Author Topic: 1973 455 help decoding?  (Read 956 times)

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Offline cgore611

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1973 455 help decoding?
« on: February 16, 2011, 03:52:45 PM »
I'm looking at a 1973 455 that supposedly came out of a grandville?  the casting number is 485428. It has 4X heads and numbers on front of engine is 0616448 XA.  What is the horsepower and torque of this motor? Thing of putting this in my 78 TA. Have a 75 pontiac 350 in car now. Also, it has a pontiac performer intake with an eldebrock 600 carb, can I put that intake and carb on the 455? What can I do to beef the 455 up any or will I need too? Thanks


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Re: 1973 455 help decoding?
« Reply #1 on: February 16, 2011, 04:02:13 PM »
If it is XA it is a 250 hp 1973 from an A or B body.
« Last Edit: February 16, 2011, 04:05:01 PM by LOMILETA »
1978 TA-462 ci Buick (just sold)
1980 Turbo Formula
1995 Grand Prix
2002 TA convertible

Offline cgore611

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Re: 1973 455 help decoding?
« Reply #2 on: February 16, 2011, 04:22:22 PM »
What kind of torque would it have in my TA? Good swap or not?

Offline ShakerBreaker

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Re: 1973 455 help decoding?
« Reply #3 on: February 16, 2011, 06:14:31 PM »
-check out

Offline brian c

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Re: 1973 455 help decoding?
« Reply #4 on: February 17, 2011, 03:54:26 PM »
The good news is that since you're going from a Pontiac 350 to a Pontiac 455 you can leave the cross member mounts right where they are. Also all your accessories will move over from the 350 to the 455 so no need to buy anything new.

That being said, GM put carbs on the 455 that flowed around 800cfm so that edelbrock carb of yours is going to choke the living heck out of that 455. What I'd recommend doing is sourcing a correct Quadrajet and then speak with Cliff Ruggles to get a rebuild kit that includes the goodies to get it running as it should.

Now as for beefing up the engine, the limit is your pocket book. What are you looking for performance wise out of the engine? Car? Are you looking for mostly a street car? Some track? Full on race? All these questions factor in to what parts you're going to be buying.

We can use my 455 as an example....

*1970 4 bolt main Pontiac 455 bored 60 over
*Stock crank
*Stock rods - I was on a budget and my car will not see track time
*New oversized flat top pistons
*New rings - sized for the overbore
*New bearings
*Custom ground cam - spec'd by R&R Engineering to 400hp (boo all you want, I didn't have a problem with him)
*Pontiac 6x-4 heads - hardened valve seats installed
*Comp Cams double roller timing chain
*Comp Cams 1.52 roller tip rockers
*Edelbrock Performer RPM intake manifold
*RA spec oil pump
*FlowKooler waterpump
*Pertronix Flamethrower HEI distributor
*IMI Hi-torque mini starter
*Holley 3310C carb - will be replaced with a quadrajet with the Cliff kit when I get the $$ for the kit

I'm also running a TH350 w/shift kit and 3.42:1 gearing w/posi out back. From a dead stop, I can spin my tires and the car for that matter. I've come out of a parking lot on more than one occasion, hit the gas to make a turn into traffic, and been looking at the sidewalk because the car has that much power. Sometimes I think I went a little too far on the power side of things....Nah! ;D

1978 Y88, '70 455 HO block bored 0.060, TH350, 3.42:1 gears...Oct '08 Fbodywarehouse Calendar - Woot!
1980 Firebird - no engine/tranny... to be pacecar clone