Author Topic: My 347 LSx Build Thread  (Read 1120 times)

77 TA man

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My 347 LSx Build Thread
« on: January 21, 2018, 08:32:17 PM »


So my base block is a year 2000 GM 4.8/5.3 Vortec block, based on the crank casting number it is a 5.3 liter engine, this is important because the 5.3/5.7 and 6.0 LS engines all share the same crank and rods. What I did was take the 96mm bored 5.3 block and bored it out to slightly bigger than the LS1(99mm or 3.898") bore at 99.187 or 3.905" which is essentially safe max bore on a 4.8/5.3 block.

The night I tore it down it was locked up, I was replacing rods and pistons anyway so it got beat apart with a sledgehammer over the course of 4 hours. I believe it had been flooded at one point given the fine layer of sediment all over the engine which was very similar to the interior of flooded cars that I have seen. Rods, pistons, cam, lifters, pushrods all went in the scrap pile when I took it apart along with the cast aluminum truck oil pan which was cracked front to back.

I'll try to find a picture but the top of Intake valves actually rusted to seat leaving behind a wall of rust when I tapped the valves out. It's an aluminum head too.

I did the standard tear down of block plugs, cam bearings etc... It was then ovened and steel shot blasted removing all shît from the block. Since I was upgrading my main cap hardware with ARP studs I had to do an align hone, cut the main caps and I aimed for the exact middle of my OE main bore spec. Since the LS series have side bolt mains you have to watch exactly how much you cut off or you won't be able to install your side bolts. I did not have this problem but the align hone was very time consuming. My stock windage tray wouldn't clear the ARP studs so I had to drill out 3 holes using a Bridgeport drill press.

My next step was decking the block, I went from a 9.240" factory deck to where it cleaned up at 9.228" deck.

When I bored the block out I went from a 3.7xx bore to a 3.905" bore. Roughly 0.120" or 0.125" I don't remember exactly now but it's close enough for the hone to finish it out. I do the final hone tomorrow to match the block to my $720 Forged -25cc dished pistons. Almost all of The Wiseco pistons measured in at 3.9017" with one being exactly 3.902". I have also elected to use the ARP head studs and bought 4340 forged rods with 200,000psi bolts and will be using the 0.010 turned factory crank.
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Wiseco's recommendation for clearance was .0035" but since this will be turbo'd(=Hot AF) the instructor thought that an additional clearance of .002 would be needed. This will bring the finished bore out to 3.9071 or there abouts. Given the .0004(4 tenths) difference between the measured pistons we are going to mate each piston to it's bore.

I lubed the rod bolts and torqued to the spec for the 2,000 series bolts (70 FT/IB), and checked them with a rod gauge. They are in spec at between 2.2247"-2.2249". I've got the rods marked in sharpie with 1-8 with their actual spec wrote on them but that's more for reference than what cylinder that rod will go to.

I recieved my Summit Racing order of Durabond High performance cam bearings for the LS(they switched cam bearing sizes IIRCows in 2004 when they went to same length head bolts as well or maybe in '06 or '07 when they went with the Gen 4 LS. Either way it doesn't matter since my block is an early Gen 3) I also ordered a LS2 timing chain which is stronger than a stock truck timing chain, and Sealed Power 2.00" intake valves that are stock replacement for a 5.7/6.0 and was sorely disappointed, valve faces were rough and uneven with the margins being way too thin and razor sharp. I will probably front the dough and go with Manley Race-Flow valves in 2.00" and 1.57" Rev valves  to replace my unusable stock 1.89" intake valves and my stock 1.55" exhaust valves of which there was one that had a rotted face/margin and one was ever so slightly bent.

My main and rod bearings are on the way and should be here next week, they are King bearings.

I have also ordered the BTR Stage 2 Turbo cam and will match it up with their .660 spring kit when I get around to getting the heads done.

I punched out my stock rocker arm trunnions and glass bead blasted both the rockers and the rocker shafts.
My aluminum valve covers and front cover were bead lasted as well and painted in GM Bahama Blue.

  This brings us up to current and I hope to finish the rest of the cylinder hone tomorrow evening.

 Questions and comments welcome! Thanks for reading
1977 HardTop T/A: 347 LSx Build,3.905" Wiseco 25cc dished pistons,forged rods, OE crank,BTR Stage 2 turbo cam, ARP Main+Head Studs,

1986 T-Top T/A:
Navy Blue Paint ,Grey/Black interior,140mph speedo,overhead console, LB9/Automatic, 2.77 Posi,  WS-6 suspension, All power options, UMI Wonderbar, UMI Rear LCAs, KYB Excel-Gs, Opened Formula hood,

ryeguy2006a

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Re: My 347 LSx Build Thread
« Reply #1 on: January 22, 2018, 11:55:37 AM »
Sounds like a sweet build man. More info on the turbo setup? What car are you putting it in?

1976 Trans Am LS1, 6 speed, C5 12.8" Brakes, LS1 rear 12" brakes, 17" Aluminum Rims, and much more...SOLD
My Build: http://transamcountry.com/community/index.php?topic=24465.0

New project: 1968 Camaro with 6?.?0?  5.3 w/ Z06 cam/T56
http://transamcountry.com/community/index.php?topic=74591.0

Hutchman

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Re: My 347 LSx Build Thread
« Reply #2 on: January 22, 2018, 06:35:35 PM »
The WS6 store has a new line of budget stainless valves that might work:

http://www.ws6project.com/user_stor/catalog/valves/

Might be worth  a looksee!

77 TA man

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Re: My 347 LSx Build Thread
« Reply #3 on: January 22, 2018, 10:50:30 PM »
Sounds like a sweet build man. More info on the turbo setup? What car are you putting it in?


I don't have the turbo stuff yet, but I'm planning on about 10psi from an On3 78/75, it seems most LSx turbo guys are doing a 7xmm turbo.  Most of my combo is from taking stuff that works for other guys and applying it to my build.   This will go In my 1977 T/A project, I'll probably run a 3.55 gear in the modified OE 10 bolt. Current trans/gear is a TH-350 with a 3.23 but I'll do either a 4L80E or preferably a T-56 when funds allow.  I am open to any recommendations as to turbo selection or other areas of the project!

The WS6 store has a new line of budget stainless valves that might work:

http://www.ws6project.com/user_stor/catalog/valves/

Might be worth  a looksee!
Thanks! That'll Definitely help when I get around to the heads.
I finished up the final hone tonight so block machining is done!
1977 HardTop T/A: 347 LSx Build,3.905" Wiseco 25cc dished pistons,forged rods, OE crank,BTR Stage 2 turbo cam, ARP Main+Head Studs,

1986 T-Top T/A:
Navy Blue Paint ,Grey/Black interior,140mph speedo,overhead console, LB9/Automatic, 2.77 Posi,  WS-6 suspension, All power options, UMI Wonderbar, UMI Rear LCAs, KYB Excel-Gs, Opened Formula hood,

Box

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Re: My 347 LSx Build Thread
« Reply #4 on: January 22, 2018, 11:08:36 PM »
Nice to see you back and tackling things again.  As far as the turbo goes 76mm seems about right if you're going single, I'd definitely recommend a twin scroll ball bearing turbo at any rate.  Garrett, BorgWarer, Precision Turbo, etc... are all good choices, though BorgWarner are generally the least expensive.  Or if you're all about that JDM life there's Tomei, HKS, GReddy, and Tomioka.

1996 Pontiac Firebird Formula hardtop 6-speed

Re: My 347 LSx Build Thread
« Reply #4 on: January 22, 2018, 11:08:36 PM »

FormTA

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Re: My 347 LSx Build Thread
« Reply #5 on: January 23, 2018, 06:01:08 AM »
I'm sure you know but make sure you set your rings up a bit looser for you turbo set up.
79 Trans am 301 (work in progress) LS swap n progress
79 Formula 301 (Work in progress)
67 RS Camaro (Work in progress)
See the recurring theme???

77 TA man

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Re: My 347 LSx Build Thread
« Reply #6 on: January 27, 2018, 08:01:32 PM »
The WS6 store has a new line of budget stainless valves that might work:

http://www.ws6project.com/user_stor/catalog/valves/

Might be worth  a looksee!
I went ahead and ordered the 2.00 intakes and the 1.571 exhaust and will report on them when they show up.
1977 HardTop T/A: 347 LSx Build,3.905" Wiseco 25cc dished pistons,forged rods, OE crank,BTR Stage 2 turbo cam, ARP Main+Head Studs,

1986 T-Top T/A:
Navy Blue Paint ,Grey/Black interior,140mph speedo,overhead console, LB9/Automatic, 2.77 Posi,  WS-6 suspension, All power options, UMI Wonderbar, UMI Rear LCAs, KYB Excel-Gs, Opened Formula hood,

Hutchman

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Re: My 347 LSx Build Thread
« Reply #7 on: January 28, 2018, 12:04:50 AM »
The WS6 store has a new line of budget stainless valves that might work:

http://www.ws6project.com/user_stor/catalog/valves/

Might be worth  a looksee!
I went ahead and ordered the 2.00 intakes and the 1.571 exhaust and will report on them when they show up.

Looking forwards to hearing what you think of them.  We  used generic stainless valves inour injected dragster back in the 80s.  It went 8 teens@160, so they seemed to work!

77 TA man

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Re: My 347 LSx Build Thread
« Reply #8 on: February 15, 2018, 06:55:49 AM »

These are the flow numbers for my unmodified 862s with stock valve size.

Int-       CFM-
.100"-  63.1
.200"-134.3
.300"-183.4
.400"-210.4
.500"-230.5
.600"-228.8
.700"-236.1

Ex-       CFM
.100"- 55.3
.200"-104.4
.300"-139.5
.400"-173.7
.500"-198.2
.600"-212.2
.700"-217

  Looking at these numbers more closely it appears the intake slows down at around .500 lift and the exhaust  slows down at .600 lift.    Since I'm running a .600 lift turbo cam this is of interest to me.  I guess the next step is do a valve job with the 2.00" intakes and 1.571" exhausts and see what I get. 
1977 HardTop T/A: 347 LSx Build,3.905" Wiseco 25cc dished pistons,forged rods, OE crank,BTR Stage 2 turbo cam, ARP Main+Head Studs,

1986 T-Top T/A:
Navy Blue Paint ,Grey/Black interior,140mph speedo,overhead console, LB9/Automatic, 2.77 Posi,  WS-6 suspension, All power options, UMI Wonderbar, UMI Rear LCAs, KYB Excel-Gs, Opened Formula hood,

ryeguy2006a

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Re: My 347 LSx Build Thread
« Reply #9 on: February 16, 2018, 01:54:28 PM »
Since you are doing a rebuild anyway, there are several DIY tutorials on how to do a little bowl cleanup and pick up some pretty decent flow numbers for pretty cheap. May want to look into that.

1976 Trans Am LS1, 6 speed, C5 12.8" Brakes, LS1 rear 12" brakes, 17" Aluminum Rims, and much more...SOLD
My Build: http://transamcountry.com/community/index.php?topic=24465.0

New project: 1968 Camaro with 6?.?0?  5.3 w/ Z06 cam/T56
http://transamcountry.com/community/index.php?topic=74591.0

Hutchman

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Re: My 347 LSx Build Thread
« Reply #10 on: February 16, 2018, 10:45:46 PM »
I think that stall flow is normal in the 862 head....very similar to what happens in the 241.  I have  241s on my car with a big ole sloppy cam which results in lazy performance in the mid range and less than what might be expected up top because of the choke in  heads and manifold.

There is a lot to be gained in opening up the bowl and a GOOD valve job.  From what I've read, a good head porter can really wake a set of heads up with the correct rework of the bowl area and valve job.  The 2" valves should help too!  There are several companies that offer rebuild/CNC services on customer supplied heads.

The 862s should have a 62 cc chamber and give about 11.5 to 1 compression on a 3.905 bore.  That ought to help with some low end torque.


70RAIV455

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Re: My 347 LSx Build Thread
« Reply #11 on: February 16, 2018, 11:13:35 PM »
The On 3 Turbo kits are just Ok.
Fitment leaves alot to be desired.
I have installed 2 On3 Turbo kits on Ford Mustangs.
Results were pretty good.

Your better off building the Entire turbo layout on your own if you can. Tig weld it all together.
Run the largest Intercooler you can fit.

Hutchman

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77 TA man

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Re: My 347 LSx Build Thread
« Reply #13 on: February 17, 2018, 02:16:01 PM »
 
  My valves came in some time ago and I must say that I really like them, they are the RPM "Lead Foot" valves available at WS6 project.com. They are 2.00" intakes and 1.571" exhaust, they also are a one piece stainless valve with undercut stems and an extra thick (.0085") margin. The undercut stem is more noticeable on the Intakes with the exhaust being more of a swirl polish than an undercut.

  I was planning of self porting/bowl cleanup and will do heavy documentation as to modification and resulting changes in flow and it's behavior.     

   
The On 3 Turbo kits are just Ok.
Fitment leaves alot to be desired.
I have installed 2 On3 Turbo kits on Ford Mustangs.
Results were pretty good.

Your better off building the Entire turbo layout on your own if you can. Tig weld it all together.
Run the largest Intercooler you can fit.

  I was figuring the large open grills on the '77 nose would be a good place for an intercooler and an oil cooler but my whole car is apart right now so I can't do any measurements.   

  My block has been decked and the heads will need milled but I am hoping to be in the area of 8.5 static and about 11.2 compression at max boost with the Wiseco -25cc dish pistons and the 862s with a .040 headgasket.  I will check piston to deck clearance before I order headgaskets.  It's too late now, but do you guys think there will be any sluggishness off-boost caused by the lower compression?
1977 HardTop T/A: 347 LSx Build,3.905" Wiseco 25cc dished pistons,forged rods, OE crank,BTR Stage 2 turbo cam, ARP Main+Head Studs,

1986 T-Top T/A:
Navy Blue Paint ,Grey/Black interior,140mph speedo,overhead console, LB9/Automatic, 2.77 Posi,  WS-6 suspension, All power options, UMI Wonderbar, UMI Rear LCAs, KYB Excel-Gs, Opened Formula hood,

Hutchman

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Re: My 347 LSx Build Thread
« Reply #14 on: February 17, 2018, 02:57:29 PM »
I forgot you were running  a torbo.  How much compression can you run with the turbo?

Re: My 347 LSx Build Thread
« Reply #14 on: February 17, 2018, 02:57:29 PM »

ryeguy2006a

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Re: My 347 LSx Build Thread
« Reply #15 on: February 20, 2018, 10:59:20 AM »
Since you went with the dished pistons, you could also run a set of 243 heads and not bump the compression too much.

1976 Trans Am LS1, 6 speed, C5 12.8" Brakes, LS1 rear 12" brakes, 17" Aluminum Rims, and much more...SOLD
My Build: http://transamcountry.com/community/index.php?topic=24465.0

New project: 1968 Camaro with 6?.?0?  5.3 w/ Z06 cam/T56
http://transamcountry.com/community/index.php?topic=74591.0

77 TA man

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Re: My 347 LSx Build Thread
« Reply #16 on: April 14, 2018, 08:38:40 PM »
 So far I've got the bottom together,  I had issues with rod bolts barely scraping the truck windage tray so I had to clearance that.  I used the Fbody oil pan swap kit for the pan and pickup tube, the ARP main studs caused some fitting issues with the Fbody windage tray so I put the truck tray in its place and didn't have any tray to pan clearance issues.  I bought a Melling high pressure oil pump since my bearing clearances were on the looser side and didn't want any  loss once I put the oil cooler and turbo lines on.  I did use a oil pump girdle as well, not sure it was necessary but it did help spread things out evenly.

  I degreed the BTR stage 2 turbo cam in as close as it could get(+half a degree), I used GM performance LS2 trays I drilled either 3/8s or 7/16 oil drain holes in. I did one 1/2 hole and thought is was pretty huge so I downsized the rest of the holes. I used Morel 5315 lifters.

 I put spiraled engine tech valve guides in, and did some conservative port work on the 862s. I didn't have time to do a hefty port job so I just removed the swirl ramp on the intakes and blended everything I could together.  I'm working on cutting the seats for the bigger valves now.
1977 HardTop T/A: 347 LSx Build,3.905" Wiseco 25cc dished pistons,forged rods, OE crank,BTR Stage 2 turbo cam, ARP Main+Head Studs,

1986 T-Top T/A:
Navy Blue Paint ,Grey/Black interior,140mph speedo,overhead console, LB9/Automatic, 2.77 Posi,  WS-6 suspension, All power options, UMI Wonderbar, UMI Rear LCAs, KYB Excel-Gs, Opened Formula hood,

Box

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Re: My 347 LSx Build Thread
« Reply #17 on: April 15, 2018, 08:55:30 PM »
Wooo, progress!

1996 Pontiac Firebird Formula hardtop 6-speed

ryeguy2006a

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Re: My 347 LSx Build Thread
« Reply #18 on: April 16, 2018, 10:56:41 AM »
Yes, progress is good! Can you post some pictures of the port work? Would be cool to see before and after pictures.

1976 Trans Am LS1, 6 speed, C5 12.8" Brakes, LS1 rear 12" brakes, 17" Aluminum Rims, and much more...SOLD
My Build: http://transamcountry.com/community/index.php?topic=24465.0

New project: 1968 Camaro with 6?.?0?  5.3 w/ Z06 cam/T56
http://transamcountry.com/community/index.php?topic=74591.0

77 TA man

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Re: My 347 LSx Build Thread
« Reply #19 on: April 17, 2018, 06:24:27 PM »
Yes, progress is good! Can you post some pictures of the port work? Would be cool to see before and after pictures.
I just did a conservative port job, I figured less is more with my stick figure skill level porting skills.   My valves were slightly out of round and I had to lightly grind them to true them up.  Eh, that's not a big deal though.   
1977 HardTop T/A: 347 LSx Build,3.905" Wiseco 25cc dished pistons,forged rods, OE crank,BTR Stage 2 turbo cam, ARP Main+Head Studs,

1986 T-Top T/A:
Navy Blue Paint ,Grey/Black interior,140mph speedo,overhead console, LB9/Automatic, 2.77 Posi,  WS-6 suspension, All power options, UMI Wonderbar, UMI Rear LCAs, KYB Excel-Gs, Opened Formula hood,

ryeguy2006a

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Re: My 347 LSx Build Thread
« Reply #20 on: May 09, 2018, 10:35:31 AM »
Any updates?

1976 Trans Am LS1, 6 speed, C5 12.8" Brakes, LS1 rear 12" brakes, 17" Aluminum Rims, and much more...SOLD
My Build: http://transamcountry.com/community/index.php?topic=24465.0

New project: 1968 Camaro with 6?.?0?  5.3 w/ Z06 cam/T56
http://transamcountry.com/community/index.php?topic=74591.0

77 TA man

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Re: My 347 LSx Build Thread
« Reply #21 on: May 11, 2018, 05:43:16 PM »
Not yet,  I've got the intake seats cut for the bigger valves and my exhaust seats are done and seal right up.
1977 HardTop T/A: 347 LSx Build,3.905" Wiseco 25cc dished pistons,forged rods, OE crank,BTR Stage 2 turbo cam, ARP Main+Head Studs,

1986 T-Top T/A:
Navy Blue Paint ,Grey/Black interior,140mph speedo,overhead console, LB9/Automatic, 2.77 Posi,  WS-6 suspension, All power options, UMI Wonderbar, UMI Rear LCAs, KYB Excel-Gs, Opened Formula hood,

Re: My 347 LSx Build Thread
« Reply #21 on: May 11, 2018, 05:43:16 PM »
You can help support TAC!