bbo combo???

Crankit · 01-13-2007, 06:15 PM

hi guys-pretty busy in here since I last read the post...good to see alot of questions and answers...I been putting my combo together and just wanted to get some feedback (good and bad)74 block 455 getting bored to 060..mallory dual point dist...offy 360 manifold... g heads I think...w/porting??cam undecided...any comments would be appreciated...would like to stay with a roch carb but havent found a decent one yet...have a holley and a carter afb...kinda old though...still work but I like the quadrabog....thanks crankit

70Wcars · 01-23-2007, 12:19 PM

Let us know what you want out of the engine and what it will be used in..ie. street, street/strip, full race...Cutlass, 98, year, and weight? See...lots of options and they would all have bearing on your combo espec. cam and intake/exhaust choice. Like the intake choice, I built a 455 for a guy last year in a '69 'vert, and he is using that with a Q-jet..very happy with throttle response and is now shopping for more gear!!! Good luck, happy to help.

Dan S.

70 442 W-30 4-speed
70 442 W-30 post coupe Bracket Race car...11.52 @3650 lbs.

duckblaster67 · 01-23-2007, 10:23 PM

Why .060 over? Does it need it, or can you just go .030? I would bore as little as possible just in case there's a future rebuild and you will be able to bore again if needed instead of looking for a new block!

Oldsguy · 01-24-2007, 03:08 AM

duck has a point but if you already did it no need to cry over spilt milk. Remember if you exceed .500 lift on your cam specs you need to switch to roller rockers, at least roller tip rockers. Your choice for intake sounds similar to mine.

Crankit · 01-24-2007, 05:33 PM

hi guys-thanks for the info...the 60 0ver is done recomended by the machine shop...due to motor sitting for years...nice clean cy now...the motor is going in a 72 convert for street use and an occasoinal honda thrashing

just to show them the old stuff still rules...and if that dont work then a blower is in order...I would like to get close to 400hp and want allot of 1/4 mile diggin....not much hiway...could go the nitrous route but thats cheatin...in my goffy book of rules....Iwas gonna go rochester but started looking at some holleys...I think the cam and lifters will be roller stlye ...not sure yet....any more thought just throw em out their...once again thanks guys....crank.it

70Wcars · 01-25-2007, 11:13 AM

You can get well in excess of 400 horses from a single 4-bbl hydraulic cammed 455 , but the comp. ratio would be best at above 9.25 -1...that would negate a future move to a form of forced induction. Q-jet will give you best fuel economy as well as throttle response and these carbs are on many cars running deep into the 10's. Save the money you would spend on Roller cam/ lifter set-up and spend that on a well worked Trans. and torque converter and carefully planned suspension. Just my .02.

texasred · 01-25-2007, 12:41 PM

Why a dual points distrib? My experience is they are double the headaches. HEI is the way to go. Recurve it, install Delco or Standard internals (forget about that "high output" stuff) and add an external coil...it's hot and bulletproof!

IMHO.

Oh..and what Dan and Dan said, too.

C.J.

Crankit · 01-25-2007, 05:09 PM

the reason for the dual point are they were free

cause the guy had twice the headaches

definetly hei is in the works...Iam still looking for the qjet but the holley looked nice and shiny...so stay hydraulic w/Qjet and i should be good to tear the trans and rear right out of it......oooohhhhyeah ....thanks for the imput guys gotta go do somemore shopping for parts...crankit

01-13-2007, 06:15 PM	#1 (permalink)
Crankit Junior Member Join Date: Sep 2003 Posts: 7	bbo combo??? hi guys-pretty busy in here since I last read the post...good to see alot of questions and answers...I been putting my combo together and just wanted to get some feedback (good and bad)74 block 455 getting bored to 060..mallory dual point dist...offy 360 manifold... g heads I think...w/porting??cam undecided...any comments would be appreciated...would like to stay with a roch carb but havent found a decent one yet...have a holley and a carter afb...kinda old though...still work but I like the quadrabog....thanks crankit

01-24-2007, 03:08 AM	#4 (permalink)
Oldsguy Administrator Join Date: May 2004 Location: Lees Summit MO Posts: 2,859	duck has a point but if you already did it no need to cry over spilt milk. Remember if you exceed .500 lift on your cam specs you need to switch to roller rockers, at least roller tip rockers. Your choice for intake sounds similar to mine. __________________ Dan '46 2 door

01-25-2007, 11:13 AM	#6 (permalink)
70Wcars Member Join Date: Jan 2007 Location: Texas Posts: 55	You can get well in excess of 400 horses from a single 4-bbl hydraulic cammed 455 , but the comp. ratio would be best at above 9.25 -1...that would negate a future move to a form of forced induction. Q-jet will give you best fuel economy as well as throttle response and these carbs are on many cars running deep into the 10's. Save the money you would spend on Roller cam/ lifter set-up and spend that on a well worked Trans. and torque converter and carefully planned suspension. Just my .02. __________________ Dan S 70 442 W-30 4-speed 70 442 W-30 Post Coupe Bracket Race car..11.43 @ 3650lbs.

01-25-2007, 12:41 PM	#7 (permalink)
texasred Super Moderator Join Date: Apr 2004 Location: San Antonio, Texas Posts: 806	Why a dual points distrib? My experience is they are double the headaches. HEI is the way to go. Recurve it, install Delco or Standard internals (forget about that "high output" stuff) and add an external coil...it's hot and bulletproof! IMHO. Oh..and what Dan and Dan said, too. C.J. __________________ Home of the 1971 Cutlass Supreme convertible Super Karate Monkey Death Car.

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01-23-2007, 12:19 PM	#2 (permalink)
70Wcars Member Join Date: Jan 2007 Location: Texas Posts: 55	Let us know what you want out of the engine and what it will be used in..ie. street, street/strip, full race...Cutlass, 98, year, and weight? See...lots of options and they would all have bearing on your combo espec. cam and intake/exhaust choice. Like the intake choice, I built a 455 for a guy last year in a '69 'vert, and he is using that with a Q-jet..very happy with throttle response and is now shopping for more gear!!! Good luck, happy to help. Dan S. 70 442 W-30 4-speed 70 442 W-30 post coupe Bracket Race car...11.52 @3650 lbs.

01-23-2007, 10:23 PM	#3 (permalink)
duckblaster67 Junior Member Join Date: Jan 2007 Location: South Dakota Posts: 23	Why .060 over? Does it need it, or can you just go .030? I would bore as little as possible just in case there's a future rebuild and you will be able to bore again if needed instead of looking for a new block!

01-24-2007, 05:33 PM	#5 (permalink)
Crankit Junior Member Join Date: Sep 2003 Posts: 7	hi guys-thanks for the info...the 60 0ver is done recomended by the machine shop...due to motor sitting for years...nice clean cy now...the motor is going in a 72 convert for street use and an occasoinal honda thrashing just to show them the old stuff still rules...and if that dont work then a blower is in order...I would like to get close to 400hp and want allot of 1/4 mile diggin....not much hiway...could go the nitrous route but thats cheatin...in my goffy book of rules....Iwas gonna go rochester but started looking at some holleys...I think the cam and lifters will be roller stlye ...not sure yet....any more thought just throw em out their...once again thanks guys....crank.it

01-25-2007, 05:09 PM	#8 (permalink)
Crankit Junior Member Join Date: Sep 2003 Posts: 7	the reason for the dual point are they were free cause the guy had twice the headaches definetly hei is in the works...Iam still looking for the qjet but the holley looked nice and shiny...so stay hydraulic w/Qjet and i should be good to tear the trans and rear right out of it......oooohhhhyeah ....thanks for the imput guys gotta go do somemore shopping for parts...crankit