305 Vortec Heads????
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Supreme Member
Joined: Dec 2005
Posts: 1,244
Likes: 1
From: Texas City, Texas Area
Car: 89 RS, 92 Z28
Engine: 305 TBI, 350 TPI
Transmission: 700R4 Both Cars
Axle/Gears: 3.23 Posi.. 4 wheel disc both cars
305 Vortec Heads????
Anyone running a 305 with 1997 or later 305 Vortec Truck heads?? Are they any good?? Will they perform better than the stock 1989 TBI Heads??? I have a chance to get a pair for 75 dollars this weekend..I know the 350 Vortecs flow well, and have good combustion chambers, bit I have not heard anything much about the 305 versions....Thanks, Tom
On Probation
Joined: Oct 2008
Posts: 6,319
Likes: 19
From: Northern Utah
Car: seeking '90.5-'92 'bird hardtop
Engine: several
Transmission: none
Axle/Gears: none
Re: 305 Vortec Heads????
You must be careful, some of those '96-up Vortec 305 heads are still swirl-port, just like what you have. They require the Vortec intake manifolds, but they're swirl port. I've had them in my hands, I know this for fact. If you can get an intake valve loose to be sure they're not swirl-port, and if there's no crack in the exact center of either deck surface, then it's okay to buy them. But be aware that these heads don't have the same wonderful short turn as the Vortec 350 heads. They flow the exact same as the heads used with the dual-cat, 5-speed TPI F-cars. But these require the Vortec intake. I've also had these Vortec 305 heads in my little pink paws.
Thread Starter
Supreme Member
Joined: Dec 2005
Posts: 1,244
Likes: 1
From: Texas City, Texas Area
Car: 89 RS, 92 Z28
Engine: 305 TBI, 350 TPI
Transmission: 700R4 Both Cars
Axle/Gears: 3.23 Posi.. 4 wheel disc both cars
Re: 305 Vortec Heads????
Hey Attila thanks for the "heads" up.....This may sound dumb, but how do you tell by looking if they are swirl port, or not?? I will take a valve compressor with me so I can pop a vale loose...You do not happen to know what the casting numbers are for the good Vortecs do you??? once again, Thanks for the info.So you say the TPI heads are better huh???.Maybe I will just live with these heads..Tom
On Probation
Joined: Oct 2008
Posts: 6,319
Likes: 19
From: Northern Utah
Car: seeking '90.5-'92 'bird hardtop
Engine: several
Transmission: none
Axle/Gears: none
Re: 305 Vortec Heads????
Gallileo, if your car has the original LO3, then it has the swirl-ports, which are not performance heads. Also, it'll be really obvious if they're swirl port. 99.9% of newbs can tell the difference correctly, even with no instruction from experts. It's that obvious.
Grumbles or whomever, the '87-up non-swirl heads are better than 416s.
Grumbles or whomever, the '87-up non-swirl heads are better than 416s.
Member
Joined: Aug 2009
Posts: 332
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From: AZ
Car: 1978 Chevrolet impala
Engine: 350ci 300hp/356tq pace crate
Transmission: 700r4
Axle/Gears: 3.42 Yukon posi
Re: 305 Vortec Heads????
I don't doubt it, however I wont be spending any more money on this 305 unless it's upkeep or leak chasing.
Gotta pay down my enormous mountain of debt and save for that 350!
Gotta pay down my enormous mountain of debt and save for that 350!
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Joined: Jun 2006
Posts: 2,199
Likes: 1
From: West-Central
Car: 91 Trans am
Engine: built 360 TBI
Transmission: built 700r4
Axle/Gears: 10bolt/3.23
Re: 305 Vortec Heads????
Not sure anymore what cam he used, probably the LT4 production.
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Thread Starter
Supreme Member
Joined: Dec 2005
Posts: 1,244
Likes: 1
From: Texas City, Texas Area
Car: 89 RS, 92 Z28
Engine: 305 TBI, 350 TPI
Transmission: 700R4 Both Cars
Axle/Gears: 3.23 Posi.. 4 wheel disc both cars
Re: 305 Vortec Heads????
Thanks for all the input guys...I have messed with a few 350's, but this is the first trip into the 305 even tho I have had the car for years....Once again, Thanks to all....Tom
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