JF74chevelle

Hey guys recently picked up an LQ9. It spun number 2 rod bearing and obviously it needs a new crank and rod.

original plan was to swap the 6.0 in place of the 5.3 in my 2001 Silverado. It’s a z71 4x4 with a 4l60e and 3.73s on 34s. I’m aware the 60e would live a short life behind either engine so I’ll address that separately.

the bores on the lq9 are actually flawless the cross hatching is still visible and this is actually one of the cleanest engines I’ve ever torn down and inspected. So I’m thinking I’ll lightly hone the cylinders since I already have a single ball.

Since it’s a truck should I go for the extra cubes? I will be towing a boat every once in awhile. It’s a daily driver but I take it on road trips, camping, tow and adventure out into the desert and woods, and snow.

Corona

Ls1tech


Non Common Sense...


Budget?

Hp is Tq ....

G Atsma

I would inspect the crank first. It might be salvageable.

01CamaroSSTx

iTrader: (3)

Crank could possibly be machined for re-use but going with a stroke crank with the rods and pistons to boot is gonna make more power and torque. PERIOD

Decisions...Decisions!

Corona

Eagle Don't Cost ......nothing how does U want the Stroke?


Center Counter Weight is for a Person with the Need of 8k +


Stroke Before anything Top End.... Cam, heads, etc.....

6.0/6.2 reference...= 402 to 418 easy....


Kills anything below it with Cubic inches without the Help from the Punk / Pump of Forced Induction....
​​​​​​

383z

iTrader: (2)

For what you want to do with your truck....I would not stroke the engine unless you want overkill and have money to blow. I would keep stock size, BUT I would go with custom cam, truck l92 rectangle port intake, LS3 heads, long tubes, good exhaust, and tune. That should be a little over 400rwhp compared to the 230-240hp you were at. A custom cam will put Powe where you need it to tow and to start moving. Not at 6000 rpm's.

01CamaroSSTx

iTrader: (3)

Nothing more than an air pump.

How big of one you build or how much air it can move depends entirely on you. You can do to one without doing to the other but your just defeating the purpose.

Corona

I like this Guy....

Basic Wins Fights ...

Corona

Who Ever Looks for 2nd Place among Friends



Isn't a friend....

​​​​​​
Alpha Male.....

84ta406

iTrader: (6)

If you have the budget, definitely more cubes. Rebuilding my blown up LS2 would have cost the same except for the added cost of the crank for another $800, so I had a Callies Compstar crank put in.

Corona

Rpm that Doesn't Make $ is a Waste of time....

Rpm does Equal to a faster ET but if,

no $

Reliability is Momma.

Everybody Loves Momma...

Like guys Need to Watch Yellow Stone... & Kevin Costner

Simple on Simple and good Drinking & Watching to make you Think... I need my New Season!


My Fault. Watching Yellowstone.


Keep it Simple with Common Sense..

JF74chevelle

I should’ve mention that the crank is totally wrecked, ground down a lot.

G Atsma

Save your $$. Get a stock crank and build your lower end. Stock LS lower ends are unbelievably strong. If towing is your goal, it already has 10:1 compression, add a good low-to-midrange truck cam. If you can get a 4L80E/transfer case out of a wrecked HD truck you will be way ahead .

Corona

Budget is King 👑


$50 to $100 to $150 dollar Used Factory crank... all depends on Who's Selling....75 sound like me and what I'd pay.



$600 - 750 dollar 4.0 crank ....I paid $700 no Tax
As cast non Forged cost even Less...


Both Use 6.125 rods.... H beams $550 I paid...


Piston are a Wash .....they sell Either at Bottom rate cost ....


Either would Like to be Balanced... $150+

When back In Houston ....$150+ goes to 👆 Covering ....duh Balancing....

Corona

If ones about that life .....saving a few Coins to make the budget isn't about 💩....


But if you've got a tight Budget .... common sense...
Hell just buy a Used 6.0...the one I sold is Still being used...

Elijah got that from me for $400 the Entire engine. I took his Rod Bearing Knocking engine And Scrapped everything....Spare Block.

Summitracing

Is $699 a lot to pay for the extra 50+ ft./lbs. under the pedal at every rpm at all times for the life of the engine?

The following 2020 Hot Rod Magazine article was a little strange, but interesting at the same time. It started off as a test of "stage 3" cams on a stock LS3. After a baseline, they plugged in our Pro LS SUM-8710 230/242 113 + 3 .625/.605 cam. Next up they wanted to try SUM-8705 (identical to Chevrolet Performance Stage 3 234/277 .595/.595 lift 107 LSA cam). Look at the exhaust duration and LSA and it's little wonder that the flycutting required to run that would have made the LS3 piston a time-bomb. So instead, we did what anyone with an unlimited parts budget would do and threw a Pro LS forged stroker rotating assembly at the problem. Easy peasy. Problem solved. We jest, but it's all in the name of science. This back to back test gave us some very good data on what one could expect to happen with common 4" stroker cranks and the power curve.

Here's the Hot Rod article

JF74chevelle

if I want to use that crank, could I use my current gen 4 rods and get pistons to accommodate the stroker crank and still use the gen 4 rods?


thinking I’ll run the above crank, and these pistons

https://www.summitracing.com/parts/dms-k1931-4000

that’ll allow me to use my current gen 4 rods

Summitracing

Yes, those have the correct pin diameter and compression height to run your rods. That's a good value for sure!

JF74chevelle

my buddy has a set of 241 heads he’s pretty much give to me, running those unported, with a stock truck intake, what cam would you recommend? This’ll be a daily and occasionally towing. Road trips etc.

Corona

Easy attention get"er with a quote for a World wide question...

Summit Racing, do You Guy's offer the or a
Center Counter Weight Crank? If so is it at Fair market place cost? Maybe a good idea if not into production...

😉