5.3L LS.. 491 hp and 445 tq... woot!

[Steve1968LS2]

Steve will the lq9 flat pistons work as well? is the reason the 4.8 were listed is for budget build?

I'm not sure.. what bore size are they for? We used the 4.8 since they are the same bore size as the 5.3L .. that means no machine work is needed.

[Jimmy Sean]

any photos of those coil mount thingys?

Steve would these be them?

found here http://www.lateral-g.net/forums/show...t=22536&page=3

[Mark Antrim]

This makes me want to junk the gen 1 and build one of these engines. I did price the pistons at work for the 4.8 stock pistons and they are a little pricey. It would be different, but dont tell the wife.

[93Polo]

Steve will the lq9 flat pistons work as well? is the reason the 4.8 were listed is for budget build?

They will not as the lq9 is a 6.0ltr with 4" bore vs. a 3.78 bore for the 5.3.

A 4.8 shares the same bore as 5.3 but a smaller stroke.

Gen 3/4 5.3s, 5.7s, 6.0s, and 6.2s all have a 3.622" stroke, and the bore keeps growing from 3.78" to 3.9" to 4.0" to 4.06" respectively.

[93Polo]

I like the dyno results and have been researching a 5.3 truck block build as they can be found cheap. Very intersting build with the piston swap.

This makes me want to junk the gen 1 and build one of these engines. I did price the pistons at work for the 4.8 stock pistons and they are a little pricey. It would be different, but dont tell the wife.

Another option maybe to buy a 4.8 take out motor and find crank and rods from a stroker build. I am not sure what length the 5.3 rods are and if they are the same as the other motors that share the same stroke listed above. You can get the 3.622" stroke crank from several motors. Also be sure the reluctor is the same count as the PCM.

Another option for saving some money would be porting the early truck 4.8/5.3 heads. They flow really well when ported. I have a set of stg 2s from http://www.totalengineairflow.com/ on my ls1 that made 436rwhp/415rwtq running a Futral 228/230 112+4, LS6 intake and stock 78mm TB that had been polished up. You would give up some power compared to the TFS heads which are very nice but it would be a heck of a bang for the buck. The 1.5 with a stock exhaust valve actually flow better than the stg 2s.

The 4.8/5.3 heads were the casting most used before aftermarket castings came out. They flowed better when ported than the Ls1 heads and were cheaper than the 243 castings from the LS6. 243 (ls6/ls2) and 317 (lq4/lq9) flowed better were normally bigger budget.

Ls1tech has all the casting #s in their FAQs.

[93Polo]

Steve, What size primaries were used on the headers. I apologize if I missed it. Great tq for a little motor.

[Samckitt]

Steve will the lq9 flat pistons work as well? is the reason the 4.8 were listed is for budget build?

The LQ9 is a 4.0" bore, the 5.3 is a 3.78" bore.

[19,69camaro]

This may sound like a dumb question and I apologize if it is but if I was to go for a budget 4.8, 5.3 or 6.0 build what would be the best donor Im not looking for crazy numbers just a even 350/350 would be fine. Ohh and aluminum is a plus trying to loose some front end weight. Also would like to mate it with a t56 any ideas it would appreciate it.

[Samckitt]

If I was looking for an LS motor (which I may do here soon) I think I would look for an LQ9 or an LY6. According to the latest Chevy Hi Po magazine, the LQ9 can be found in 02-06 Escalades, 03-07 Silverado SS & Sierra. Rated at close to 350 hp & 380 lb-ft. LY6 can be found in 07+ 3/4 ton Silverado, Sierra, Suburban and Yukons. Rated at 352 hp & 382 lb-ft.

Then I probably wouldn't be able to leave well enough along & I would get a 4" stroke crank & drop in to make a 402 ci engine.

[93Polo]

If I was looking for an LS motor (which I may do here soon) I think I would look for an LQ9 or an LY6. According to the latest Chevy Hi Po magazine, the LQ9 can be found in 02-06 Escalades, 03-07 Silverado SS & Sierra. Rated at close to 350 hp & 380 lb-ft. LY6 can be found in 07+ 3/4 ton Silverado, Sierra, Suburban and Yukons. Rated at 352 hp & 382 lb-ft.

Then I probably wouldn't be able to leave well enough along & I would get a 4" stroke crank & drop in to make a 402 ci engine.

If you're building a 402 don't forget the LQ4. The LQ4 is just about the same motor as a LQ9 except for piston dish both were iron block 6.0s with 317 heads unless the LQ9 changed late in the run. You could always swap to smaller chamber heads later on if you wanted more compression on a stock shortblock build.

[pjku79]

This seems to have been dead for a few years. Are people still doing this on budget builds? What are the down sides?

I have a guy at work that has been trying to sell me an engine and he has a 4.8 and 2-5.3 engines in pieces right now. I could use the stock 5.3 with 4.8 pistons, ls6 cam, and yellow springs.

Should be able to get the whole thing for $650. Keep in mind he tears down to inspect then rebuilds if everything looks good.

[hifi875]

I have a 5.3 w milled z06 heads custom cam 218/222. 595/598 lift. In my camaro. Runs good.

[DroptopJ]

Those are some awesome numbers for a 5.3L

[austindub]

Great numbers for a 5.3, but I have to ask the question... why a 5.3? Unless you just had an aluminum 5.3 laying around why not start with an iron 6.0 if you are going to go with aftermarket heads, change the intake, accessory drive, etc.? Either way, that motor looks pretty sharp and makes awesome power!

[trex1270]

I took a 5.3, punched to 5.7 using a torquer V2 on 112, carbed with PRC heads with a holley 750 ultra double pumper, put 420 to the tires with a manual...I figures 526 at the crank..oh yeah 10.8 compression.

[pjku79]

Because 5.3 are about $500 cheaper (iron to iron at least)

[pjku79]

This seems to have been dead for a few years. Are people still doing this on budget builds? What are the down sides?

I have a guy at work that has been trying to sell me an engine and he has a 4.8 and 2-5.3 engines in pieces right now. I could use the stock 5.3 with 4.8 pistons, ls6 cam, and yellow springs.

Should be able to get the whole thing for $650. Keep in mind he tears down to inspect then rebuilds if everything looks good.

Any comments to my message above?