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Old 07-08-2012, 07:55 PM   #1
luskeyclassics402
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Vortec Head Swap, What do I need?

Hey guys, I'm planning to do vortec head swap on my 88 k5 with the tbi setup, this is what I've gathered I need for it, please add on to this list if I'm forgetting something:
Vortec Heads
tbi/vortec intake
upgraded fuel pump
adjustable fuel pressure regualtor(not sure what psi yet)
bored out or bbc throttle body
gasket set
am I going to use original rockers or what should I do for that?
Please let me know!
Tucker
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Old 07-09-2012, 05:56 AM   #2
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Not sure on the mechanical part of the swap cause I've never done one in person.

But to reap the rewards you will need to tune the chip. Vortec heads have a completely different need for spark advance compared to TBI swirl port heads, or others for that matter... not to mention tune needs for bigger TB and fuel pressure.

While your at it look for a decent liquid filled in line gauge to go with your adjustable regulator. They are fairly cheap with bolt in adapter compared to a good fuel pressure tool gauge.

Pressure is a calculation based on engine HP output. As you change pressure you also need to change BPC/BPW in chip for proper tune. 13 PSI is accurate for these TBI motors. I don't care what GM said about 9 to 13, yes it will run, but not optimal unless 13 PSI.

There's already a factory built in fueling mistake on these ECM in chip of VE1 and VE2 adder adding up to over 100%, so ECM truncates back to 100%. Should never go over 95% when tuning... 85% is optimal.
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Old 07-10-2012, 10:19 PM
Posted in reply to eagle mark's post starting "Not sure on the mechanical part of the..."
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Quote:
Originally Posted by eagle mark View Post
Not sure on the mechanical part of the swap cause I've never done one in person.

But to reap the rewards you will need to tune the chip. Vortec heads have a completely different need for spark advance compared to TBI swirl port heads, or others for that matter... not to mention tune needs for bigger TB and fuel pressure.

While your at it look for a decent liquid filled in line gauge to go with your adjustable regulator. They are fairly cheap with bolt in adapter compared to a good fuel pressure tool gauge.

Pressure is a calculation based on engine HP output. As you change pressure you also need to change BPC/BPW in chip for proper tune. 13 PSI is accurate for these TBI motors. I don't care what GM said about 9 to 13, yes it will run, but not optimal unless 13 PSI.

There's already a factory built in fueling mistake on these ECM in chip of VE1 and VE2 adder adding up to over 100%, so ECM truncates back to 100%. Should never go over 95% when tuning... 85% is optimal.
Thanks! so are you saying i should run 13 psi for vortec heads then? I did plan on having a new prom burned, thinking about using tbichips.com, is he a good guy? let me know!
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Old 07-11-2012, 06:59 AM   #4
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Fuel pressure and BPW setting is a calculation of engines HP. So what should the engine put out is a detemining factor.

Get a local tuner who will do it hands on. Second choice is a tuner that will take your data logs and retune the initail starter chip he sent. Run, don't walk from any tuner selling you a perfect chip without a data log.
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Old 07-11-2012, 07:19 AM
Posted in reply to eagle mark's post starting "Fuel pressure and BPW setting is a..."
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you'll need to run a bypass hose from the top of the water pump to the front of the intake manifold too, without it you will get air pockets...also the vortec heads are set up for self aligning rocker arms, so a set of those should be aquired.
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Old 07-11-2012, 05:48 PM
Posted in reply to 76zimmer's post starting "you'll need to run a bypass hose from..."
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http://www.hotrodders.com/forum/vort...html#post46818
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Old 07-19-2012, 03:15 PM   #7
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alright, so ill get a gauge, and whats this about a water pump bypass? where would I run the hose on the water pump side? I'm a little confused on that... I just sold my stratus so ill be able to afford all of this now luckily!
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Old 07-19-2012, 03:48 PM   #8
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http://www.jegs.com/i/JEGS-Performan...59050/10002/-1

will this work for a regulator then?
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Old 07-19-2012, 03:56 PM   #9
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Here is some good info I've found looking for Vortec swaps:



From GM performance parts:
Any small block engine, regardless of year, that uses Vortec heads, will require an external coolant bypass line from the intake manifold to the 5/8" hose nipple on the water pump (passenger’s side). Suggested routing is from the 3/8 NPSF boss on intake manifold to the water pump."

Virtually all traditional small blocks have an internal bypass passage built in to the block and heads - except for the Vortec. This passage is the "3rd hole" on the passenger side of the water pump, below the lower water pump mounting bolt. The passage extends from the water pump diagonally through the block and through a hole in the head and head gasket. This passage gives you some coolant circulation while the thermostat is closed. The bypass hose on a traditional big block that runs from the top of the water pump to the intake manifold does the same thing for those.

If you have a Vortec block, Vortec heads, or a Vortec water pump, this passage does not function. So you must do something else.

Vortec engines originally installed in pickups from the factory have a BBC style bypass hose.

The bypass hose between the pump and the intake should work, just like it does on a BBC. Trouble is, some water pumps don't have a port there, and some intakes don't either.

So, another way to fix it is to drill holes in the periphery of the thermostat outer flange. This allows the same bypassing.

Symptoms of not having a functioning bypass are wild temperature swings on the gauge as the coolant warms prior to the thermostat opening. With no circulation at all in the block, as the coolant temperture approaches the thermostat set point, there is actually boiling occurring at the combustion chambers in the head. As soon as the thermostat opens, it all settles down.

Merely having heater hoses hooked up makes no difference. You need the circulation in the block and heads, not just circulation.

It doesn't suprise me that GM finally figured out that a bypass was needed and put it in their instructions. About time.

Here is a great article about putting Vortecs on an older block:
http://www.camaroperformers.com/cama...l/viewall.html

Vortec engines don't have a coolant bypass built into them like the older small blocks.

The old engines had a hole in the passenger side of the water pump (under the bottom bolt) that mated to the block and that hole routed water through the head to allow water to circulate when the thermostat is closed.

Vortec blocks as well as Vortec heads don't have those holes and some sort of bypass is necessary. The heater core will act as a bypass but if a heater valve is used, then it will cut off the flow.

Here are a couple pics showing the typical SBC cooling passage that allows the water pump to circulate through the block and head, which prevents the hot spots in the heads by continually circulating coolant, preventing the heads for getting hot before the block/manifold does.

The manifold pic is where the bypass should be hooked up, from the top of the water pump.
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RYOKEN: eesh, tonight, I'm contemplating 2 custom rear crossmembers and a $600 custom ss fuel tank.... what the F*CK is wrong with me?!?!?!!? :

CYBRFIRE: Nah, stainless is too brittle man. That would surely explode and kill you to death.
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Old 07-19-2012, 04:06 PM
Posted in reply to 76zimmer's post starting "Here is some good info I've found..."
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luskeyclassics402
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Quote:
Originally Posted by 76zimmer View Post
Here is some good info I've found looking for Vortec swaps:



From GM performance parts:
Any small block engine, regardless of year, that uses Vortec heads, will require an external coolant bypass line from the intake manifold to the 5/8" hose nipple on the water pump (passengerís side). Suggested routing is from the 3/8 NPSF boss on intake manifold to the water pump."

Virtually all traditional small blocks have an internal bypass passage built in to the block and heads - except for the Vortec. This passage is the "3rd hole" on the passenger side of the water pump, below the lower water pump mounting bolt. The passage extends from the water pump diagonally through the block and through a hole in the head and head gasket. This passage gives you some coolant circulation while the thermostat is closed. The bypass hose on a traditional big block that runs from the top of the water pump to the intake manifold does the same thing for those.

If you have a Vortec block, Vortec heads, or a Vortec water pump, this passage does not function. So you must do something else.

Vortec engines originally installed in pickups from the factory have a BBC style bypass hose.

The bypass hose between the pump and the intake should work, just like it does on a BBC. Trouble is, some water pumps don't have a port there, and some intakes don't either.

So, another way to fix it is to drill holes in the periphery of the thermostat outer flange. This allows the same bypassing.

Symptoms of not having a functioning bypass are wild temperature swings on the gauge as the coolant warms prior to the thermostat opening. With no circulation at all in the block, as the coolant temperture approaches the thermostat set point, there is actually boiling occurring at the combustion chambers in the head. As soon as the thermostat opens, it all settles down.

Merely having heater hoses hooked up makes no difference. You need the circulation in the block and heads, not just circulation.

It doesn't suprise me that GM finally figured out that a bypass was needed and put it in their instructions. About time.

Here is a great article about putting Vortecs on an older block:
http://www.camaroperformers.com/cama...l/viewall.html

Vortec engines don't have a coolant bypass built into them like the older small blocks.

The old engines had a hole in the passenger side of the water pump (under the bottom bolt) that mated to the block and that hole routed water through the head to allow water to circulate when the thermostat is closed.

Vortec blocks as well as Vortec heads don't have those holes and some sort of bypass is necessary. The heater core will act as a bypass but if a heater valve is used, then it will cut off the flow.

Here are a couple pics showing the typical SBC cooling passage that allows the water pump to circulate through the block and head, which prevents the hot spots in the heads by continually circulating coolant, preventing the heads for getting hot before the block/manifold does.

The manifold pic is where the bypass should be hooked up, from the top of the water pump.
Alright, makes sense, ill have to accomodate that then, next problem is how to go abbout increasing fuel pressure and how big of a throttle body should i go with, I've seen people use 454 throttle body with 350 injectors, will this work?
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