Hi!

Show us your BBC combos and tell how you think about them! :cheers:

I need to rebuild my engine and are searching for a nice comp rate and cam combo for my rectangular .990 iron heads...

 

454ci bored to 468ci, Forged Crank, 7/16" GM Rods, Seal Power LS7 replacement pistons 12.25 compression, GM LS7 Cam, GM R-Port Heads (cleaned up) 119cc, 7/16" pushrods, Dart Intake, Holley 750 HP Carb, MSD Ignition, Hedman 2" primary headers. Comp Hi-Tech Rollers with Comp springs/retainers, etc... Acts a little soggy on the bottom end with the intake, but with the M22/4.11 gear combo, comes on like gang busters quickly, idles nicely at 950.

454ci bored .100 w/366" forged truck crank = 447ci, Manley sportsman rods, ross blower pistons 8.0 compression, Comp Supercharger roller cam, Manley chain, comp rev kit, Edlebrock R-Port Alum. Heads (out of the box), Comp Hi-Tech rockers, Weiand 6-71 blower with 2x750 Holley HP Blower Carbs, Joe Hunt Magneto/Distributor. Have only ran on a stand for break in - idled at 750 after break in.

 

I'm building a Gen V 454 H.O. +.060 over
w/ forged 10:1 pistons
stock forged crank
Chevy "Dot" rods 7/16 bolts
119cc/325cfm rec heads 2.19/1.90 valves
294 or 306 comp cam
ported and polished dual plane intake
850 DP w/ mech secondaries
Vertex Magneto dist. :D


:cheers:


[Modified by Corey 68, 12:58 PM 5/16/2002]

 

433 cubic inch 454 4-bolt. No that's not a typo. It is destroked with a 427 forged crank.
Forged std length BB rods.
Forged L71 pistons, 0.030" over.
Heavily modified iron oval port heads, ported, bowl blended, 2.30"/1.88" valves unshrouded.
Torker II low-rise single plane intake.
Barry Grant Gold Claw carb with 775 cfm sleeves.
Crane solid roller camshaft, 246/254 degree duration @ 0.05"
Chrome Hooker sidemount headers.
Custom 3" sidepipe inserts.
7-qt baffled oil pan, hand filed crank scraper, windage tray.

The rest of the combo:
Custom 32" wide 5-core radiator (no radiator support used)
Remote oil filter mount with oil cooler.
Electric fuel pump with return and fuel cooler.
Lakewood bellhousing.
Hayes billet steel flywheel.
Centerforce 11" Dual Friction clutch.
M21 Close Ratio Muncie with Hurst shift package and Mark Williams yoke.
Custom 3" Driveshaft.
Stock 3.36 gears
Fiberglass 340# rear spring and 550# front gymkhana springs
Polyurethane suspension bushings.
Bilstein high pressure gas shocks.
15"x8" Rallye wheels with BFG Comp T/A R-1 255/60ZR-15 tires (discontinued).

The jury's still out on the rear end ratio. I never had a personal problem with the 3.36, but it is kind of tall for launches. I'd kind of like to leave it 3.36 and someday get a 5-speed that'll shorten the 1-4 gears.
And when those tires wear out, guess I'll be shopping for 17" wheels.

I'm about a month away from launching this baby.


[Modified by MoMo, 2:15 PM 5/16/2002]

 

454 + .030 ARP main studs, block O-ringed
Holley 850 flowed to 920
Edelbrock RPM Air Gap intake
NOS Sportmans Fogger plumbed into Air gap (100-300) shot
Edelbrock Performer RPM heads ARP head bolts
Comp Solid Roller 242 and 248 @ 050. 646 and 653 lift
Roller rockers and stud girdle
JE forged 10.25
L-88 rods Miloden bolts
Factory steel crank
Hooker super comp coated 1 7/8
Custom three inch exhaust
Flowmaster series 40
MSD 6al with timing control mounted on counsol for the NOS
Dual Holley blue pumps

Richmond 6 spd 2.70 first gear, 3.70 rear gears.
Final ratio is 4.40
Centerforce dual friction clutch

550 front springs 360 rear fiberglass mono
Bilstein shocks
forged stub axels
solid u joints

 

69 N.O.X. RATT,
I'm Just curious, what comp cam are you running? I don't reccognize that lift and duration?
:cheers:

 

TRW 2399F forged pistons will yield a 9.5:1 C/R w/ a 119cc chamber volume. These are basically '71 LS-6 pistons.

Cams are all over the place but if you budget allows it I would go with a hydraulic roller cam with duration in the 235-245 degree at .050" range, .550"+ lift and 110 degree LSA.

 

Corey: It is a newer grind xr280r done a 110 lobe

 

Hate to say it but the Chevelle.com forum has the best BBC info around.

Here is Racer1320's formula for a street driven car. It is called a BSE (Basic Street Engine).

-454+.060 = 467
-TRW # 2399 pistons with Speed Pro file fit rings
-10.0 - 10.7 CR depending on deck height, final combustion chamber volume and head gasket used.
-Clevite bearings - mains, rod and cam
-Fel-Pro gaskets
-GM 3/8" rods with ARP bolts and GM crank(cast is fine at this level) with ARP main studs and GM windage tray
-Moroso 6-Quart kicked-out pan # 20401 with pickup # 24440
-Melling oil pump
-Manley or DynaGear double roller timing chain
-#215 closed chamber oval port heads '67 - '68 with 2.19 / 1.88 valves, gasket matched and bowls blended
-Performer RPM Q-Jet Manifold with GM lifter valley splash shield
-Q-Jet carb with 75 main jet, 45B primary rod, AX secondary rods and B hanger
-1/2" phenolic 4-hole spacer
-GM carb heat shield
-Ultradyne 288 / 296 hydraulic cam with matching springs - double w/damper. cam specs are 231I / 239E duration @ .050 with .550 / .575 lift ground on a 110LSA. Install on a 108 intake centerline
-Rockers - either crane steel long slots or a roller. Isky are the best aluminum, Crower the best Stainless steel. Neither are needed at the power level.
-3/8" one piece pushrods Crane or Comp
-MSD ignition- 6AL box, coil and distributer(optional-allows easy curve adjustment)
-Headers - 1 3/4" PRIMARY TUBE WITH 3" collectors. Remove collector(cut off) and install(weld) Flowmaster Scavenger Collectors # C-134214300
-3" headpipes with 3" crossover and 2 1/2" tailpipes. All bends to be mandrel. Use Flowmaster Big Block mufflers 3" in and out, offset - offset (quietest performance muffler) or DynoMax Oval RaceMagnum.
-Mallory Comp 140 fuel pump, regulator and filter plumbed to stock 3/8" fuel line.
-Mobil 1 10W-30 oil, Ford type F trans fluid and Mobil 1 gear lube
-indexed spark plugs
With a turbo 400, ATI 10" converter, 3.73 gears and either slicks or DOT slicks this combo will run 11.60's to 11.90's depending on weather, tuning and driver. My best was 11.49 @ 115 in mine shaft air weighing 4000+ lbs. on pump gas.
I must tell you though that with a stick you'll never hook up on the street or track. This will get fustrating real quick especially when cars having much less power are running quicker than you.

This combo is fully streetable and was regularly driven to the track some 140 miles away and 2+ hours(one way) on a weekly basis. It was driven anywhere, never over heated and got 12-13 MPG on the highway with a lite foot.

Now find a competent machine shop / engine builder that can do precision machine work and assembly in your area.

Set the total timing to 36 degrees and shift at 5800 for best ET.

For my current combo just substitute a Comp cams street roller custom ground 238I / 244E duration @ .050 with the appropriate springs, titanium retainers, roller lifters(Crower), roller rockers(Crane Gold), Performer RPM Air-Gap(not worth any ET), Holley 950 or 1000HP, 4.10 gear, lose the tailpipes and raise the shift point 200 RPM to 6000 and you'll run high 10's. Just don't forget things like a roll bar, SFI balancer, SFI bell housing shield, and a real good suspension / tire package.

Hope this helps.

Terry



[Modified by trw, 11:09 PM 5/16/2002]

 

Good set-up. That is essentially the same combo I built with my LS-5 with the exception of open chamber heads and the low gears. If you want to drive the car on the freeway forget about those 3.73's. I found that 3.55's were too low and went back to the stock 3.08's. This engine combo has enough torque to pull the taller 3.08 and they are much easier to hook up with street tires.


[Modified by RatRacer, 11:16 AM 5/17/2002]

 

See my sig, no real driving experience on this set up yet... :blueangel:

 

502 G.M. block bored 30 over.4.25 stroke crank=540 cid.10-1 J&E pistons.Scat crank.Eagle H beam rods.Edelbrck performer aluminumn heads(square port)With about $2000 worth of port work.Performer rpm intake with runner work and port matched.1050 race demon.Crane roller cam(636 lift ,310 duration.).2 1/8 inch Hooker super comps.Also has B&M tranny with 3000 stall converter.This combo will smoke the tires forever.Thats why I put in a narrowed 9 and 17 inch wide Mickey Thompsons.


[Modified by 540 vette, 9:39 PM 5/17/2002]


[Modified by 540 vette, 9:40 PM 5/17/2002]