hello, I just registered and thought you guys could help me out. I've got an 1983 Trans Am with a 305 (carb) in it, i was wondering what probs I may incounter if I was to slam a 403 out of a '77 OLDs, and how hard it may be to replace the 305. I was also wondering if I'd be able to fit the 403 fine with a performance carb and use the old air cleaner(because it connects to the snorkel in the hood) without any probs? -Thanks

 

I was also wondering if the 403 would bolt fine to the 700R4 Tranny??

 

Good luck
I have been on this board for a long time and have yet to here of anyone putting an olds motor into a thirdgen. As for your tranny the answer is NO. The Olds uses a BOP tranny bolt pattern, The 700 has a chevy bolt pattern. You could swap to a BOP TH350 or 400, But you'ld lose overdrive. A th2004r has dual bolt patterns so that might be an option. I don't have any idea about that swap though. If you decide to go that route have fun, And keep us enlightened.
Later
John

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82 Firebird,355,Cam 224/234, .466/.488,TH350 Tranny,650 HolleyDP,Hooker Headers(I.E. POS) Manual steering
Best 8th et 8.62@80mph.
NEW for 01
A 408,dart iron eagle heads,street dominator intake, 750 SD,cam 229/239, .497/.520, Also a big hole in the hood.
Shooting for 12's.

[This message has been edited by spud (edited January 31, 2001).]

 

thanks, i guess I'll have to find another motor then, what would you suggest to replace the 305? I'm looking for a HP build up motor, i was also thinking about 400 out of a 2nd gen, the reason i asked about the 403 was because i had one sitting around, i guess I'll have to find another use for it.

 

Why not just build a SBC 350 or (if you can find one) a SBC 400.

Not to squash your idea, but its a heck of a lot cheaper to build a SBC 350 than any other motor and make a fair amount of power.

Even if the Olds 403 was an easy swap, the limited amount of parts and expensive price would make you think twice. You would probably spend less on the SBC 350 and have more power to boot.

And if a 350 is just too small, then scour around for a SBC 400. Externally, it looks the same and to most people (except those that know their Chevys), you could tell them that its a 305 and they wouldn't know the difference.

Only if they scoped out the freeze plugs and notice the driver's side dipstick, would they think something is amiss.

 

olds 403 is a P.O.S. If you want a big motor, then go with a 383 or a 350. Youd be suprised what a difference youll feel between a 305 and a built 350 or 383.

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91 RS W/carbed 350, Vortec heads, performer rpm, Comp cams Xtreme energy 226/230 duration and .477/.480 lift. BFG Drag radials. 3.42 posi,Corvette servoed 700r4, ****ty stock converter. Edelbrock TES, 3inch cat, flowmaster with single 2.5 inch exit.
13.24@104

 

Get a crate 350 (or 383 for that matter from GM). You can spend whatever you like for whatever horsepower you want, and don't have to go through the pain of putting it together...that's just my $0.02 (I hate building engines...)

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'83 HOmaro--doesn't run
'92 Bird--burnt to a crisp
'78 T/A 400--fast, Burt Reynold's style
'83 Buick LeSabre--the Ghetto Cruiser
'01 FORD Ranger--'cause it's damn nice
"Without evil there can be no good, so it must be good to be evil some time!"

 

That 400 Pontiac from a 2nd gen would would be an excellent engine. You would still have the problems mounting the engine to the car and transmission. The 400 pontiac is way stronger and more durable than a 400 SBC at the same powerlevel. With the cost of the swap you could build a killer 350 SBC.

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82 camaro--original steering wheel, brake/gas pedals, seats--everything else modified
82camaro

 

i was thinking of an old pontiac motor in my TA. the poncho 350-389-400-and 455s all have the same dimensions. i know a guy that has put one in an 82-or 83 (he's a real poncho freak and the one who put the idea in my head) indian adventures (they have a website something like runningchief or whatever) has a kit out soon that includes mounts and headers. and as far as tranny i believe it was mid 80s buicks that had the BOP AOD tranny. get those parts and you'll have a great custom show car that makes great power.

ps. look into old pontiacs, i did and was shocked of their potential. sure chevy has a MUCH wider selection. but a MODESTLY built 400-455 putting out 400-500 ft/tq is easy and if you look hard the parts can be had for cheap.

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89 Trans Am
jet black w/ silver flake
suncoast ram-air hood
ASAI aerowing
centerline trigons
SLP headers, flowmaster.
Viper 550esp w/ rem start
Grant GT, all Kenwood.
BMR adj.phr, lca's, lca brackets, sfc's, jamex springs, PSC front end

 

82camaro, the 400 is a good engine i agree with you. But he is talking about the 403 some firebird models were offered with both of these engines. The 403 was an under powered (180 horse) Olds engine.

 

Stick with a small block Chevy engine. You won't have to worry about any adapters, etc.

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1985 Trans Am - rough and ready -- 3" cat and primary exhaust, lowered 2", custom rust body work mild fender denting. Daily driver.
1976 Corvette Stingray - not so rough, but always ready. mild 350/th350 tranny. mostly stock till I whack the hood for the blower