305...interchangeable with 350?
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Junior Member
Joined: Oct 2007
Posts: 25
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From: virginia
Car: firebird
Engine: 305
Transmission: t-5
Axle/Gears: 3.23
305...interchangeable with 350?
Hi i have recently been wanting to get a 350... for my 87 firebird but my parents dont want me to have that much power. but they have agreed to let me upgrade my car because its currently it is stock, so when i finally can switch to a 350 will i be able to use the parts from my 305 on the 350?
Joined: Aug 2006
Posts: 12,803
Likes: 103
From: Central NJ
Car: 86 Trans Am
Engine: 408 stroker sbc
Transmission: TKO600
Axle/Gears: Moser full floater m9, 3:70 trutrac
Re: 305...interchangeable with 350?
there are sooooo many threads like this, a quick search will get you more info than you could ever want on this topic
but yes, the 305 is identical externally to a 350, induction may need a little tunning/upgrading, carb/TPI/TBI to match the larger engine
but yes, the 305 is identical externally to a 350, induction may need a little tunning/upgrading, carb/TPI/TBI to match the larger engine
Member
Joined: Apr 2006
Posts: 149
Likes: 2
From: Texas
Car: 91 z-28
Engine: 350 F code
Transmission: 5spd
Re: 305...interchangeable with 350?
Since your parts are basically identical externally, a good idea is to look more at what you need to replace/ modify in your injection and computer system to get it to run right after the swap.
Basically any 350 made 87 or later will will work (until you get to vortec heads, but even then you can buy a lower intake manifold that will get you back on the right track for about $300.)
Cam, headers, catback, throttle body mods, new sensors(hint hint) will all swap right onto your 350 when ever you get ready.
except your Knock sensor, which is different in a 350 than it is in a 305 i hear.
Basically any 350 made 87 or later will will work (until you get to vortec heads, but even then you can buy a lower intake manifold that will get you back on the right track for about $300.)
Cam, headers, catback, throttle body mods, new sensors(hint hint) will all swap right onto your 350 when ever you get ready.
except your Knock sensor, which is different in a 350 than it is in a 305 i hear.
Junior Member
Joined: Dec 2006
Posts: 41
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From: Lansing Illinois
Car: 86 GTA
Engine: 402 cbb
Transmission: th350
Axle/Gears: 9" 3.50
Re: 305...interchangeable with 350?
I swapped a 350 for a 305 in a Caprice and if I remember correctly the only thing that didn't bolt up right was the exhaust manifolds.
Joined: Mar 2000
Posts: 43,187
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
That would only be an issue if you had 6-bolt exhaust heads.
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