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Old Iron 2.0

Sold/ traded the Vic Jr. intake thay I had on the LQ4 for a L31 Vortec that supposedly spun a rod bearing at right around 10k on the engine + an HEI dizzy and $150 on his end.

Found a 4 bolt main, 1 piece RMS long block local for $50 that I was supposed to pickup at 6:30 today but couldn't make it due to the 8.1 deal.

Getting it when I get back, I think it may be an L31 too.

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And you guys will probably hate me for this but I'm planning on running a carb on that 8.1.

Dart or Mast or someone makes a dual plane square bore intake for the 8.1 that you slap a carb on and drop a dizzy in.

Planning on putting a cam in too. Supposedly the 502 H.O. cam is nice in these or maybe get a nice cam kit from this company called Raylar.
 
Can't go with a 502 cam as the firing order is different from a normal bbc. It's the same as an LS. Raylar is the way to go if you want an 8.1 cam for sure. Only issue there is the torque curve jumps up at least 1000-1500 from factory. It will haul ass, but will be weak on torque below 2000 rpm.
 
Can't go with a 502 cam as the firing order is different from a normal bbc. It's the same as an LS. Raylar is the way to go if you want an 8.1 cam for sure. Only issue there is the torque curve jumps up at least 1000-1500 from factory. It will haul ass, but will be weak on torque below 2000 rpm.

If I went carbureted and used a distributor I can run that firing order from what I've read.
 
@ZooMad75 Will regular BBC front drive accessories work on the 8.1 Vortec?
You actually have the ideal setup for an 8.1 in a squarebody as it's from a medium duty. The 3/4ton/1 ton truck setup for a GMT800 truck has the a/c compressor running on a separate belt with the compressor down low on the passenger side of the block.

I don't think the earlier big block stuff matches up as the 8.1 has the water cross over that comes off the front of each head.
 
It would cost more to convert the 8.1 over than it would to just wire it.
It's missing all of the injection stuff minus the intake and throttle body.

No injectors, no fuel rails or any of that stuff.

No harness or computer, looked up the price for a pre-made stand alone harness for the 8.1 and that runs around $700 or so.

The Dart intake is between $500 - $600 which is pretty expensive + a $350 carb.

Needs headers regardless so some basic BBC long tubes... $200ish or so.

HEI Dizzy $100ish

I think I'll be into it cheaper with a carb than trying to piece the injection together and buying a harness.
 
That's not an L31 in the pictures.

Martin
It's a Vortec engine, got the center bolt Vortec heads unless I'm missing something.

I thought all the Vortec SBC's were L31's then again I don't know much about them.

The heads don't have some of the casting marks that I've seen on some of the Vortec heads.
 
Ironic twist.

I have an 8.1 harness complete minus a few cuts the JY did, and I need +4 52s.
I know everyone hates carbs nowadays and love fuel injection but I've always been partial to carbs in an old non daily driven truck.

I don't have to worry about a computer going bad, high pressure fuel pumps, AN fittings and fancy fuel line, big ol wire harness (even if it is a 3 or 4 wire hookup), no individual coils to worry about, knock sensors, map sensor, maf sensor etc.

HEI dizzy straight to the plugs, carburetor, jets and a screw driver.

I'm trying to keep everything as mechanical as possible. I may do electric fans but that's about it.

I can live with pumping the gas pedal and shitty cold starts lol.
 
Ironic twist.

I have an 8.1 harness complete minus a few cuts the JY did, and I need +4 52s.
And I'm gonna throw these 4" 52's out up front and see how it all looks.

My clapped out stock 52's up front are netting me around 4" of lift. Probably gonna put them on the weekend of the 7th.

With the 4" lift ones I'm gonna guess maybe 6" or so, I don't think I'll be sitting at 8" of lift with those up front especially when the 8.1 goes up there and a winch at some point.
 
it will be really tall.

I'm running 2" lift 52's without the overload and I have more than enough room for 40's to clear the top of the factory wheel opening.
 
It's a Vortec engine, got the center bolt Vortec heads unless I'm missing something.

I thought all the Vortec SBC's were L31's then again I don't know much about them.

The heads don't have some of the casting marks that I've seen on some of the Vortec heads.

It's 100% not a "Vortec". Chevrolet went to center bolt valve covers in the 80's. A Vortec head only has four intake bolts per head, not six like those. A Vortec head does not have an exhaust crossover. A Vortec engine would have a plastic timing cover with a cam sensor. A Vortec engine would have a roller cam.

That is an LO5 350 TBI (or an LO3 305), from an '87-'95 truck. A car would have a roller cam.

Martin
 
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