixt9er

iTrader: (2)

Hmmm...thank you. There would probably be NO benefit to running such a stroke with a stock block then, huh?

Beau@SDPC

iTrader: (14)

People do it. I personally do not like such a long stroke on a smaller bore. you can build a 427 out of an LS3 block and get the bigger bore with less stroke of course. 4.065 x 4.100.

sabastian458

iTrader: (5)

much more expensive and harder to find used block tho.

sixt9er

iTrader: (2)

^^^ Yeah!

69_YENKO

iTrader: (16)

such a long stroke(4" is about max recomended) in a stock block pulls the piston too low putting the wrist pin centerline(i forget the exact term, guide point?) below the bottem of the sleeve causing lots of stress. broken pistons are a not uncommon occurance. but hey, its cheaper initaly right lol.

KCFormula

iTrader: (4)

Run a search. Plenty of us run a 4.125" stroke in a LQ4/9 block with out issues. Mine has seen 8500rpm fwiw.

1CAMWNDR

iTrader: (21)

4.100" or 4.125" cranks can be done with proper pistons designed to keep the rings from coming out the bottom of the bore.

tilly

iTrader: (5)

Beat me to it, you bastard

Beau@SDPC

iTrader: (14)

I am not saying it cannot be done or never has, but the design of the piston is the thing i worry about. I know they work and I know for the most part they are popular, but we do not choose to build them as a short block. I can get you the parts all day long, but we will not assemble them as a shortblock.

sixt9er

iTrader: (2)

Any oiling issues or "using oil"?

99T/AVert

iTrader: (5)

I would like to fire this up again since I am building a LQ9 425.

Components:

Calies Magnum XL 4.125 crank
Calies 6.125 rods
Wisco custom 4.050 piston
MS4/111 cam
WCCH l92 heads
LS3 intake

How far into the bore of the cylinder can I go or is .050 the safe max? Is there anything I should be cautious of or should relay to my builder, ie- any secret tricks

the_merv

iTrader: (88)

^^if you used a 4.000 Crank it would be a 415..check your numbers again..

Also, I would look for a different Cam if you plan on going with the L92 Top-end..get a custom Cam.

99T/AVert

iTrader: (5)

whoops! lol, thanks for the check, hit the 1 instead of the 2

What would you suggest? I already have the MS4 @ 111 lsa. I think its the best sounding cam that Ive heard, I LOVE the nasty chop lol, also all the great reviews is the reason I got it.

Again what your you suggest? I would want something that sounds like it is trying to hack up a small child after it just got done sucking it in through the intake lol.

the_merv

iTrader: (88)

Well it may sound like that with the L92's, but it won't perform it's potential. The L92/LS3 Heads are picky when it comes to a Cam. I have a 114+3 LSA Cam, and at a 800 RPM Idle it sounds pretty sick..

I had Patrick G spec mine..get with him and see if he can help you out.

sixt9er

iTrader: (2)

Pat G just did one for me...can't wait to hear it, but more importantly, see it perform...I'm running CNC ported L92's. Looking for at least 600 FWHP. Hope it can be done...decided NOT to run the 4.125" crank though...keeping it a 408 CID N/A engine.,

Schwanke Engines

iTrader: (1)

You should be able to hit the 600 flywheel mark pretty easy with ported heads. Just finished dynoing a 415 with stock heads running race gas we were at 595hp 565ft-lbs at the wheels, this is in a road race car though.

redsilv

doesnt the wiseco pistons compensate for the rings at the bottom of the stroke
ie;wiseco rotating assembly (wiseco website)
seems they may have the oil control and broke pistons in check

1CAMWNDR

iTrader: (21)

Yes, Wiseco is on the money with pistons for 4.1" and 4.125" cranks.