Yellow Bullet Forums banner

Ever built a 427 BBC?

57K views 161 replies 59 participants last post by  rpf65 
#1 ·
Just curious to know what some of your experiences have been with 427's. I'm really not planning to build one any time soon, but I wouldn't totally rule it out. I'm curious to know how common steel cranks were in them, how much power said crank would take, what kind of RPM potential do they have, what cylinder head would be best for a relatively high RPM application, etc.... The only way I would build one is to put a 300 to 320 or so CC head on one, spray it, and twist the hell out of it. Has anyone tired this, and what was the outcome? I appreciate all input on this inquiry. Thanks!
 
#48 ·
I guess you know everything, and everyone else know nothing! Funny, I never mention what parts are in it and you know.

I was just on Draglist.com and it shows the owner at the time, and it ran 7.0761 @ 194.8?

'94 Chevrolet Beretta by an Unknown chassis builder | Powered by a Unknown cubic inch Pontiac with 3 speed manual transmission 1/4 Mile ET: Unknown at Unknown | 1/4 Mile MPH: Unknown at Unknown 1/8 Mile ET: Unknown at Unknown | 1/8 Mile MPH: Unknown at Unknown 1000 FT. ET: Unknown at Unknown | 1000 FT. MPH: Unknown at Unknown For PM-OUTLAW in 2001 the Avg ET is 7.0761, Avg MPH is 194.800. This entry: ET is 0.00000000 times Avg; MPH is 0.00000000 times Avg Entry's 2001 PM-OUTLAW Performance (0 to 100): ET Rating is 403.70, MPH Rating is -192.42

Whatever, I know what it makes and that all I care about. I really don't care if you like it or not
 
#50 ·
Cam core is 55mm and int. valve 2.49.

The above was ran N/A. Just like in '99 when it ran 6.98 N/A. The P/S car was trying to run P/M and they tired Nitrous to get it faster. But it does add up doesn't it?
 
#52 ·
Cam core is 55mm and int. valve 2.49.

The above was ran N/A. Just like in '99 when it ran 6.98 N/A. The P/S car was trying to run P/M and they tired Nitrous to get it faster. But it does add up doesn't it?
Like I said you don't have the valve area or the total lift req'd to be able to make 1278 from 500ci you'll never reach the peak horsepower r.p.m req'd to make that power.
 
#51 ·
Ron and AlteredBob, if you plug in the "current" NHRA MPH numbers into one of those calculators, 207 and 2350, you get 1626! And we know they don't make that much power either.

I'm just responding with what I know from MY set-up. It was built and ran by the same shop I deal with. And even ran against it in P/S by my friends, and they even remember it.

Next your going to say the "427" pump gas motor CAN'T run 9.1 @ 3100 lbs N/A too.
 
#55 ·
Ron and AlteredBob, if you plug in the "current" NHRA MPH numbers into one of those calculators, 207 and 2350, you get 1626! And we know they don't make that much power either.

I'm just responding with what I know from MY set-up. It was built and ran by the same shop I deal with. And even ran against it in P/S by my friends, and they even remember it.

Next your going to say the "427" pump gas motor CAN'T run 9.1 @ 3100 lbs N/A too.
yup!
 
#57 ·
Ron, no problem. I was just giving what I know! If they want to believe it or not. I never said the 214 was N/A, it was on 1 hit as a test. The car did go consistent 194 Mph N/A, and got into the 6's like that as well. So it's a good 900Hp piece, not directed at Ron!

I've seen the dyno sheets, and "on-track" performance, so I know about what I got, and where I stand.

Unlimited, Mr. Biggley, you the YB wizard and the best of EVERYTHING at EVERYTHING. Next your going to tell me the "other" 499 can't make 1375 either???

Whatever, have a nice life!:peeing
 
#64 ·
Here is mine:

433" BBC
Iron square port heads, CC, stainless valves
roller cam: 296in/308ex, .688 lift on both 108 LC
13.5-1 Arias pistons
stock rods w/ good bolts
Steel crank
4 bolt block
Victor Jr intake
1150 Dom
Aeromotive a1000 pump,
Glide w/5300 stall
4.88s
3300lb '66 Chevelle

10.80s @ 122

Dropping the gear to 4.33s and putting a little spray on it this year.

Good 'ole 70s technology!
 
#66 ·
Sorry it got off topic, so back to "427" as we have a few. My streetcar:

'69 Vintage 427/390Hp motor,
-432 inch GM 4 bolt block
-Gm crank and 7/16 rods, ARP bolts, ATI dampener
-TRW 13-1 piston
-'69 Closed chamber, oval heads, Ported, 2.19/1.88 SS valves
-.637/.631 265/276@.050 SOLID cam, 108CL.
-Holley Strip Dom. Intake with
-"box stock" Holley 950 Hp carb
-4800 stall and 4.10 gear
-3500+ lbs and DOT tire

Best of 10.7 N/A and 9.45 on a 200 hit.
 
#67 ·
Sorry it got off topic, so back to "427" as we have a few. My streetcar:

'69 Vintage 427/390Hp motor,
-432 inch GM 4 bolt block
-Gm crank and 7/16 rods, ARP bolts, ATI dampener
-TRW 13-1 piston
-'69 Closed chamber, oval heads, Ported, 2.19/1.88 SS valves
-.637/.631 265/276@.050 SOLID cam, 108CL.
-Holley Strip Dom. Intake with
-"box stock" Holley 950 Hp carb
-4800 stall and 4.10 gear
-3500+ lbs and DOT tire

Best of 10.7 N/A and 9.45 on a 200 hit.
Even though I realy dislike these small bore 427's, thats not bad at all. Especially when ive seen heavier modded 427's run big cam and heads with 300+ spray only to run two to three tenths slower.

I still can't bring myself to spend anymore money on mine, she just might be a engine stand queen from here on in.
I should have built a 400sb would be faster by a mile. I still dont know anyone who actualy went fast other than chuck samuels in his 86 camaro back in the NMCA days to the tune of 8.50's.
 
#68 ·
Jester, not sure if it counts, but the "pumpgasser" big bore 427 has been 8.38 with a 200 plate and 250 fogger.

Unfortunately after 5 years, a rod went on vacation last year. The motor was uppe'd om compression to 12-1's and it went 9.0 N/A at 3100. It might be back in the car this year to try and go 8.90's index (must run 8.75 in the heat) N/A before it's over with.

Now before anyone say that a "pumpgas" 427 CAN'T run bottom 9's at 3100-3150, this was a car from the "World Street Race" in LA 4 years ago. It HAS to run on 94 Octane pump piss.
 
#70 ·
Jester, not sure if it counts, but the "pumpgasser" big bore 427 has been 8.38 with a 200 plate and 250 fogger.

Unfortunately after 5 years, a rod went on vacation last year. The motor was uppe'd om compression to 12-1's and it went 9.0 N/A at 3100. It might be back in the car this year to try and go 8.90's index (must run 8.75 in the heat) N/A before it's over with.

Now before anyone say that a "pumpgas" 427 CAN'T run bottom 9's at 3100-3150, this was a car from the "World Street Race" in LA 4 years ago. It HAS to run on 94 Octane pump piss.
Hmmm, rod out the side last year... you talking about Rich's Nova?
 
#69 ·
OK boys Trash our 427

OK boys Trash ours:

1968 427 BBC machined by S&S Speed of Kingston Pa
440 cu. in. 4.250" +.060 bore x 3.76" stroke, 4 bolt main block bought in 1978 for 50 bucks
GM forged crankshaft #3967811
ATI damper
Crower sportsman rods SP93410B
Wisco pistons K109A6 10.5 to1 C.R.
Moroso 21047 oil pan
GM Signature Series #12363392 aluminum oval port heads
INT 319CFM @ .700 EXH 227CFM @ .700
Manley race master HD 11/32 ss valves. 2.19 intake 1.88 exhaust
Comp springs #930 #153 seat #383 open
Comp tool steel retainers
Comp Cams Pro Magnum roller rockers #1320
Comp stud girdle
CV products 3/8 .080 push rods

Comp solid flat tappet #11-681-47 W/ EDM lifters
262 Int 270 Exh 108 lobe separation
.635 Int lift .637 Exh lift

Pro Systems 1000 CFM carburetor
Edelbrock Victor JR, port matched
MSD billet distributor
MSD Digital 6 Ignition w/ HVC coil
Headman Hustler headers 2" tubes
Turbo 400 5000 stall converter,9" Ford with 4.56 gears

This has gotten our 3200#s + driver 69 camaro to a best so far of:
6.57 @ 103.46 MPH in the 1/8
1.38 60' @ 2790 DA
 
#72 ·
NPS which car is your 432 in? You run it lately? I probably know you too, if your around Rich's camp along with the rest of the gang thats usually there.

From the looks of these combos the 4.25 bore seems to like small heads.
Anyone car to post more combos, maybe some heavy N20 versions...
 
#73 ·
I'm ALWAYS with Rich. My 432 is in my '69 Nova streetcar that Rich is working on so I can get it out this summer. He's working on my OSCA P/S car at this time, and were planning on firing this weekend.
 
#75 ·
.060" over 427, 990 casting heads, single plane manifold, 1050 Dominator, 13:1 pistons and a cam that had way too much overlap went 9.87 in my junk. Left at 5000rpm and shifted at 8200rpm. A cam more suited to the engine and a decent set of heads probably would have put the thing in the 9.50s.
 
#76 ·
There is another combo in the "group", just not sure of specs. Car is 3300 lbs, 30 over 427, pump gas and Merlin heads, roller cam, stripe dom. intake and 4150 carb. Has been 10.60's. Same engine in the 3100 lbs car with Spray went 8.90's.

Jester, I know 95% of the EZ guys as I run out of the "Thunderz" shop. Also, Orange Z, is that Biro's?
 
#77 ·
We did one for our el camino(3250#'s with driver) .030 over trw 13to1 slugs, gm crank(.030, .030), eagle h-beam rods, 290 oval ports 2.19,1.88's, old1050 dominator on a dart intake with adapter, I can't remember the duration on the cam but the lift was .748,.714, 4.88 gear and the car went 9.94@130
 
#84 · (Edited)
Building one at the moment, it's only 425.75ci but we'll call it a 427 :D. Last 2 engines in my car were 427's also :)

No world beater, but stout. The engine in the car before this was a blown 427.





Just have to work out how to run these without butchering them :(



The big CUBE boys think it's a bit gay, but love them 427's :cool:
 
Top