Building my LQ4 engine in my Denali XL

[livingez_123]

You can make your 500hp goal with the truck intake and a nice polished TB. if you tow 5-9k lbs, you will want a cam that comes on before 1500. a loose converter and towing heavy don't mix. converter slip (until it locks) creates unnecessary heat.

ATK builds a 408 short block for about $3,700

 

[Ridculous]

Thanks for the responses and information guys!

I already have a Trucool 40k transmission cooler and have been discussing the shifting point / stall with my tuner so we will see if a new convertor is apart of a build transmission.

I think I'll upgrade to the Kooks headers (had them and a vortech SC on my Jeep SRT8 and liked them). At this point those my goal is NOT horsepower it is 500 lbs of torque down low....if I get that same in HP great. HP doesn't allow me to tow 7000lbs of travel trailer + the weight of the Denali XL + 2 kids + 3 adults and 2 - 100lbs dogs very well.

I did speak with Texas Speed, ERL and ATK about a built short and long block...at this time (still waiting on the local engine builder to clean my block) I plan on using my block and have it built locally vs. waiting 4-8 weeks for another shop to build it and ship it too me.

I think I'll chance my license plate to the griswolds!

 

[FreshLikeOprah]

Go to Performancetrucks.net... There is plenty of knowledge over there. Those guys have a PH.D in LS engines.

 

[Ridculous]

Yes sir that is where I have been starting my search

 

[Front Street]

Keep us posted!

My LS guy also likes parts from Texas Speed, he used them in a TBSS build almost a year ago and the guy loves his engine. I'd love to hear what you go with to get the Torque you need.

I too am going local for the build, which is always cool to help out our neighbors. Plus, I've learned that doing a cool out of the box build will get you into the network of hookups and discounts for all kinds of stuff! It's pretty exciting to be able to make connections to powder coat guys, dealer hookups and other areas.

Hope you find the same is true!

 

[M Hankel]

If you go FI you don't really need to stroke it to a 408 to get your hp/tq goals. It's just added cost for not much gain.

For a FI build, I'd do a 370, which is a stock crank, forged rods and forged pistons (.030" over bore). The stock crankshafts are nearly unbreakable up to around 900+hp. Put the money you saved from not needing a stroker crank toward a good roots style blower, preferably one with a built-in aftercooler. A roots or screw type blower will give you exactly what you want, which is a lot of torque down low and instant throttle response. With this style blower you won't even notice not having a stroker engine. If you go this route, make SURE your engine builder knows this will be a forced induction engine so he can gap your piston rings accordingly.

Pulling a heavy load on a long mountain pass with a steep grade will build a shit ton of heat so you'll need a way to keep (IAT's) intake air temps in check so you might look into a meth injection system.

Keep the stock 317 heads and drop in some good valve springs with at least 150lbs on the seat pressure. Those heads will work perfect for you hp goals with the forced induction.

Budget for some decent fuel system upgrades, pump/s, injectors etc.. That stuff can add up quick.

Run as big of a header as you can afford, size the exhaust accordingly. The 1-7/8" would be perfect IMO. A 3" y-pipe to a single 4" or dual 3" exhaust.

Research a good trans builder and talk to them about your goals. RPM transmissions is one of the best when it comes to these autos.

Good luck man.

Mike

 

[Ridculous]

Found out that if I go the supercharger route I can only run 91 or better.....going N/A so I can have the option of different fuels on this bus.


Callies Dragonslayer rotating assembly, arp head bolts, studs, blue printed block, ported stock heads, new lifters, valves, retainers, push rods and other goodies ordered plus a new comp cam

Will be ordering next week a set of high flow catted headers, injectors and possibly a new intake manifold (or stay stock intake or TBSS to retain more torque?)....then work on the transimisson

Stay tuned!!

 

[livingez_123]

If you go FI you don't really need to stroke it to a 408 to get your hp/tq goals. It's just added cost for not much gain.

Really? your nuts Hankel. The 408 in NA form will give him more torque than the 370. And if in the future he wants to do a mild turbo or blower build he will have 500+ftlb of torque when ever he needs it. the longer stroke of the 408 is what gives him the torque he wants, the 370 will be a disappointment because he will have to run a larger cam to get the ###'s he wants. the 408 will provide the ###'s he wants with a smaller cam. and if he goes turbo/blower he will allready have a good cam for it.

Remember the saying...theres no replacement for displacement. The 408 is a perfect motor for someone who intends to tow.

 

[M Hankel]

If you go FI you don't really need to stroke it to a 408 to get your hp/tq goals. It's just added cost for not much gain.

Really? your nuts Hankel. The 408 in NA form will give him more torque than the 370. And if in the future he wants to do a mild turbo or blower build he will have 500+ftlb of torque when ever he needs it. the longer stroke of the 408 is what gives him the torque he wants, the 370 will be a disappointment because he will have to run a larger cam to get the ###'s he wants. the 408 will provide the ###'s he wants with a smaller cam. and if he goes turbo/blower he will allready have a good cam for it.

Remember the saying...theres no replacement for displacement. The 408 is a perfect motor for someone who intends to tow.

You do realize I was saying if he decides to go with a blower like a magnacharger that going with a stroked crank is not needed. A blown 370 will make 450-500rwtq by 2500 RPM. Show me a naturally aspirated 408 that can even come within 60-80 of that number that low in the RPM range (towing range).

There is a replacement for displacement, it is forced induction or nitrous.

Mike

 

[Ridculous]

Been looking for a nice set of catted headers to keep the drone and noise down for the family any input on people with catted LT headers....looks like not too many options

OBX for $800-$900
AMERICAN RACING $1500-$1600
and maybe Kook's long tube headers are the only ones I have found. All LT headers are going back on the stock exhaust. Going cattless is not a option due to the noise. My wife had me remove some aftermarket exhaust on my old SRT8 jeep because of it. Your thoughts and recommendations are welcomed