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How to upgrade the 5.3l v8.

Ghostbuster

Well-Known Member
Messages
861
Location
United States
Without getting a supercharger.
So like new:

Camshaft
Pistons
Rods
Valve springs
Lifters
Spark plugs
Intake
Exhaust
Headers

Stuff like that.
And of course a proper tune maybe PCMofNC or a dyno tune.

What kind of numbers do you think it could get. I was think at least 400 hp and 400 ft lbs of torque.

And I'd also like to upgrade the 4l60e while I'm at it.

I'd like to do all of this after I hit the 100k mark so I have some time to save some $ and learn about all of this. Any input/ information regarding upgrading is appreciated.
 

cgalpha08

"Like Nothing Else"
Messages
3,584
Location
Indianapolis, IN
I'd say north of 400 hp. A wild cam with headers and true dual exhaust (if you could even squeeze that in there) I also think the end number relies heavily upon getting the proper tune dialed in.

You could also bore and stroke it. (More intensive)
 

High Five H2

Well-Known Member
Messages
1,627
Location
West Texas
head/cam is an easy way to get power. bore/stroke, too, but by the time you get to a displacement past 6.0L you've spent way more than a complete 6.0L. these aluminum blocks can't be bored as much as the iron ones, either. i think the farthest I'd go with an aluminum 5.3 is mild heads and cam, plus all the bolt-ons and a tune.
 

SuperBuickGuy

Well-Known Member
Messages
3,403
Location
Woodinville, WA
You can get 1000 hp out of a 5.3, and you'd hate it as much as you'd hate 400 hp - small displacement only makes power at the upper end of the rpm scale. Worse, you lose hp and torque at the bottom end. Get a truck 6.0 and build it, 400 is easy and your vehicle stays running while you put the motor together. Best of all, everyone and their brother want aluminum 5.3s for their 1000 hp mustang builds - so they are quite valuable.
 

adventr

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Messages
500
Location
United States
Just found this thread.


For anyone researching in the future, the heads that come on the H3 5.3L V8 (LH8 engine) are 243/799 castings. Regarded to be some of the best flowing heads ever used on the LS engines, and are highly sought after. Same heads can also be found on the 03-04 Z06 corvette (those had sodium filled lightweight valves though).
All in all, I'd so a simple cam swap and some tuning, and it would really wake the 5.3 up.

Or, like what was mentioned before, find another engine to build and then just swap yours out. For the most part, all LS engines (4.8/5.3/6.0/6.2) are identical in size.


If you wanted to go crazy, a custom turbo setup would also wake that 5.3 up.... LOL
 

RamRod

Well-Known Member
Messages
3,914
Location
AB, Canada
I think if you wanted a little extra I would get some custom headers, true dual exhaust, high flow air intake and maybe a cam.... then get it tuned and call it a day.

If you want more than that I would just go straight to the Supercharger! Bolt on, tune, and go
 

amrg

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2,317
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Qatar
The GM 1500 trucks are able to run 400 hp at the wheels with exactly the above (headers, true dual, intake, cam and tune). Too bad none of those have been done (and documented) on an H3 yet!

This is for 1500 series truck, 400 hp and 375 tq, not bad at the wheels! That translates to roughly 480-500 hp at the flywheel (big improvement over the stock 300). For sure a set of headers will make the H3 perform much better!

https://m.youtube.com/watch?v=3nIaC3O663A
 

Steve

Member
Messages
15
Location
Michigan
Ive got a rv cam in my T, airdoc, and borla catback. Pcm of nc tune. Large performance upgrade with the cam. No official dyno tests, but easy 30-40 hp more than stock based on the butt dyno... And it sounds way better too
 

High Five H2

Well-Known Member
Messages
1,627
Location
West Texas
Ive got a rv cam in my T, airdoc, and borla catback. Pcm of nc tune. Large performance upgrade with the cam. No official dyno tests, but easy 30-40 hp more than stock based on the butt dyno... And it sounds way better too
how's the gas mileage with the cam?
 

amrg

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2,317
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More info on the cam swap please! Hows the torque down low? More or less?
Oh and, vidz or it didnt happen!
 

Steve

Member
Messages
15
Location
Michigan
Fuel economy was crappy at first, but after a few hundred miles it got better. I think with the reprogram it had to relearn the long term fuel trim. Im probably back in the low to mid teens driving 70ish, and a bit better driving 55. All on 87 octane. I can do a video... But there isnt much to see as its all internal... I could take a photo of my old cam and valve springs sitting on a workbench...? Maybe a 0-60 run if i think about it so others can compare their times. My t is on the heavy side- snug top, ucp, predator winch mount with 8k winch, and currently a full tank of gas- all add up, so the extra hp is quite welcome. Ill try to do a run tomorrow morning if i remember to, then i get to figure out how to upload it here...
 

amrg

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Sorry wasnt specific, usually a cam swap makes the truck sound lumpy so wanted to hear it. Any specs on that cam? Anything that improves the torque from standstill is welcome in our heavy vehicles (how often do we stay in the 4500+ RPM range)
Did you dyno tune or pcmofnc mail order?
 

Steve

Member
Messages
15
Location
Michigan
Competition cam p/n 189-400-13 along with new beehive valve springs and a cam phase limiter. I think you only need the phase limiter for the 2010's, which is thr first year for vvt in the h3 alpha.

Its a little lumpy at idle. Enough that if i let it idle long enough in winter to warm up (like 15 min) it occaisionally sets a cel for random multiple misfires, even though it is running fine. Im sure this could be fixed if i had the time and desire to email pcm of nc, but its only a problem in winter when i leave it running too long... I did an email tune, a dyno would be better for sure but nobody in town has one.

i do have a video of a 0-60 run on my phone from my way in to work yesterday morning but dont know how to get it on the ipad and upload it here yet. I will try go get a decent idle sound byte on my phone, then maybe see if i can teach myself how to get it here...

definitely much better grunt at lower rpms with this cam and tune, i dont care so much about high revs either.

no head upgrades at all, gotta draw the line somewhere, and im pretty happy with how it goes now. I wont have the opportunity to take the time to learn to post video here till next week, stay tuned... And i may fail at this, so no promises
 

adventr

Well-Known Member
Messages
500
Location
United States
Competition cam p/n 189-400-13 along with new beehive valve springs and a cam phase limiter. I think you only need the phase limiter for the 2010's, which is thr first year for vvt in the h3 alpha.

Its a little lumpy at idle. Enough that if i let it idle long enough in winter to warm up (like 15 min) it occaisionally sets a cel for random multiple misfires, even though it is running fine. Im sure this could be fixed if i had the time and desire to email pcm of nc, but its only a problem in winter when i leave it running too long... I did an email tune, a dyno would be better for sure but nobody in town has one.

i do have a video of a 0-60 run on my phone from my way in to work yesterday morning but dont know how to get it on the ipad and upload it here yet. I will try go get a decent idle sound byte on my phone, then maybe see if i can teach myself how to get it here...

definitely much better grunt at lower rpms with this cam and tune, i dont care so much about high revs either.

no head upgrades at all, gotta draw the line somewhere, and im pretty happy with how it goes now. I wont have the opportunity to take the time to learn to post video here till next week, stay tuned... And i may fail at this, so no promises


Download the Youtube App for your phone, and set yourself up with a free account. From that point, you can just upload your videos from phone directly to Youtube. Then you can share the Youtube links on any forum!
 

5gn-h3t

Well-Known Member
Messages
616
Location
Northeast Pennsyltucky
I just put a cam in my H2 and it made a big difference. It is time consuming but I think it's worth it. Like others have said, I wouldn't do much more than cam/intake/exhaust on the 5.3. I would do a 6.0 or 6.2 for a big power upgrade. If I still had my CE, I definitely would have done a cam and/or swap.
 

5gn-h3t

Well-Known Member
Messages
616
Location
Northeast Pennsyltucky
For the record, my CEL is off and I don't have any problems with it. It's all about the tuning. The reason I ended up installing a cam was because of a random misfire code. I changed everything I could before pulling the engine. All 16 of my lifters were stuck at various positions in their travel. Agh!!! I don't know how the thing ran so well. I figured while I was in there, I might as well go big or go home. I replaced the cam, valve springs, pushrods, lifters, a few cooked rocker arms, and milled the heads.
 

humvee

Well-Known Member
Messages
507
Location
Doha, Qatar
Competition cam p/n 189-400-13 along with new beehive valve springs and a cam phase limiter.

I know its been a while since this happened, but could you share either a link or part number for the beehive valve springs? and the cam?
I'm thinking of camming the 5.3 (2009 model) and struggling to find the right parts.

Thanks
 

Steve

Member
Messages
15
Location
Michigan
The cam was from competition cam. Google comp cam and you get their website. The part number is 189-400-13. The springs are just the ones they recommended i dont know the part number. Very helpful folks, i just emailed them or called them and they hooked me up. I did get my cel issue resolved with a quick email to pcm of nc. Great people there, too. My T is running great still, just switched to winter wheels and tires. :( snow is coming
 

humvee

Well-Known Member
Messages
507
Location
Doha, Qatar
Thanks Steve! Will do. You gave me confidence knowing you didn't run into any issues till now.

Good luck with the snow :)
 
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