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Streetable 500HP 400 build

  
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Streetable 500HP 400 build

 
ksnuclear ksnuclear
New User | Posts: 3 | Joined: 01/11
Posted: 03/27/11
07:26 PM

Hi Everyone.

I hope all of you would be willing to give me some guidance on my project.

The car is a 69 Firebird that will be a mild restomod.  It will be mainly a weekend cruiser but I would also like to be able to drive Rt. 66 or drive to the Dream Cruise with confidence and reliability.  No trailers here!  It may also see the track from time to time but that would be rare.

It is my intention to install a TKO or Keisler RS 5 speed so I can have reasonable RPM at highway speeds.

I have a complete 1978 W-72 with 16X4s as a starting point.

What I want is about 500 HP and /or a nice big fat torque curve on pump gas.  My first question is do I have to block and crank to do this with?  I know the later 70s blocks were not as strong as the earlier but I have the 481988 block that is supposed to be stronger.  What’s the truth?

What about the heads?  I would think to achieve 500 hp it would be better to purchase the aluminum E heads rather that spend the cash on all the machine work for the 6Xs.  Will the Edelbrock heads get me to 500 out of the box?

OK, you know where I would like to go.  How do I get there?

Thanks!

John

PS Any Pontiac friendly machine shops in the Kansas City area?  

Pontiacman8 Pontiacman8
Moderator | Posts: 5779 | Joined: 02/08
Posted: 03/28/11
04:31 AM

The mid 1975&up 400 blocks have weaker mains and I would not recommend using it for the power out put you are wanting.

You will not see 500 HP out of those 6X heads.  
Engine builder,self taught auto body guy.
Horsepower sells engines and torque wins races

Pontiacman8
Pontiacman8
Pontiacman8

idrivejunk idrivejunk
Addict | Posts: 5172 | Joined: 12/09
Posted: 03/28/11
04:58 AM

I thought the 988 was the good block.  
idrivejunk

tuffnuff tuffnuff
Moderator | Posts: 2567 | Joined: 12/09
Posted: 03/28/11
05:42 AM

Roland Racing has a set of CV-1 heads that are canted valves and good for .800" lift.
With the right cam and induction system.,. 500 horse should be no problem.
The basic head price starts at $2995 for a pair.
This will not be a cheap build.
Here is the link, check it out.

http://www.highperformancepontiac.com/tech/hppp_0802_high_flow_pontiac_cylinder_head_packages/roland_racing.html

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

Pontiacman8 Pontiacman8
Moderator | Posts: 5779 | Joined: 02/08
Posted: 03/28/11
06:00 AM

The 481988 is the stronger 400 block was made from 1970-1975, midyear GM introduced the weaker 500557 400 block in an effort to reduce weight, another issue of the 481988 block was made for the W72 *** later (77-79?).

Yep over look the casting number Idrive.

500Hp is possible with edelbrock heads and a roller cam right intake and proper size carb.  
Engine builder,self taught auto body guy.
Horsepower sells engines and torque wins races

Pontiacman8
Pontiacman8
Pontiacman8

tuffnuff tuffnuff
Moderator | Posts: 2567 | Joined: 12/09
Posted: 03/28/11
06:12 AM

Still pricy, no matter how you slice it.,. but definitely NO way that 6X's are going to even get close to 500 horse and still be streetable.

IMO  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

Pontiacman8 Pontiacman8
Moderator | Posts: 5779 | Joined: 02/08
Posted: 03/28/11
06:22 AM

Here is a 444HP build on a 400.


ON THE DYNOAll testing was performed on a DTS PM15 dyno at Eddings Engine Rebuilding. Ambient temperature was 85 degrees, and Unocal 91-octane pump gas was used.


WESTSIDE PONTIAC 400 ENGINE
Corrected RPM Corrected Torque Horsepower
3,000 476 272
3,100 483 285.00
3,200 486 296.20
3,300 484 303.8
3,400 485 314.1
3,500 488 325.1
3,600 490 336.1
3,700 492 346.6
3,800 490.6 355
3,900 487.2 361.7
4,000 485.4 369.7
4,100 483.8 377.7
4,200 483.6 386.7
4,300 483.8 396.1
4,400 481.7 403.5
4,500 478.3 409.8
4,600 470.7 412.3
4,700 466.3 417.3
4,800 465.5 425.5
4,900 462.3 431.3
5,000 460.1 438.1
5,100 456 442.8
5,200 449.1 444.7
5,300 438.7 442.7
5,400 425.5 437.5
5,500 413 432.5

Engine Specs
Engine Displacement: 412.46ci
Horsepower: 444
Torque: 492
Bore/Stroke: 4.185x3.75-inch
Block/Crank Combo: '69 Pontiac 400 block, modified; stock-cast 400 crank modified
Bore/Stroke Ratio: 1.11:1
Rod/Stroke Ratio: 1.81:1

Bottom End
Block: '69 GTO 400 casting
Prep: Cylinders bored 0.005-inch over previous 0.060-inch overbore to 4.185-inch; deck resurfaced (0.010-inch), align-hone checked and found to be in spec
Deck Height: Block decked 0.010-inch; new pistons designed for zero-deck condition
Crank: Stock Pontiac 400, '69
Prep: Rod journals machined to 2.20-inch with BBC-style radius, mains cut 0.010 under
Balancer, Brand: Pioneer standard replacement
Type: Stock elastomer
Rods: SCAT forged-steel H-beam for BBC
Rod Length: 6.800-inch
Prep: None; check bolt stretch and side clearance
Bearings: Clevite 77, stock replacement BBC for rods; stock Pontiac 400 0.010-under for mains
Prep: Main-bearing oil holes enlarged to match block oil holes
Pistons: Ross custom-forged flat-top with valve reliefs
Prep: Check and install to connecting rods with Spirolox
Piston-to-Deck Height: Zero
Piston Pins: Ross spec'd for BBC with full-floating pins
Rings: Akerley & Childs single-moly; 1/16, 1/16, 3/16
Preparation: Set endgap to 0.020-inch, top ring; 0.022-inch, second ring
Rod Bolts or Studs: ARP cap screws spec'd by SCAT
Head Bolts or Studs: ARP head-bolt kit spec'd by Edelbrock

Oiling System
Windage Tray: Stock Pontiac full-length
Crank Scraper: None
Oil Pan: Stock '69 GTO
Oil Pump: Melling high-volume mechanical
Prep: Disassemble and deburr; weld pickup

Heads
Type, Brand: Aluminum Edelbrock Performer RPM
Chambers: Closed 72cc
Head Mods: None, out-of-box stock
Compression Ratio: 10.65:1
Valves: As supplied by Edelbrock, stainless steel
Intake Size: 2.11-inch
Exhaust Size: 1.66-inch
Angles Used in Valve Job: As performed by Edelbrock
Mods: None
Valve Guides: Edelbrock, manganese bronze
Valve Seals: Edelbrock Viton 11/32-inch
Valvesprings: Edelbrock
Rocker Studs: 7/16-inch studs, ARP
Rocker Arms: Harland Sharp aluminum adjustable full-roller
Rocker-Arm Ratio: 1.50:1
Pushrods: Smith Brothers, 5/16-inch

Cam
Brand: Engle flat-tappet hydraulic
Duration at 0.050: 236/236-deg
Lift: 0.494/0.494-inch
Centerline: 112-deg
Lobe Separation Angle: 112-deg
Installed Position: Straight up
Lifters: Engle hydraulic

Induction
Carburetor: Holley HP Series
Flow Rating: 750-cfm
Jets: Primary, #70 with 32 air bleed; secondary, #74 with 32 air bleed
Power Valve: 65
Fuel Pump: Carter mechanical, 120-gph, free-flow, 6-psi
Fuel-Line Size: 3/8-inch
Intake Manifold: Edelbrock Performer RPM, dual-plane
Mods: None

Ignition
Distributor: MSD Pro-Billet
Amplifier: MSD 6AL (7AL-2 for dyno test)
Coil: MSD
Wires: MSD 8.5mm
Total Timing: 38-deg
Initial Advance: 17 degrees BTDC
Mechanical Advance: 21 degrees
Vacuum Advance: None

Exhaust
Headers: Doug's Headers full-length four-tube
Primary Tube Diameter: 1.75-inch
Primary Tube Length: 34-inch
Collector Size: 3.5-inch

Gaskets
Brand: SCE for round-port Pontiac

I think he would be better off getting the aftermarket 455 crank with 3 inch mains and then the 500HP mark would be easier achieved.  
Engine builder,self taught auto body guy.
Horsepower sells engines and torque wins races

Pontiacman8
Pontiacman8
Pontiacman8

Pontiacman8 Pontiacman8
Moderator | Posts: 5779 | Joined: 02/08
Posted: 03/28/11
06:38 AM

Here is a 455 build.


Engine Buildup Worksheet
Engine Displacement 463ci
Bore/Stroke 4.185-in bore, 4.210-in stroke
Bottom End
Block Description '73 455
Deck Height 10.215-in
Crank '70-'73 Pontiac nodular-iron
Balancer BHJ PO-IB7-S
Rods Crower Sportsman forged steel, 6.625-in
Bearings Sealed Power HD
Pistons JE/SRP forged, flat-top with valve reliefs
Piston to Deck Height -0.005-in
Piston Pins JE full-floating with double spiral locks
Rings Total Seal TS1 gapless, low-tension oil rings (14-lb pull)
Fasteners Crower connecting rod bolts, ARP head bolts
Balancing By Hoffman Machine

With the Torker II manifold,...
    read full caption
Oiling System
Windage Tray Pontiac 455
Oil Pan Moroso 8-qt
Oil Pump Melling M54D, Moroso pickup
Heads
Casting Number 6X
Chamber Open/Closed Open
Head Mods Ported
Combustion Chamber Volume 90cc
Maximum Flow at 28 Inches of Pressure 255/179 cfm at 0.550 in
Compression Ratio 9.6:1
Valves Ferrea SS, 2.11/1.66-in
Angles Used in Valve Job 30- to 65-deg int, 45-deg exh
Retainers Comp Cams titanium
Keepers Crower jumbo locks, 10-deg with lash caps
Valve Guides K-Line liners
Valve Seals Corteco all-Teflon
Rocker Studs ARP Pro Series 2-in
Rocker Arms Crower full roller, 1.65 int/1.5:1 exh
Pushrods Smith Brothers seamless chromoly 0.083x5/16x9.150-in


Cam
Brand Crane solid roller
Duration at 0.050 252/256-deg
Lift 0.598/0.560 gross, 0.578/0.540 net
Lobe Separation Angle 112-deg
Installed Position Degreed to cam card by retarding 4 deg
Lifters Brand Crower roller
Valvesprings Comp Cams dual with damper
Seat Pressure 165 psi
Open Pressure 425 psi
Timing Chain Rollmaster -0.002-in, double-roller prestreched

The big heavy LeMans nose...
    read full caption
Induction
Dyno Carb Holley 850 4781
Dyno Jets No. 83/80
Mods Notched rear float, jet extensions
Intake Manifold Torker II single-plane
Mods Port-matched only
Ignition
Distributor MSD Pro-Billet
Amplifier MSD 6AL
Coil MSD Blaster 2
Wires MSD
Total Timing 36-deg

Screaming toward the top end...
    read full caption
Exhaust
Dyno Headers Hooker 1.75-in primaries, 3-in collectors
At The Strip
Once the engine was bolted back in the LeMans, Bill returned to the track. Though the Pontiac was quick at Atco Raceway where we photographed it, the best pass came at Bill's home track--Old Bridge Township Raceway Park in Englishtown, New Jersey. Footbraking to between 1,500 and 2,000 rpm, Bill matted the gas pedal on the last yellow. The 1-2 and 2-3 shifts were made at 6,000, and at the traps the clock showed 11.78 at 113.15. This was a substantial performance improvement.

Before And After Drag Test Results
Best Old Combo New Combo Improvement
60-ft 1.70 1.62 .08
¼-mile 12.54 11.78 .76
Best trap speed 107 113.15 5.15
Engine Changes From The Old Combo To The New
For review, the original 12.54 e.t. combo ran a Demon 850 carb on a JTES-modified Holley Dominator intake manifold, and head flow was 230 cfm.

The new combo runs a Holley 850 DP carb; a Torker II intake with a port match; a Wilson 1-inch carb spacer; the flow of 6X heads has been increased to 255 cfm; the pistons were thermal-barrier-coated by Swain Technology; and the block was partially filled with Rokblock. The same cam was retained but was retarded 4 degrees using an offset cam key.

Ancillary Engine Components
Air Cleaner K&N
Carburetor 850 DP set up like dyno carb
Jets No. 82/84 at track
Spacer Wilson 1-in aluminum tapered
Fuel Pump Mallory 140
Lines -10 from tank with sump, -8 to reg, -6 to carb
Regulator Mallory set at 7 psi
Headers Hooker 1.75-in primaries, 3-in collectors
Exhaust Kooks 3-in x-type pipe, Spintech mufflers
Timing 36-deg





Jim Taylor Holley 850 DP, No. 83/80 jets, 36 deg timing, 1-inch Wilson spacer
RPM Corr. HP Corr. Torque
4,000 395.4 516.6
4,100 402.4 515.1
4,200 410.5 512.6
4,300 420.3 512.4
4,400 429.4 511.9
4,500 441.5 512.5
4,600 449.2 512.5
4,700 459.0 510.7
4,800 468.3 510.5
4,900 473.5 505.8
5,000 479.1 501.2
5,100 485.0 497.4
5,200 490.1 492.6
5,300 492.7 485.6
5,400 494.7 478.8
5,500 496.8 472.0
5,600 497.0 464.4
5,700 498.5 457.7
5,800 500.3 451.8
5,900 496.5 441.5
6,000 493.6 430.4  
Engine builder,self taught auto body guy.
Horsepower sells engines and torque wins races

Pontiacman8
Pontiacman8
Pontiacman8

Pontiacman8 Pontiacman8
Moderator | Posts: 5779 | Joined: 02/08
Posted: 03/28/11
06:44 AM

Icon Quotetuffnuff:
Still pricy, no matter how you slice it.,. but definitely NO way that 6X's are going to even get close to 500 horse and still be streetable.

IMO


Tuff it will be pricey  that is a fact.

Street able not so much but more street able in a 455 ci. form.  
Engine builder,self taught auto body guy.
Horsepower sells engines and torque wins races

Pontiacman8
Pontiacman8
Pontiacman8

stillwell stillwell
Guru | Posts: 1335 | Joined: 01/09
Posted: 03/28/11
06:50 AM

Man thats why i love a poncho look at the trq and hp at those low rpm's!!!!just awsome.with all my susp work paid off.in low 1 give it a few revs and then just mash it i can feel the plant of the tires as they look for grip for 3 ft!!at 20 mph! Wink Keep up the great work guys I'll be following this reciepe with my next biuld.73-74 455.My local shop steve sabotta said he will dig up these 400 ,30 over forged flat tops he has.this week i'll go snag them up for my collection.will they fit a 455?i think so only the stroke is diff? Grin rain in on me knights let me know.he has 70-75 400's a few still in cars.ill take some pics today but post them late tonite so watch for them guys. Wink  
REAL CARS FUEL FROM THE BACK!

Pontiacman8 Pontiacman8
Moderator | Posts: 5779 | Joined: 02/08
Posted: 03/28/11
07:36 AM

No still 400 pistons will not work on the 455 due to the difference in stroke.  
Engine builder,self taught auto body guy.
Horsepower sells engines and torque wins races

Pontiacman8
Pontiacman8
Pontiacman8

tuffnuff tuffnuff
Moderator | Posts: 2567 | Joined: 12/09
Posted: 03/28/11
09:52 AM

The 400 pistons have a different compression height, the wrist pin is too low and with the 455 stroke, the piston would stick out above the deck at TDC.

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

69GTOby 69GTOby
Guru | Posts: 1118 | Joined: 02/09
Posted: 03/29/11
07:25 AM

Pman, the 400 build you posted uses the 72cc E heads, and indicates "Compression Ratio: 10.65:1" but uses 91 octane.  ??  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

tuffnuff tuffnuff
Moderator | Posts: 2567 | Joined: 12/09
Posted: 03/29/11
07:34 AM

Aluminum let's you get away with 1 point higher compression, because the alloy dissipates heat faster/better.

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

Pontiacman8 Pontiacman8
Moderator | Posts: 5779 | Joined: 02/08
Posted: 03/29/11
08:51 AM

Icon Quote69GTOby:
Pman, the 400 build you posted uses the 72cc E heads, and indicates "Compression Ratio: 10.65:1" but uses 91 octane.  ??

Yep, aluminum heads have a higher tolerance to detonation 11.5:1 CR is fine on 93 octane and aluminum heads.  
Engine builder,self taught auto body guy.
Horsepower sells engines and torque wins races

Pontiacman8
Pontiacman8
Pontiacman8

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