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73-87 Chevy _ GMC Trucks => Performance => Topic started by: ChevyGuy on July 31, 2003, 07:54:00 pm

Title: heads
Post by: ChevyGuy on July 31, 2003, 07:54:00 pm

I have a .060 350 with a comp cam 280H mag cam, headers, edelbrock intake(cant remember which one) 600cfm holley. My heads are 487 which flow better than 882's and they have the big valves. My question is what would happen if i added a set of vortec heads used of course and found me a edelbrock intake for them? Like horsepower and what i need for the vortec heads. Im in college and fixin to graduate. Im fixin to have my truck repainted when i get out and i wanted to do a few things to my motor. It has about 50,000 miles and also i have a th400. I dont know what the gears are now because i broke a pinion gear in my old rearend and put a hole in the housing a year ago. I think the new gears are 3.08's or back again to 3.40's. Any suggestions will be apprieciated. Also prices will help.  

Title: Re: heads
Post by: 73K20 on August 01, 2003, 08:05:00 am

The heads can be gotten used for about 300 bucks and up to about 550 new.  You need to get stiffer valve springs and use the self aligning rockers (both are cheap). Intake will probably be around 150-200 bucks (more for vortec compatible) so that is about 800 total.  This should give you a very noticble jump in performance.  Do you run headers, if not this may be a good time to switch and really let those heads breathe well.

1973 K20 - 350/350/205

Title: heads
Post by: ChevyGuy on August 07, 2003, 02:05:00 pm

I can get the heads for about $150 used... can you modify a intake to work on the heads? Why would i need stiffer springs? I thought stock springs would handle up to .500 lift? The rockers you mean that would be on the heads? I have headers on the truck.

Title: year models
Post by: ChevyGuy on August 08, 2003, 11:41:00 am

what year models am i looking for? 88-95 or 96 and up? I forgot to ask this question. The ones i can get for probally $150 are 88-95 and i have a idea about how to use the intake i got already but will the ports match up to the heads?

Title: .
Post by: bored and stroked on August 08, 2003, 11:51:00 am

vortec heads were availible from 96-2001 on 305 and 350 engines.
You can get a pair brand new for $450. You can modify a normal intake to work, but you'll loose any power gain from switching to vortecs because of the port mis-alingment. Stock vortec heads can only handle .480" lift max. You cam has exactly that much lift. Go to a chevy dealership, tell them you want a set of valvesprings from a 93-97 LT1 camaro. About $60 for the set, stock sized springs and good to .525" lift. Also get some .050" offset locks from CRANE. A edelbrock RPM vortec intake runs $170. You can get the RPM intake, heads, rockers, and I think gaskets [maybe on the gaskets] from scroggin-dickey chevy for $700 somthing.

Title: .
Post by: bored and stroked on August 08, 2003, 11:53:00 am

Forgot to mention, vortecs on the 305 and 350 motors are different. The 305 vortecs use a smaller combustion chamber [58cc] compared to the 350 vortecs 64cc.

Title: L30 heads
Post by: 79SilveradoK30 on August 08, 2003, 09:46:00 pm

Plus, the 305 Vortec heads (L30 engine) have tiny intake ports, somehwere in the 150cc range. I'm betting that wouldn't be much better than running old #882 heads.

Title: Re: L30 heads
Post by: 73K20 on August 11, 2003, 09:55:00 am

I agree with bored and stroked.  I think that he summed it up pretty well for you and said pretty much what i was going to tell you.

1973 K20 - 350/350/205

Title: .
Post by: bored and stroked on August 11, 2003, 03:33:00 pm

The 305 vortecs have 150cc ports? I was always under the impression they had indentical 170cc intakes as the L31 heads.

Title: L30s
Post by: 79SilveradoK30 on August 11, 2003, 08:45:00 pm

Well, from what I read in Chevy High Performance they have intake ports in the 150cc range. And if they were wrong about that (it's a Bow-Tie only magazine), I'd be pretty worried about what I was reading.

Title: what about
Post by: ChevyGuy on August 11, 2003, 11:06:00 pm

What about 88-95 heads? Those are out of my price range. I have 487's on the truck right now. Im trying for something cheap I think im thinking to big. The 487's have a big chamber but have the big valves and flow better than 882's. What should i stay with or do?

Title: .
Post by: bored and stroked on August 12, 2003, 03:28:00 pm

88-95 heads flow as badly as 882's. Your either going to spend $700+ for a set of heads and intake [vortecs] or your going to spend $700+ for a set of heads [aftermarket normal intake]. Thats about your only choice. Those 487's are some of the better flowing old heads out there.

Title: thanks
Post by: ChevyGuy on August 13, 2003, 12:44:00 am

thanks for the replies i got from yall. I was just wondering a cheap way of getting a few more hp's out of the old thing.  

Title: heads
Post by: 1973 500 on December 05, 2003, 04:18:00 pm

I don't know what these guys are talking about, you can get a brand new set of vortec heads from Jegs for $256.99  

Here's the specs:  

Material: Cast Iron
Intake Runner Volume: 170cc  
Combustion Chamber Volume: 64cc
Valve Diameter: 1.94'' Int./ 1.50'' Exh.
Spark Plugs: Straight

www.jegs.com

Title: Re: heads
Post by: 73K20 on December 08, 2003, 06:00:00 am

Thats all fine and good if you have the only 4 cylinder 350 in the world.  That price is each and I'm pretty sure that on a 350 you need two .  So when you figure twice that price (for two) you get $514 before shipping.

1973 K20 - 350/465(as of 10-04-03)/205

Title: heads
Post by: 1973 500 on December 11, 2003, 12:20:00 am

Yeah, and your point is what?

Title: Re: heads
Post by: 77 K30 Crew Cab Dually on January 29, 2004, 12:57:00 pm

His point is that you quoted the price for a single head. A V-8 requires 2 heads. When you buy heads  that are sold on an each basis, you must buy 2 in order to have a complete set.  

Title: Re: heads
Post by: SUX2BU99 on February 18, 2004, 02:18:00 pm

What style of heads would a stock 86 350 out of a van have on it?

Title: .
Post by: bored and stroked on February 18, 2004, 05:20:00 pm

hahahaha he brought up this old thread with wrong info, then cops an attitude with everyone, classic.

suxtbu99- it would have 76cc smog heads like 882's.

Title: Re: .
Post by: 77 K30 Crew Cab Dually on March 26, 2004, 10:47:00 am

An 86 350 will have the 68-86 style heads. The thing that's different about an 86 engine from the 68-85 350 is the shortblock. Your shortblock is a 1pc rear main seal block. The 68-85 block has the same heads but, the 68-85 block has a 2pc rear main seal. Your block will have most of the provisions for a roller cam however, it will have a flat tappet camshaft in it. Your 86 block has a passenger side dipstick like all 80 and up small block Chevrolet engines. The 68-79 350 has a driver side dipstick. The balancing is different for your 86. With a one pc rear main crankshaft comes a counterweighted flywheel/flexplate and harmonic balancer. 85 and older blocks were internally balanced. Pay attention to that.


Respectfully,
Dave

Title: Re: .
Post by: 86 4x4 on March 27, 2004, 10:58:00 am

86 blocks also have a smaller flywheel bolt pattern.