So I have a 2005 Silverado 1500 that has 223K on it. I've taken my sad complete base model truck and turned it into something semi decent by adding factory cruise and factory fog lamps kit to it (honestly for safety and fuel consumption reasons). I also replaced the broken factory radio (RIP the sonofab*tch ate my Deftone's CD) and proceeded to keep it after being repeatedly punching in the giblets...

I'm an (angry) engine guy by trade. I used to produce some pretty wild Quad 4 engines in the late 90's and early 2K's, so I decided to look into what options I had with my 5.3L Flex Fuel engine. I noticed that the 6.0L drops directly in and will work with a ECU re-program. That's all well and good, but I want something a little bigger. Something that I can drive daily, NOT race, but if I want to merge in traffic and I give it gas, it opens up and goes. I found both a 408 and 413 cu/in stroker kit. The 413 kit had 6.125" length rods and a 4.100" stroke, it's on Ebay right now for 2K. The other kit I looked at the GM High Performance Tech article and managed to track down the parts they used and pricing.

The questions I have are:

What kind of fuel consumption can I reasonably expect going from a 5.3L to a 6.0L? I don't ever romp on my truck now, I stay between 55 and 60 at all times, but I know that (and you Yinser's know) that driving on the parkway, sometimes you need some extra oomph. What consumption can I expect in going from a 6.0 to the stroker?

Do I have to modify the block and clearance the walls of the block for connecting rod clearance with the stroker?

I've asked around and have heard not to build out the stroker unless I am going to race it. Then again, I've read people are disappointed with the power of the 6.0L when they do the swap. I figure If I'm going to do this, I'm all in, including the 4L80E transmission swap. I know some of you have done this and I am looking to get as much information as I can before I take the plunge and start doing this again. I mean if I can build 2.6L Quad 4's, this is just.... 4 more cylinders right?(greatly under-exaggerated)

Thank you in advance for any pointers, information, caveats, and pitfalls to watch out for, all information is greatly appreciated.

- Josh

 

More displacement means more torque of course (who doesn't want more power). Your 2005 truck has a gen III engine, so make sure the replacement short block is a gen III too (makes the swap easier). If the choice is a stroker with a 4" crank (408) vs. a 4.100" or 4.125" crank, definitely stay with the 4" crank. The longer stroke pulls the piston too far out of the bore at the bottom and the crown of the pistons are thinner/weaker due to the wrist pin location moving the ring pack up farther to the top of the piston. The real long stroke cranks have a greater chance of oil consumption. That said, I would caution you about buying performance parts on eBay. I'd get a complete forged stroker 408 from either Texas Speed or Thompson Motorsport. Yes, the block has to be clearanced for a longer stroke crank. Short blocks from either of the two places I already mentioned will already have this done.

 

Based on your post, a bolt on 6.0 will do fine.

Look for a 05 or newer gen lq4 or any year lq9. The lq9 has a half point higher static compression than a lq4.

There's a dyno sheet on this board with a full bolt on, stock cam 6.0 putting down 350hp to the wheels.

 

Give us a call when you have some time to discuss your needs. I have a pretty good idea what you are looking for based on the info above but we can save you $ and time by putting together the correct combination of parts. Let us know how we can help you get the motor you need.
Thank you,
Kyle
Thompson Motorsports
972-853-0518