I asked a few times in another thread regarding boost and LS1's but figured Id actually start my own thread regarding my questions. Here's what I know so far about boosting an LS1.

Basically the rod bolts have to go-CHECK

Pistons need replacing because they are the weak link&I wanna be safe-CHECK

Rods seem to be forged from what I read but are good for xxx rwhp??

In order for me to run 500 or so rwhp on an otherwise stock LS1( stock cam, stock heads) would changing the above on the motor allow me to run my goal safely?

Now for the fueling system, what else am I going to need? Larger injectors (60#?) And a fuel pump?

Any information in this category is much appreciated, Id really like to learn all of the things I need to make sure the motor is built like a brick **** house and wont break

 

many people are running those kind of numbers with stock pistons and rods.

 

You'll be fine stock up to 600rwhp.. i would do arp rod bolts, 6.0 heads, springs, ls6 intake.. 60-65 injectors- def bigger fuel pump

good to go.

if you want to be safe- forge the whole motor- rods are not forged- crank is good for alot of hp 1000hp or more

 

I just wanna run 500rwhp safely. If I can hit that number safely, im a happy man. The aftermarket is huge for these motors so I dont know everything thats out there. The 6.0L heads are used to lower compression ratio im assuming? And what vehicle do they come from?

 

6.0 317 heads are used quite frequently to lower compression. I would not bothter going into the motor until you are ready to do it all up. You can run around those power levels as said on bone stock engine. Well nearly some 918 comp springs are ok idea to ensure no valve float under boost.
You can run on stock compression with stock heads just run lower boost or timing.
With those 6.0 heads you could run a couple more pounds of boost depending on which turbo you get. Bigger turbo makes more power than smaller turbo at lower boost .
You need a spot on tune on the stock pistons. You need to not get greedy on timing or afr but timing is key. Staying conservative there as the stock pistons are fragile and unforgiving of tuning mistakes.

For sure I would have some incar scanning tool to keep an eye on knock at all times.
As said a inexpensive intank pump like racetronix one and 60 pounders is all you need for fuel system upgrades.Stock lines ,rails ,etc are ok at those power levels.

 

are we talking 5.3's with 6.0 heads?

 

Now that worries me a lil about the pistons, because i've read that before too. Since id be doing the rod bolts, might as well change them out too tho.

If I choose to go with the 6.0L heads, would the overall lowering of the compression be more forgiving on the pistons? BTW what can you expect these heads to lower the CR to?

 

You will be fine engine wise at 500 rwhp. Everything else will suffer though.

 

I'm on stock internals with 556rwhp, haven't been for long but everything except the rear end is fine so far

 

For that hp range I would upgrade the rod bolts. Those are the weakest link in the rotating assembly.

 

If you're going to start tearing into the rotating assembly then do the whole thing right.

Get a good tuner and you'll be fine with the pistons.. 533rwhp and its still rolling around.. almost 2 years

 

A local guy is making 700rwhp on a stock LS6, bracket races his car, just a ton of runs, as a matter of fact he plans on going out both days this weekend for some bracket racing.

 

I think its a bit cheap and not that smart to go all the way into the engine and not change out pistons, rods and rod bolts. Cranks are strong factory so unless you want to go big power or biggger stroke then stock crank is one area you can cheap on.

I am not sure how strong the factory rods are but might as well change them out if you go in and be ready then for much higher power levels.

I have seen personally many stock piston failures in buddies cars. one in procharged car and one in sts turbo car. Have piston in my garage keep as souvenir.
I have not seen many rod bolt failures. I think the pistons are much more fragile than the rod bolts.

But again I say just drive the car with stock bottom, maybe some 918 springs. Put on 317s to take compression down by think half a point or so. Be conservative on timing and boost and stock engine should live until you are ready to do the motor up properly.
You will have to spend money on other areas like for sure trans if its 4l60 and for sure clutch if its m6. Rear end depends on traction which you won't have much on normal tires at 500 up rwhp. Try to run drag tires and yeah you m6 guys will for sure need a new rearend autos guys can run the stock rear longer.

Fuel and tuning is reasonably cheap as said upgraded pump is like couple hundred bucks and 400 or so for 60 pounders .Good idea to get flow matched for FI applications.
Hptuners works good on FI cars and is semi user friendly if you know a bit about tuning .
Some upgraded valve springs are cheap insurance against valve float under boost.

Remember the words cheap and FI don't go very well together. It can usually take double or more what you think it will. So if you don't have pretty deep pockets might be best to stay with NA or nitrous.

 

Cheap, fast, reliable......pick two

 

I have been running 7psi of boost on my stock LS1 for over 16k miles since Fall 2007 now (508rwhp / 513rwtq). I upgraded pushrods to TSP hardened ones. Upgraded valvesprings to LS6 springs. Upgraded fuel pump to Racetronix in-tank with hotwire kit. And fuel injectors to 60# injectors. I have a safe streetable tune and have not had any issues. I DD the car in the warmer weather, take it on roadtrips to NY to visit family, taken it to a few track rentals with my carclub. Still on stock trans and 10bolt (but only on street tires. No stickier tires until the rearend gets upgraded). And I have the LS7 clutch.

Eventually I will upgrade the trans, rearend, and rebuild the motor. But until something gives out, I plan to keep driving it.

 

Im on stock internals for now, but that will soon change I have found the limit of my single Walbro pump however. My tune is set up safe, and I have been driving the car with the power level in my sig for almost 2 years now. I believe that the reliability is found in your tune, and a little luck w/ a stock rotating assembly.


Troy

 

My car calculates to about 640whp and has a stock junk yard 5.3 shortblock in it w/ 6.0 heads. Stock rod bolts and the cheap felpro head gaskets with a light coat of spray paint on them. 3 years and beat to hell not a single issue.
500-550whp I wouldnt worry about anything.

 

I think you would need to replace the rear and the clutch first. should be fine on the engine.

 

Just don't spin the motor too high and you don't have to worry about the rod bolts being the limiting factor.

 

I think thats the exception not the rule. 7k on my motor since I did the mods in my sig and I broke a ring land car is down for the count and I'm saving for a 402 short block