400sbc questions about vortec heads running tbi

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4thgentruck

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Here we go im wanting to run cast vortec heads casting #906. (I know ill need aftermarket springs retainers etc.) With a Weiand street warrior intake manifold. Xtreme energy comp cam complete kit w/ .490 lift. On top I'm wanting to run the tbi setup off of a 454. Stock 400 crank with stock length rods. With flat top pistons.

What are yalls thoughts and imputs on this set up? Is it even possible? And what hp/torque u think it will produce?

Thanks for any imput.
 

Jims86

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Here we go im wanting to run cast vortec heads casting #906. (I know ill need aftermarket springs retainers etc.) With a Weiand street warrior intake manifold. Xtreme energy comp cam complete kit w/ .490 lift. On top I'm wanting to run the tbi setup off of a 454. Stock 400 crank with stock length rods. With flat top pistons.

What are yalls thoughts and imputs on this set up? Is it even possible? And what hp/torque u think it will produce?

Thanks for any imput.

Possibly between 270 and 325 hp, TQ in the low to mid 300's...will need a tune though. vortec heads play some funky **** with OBD1 computers.
 

4thgentruck

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Darn I was hoping it would be more than that, but this is gonna be a daily driver. Do you think i shoulf use a diff computer or would it matter.
 

8T6K5

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Here we go im wanting to run cast vortec heads casting #906. (I know ill need aftermarket springs retainers etc.) With a Weiand street warrior intake manifold. Xtreme energy comp cam complete kit w/ .490 lift. On top I'm wanting to run the tbi setup off of a 454. Stock 400 crank with stock length rods. With flat top pistons.

What are yalls thoughts and imputs on this set up? Is it even possible? And what hp/torque u think it will produce?

Thanks for any imput.

Do it. Thats what I want to run with my TPI....
 

Green79Scottsdale

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Are you having the block machined? I ask because if you are taking it apart you might think about going to a 5.7" long rod. Stock on the 400's is only 5.565" (or there abouts). Doing this will create a better rod/stroke ratio and relieve some side force on the bores coming from the pistons. I figure since you are getting new pistons, you can allow for the longer rods by moving the wrist pin up in the piston. It's done with 383's all the time, so they can do it for your 400 pistons too.
 

4thgentruck

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Yes im taking apart the block and going with a 30 over bore making it a 406. Just using the stock crank. I would like to run the 5.700 rods and pistons. Was hoping for.more than 275 to 325 hp though.
 

Jims86

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Sounds dissapointing due to the current HP and Tq pissing match between the truck makers. Those figures willl light up the tires just fine. My TPI was putting out 230hp, and 406ft lbs with swirl ports, got 10-20 mpg hwy, and could pull a pretty good load.
 
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4thgentruck

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Thats good the main reason for the vortec heads and tb are for fuel economy. Just figure with the size of the motor plu vortec heads intake and cam choice it ould put out alil more than that. What do u think about rear ends. I want to go with disc rear brakes. Wanna stay chevy all the way. Will the 2000 era rearbend hold up to the 406 and 700r4 trans. Wanting 3.56 or 3.73 for better fuel milage and better highway rpm. Right now it has a gm 12 bolt truck axel with 4.10 gears
 

Jims86

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Thats good the main reason for the vortec heads and tb are for fuel economy. Just figure with the size of the motor plu vortec heads intake and cam choice it ould put out alil more than that. What do u think about rear ends. I want to go with disc rear brakes. Wanna stay chevy all the way. Will the 2000 era rearbend hold up to the 406 and 700r4 trans. Wanting 3.56 or 3.73 for better fuel milage and better highway rpm. Right now it has a gm 12 bolt truck axel with 4.10 gears

I wouldrecommend switching to a 4l80, and a TBI ECM from a 91K20 burb. I have had 6 700R 4s to date, and none of them lasted more than 2 or 3 years...no hot rodding, just normal driving.
 

4thgentruck

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Ok i was told to make sure it was a 30 spline input shaft cause the 27 shaft wouldnt hold up. But i will deff look into the 4l80 set up. Would the computer be able to run it. I know it will conect to the trans just wanna make sure.
 

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