another 400sb thread

[borton]

found a 400 block and crank for 200, plans are to build it, slap a tbi on it, and have a torque curve that peaks around 2800 rpm, with around 400ft lbs, and 450 or so hp, more is always better, but on a budget and don't want to get two exotic, want to keep it reliable. emissions are not an issue, It will be going in front of a 700r4, I've got a 350 I can pull the rods from, any suggestions on pistons? would like to be able to run 87-91 pump gas I was planning on using some vortec heads, to get better power and mileage, any thoughts on which ones? will it mess with the tbi computer to not have an egr valve? or can I have a chip burned that will allow the deletion of it? I will have to have one burned for it since it is coming off a 350. from what I've read, I'll need a 454 tbi, and an intake with 2" holes for that tbi, in the vortec form, I believe I'm down to a edelbrock perforer.

[five7kid]

Welcome aboard thirdgen.org.

First, the basics on your block: Is it stock bore? If not, how much is it overbored and are the cylinders still clean? If not, then have the cylinder walls sonic tested for thickness to ensure they can take the next overbore to clean-up. If it has been bored, and the cylinder walls need to be bored again, most likely you've got yourself a $200 boat anchor. Ditto if you don't have it checked for cracks before you put down the 200 bones.

Next, budget and exotic - TBI is not the former and for a 400, it will turn into the latter. A simple carb will meet both objectives - budget and simple.

If you stay with TBI, yes, 454 TB. No, not a TBI 2-hole intake. Get a 4bbl intake and a TBI adapter. And, you don't pay to get a chip burned, you get the equipment for about what a custom chip will cost you and learn to do it yourself. And program out the EGR valve.

Finally, your torque/HP goals - unrealistic. HP = torque at 5252 RPMs (that's just the way the math works). If you want 450 HP, at 5252 RPMs you'll need 450 lb-ft of torque. If you want 450 HP at less than 5252 RPMs, you'll need more than 450 lb-ft of torque. 400 lb-ft peak at 2800 RPMs will not yield 450 HP.

And, with a stock factory 400 block, more is seldom better. . .

[borton]

Originally Posted by five7kid

Welcome aboard thirdgen.org.

thanks

First, the basics on your block: Is it stock bore? If not, how much is it overbored and are the cylinders still clean? If not, then have the cylinder walls sonic tested for thickness to ensure they can take the next overbore to clean-up. If it has been bored, and the cylinder walls need to be bored again, most likely you've got yourself a $200 boat anchor. Ditto if you don't have it checked for cracks before you put down the 200 bones.

owner sais its a stock bore, having a friend check it out its only a 3 hour drive away for me

Next, budget and exotic - TBI is not the former and for a 400, it will turn into the latter. A simple carb will meet both objectives - budget and simple.

If you stay with TBI, yes, 454 TB. No, not a TBI 2-hole intake. Get a 4bbl intake and a TBI adapter. And, you don't pay to get a chip burned, you get the equipment for about what a custom chip will cost you and learn to do it yourself. And program out the EGR valve.

I've got the tbi system, and have more patience with a laptop than I do trying to jet a carb, then to find out I've got it lean going up the 10,000 foot pass to jackson hole, then rich heading south.

Finally, your torque/HP goals - unrealistic. HP = torque at 5252 RPMs (that's just the way the math works). If you want 450 HP, at 5252 RPMs you'll need 450 lb-ft of torque. If you want 450 HP at less than 5252 RPMs, you'll need more than 450 lb-ft of torque. 400 lb-ft peak at 2800 RPMs will not yield 450 HP.

And, with a stock factory 400 block, more is seldom better. . .

so say 400hp at 5252 rpm puts the torque at 400, where is the peak?

[borton]

what is the stock bore for a 400sb, 4.125?

[TON*LOC]

i'm not tring to still your thread but you can just take off all the stuff off the tpi and tbi motors and transfer it over to a 400 botom end ?? if so then i'm with this guy ! seems like the thing to do

[Codename 47]

I'd make sure it's a 2 bolt block. That's the way to go if you really plan on staying with the block and maybe upgrading down the road.

Hey five7kid,
I have a 400 bored .060 over. Can this cause cooling problems?

[Randy82WS7]

hey there yeah you can swap over the FI top end onto the 400sb bottom end but you will have to find a way to attach a knock sensor to the block

in which there was no provision for before 1980

there will be some other issues trying to put FI on an old 400 or any other engine before 79 especially,


i would really look at going with carb fuel system on it to save headaches, costs, and time, and many other troubles,


but each to their own


good luck

[F-Body Demon]

+1 for the Carb setup. I have a 400 in my 85 T/A. I spent $80 on my manifold (victor jr. Ebay) and 200 for a 780 Holley Vac secondary. So look at $300 for your intake...not bad IMO. And I make power all the way to 6200 with the tq peaking at like 3200, but thats on the butt dyno.

As for the rods and pistons, I went with 5140 Eagle cap screw rods for $200 and Speed pro hyper-u's for $200 (again Ebay) then stock crank polished $25 and stock balancer, Speedway flexplate $25 balanced for $150 so I spent 600 for the rotating assy. Then Block prep and bearings were $400 for align hone, boring with plates and clevite 77s. Total shortblock was 1g and it runs like a SOB. But that could also be the AFRs lol.

Which brings me to the Vortecs, I swear man just save up the rest for some AFR 195 Eliminators and you will be VERY happy $1400 isnt that bad. And I have no problem pulling STRONG to redline.

[five7kid]

Originally Posted by Randy82WS7

... you will have to find a way to attach a knock sensor to the block

in which there was no provision for before 1980

Baloney. It's been there on every SBC block since 1955. It's the water jacket drain hole.

The stock bore of a 400 is 4.125".

The problem with thin cylinder walls is they break. The more power you make, the sooner they'll break.

400 lb-ft torque at 5252 RPMs most likely means peak torque is below that, probably in the 4000-4500 range. Peak power will probably be a little over 5252 RPMs. It's all in the cam, induction, and exhaust. It's not unreasonable to expect 450 lb-ft torque and 400+ HP from a 400, though. With the right heads and induction.

If you really want to stick with TBI, there isn't a TBI head out there that is up to the task. But, decent Vortec heads, a good Vortec intake manifold, and proper TBI equipment will get you there. Look on the TBI forum for the budget TBI engine sticky. Everything applies to you (except roller lifter cam), you just have 50 more cubic inches to feed and play with. There's nothing fundamentally wrong with TBI, it was just never developed by the factory as a performance system, and the aftermarket hasn't stepped up to the plate. However, Holley has a 4-bbl TBI stand-alone EFI system, so it can't be all that bad.

[borton]

as far as the heads go, I'd like a vortec head, not sure what the benefits would be, I'd like good mileage with the power, but if I'm better off with a better flowing non vortec head, is that the route to take?

is there a vortec head that would out perform this dart 10621122:
Brand:Dart
Product Line:Dart Iron Eagle Platinum Cylinder Heads
Cylinder Head Style:Assembled
Cylinder Head Material:Cast iron
Cylinder Head Finish:Natural
Combustion Chamber Volume (cc):72
CNC Machined Combustion Chamber:No
Intake Runner Volume (cc):215cc
Exhaust Runner Volume (cc):75cc
CNC Machined Intake Runner:No
CNC Machined Exhaust Runner:No
Combustion Chamber Style:Heart
Intake Port Location:Standard
Exhaust Port Shape:Square
Exhaust Port Location:Standard
Spark Plug Style:Straight
Intake Valves Included:Yes
Intake Valve Diameter (in):2.050 in.
Exhaust Valves Included:Yes
Exhaust Valve Diameter (in):1.600 in
.Valve Springs Included:Yes
Maximum Valve Lift (in):0.620 in.
Outside Diameter of Outer Spring (in):1.437 in.
Damper Spring Included:No
Number of Springs Per Valve: Dual
Retainers Included:Yes
Retainer Material:Steel
Locks Included:Yes
Lock Style:10 degree
Valve Stem Seals Included:Yes
Valve Stem Seal Style:PC seal
Rocker Arm Studs Included:Yes
Rocker Arm Nut Thread Size:3/8-24 in.
Rocker Arms Included:No
Rocker Arm Nuts Included:No
Guideplates Included:Yes
Guideplate Pushrod Size:5/16 in.
Valve Cover Mounting Style:Center and perimeter bolt
Accessory Bolt Holes Drilled:Yes
Intake Valve Angle:23
Exhaust Valve Angle:23
Valve Guides Included:Yes
Valve Guide Material:Manganese bronze intake/Phosphorous bronze exhaust
Valve Seats Machined:Yes
Valve Seat Machine Style:4-angle intake/3-angle exhaust
Valve Seat Material: Ductile iron
Steam Holes Drilled:No
Oiling Style:Through pushrod
Machined for O-Ring:No
Heat Crossover:No





or the aluminum version #11621122
Brand:Dart
Product Line:Dart Pro 1 Aluminum Cylinder Heads
Cylinder Head Style:Assembled
Cylinder Head Material:Aluminum
Cylinder Head Finish:Natural
Combustion Chamber Volume (cc):72
CNC Machined Combustion Chamber:No
Intake Runner Volume (cc):215cc
Exhaust Runner Volume (cc):75cc
CNC Machined Intake Runner:No
CNC Machined Exhaust Runner:No
Combustion Chamber Style:Heart
Intake Port Location:Standard
Exhaust Port Shape:Square
Exhaust Port Location:Standard
Spark Plug Style:Straight
Intake Valves Included:Yes
Intake Valve Diameter (in):2.050 in.
Exhaust Valves Included:Yes
Exhaust Valve Diameter (in):1.600 in.
Valve Springs Included:Yes
Maximum Valve Lift (in):0.620 in.
Outside Diameter of Outer Spring (in):1.437 in.
Damper Spring Included:No
Number of Springs Per Valve: Dual
Retainers Included:Yes
Retainer Material:Steel
Locks Included:Yes
Lock Style:10 degree
Valve Stem Seals Included:Yes
Valve Stem Seal Style:PC seal
Rocker Arm Studs Included:Yes
Rocker Arm Nut Thread Size:3/8-24 in.
Rocker Arms Included:No
Rocker Arm Nuts Included:No
Guideplates Included:Yes
Guideplate Pushrod Size:5/16 in.
Valve Cover Mounting Style:Center and perimeter bolt
Accessory Bolt Holes Drilled:Yes
Intake Valve Angle:23
Exhaust Valve Angle:23
Valve Guides Included:Yes
Valve Guide Material:Manganese bronze
Valve Seats Machined:Yes
Valve Seat Machine Style:4-angle intake/3-angle exhaust
Valve Seat Material: Ductile iron
Steam Holes Drilled:NoOiling Style:Through pushrod
Machined for O-Ring:No
Heat Crossover:No

[five7kid]

For a nice streetable 400, Vortecs upgraded for a little higher valve lift will do fine.

If you're going to try for the 500+ hp range, then the bigger heads would be in order.

There are bigger Vortecs available now.

[vorgath]

Glad I read this thread, didn't even think of how and if you can use a knock sensor on a 400 block.

[five7kid]

I can't claim intimate knowledge of knock sensor theory, but I understand they are "tuned" to different bore diameters (has to do with how long it takes sound to bounce off the cylinder walls, from what I can understand). The factory never made an engine with the 400-size bore with a knock sensor. To the best of my knowledge, neither has the aftermarket.

For what it's worth. I have also seen the same knock sensor part number on both 305 and 350 applications, which have different bore diameters.

So, I'm not sure what to think.

[borton]

Originally Posted by five7kid

For a nice streetable 400, Vortecs upgraded for a little higher valve lift will do fine.

If you're going to try for the 500+ hp range, then the bigger heads would be in order.

There are bigger Vortecs available now.

I guess the cam and rockers would determine what kind of valve lift I need, but for that nice streetable 400, not to wild of cam, its still going to need to not mess with said knock sensor and computer, in vortec with say .530 max lift, 2.00 intake valves, 1.55 exhaust, 65cc combustion chanber, 206cc intake, and 77cc exhaust runner volume sound good?

how do I figure where my compression is going to be?
what I know, 400 block, will be bored 30, 5.7 rods, Hypereutectic dish +12.5cc #STL-H615CP30, head mentioned above.

[84z28350]

Originally Posted by five7kid

I can't claim intimate knowledge of knock sensor theory, but I understand they are "tuned" to different bore diameters (has to do with how long it takes sound to bounce off the cylinder walls, from what I can understand). The factory never made an engine with the 400-size bore with a knock sensor. To the best of my knowledge, neither has the aftermarket.

For what it's worth. I have also seen the same knock sensor part number on both 305 and 350 applications, which have different bore diameters.

So, I'm not sure what to think.

Sensor could still be the same. Just a difference in the programming in the ECM that determins what is a knock and whats not...

[cc 82Z-28]

The 400 I am getting parts for is completely stock, it has new pistons, rings, bearings, and ARP hardware in the bottom end. The bore is stock 4.125" the stroke is 3.750" with the stock 400 rods, and the piston sits .025" in the hole with -16cc dish pistons. With the aluminum 62cc heads I am going to run, my compression figures to be around 9:95:1 with a .038" head gasket. Mine is a 75 2 bolt main block. It should be a runner, I hope..