blue89irocz

I am new to the site and am researching the LQ motors. My question is, is there a difference in the later to newer models? I am looking at doing a single turbo build for a street/strip car.

A.R. Shale Targa

iTrader: (2)

Some say that GM improved the rod bolts in the 00-01 era and IIRC the 03
engines have the teflon coating on the piston skirts for quiet startup and
less friction

badazz81z28

iTrader: (6)

I was under the impression the only difference was the later ones had aluminum vs cast iron heads...

JWAbercrombie

Early lq4 has cast heads and the crank is longer in rear, head bolts are different length compared to newer motor and they have press in wrist pins. And I been told older lq4 has different reluctor wheel. Not 100% on last part though...
People have put aluminum heads on them and made good numbers but from what I've been told your better off to find an aluminum motor just due to it being more up to date with the ls1 type set ups

radchevy

iTrader: (4)

the 2000 and older LQ4s have a longer crank shaft. no one make a after market flywheel. I have been there had to change out the crank to put a sfi flywheel on it.

blue89irocz

Alright thanks folks

RezinTexas

sometime in '04 the changed the length of head bolts, and got the "LS2 style" rods with press-fit pins. That's also around the time that flex fuel and DBW started.

1FastBrick

iTrader: (16)

99-00 had cast Iron Heads and a special longer Crank shaft that will only work with the 4L80E.

Starting in 01 they used the standard crank with a spacer between the flexplate. They also went to the 317 aluminum heads with MLS gaskets.

01-late 03 had 3 different size head bolts lengths and pressed pin LS1 style rods

04-07 had 2 different size head bolt lengths and should have the LS2 style rods with Floating pins.

Not sure exactly when but GM introduced the garfel coating to the sides of the piston to reduce the piston slap around 03.

As far as the throttle body goes it depends on the application. They had cable actuated TB's on the Vans all the way up through 2006.

RezinTexas

my '04 LM7 had LS2-style rods and press fit wrist pins. I would imagine that some 6.0's got this as well.

1FastBrick

iTrader: (16)

I have never seen an LS2 rod with a press pin.

I have seen some early 04 units get LS1 rods with Press pin's. That applies to every engine in the LS family.

The LQ9 had the floating pin introduced in late 2003 as the second design.

For example If you look up LS1 Pistons for a 2004 corvette in the GM parts system there was a design change in 2004 were they went to the Floating pins.

RezinTexas

my '04 LM7 did, here is how I disassembled them

1FastBrick

iTrader: (16)

Do you have a pic of the small end after the piston was removed???

RezinTexas

here is a pic I found in my file.

blue89irocz

Thanks guys great info.