Cylinder Head Question
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Joined: Dec 2010
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From: columbus ohio
Team Owner
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From: altered state
St. Jude Donor '05
don't understand why GM doesn't just make the same exact head, just out of aluminum, instead of cast iron. They'd sell about a gazillion of 'em.
Make em just a little bigger, better flowing too.
On tires, a sticky 15" tire will always hook better than the 17.
Tons of tires available to do this with and 15s are cheap.
Stiffer the sidewall easier they will spin.
Le Mans Master
Joined: Jun 2004
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From: Seattle WA
St. Jude Donor '14
They flow better than most Tier I heads...but they do make bigger ones. I don't think we'll see an aluminum Vortec from GMPP, but you never know. There are a lot more options in aluminum heads when we start getting into bigger budgets and flow numbers.
There are two iron Bowtie Vortec heads - the "small port" with 185cc intake runners (P/N 25534421) and the "large port" with 225cc intake runners (P/N 2553446). I haven't looked at tested flow numbers but GMPP claims 285 CFM @ .600 lift for the large port heads. I haven't worked with either of these, but I'd love to use either on a 383 build.
There are two iron Bowtie Vortec heads - the "small port" with 185cc intake runners (P/N 25534421) and the "large port" with 225cc intake runners (P/N 2553446). I haven't looked at tested flow numbers but GMPP claims 285 CFM @ .600 lift for the large port heads. I haven't worked with either of these, but I'd love to use either on a 383 build.
Le Mans Master
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From: Seattle WA
St. Jude Donor '14
I had to chuckle a bit at the center bolt valve covers being "significantly more expensive" - I get take-offs on fleabay for about $20/set at most
Burning Brakes
Joined: Jun 2009
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From: Syracuse IN
Some are just stuck in the past. We run VORTEC heads on every chevy motor upgrade at our shop. The Vortec heads have a better seal for valve cover, and a better intake manifold seal. Self alighning rockers are no problem either. If you have a head which is wooped and needs rebuilt, the original rockers are worn out also. The only real increase in cost is the intake manifold change. Al
Le Mans Master
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From: Oquirrh Mountains
St. Jude Donor '09
Some are just stuck in the past. We run VORTEC heads on every chevy motor upgrade at our shop. The Vortec heads have a better seal for valve cover, and a better intake manifold seal. Self alighning rockers are no problem either. If you have a head which is wooped and needs rebuilt, the original rockers are worn out also. The only real increase in cost is the intake manifold change. Al
It's amazing. Some of the posts you see by folks who have never used a pair, but are ex-spurts on them based upon a single article in a magazine which changed half a dozen things at a time and then claim it's this or that product that made the difference according to the advertizing sold that month.
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Le Mans Master
Joined: Jun 2004
Posts: 6,231
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From: Seattle WA
St. Jude Donor '14
We run VORTEC heads on every chevy motor upgrade at our shop. The Vortec heads have a better seal for valve cover, and a better intake manifold seal. Self alighning rockers are no problem either. If you have a head which is wooped and needs rebuilt, the original rockers are worn out also. The only real increase in cost is the intake manifold change. Al
...and if someone is doing a complete top then the intake is a wash as well.
Burning Brakes
Joined: Jun 2009
Posts: 840
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From: Syracuse IN
We keep at least one complete top end kit in stock, Heads, rockers, push rods, intake and valve covers. Oh yea, all Vortec. In the summer months I keep ZZ4 rotating assy in stock as well, winter we always have enough time to place an order. Our customers want turn key and go performance. That is what we strive to supply. I should note we are in the Marine business. Al
Race Director
Joined: Jan 2000
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From: San Jose CA
They flow better than most Tier I heads...but they do make bigger ones. I don't think we'll see an aluminum Vortec from GMPP, but you never know. There are a lot more options in aluminum heads when we start getting into bigger budgets and flow numbers.
There are two iron Bowtie Vortec heads - the "small port" with 185cc intake runners (P/N 25534421) and the "large port" with 225cc intake runners (P/N 2553446). I haven't looked at tested flow numbers but GMPP claims 285 CFM @ .600 lift for the large port heads. I haven't worked with either of these, but I'd love to use either on a 383 build.
There are two iron Bowtie Vortec heads - the "small port" with 185cc intake runners (P/N 25534421) and the "large port" with 225cc intake runners (P/N 2553446). I haven't looked at tested flow numbers but GMPP claims 285 CFM @ .600 lift for the large port heads. I haven't worked with either of these, but I'd love to use either on a 383 build.
My take on the Vortecs has been if you have big power dreams, which a lot of people seem to, that it's best to pass them by. I've heard way too many "I want 300+rwhp and here's my plan:" with Vortec heads being part of the equation and it's just not worth it. I'd rather go with a better flowing head and not have to have as wild a cam to push the power through.
However, if you're just looking for a strong runner (250-300 crank HP) and honestly know you won't have a strong taste for more (who actually knows that?) - I think they have a good solid place. Especially in a cruiser.
Le Mans Master
Joined: Jun 2004
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From: Seattle WA
St. Jude Donor '14
they have a dual bolt pattern so you can run a Vortec intake (8-bolt) or a classic 12-bolt.
"I want 300+rwhp and here's my plan:" with Vortec heads being part of the equation and it's just not worth it. I'd rather go with a better flowing head and not have to have as wild a cam to push the power through.
"I want 300+rwhp and here's my plan:" with Vortec heads being part of the equation and it's just not worth it. I'd rather go with a better flowing head and not have to have as wild a cam to push the power through.
I don't understand that concept of a needing "as wild a cam" - a head will only flow what it will flow regardless of the cam used. A Vortec 355 will absolutely make 300 RWHP (or around 1 FWHP/CID) or a small bit better with a very streetable cam (I've built a bunch)...but I agree that's as far as it's going to go. Buying more flow and then using a too-small cam leads to a "lazy" engine with poor low-speed throttle response.
Design is always around the heads; flow determines how much power the engine will make, the cam is selected to maximize the capabilities of the head and RPM range where we want the power, and the shortblock is built to support the power level.
For a lot of folks budget is a lot more of a driver than power levels. I get a lot of builds where the owner starts out wanting a 500 HP screamer...and ends up with a mild 383 making around 1 HP/CID
Over the years I've found that 1HP/CID number to be just about perfect for most street-going engines - the cost goes up geometrically after that figure and the street manners start to drop a bit.
Race Director
Joined: Jan 2000
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From: San Jose CA
(*edit* but they don't want to spend the $$ to do it the right way...)Part of the problem with my perspective is living in a (the?) smog-state, so I try to think about builds with cam timing <230*.
Many people (even here) consider a cam in the 230s to be mild.
Last edited by Shark Racer; Nov 18, 2011 at 11:57 AM.
Racer
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From: Bishop CA
Of course not - you're an engine builder. There's still a strong contingent of people who live on HP numbers and don't give a damn about average power, torque at low RPM, etc. They just want to slap down a sheet somewhere that says xxxRWHP. (*edit* but they don't want to spend the $$ to do it the right way...)
Part of the problem with my perspective is living in a (the?) smog-state, so I try to think about builds with cam timing <230*.
Many people (even here) consider a cam in the 230s to be mild.
(*edit* but they don't want to spend the $$ to do it the right way...)Part of the problem with my perspective is living in a (the?) smog-state, so I try to think about builds with cam timing <230*.
Many people (even here) consider a cam in the 230s to be mild.
Team Owner
Joined: Oct 2004
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From: altered state
St. Jude Donor '05
Of course not - you're an engine builder. There's still a strong contingent of people who live on HP numbers and don't give a damn about average power, torque at low RPM, etc. They just want to slap down a sheet somewhere that says xxxRWHP. (*edit* but they don't want to spend the $$ to do it the right way...)
As said the Vortecs are a great budget street head for decent torque.
Problem is too many give them credit for being something they are not which is a big hp builder. They just arent put together for that no matter what some mag article says
yet youll see so many convince someone they can get a big # anyways only to see the poster pissed 2 mos later that hes dissapointed in the way it runs cause someone told him to mismatch everything in quest of big power on the cheap
....and many do not flow the #s out of the box you read about those seem to get inflated too. Had a few on the bench to prove that one wrong.
Nice torque upgrade from stock/$ spent...thats about it.
But they are new, GM quality theres something to be said about that.
Last edited by cv67; Nov 18, 2011 at 11:30 PM.
Le Mans Master
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From: Seattle WA
St. Jude Donor '14
Care to post your flow numbers? I have as well and found them quite consistent. I'm lucky to have a great machine shop that only charges around $50 for one cylinder.
There seems to be a bunch of confusion here over these heads - at 1 HP/CID or thereabouts I have yet to see a better choce. Beyond that, no.
The folks that are really causing trouble are the ones selling "upgraded" heads that offer lift way beyond what the head will flow at.
There seems to be a bunch of confusion here over these heads - at 1 HP/CID or thereabouts I have yet to see a better choce. Beyond that, no.
The folks that are really causing trouble are the ones selling "upgraded" heads that offer lift way beyond what the head will flow at.
Last edited by billla; Nov 18, 2011 at 11:42 PM.
Racer
Joined: Oct 2006
Posts: 435
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From: Florida
As said the Vortecs are a great budget street head for decent torque.
Problem is too many give them credit for being something they are not which is a big hp builder. They just arent put together for that no matter what some mag article says
yet youll see so many convince someone they can get a big # anyways only to see the poster pissed 2 mos later that hes dissapointed in the way it runs cause someone told him to mismatch everything in quest of big power on the cheap
....and many do not flow the #s out of the box you read about those seem to get inflated too. Had a few on the bench to prove that one wrong.
Nice torque upgrade from stock/$ spent...thats about it.
But they are new, GM quality theres something to be said about that.
Race Director
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From: San Jose CA
Racer
Joined: Oct 2006
Posts: 435
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From: Florida
I understand the HEAD has the dual pattern. What standard pattern INTAKE has vortec ports so they don't mismatch? Meaning, so the ports don't mismatch....
Last edited by tt 383; Nov 19, 2011 at 01:33 AM.