How long did your "Long/Short Block 4.8 5.3 5.7 6.0 6.2" last Boosted?
04-04-2013, 11:08 AM
#1
TECH Fanatic
Thread Starter
iTrader: (16)
Join Date: Dec 2005
Location: Alvarado, Texas
Posts: 1,299
Likes: 0
Received 0 Likes
on
0 Posts
How long did your "Long/Short Block 4.8 5.3 5.7 6.0 6.2" last Boosted? I see alot of threads about boosted LSx engines making tons of power and am curious to how many of you guys have blown one up from either user error, tuning errors or strait up power.
So far I have had pretty good success with these little monsters, but have also had a failure aswell.
Lost the last 5.3 in my blazer about a month ago, had #5 injector go bad which melted the piston on relatively low boost and timing. AFR was 10.97, 9psi, 11 deg timing, midway thru 3rd gear I melted that slug. Actually didn't know anything was wrong until I pulled back into garage and noticed puffing smoke from my breather. ZERO compression on #5.
Since then, installed a L33 long block, new 60lb injectors and been flogging ever since with no issues on 5-9-13-15psi.
Would like to see actual experiences that killed it.
What LSx it was? Boost? Timing? AFR? When during pull?
So far I have had pretty good success with these little monsters, but have also had a failure aswell.
Lost the last 5.3 in my blazer about a month ago, had #5 injector go bad which melted the piston on relatively low boost and timing. AFR was 10.97, 9psi, 11 deg timing, midway thru 3rd gear I melted that slug. Actually didn't know anything was wrong until I pulled back into garage and noticed puffing smoke from my breather. ZERO compression on #5.
Since then, installed a L33 long block, new 60lb injectors and been flogging ever since with no issues on 5-9-13-15psi.
Would like to see actual experiences that killed it.
What LSx it was? Boost? Timing? AFR? When during pull?
Last edited by Vcious04; 04-04-2013 at 11:14 AM.
04-04-2013, 12:34 PM
#7
Staging Lane
Join Date: Mar 2013
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
4.8 liter hellfire rings gapped for boost. Main & Rod clevite race bearings. ARP rod bolts.
744 rwhp @ 18lbs of boost and 11,200 miles and counting. And I beat on this thing like a red head step child.
The 4.8 liter is where it's at!!
744 rwhp @ 18lbs of boost and 11,200 miles and counting. And I beat on this thing like a red head step child.
The 4.8 liter is where it's at!!
Trending Topics
04-05-2013, 01:16 AM
#8
12 Second Club
iTrader: (2)
Join Date: Apr 2009
Location: PNW
Posts: 900
Likes: 0
Received 0 Likes
on
0 Posts
I ran my lq4 for about two year with about 10000 miles,ran probly 300lbs of nitrous threw it on a mail order tune.then went turbo last spring and ran it on #14 till august when I shattered a piston and cracked a cylinder wall because I got greedy and wasnt paying attention to my gains at the track while tuning
04-05-2013, 07:46 AM
#11
On The Tree
Join Date: Oct 2007
Location: Grapevine,TX
Posts: 121
Likes: 0
Received 0 Likes
on
0 Posts
My last engine did the EXACT same thing on number 5 !
I thought it was a combination of things , average tune, 15 psi , tight ring gap.
What was wrong with your injector? leaking, not firing ?
Looks like I need to look for other problems.
Mine was on E85
I thought it was a combination of things , average tune, 15 psi , tight ring gap.
What was wrong with your injector? leaking, not firing ?
Looks like I need to look for other problems.
Mine was on E85
04-05-2013, 07:54 AM
#12
02 5.3 king bearing, regapped stock rings, e85, 19psi, 19degs,
so far about 1000 miles.
Going sunday to see what it puts down on a mustang dyno,
was testing last night and seen 14.0 afr at 16psi/5800, ooopppsss. (I LOVE E85, SO MUCH FORGIVENESS) WHEN THAT HAPPENS
Still running strong and the plugs look good, (tr6 .028)
lil bastered runs
so far about 1000 miles.
Going sunday to see what it puts down on a mustang dyno,
was testing last night and seen 14.0 afr at 16psi/5800, ooopppsss. (I LOVE E85, SO MUCH FORGIVENESS) WHEN THAT HAPPENS
Still running strong and the plugs look good, (tr6 .028)
lil bastered runs
04-05-2013, 08:05 AM
#14
TECH Fanatic
Thread Starter
iTrader: (16)
Join Date: Dec 2005
Location: Alvarado, Texas
Posts: 1,299
Likes: 0
Received 0 Likes
on
0 Posts
Well honestly I knew #5 was a problem since I built this thing. I ignored it for whatever reasons. I changed plugs about 3 times going from Tr6's to TR7's and then to BRFE7's, everytime #5 looked hardly fired. no discoloration at all, very little sootiness when all other plugs were pig rich and sooty. My fault, no biggie lol. Live and learn.
04-05-2013, 08:30 AM
#15
TECH Fanatic
Thread Starter
iTrader: (16)
Join Date: Dec 2005
Location: Alvarado, Texas
Posts: 1,299
Likes: 0
Received 0 Likes
on
0 Posts
Now it's got an aluminum L33 5.3 that set me back $450 which is now lighter and more powerfull. Been throwing 5-10-15psi on it so far without a hitch. Pulled the plugs, all are even and burning great. However I will limit the boost to 10psi until I throw the meth on just for safety.
04-05-2013, 09:07 AM
#16
This would be bonkers in a 4x4 Toyota pickup.
04-05-2013, 09:45 AM
#17
I know it is not an ls motor but I figured I would share a sucess story of a 4 banger with cast pistons and oem rods. 4 banger making 400/400 for the last 50k miles on stock 8.5:1 compression cast pistons and 20 psi of boost on straight 93 octane with 14* of timing at peak rpm (6800) and 10* at peak torque. Car now has 210,000 miles on it with the same long block.
04-05-2013, 10:52 AM
#18
Staging Lane
Join Date: Mar 2013
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
Here is the cook book details.
2003 LM4 aka 4.8 vortec. $540.00 with harness and all sensors etc. Craigslist.
Clevite main and rod race bearings .001 off ebay $95.00
ARP 8740 rod bolts $70.00 off of ebay.
Hellfire rings $90.00
Those Chinese head studs $69.00 lubed threads in axle grease installed and lube nuts in axle grease and torqued them down.
I reused used the ML head gaskets they looked fine.
Didnt have the money for a cnc port job. So I spent $170.00 on a sweet *** 3 angle valve job. And had the valves back cutt.
OEM ZR1 Cam 211/230 .558/.552 122.5 LSA. From another forum member $70.00
Lunati dual valve spring kit with steel retainers used from another member $110.00
2008 z06 lifters used scored those off a dude on the camaro5 forum $48.00
Used comp magum pushrods $32.00
On3 turbo 76mm $360.00
on3 fuel injectors (they are suppose to be Siemens 60's) but they are chinese but in all defense they do work fine. So I scored a set of those used from on3 because a guy returned them. So I paid $100.00
Dual Bosch 044 O.E Replacement Electric Fuel Pumps $125.00 for both off ebay. (WARNING THESE FUEL PUMPS ARE LOUD) just make sure you put one on a boost pressure switch. Running both the pumps full time will drive you insane. So to make these work your going to need a "Speedflow connection fitting (part number 612-06) and your going to need a -6an to 3/8th adapter fitting. Put these pumps in the tank. It quiets them down a lot. These are far superior than those damn walboro pumps.
I mixed my own gasoline. Okay so I blend 15 gallons of 93petro with 5 gallons of E85. I call it "E42.5" and it works just fine for what I'm done so far. $58.00 per batch
I absolutely beat the hell out of this engine. It smiles and ask for more. I spin this engine 7000RPM and 18lbsof boost.
If you don't know by now I'm cheap very very cheap.
I spent around $1800.00 total and I can sleep at night knowing tomorrow it won't blow up.
I built it with my own hands my valve train is solid as it can be and the bottom end is basically refreshed and new.
If I can do it anyone can do it. $1800.00 for 744rwhp where else can you buy for that cheap?
I'm sure I could upgrade to a larger turbo and larger injectors and buy those wiseco junk yard 4.8/5.3 pistons. But I haven't found them used yet!
I'm not buying anything new if don't have too. Your trash & hand me downs parts is alright with me. I will be patient until someone breaks their engine and I will purchase their parts for the LOW! 
.