Rebuild original 305 or drop in a crate 350
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Joined: Sep 2010
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Rebuild original 305 or drop in a crate 350
I have a problem, part of me says rebuild my original 305 or drop in a crate 350. I am the original owner of my 1986 Z-28 and part of me says keep it original and the other side says just drop in the 350. Thoughts and opinions would be greatly appreciated.
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iTrader: (1)
Joined: Sep 2011
Posts: 330
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From: Illinois
Car: 88 Iroc-Z Convertible
Engine: 305 TPI
Transmission: 700R4
Re: Rebuild original 305 or drop in a crate 350
350.
theres nothing particularly special about an 86 Z-28 where the value would get significantly hurt by having a better motor.
theres nothing particularly special about an 86 Z-28 where the value would get significantly hurt by having a better motor.
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Joined: Nov 2005
Posts: 428
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From: Edmonton, AB
Car: '87 Z-28
Engine: LT1-topped 400
Transmission: T56
Axle/Gears: 3.42
Re: Rebuild original 305 or drop in a crate 350
It isn't a high-value car that you'll be ruining by swapping the engine... if it's not rare (well-optioned convertible or B4C police package) or absolutely pristine, like under 2k miles and stored indoors, it won't be worth more for remaining original.
If you've got money to burn and want your car to go faster, crate 350 is a decent starting point. Your power will be fairly limited by the TPI system, so the mild cam and heads that come with most crates will be fine.
If you've got money to burn and want your car to go faster, crate 350 is a decent starting point. Your power will be fairly limited by the TPI system, so the mild cam and heads that come with most crates will be fine.
Senior Member
Joined: Feb 2005
Posts: 527
Likes: 5
From: Albany NY
Car: 84 Trans AM (sold), 87 IROC, 09 C6
Engine: Lt1 in IROC
Transmission: 5 speeds
Axle/Gears: Moser 12 bolt tru tracker 3.42
Re: Rebuild original 305 or drop in a crate 350
here's an idea.....save the original 305 in a nice dry place in case somebody someday wants an all original numbers matching car.....then you can run your car with the crate engine for now.....or if you don't really need much more hp, rebuild the 305 with a good cam, headers and maybe some good heads.....for some folks that's fast enough.....depends on your needs.....
Member
Joined: May 2010
Posts: 259
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From: Boulder Colorado
Car: 1988 GTA
Engine: 5.7 TPI w/ Bosch III's
Transmission: T56
Axle/Gears: 3.27 Borg Warner 9 bolt
Re: Rebuild original 305 or drop in a crate 350
Definitely keep your original motor...just rebuild it. Keep in mind that the TPI setup was originally intended for the 305, so the bolt-on's make a much bigger difference on a 305 than on a 350. Do a search here for some fast 305's, you may be surprised.
Hope this helps.
Hope this helps.
Joined: Dec 2005
Posts: 6,499
Likes: 31
From: Macon, GA
Car: 1992 Camaro RS
Engine: Vortec headed 355, xe262
Transmission: T56
Axle/Gears: 9-bolt 3.70
Re: Rebuild original 305 or drop in a crate 350
No sense in keeping the 305 unless you're just trying to be frugal. The TPI system will suck the top end out of any engine, but a 350 that's choked by a TPI will make power that a 305 that flows well cannot. Airflow is airflow. If the 350 requires more air it's because it's making more power.
The only good reason to keep a 305 is if it's a 1 pc RMS roller block, and that's only if you just cant find a 1 pc RMS roller 350 - but they're pretty common. Your block isnt a roller block either so I dont see any advantage in keeping it at all.
The only good reason to keep a 305 is if it's a 1 pc RMS roller block, and that's only if you just cant find a 1 pc RMS roller 350 - but they're pretty common. Your block isnt a roller block either so I dont see any advantage in keeping it at all.
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