[427maliboo]

427 or 496 ?? Need help with build?? MORE HP? TORQUE?

Would a 496 be a better for me with my setup over my current 427.

I currently have a 427 setup and I broke a solid lifter and chunked out the block #8 intake.pics http://www.wyattco.com:80/427rip.htm I have been dreaming of going with a big cube motor for awhile. I tore it down and all it needs is bearings/rings and it is ready to go into a new block. I am kicking around building a 496. When I look at all the builds out there I feel like I am going to be pretty close in performance as I am with my 427. I am sure I will pick up some torque maybe 75ft+ lbs but 427 revs/winds like a monster. So heres the deal. Here are the parts and car I have and what I propose and would like some feedback on thought in performance gain. This is a for a 90% strip and 10% street car. If I go 496 I have another 4 bolt block and will get it machined/studded and use all the parts below minus the rotating assembly. If I go 496 I am thinking this http://www.cnc-motorsports.com/produ...38&CtgID=20737 Can use current flywheel/balancer with this kit.

Current setup
427 CU 4.25 bore 3.75 stroke
9.8 standard deck 4 bolt mains arp head/main studs
L2300F 12cc TRW forged pistons / moly rings 10.1 CR
396 Forged crankshaft 10/10
Stock rods resized/ARP bolts
Clevite 77 bearings
Edlebrock 454 Performer RPM heads angle milled 100cc "roval port"
Pro valve job/mild port work
Lunati Voodoo Solid Roller 60233
Advertised Duration (Int/Exh): 279/285
Duration @ .050 (Int/Exh): 249/255
Gross Valve Lift (Int/Exh): .663/.685
LSA/ICL: 110/106
Valve Lash (Int/Exh): .018/.018
RPM Range: 2800-7000

Edelbrock Victor JR 454-O plumbed with single stage fogger kit
Holley 4150 HP 1000
Hooker Super Comp 2" primary/3.5" dumps/3 inch mufflers
CSR electric water pump
Moroso 6 Quart pan/oil pump
Gazen Vacuum pump
Aeromotive A1000 pump/reg bypass system AN-10
http://www.wyattco.com/malibu/0429081146.jpg

Turbo 400 Manual valve Foot brake
3400 Stall shifting 7200rpm
Moser 9" 3.70
MT Drag radials 275/60/15 28"

91 octane corner store fuel
Best NA is 11.35 @ 118.5mph 1.65 60ft 34degrees timing 12.4 AFR
Lost cylinder #8 12.11 @ 113mph
Decided what the hell lets spray it 175 shot on 7 cylinders 10.8 AFR
10.30 130 mph 1.55 60ft

Car weighs 3600+ with me in it and is lazy out of the hole. Needs more stall or gear. Car is legal to 10.0 but would not mind going faster. Honestly about had it with the cost of nitrous and will probally be running most time NA.

I am thinking my 427 was making about 450-460hp NA to the wheels so it must be making around 525-550 hp at the flywheel. Correct me if I am wrong.

I do not have a dyno program but I am thinking a 10.5cr 496 with my above parts will make 650ish hp and 650 ftlbs. I know the 496 willl have most all of its torque 3-6k and that may be the way to go. If anyone has a dyno program(posted here and on another post) please help me out. Would be intested in an estimate of ET/MPH.


Thanks in advance for any help/suggestions.

James

[Harold Sutton]

A 496 will have lots more power than a 427. The main place you'll see the difference is when you put it in the higher gears. My 454 with nothing special ran a best of 11.15 @ 126.76 with 4.10s and a four speed and wouldn't leave at all well. (It lit the tires on the 11.15 run but was the best leave of the bunch). Out of five passes, it ran above 125 mph on all of them.

[Bob West]

Mine is a 10.5-1 505 (91-94 octane), with a bit more cam (255/263), converter (ATI flashes 5k or so), gear (4.10's) and weight (3680) too. ET in signature. I'm hoping to get a 9.99999 today at KCIR.

[blue66]

My 496 is 10.5:1, AFR 305cc heads, 267/271 cam, edge converter 4500, 4.56 gear, going back to 4.10 gear. ET's in sig.

[427maliboo]

Thanks for the info. Anyone have a recomendation for a cam with these head/496

James

[wildman926]

I run the Voodoo 60234 -
Advertised Duration (Int/Exh): 285/293
Duration @ .050 (Int/Exh): 255/263
Gross Valve Lift (Int/Exh): .680/.680
LSA/ICL: 110/106
Valve Lash (Int/Exh): .018/.018
RPM Range: 3000-7200

Here is the solid FT version of it - 402A7
Advertised Duration (Int/Exh): 288/296
Duration @ .050 (Int/Exh): 255/263
Gross Valve Lift (Int/Exh): .612/.630
LSA/ICL: 110/104
Valve Lash (Int/Exh): .024/.026
RPM Range: 3000-7000

You can here it HERE

[cstraub]

Camshaft will be determined by how much rpm you want to turn the engine. The rovals out of the box are okay but respond well to port work. I would send a PM to Crankitup as he has the 496 with the heads that you are looking at.

If you want to drop me a PM I can help figure out what is best for your goals and what combo it will take to get you there.

[Twins Fan]

Here's a DynoSim comparison for you. The 427 with your listed parts (just used the Edelbrock roval flow #'s in the program) came up with 598 HP @ 6500 and 570 TQ @ 4500. Leaving all else the same and changing it to a 496 with 10.5 to 1 CR came up with 590 HP @ 5500 and 630 TQ @ 4000 with a big bump in torque from 3000 to 5000 rpm (600+ in that range).

[427maliboo]

Thanks for the reply. Im curious with that much torque down low it would change my et. Any thoughts?

James

[TJ1967SS]

Originally Posted by 427maliboo

Thanks for the reply. Im curious with that much torque down low it would change my et. Any thoughts?

James

Might pull mega moon wheelies!

In my honest opinion... I got a boat and need a new anchor, your old broken block would fit the cliche'

bump thread to top for friend