G.M. Crate engine?
Thread Starter
Instructor
Joined: Feb 2007
Posts: 112
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From: Macungie PA
G.M. Crate engine?
I just bought a 1990 and it has a Crate Engine part #12486041, the dealer told me it is the 330h.p. engine. It has allum. heads and I thought the 330h.p. came with cast heads ? How could I tell what heads it has on it?
Thanks,
Eric
Thanks,
Eric
Drifting
Joined: Sep 2004
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Carl Johansson
Le Mans Master
Joined: Jan 2002
Posts: 9,036
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From: Edmonton AB
- you will know at a glance whether your heads are the Vortecs if
there are only four vertical fasteners instead of six inclined ones
per side. Like Carl Johansson says, also use a magnet to check the
head material - unless there has been a change, you are right about
the 330HP shipping with iron heads.
From GM Parts Direct
DESCRIPTION: ENG-330HP HO BASE
Our lowest priced crate engine, the 330 horsepower 350 HO doesn't sacrifice power or durability, it just pumps up the value. With its four bolt main block, nodular iron crankshaft, powerded metal steel connecting rods and light but strong cast aluminum pistons, this engine screams durability. Add to the strong foundation a pair of 64cc Vortec cast iron cylinder heads and a dual pattern camshaft with just a bit of a "lumpy" idle, and you've got the muscle car small block that you've been looking for. Dressed to impress with chrome valve covers and timing cover, this engine will look great between the fenders of your favorite street rod, muscle car or grass roots racer. The cylinder heads on this great little performer use 1.94" intake and 1.50" exhaust valves that are sprung with 5.7 Liter L31 valve springs. The 64cc chambers yield a healthy, but streetable 9.1 to 1 compression ratio. The cam is a modern dual pattern interpretation of the old '65 to '67 Corvette 327 cam. But with more lift and duration on the exhaust side, it does a better job of clearing exhaust from the combustion chamber. We also decreased duration and lift ever so slightly on the intake side to build more cylinder pressure. The result is a cam that makes great torque and horsepower with the 350 HO's compression ratio. Add the new dual plane intake manifold P/N 12496820, 650 cfm carburetor, HEI distributor, torsional damper, water pump and exhaust manifolds or headers and you've got an outstanding muscle motor with a broad, smooth torque curve and an honest 330 horsepower. This manifold has four bolts, not six, to attach it to the cylinder head. Older six-bolt manifolds will not fit the new Vortec heads. The 350 HO is not intended for marine use, and should only be used in 1975 and earlier pre-emissions street vehicles or any year off road vehicles.
Our lowest priced crate engine, the 330 horsepower 350 HO doesn't sacrifice power or durability, it just pumps up the value. With its four bolt main block, nodular iron crankshaft, powerded metal steel connecting rods and light but strong cast aluminum pistons, this engine screams durability. Add to the strong foundation a pair of 64cc Vortec cast iron cylinder heads and a dual pattern camshaft with just a bit of a "lumpy" idle, and you've got the muscle car small block that you've been looking for. Dressed to impress with chrome valve covers and timing cover, this engine will look great between the fenders of your favorite street rod, muscle car or grass roots racer. The cylinder heads on this great little performer use 1.94" intake and 1.50" exhaust valves that are sprung with 5.7 Liter L31 valve springs. The 64cc chambers yield a healthy, but streetable 9.1 to 1 compression ratio. The cam is a modern dual pattern interpretation of the old '65 to '67 Corvette 327 cam. But with more lift and duration on the exhaust side, it does a better job of clearing exhaust from the combustion chamber. We also decreased duration and lift ever so slightly on the intake side to build more cylinder pressure. The result is a cam that makes great torque and horsepower with the 350 HO's compression ratio. Add the new dual plane intake manifold P/N 12496820, 650 cfm carburetor, HEI distributor, torsional damper, water pump and exhaust manifolds or headers and you've got an outstanding muscle motor with a broad, smooth torque curve and an honest 330 horsepower. This manifold has four bolts, not six, to attach it to the cylinder head. Older six-bolt manifolds will not fit the new Vortec heads. The 350 HO is not intended for marine use, and should only be used in 1975 and earlier pre-emissions street vehicles or any year off road vehicles.
Le Mans Master
Joined: Jan 2002
Posts: 9,036
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From: Edmonton AB
If it turns out that the heads have six bolts, are aluminum and have
center-bolt valve covers - it is possible that the original heads have
been swapped onto the engine.
Original aluminum heads for a '90 have the casting number #10088113
under the valve covers. The OEM characteristics are: angled plugs,
58cc chambers, 1.94"/1.5" valves and raised "D-shaped" exhaust ports.
What intake system is on the car - the OEM Tuned Port Injection?
.
center-bolt valve covers - it is possible that the original heads have
been swapped onto the engine.
Original aluminum heads for a '90 have the casting number #10088113
under the valve covers. The OEM characteristics are: angled plugs,
58cc chambers, 1.94"/1.5" valves and raised "D-shaped" exhaust ports.
What intake system is on the car - the OEM Tuned Port Injection?
.
Thread Starter
Instructor
Joined: Feb 2007
Posts: 112
Likes: 0
From: Macungie PA
If it turns out that the heads have six bolts, are aluminum and have
center-bolt valve covers - it is possible that the original heads have
been swapped onto the engine.
Original aluminum heads for a '90 have the casting number #10088113
under the valve covers. The OEM characteristics are: angled plugs,
58cc chambers, 1.94"/1.5" valves and raised "D-shaped" exhaust ports.
What intake system is on the car - the OEM Tuned Port Injection?
.
center-bolt valve covers - it is possible that the original heads have
been swapped onto the engine.
Original aluminum heads for a '90 have the casting number #10088113
under the valve covers. The OEM characteristics are: angled plugs,
58cc chambers, 1.94"/1.5" valves and raised "D-shaped" exhaust ports.
What intake system is on the car - the OEM Tuned Port Injection?
.
Are these heads better or worse then the ones that came with the 330hp motor?
Team Owner
Joined: Sep 2001
Posts: 62,097
Likes: 1,724
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I personally would rather have the '113s than the Vortec, but theyre pretty close to each other.
The engine doesnt make the 330hp its rated at anyway with the stock TPI intake on it, independent of head choice the TPI chokes it.
The engine doesnt make the 330hp its rated at anyway with the stock TPI intake on it, independent of head choice the TPI chokes it.
Thread Starter
Instructor
Joined: Feb 2007
Posts: 112
Likes: 0
From: Macungie PA
What would you recomend for the intake ? What else would you recomend to make more power with this engine/head setup ?
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
The '113' heads were stock for 90 and 91.
Were they also used in '89???? I thought the '128' heads were 87~89.
With those heads on your engine, you're right back to 250 HP like your Vette had when it was new if it has '113' heads and flat top pistons.
They aren't giving any camshaft specs but that could affect the power output.
The description sez it has Vortec heads.
Were they also used in '89???? I thought the '128' heads were 87~89.
With those heads on your engine, you're right back to 250 HP like your Vette had when it was new if it has '113' heads and flat top pistons.
They aren't giving any camshaft specs but that could affect the power output.
The description sez it has Vortec heads.
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Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
I disagree about stock 113 heads flowing similar to Vortecs. Out of
the box, the Vortec flows considerably higher values across the lift spectrum.
(But it doesn't matter really given what your car has.)
0.200". - 0.300". - 0.400". - 0.500".
120/096. 160/123 . 186/140 . 196/155. - 163cc (L98 TPI w/58cc & 1.94/1.50) Also known as D-port 113's
139/105. 190/137 . 227/151 . 239/160. - 170cc (885 Iron Vortec w/ 64cc & 1.94/1.50)
On the 330HP crate motor, one difference is that the 58cc 113's will
produce higher compression than the 64cc Vortecs.
You really need to say more about the rest of the car and what the
intended application is.
If you were prepared to use a hood bulge of some sort, the Holley
Stealth Ram has worked well - it just does not fit under the hood.
Some other choices are the Mini Ram (high RPM, no EGR), Super Ram
(good all round performer, greater installation difficulty and currently
out of production), a single plane intake that has been converted to
EFI, or a traditional carb & intake that replaces the current EFI.
There has been extensive discussion about each here.
Are you sure the bottom end is from the 330HP package?
.
the box, the Vortec flows considerably higher values across the lift spectrum.
(But it doesn't matter really given what your car has.)
0.200". - 0.300". - 0.400". - 0.500".
120/096. 160/123 . 186/140 . 196/155. - 163cc (L98 TPI w/58cc & 1.94/1.50) Also known as D-port 113's
139/105. 190/137 . 227/151 . 239/160. - 170cc (885 Iron Vortec w/ 64cc & 1.94/1.50)
On the 330HP crate motor, one difference is that the 58cc 113's will
produce higher compression than the 64cc Vortecs.
Originally Posted by Simmons-Racing
What would you recomend for the intake ? What else would you
recommend to make more power with this engine/head setup ?
recommend to make more power with this engine/head setup ?
intended application is.
If you were prepared to use a hood bulge of some sort, the Holley
Stealth Ram has worked well - it just does not fit under the hood.
Some other choices are the Mini Ram (high RPM, no EGR), Super Ram
(good all round performer, greater installation difficulty and currently
out of production), a single plane intake that has been converted to
EFI, or a traditional carb & intake that replaces the current EFI.
There has been extensive discussion about each here.
Are you sure the bottom end is from the 330HP package?
.
Thread Starter
Instructor
Joined: Feb 2007
Posts: 112
Likes: 0
From: Macungie PA
I would like to build the car to run 1/4 mile and Auto-X sometimes. I plan on getting LT headers and exhaust. I have a Tag on my block with the part # and build date of the engine and it is the 330hp part number.
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
If I had the intake to support them I'd lot rather have the Vortec heads. A lot more combustion chamber swirl makes the cylinder charge burn better for making more power. The combustion chamber shape is better than the 113 heads too.What was the design goal of that 'block' in the chamber between the intake and exhaust side on the 128 and 113 heads???
I'm don't think I understand that at all.
A Vortec head engine with TPI on it, now that DOES sound interesting.
Anybody want to take a guess at what the CHP is on it?
310? 325?
What intake?
That's basically determined by where you want to make power and as stated, what you want to do with the car.
Higher RPM or lower RPM?
That's also going to determine the camshaft specs (and the gear ratio).
In a nutshell:
High RPM _____________
1) Mini Ram
2) Converted LT1 ... about the same as above
3) StealthRam won't fit under the stock hood
Camshaft: Intake & Exhaust duration 220*~235* @ .050
Low RPM__________
1) Stock TPI RPM or more accurately Intake Limited
2) Modified TPI Larger Base & RUnners Still Intake Limited
3) SuperRam
Camshaft: Intake & Exhaust duration 205*~225* @ .050
205 is close to stock, not too good.
None of that is 'written in stone', it's just a general guidline.
You'll want (need?) an EPROM to make most any of the combinations run 'just right'.
Team Owner
Joined: Sep 2001
Posts: 62,097
Likes: 1,724
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I would recommend you read my website and decide where you want to end up with the car, before you start looking for intakes. The cam you have in there may also affect your decision, and whether or not you ever wish to change that.
Burning Brakes
Joined: Oct 1999
Posts: 1,236
Likes: 91
From: Pittsburgh,PA
As soon as I finish with the clutch and headers on the new 388 engine I will be getting it dynoed as well. I'm running modified Vortec heads and the superram on it.
Dave
Last edited by opel; Mar 7, 2007 at 08:52 AM.
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Keep in mind running the Vortec heads will require a new $400 TPI baseplate, or machining new holes in the heads.
Makes me wonder how hard it would be to just put the Vortec holes into a stock intake.
Makes me wonder how hard it would be to just put the Vortec holes into a stock intake.
Advanced
Joined: Feb 2005
Posts: 77
Likes: 1
From: zanesville ohio
imo the vortec heads are better than 113 heads, but some people don't like the extra weight, as far as power you can get 330 hp with a modified tpi on the gm 330 hp crate motor. I think a lot of people start getting crazy about the weight issue of iron heads, when in reality unless you plan to have a serious race car it doesn't really matter, and if you want some real heads that are aluminum go with brodix, but 330 hp is plenty for the street. 
Le Mans Master
Joined: Jan 2002
Posts: 9,036
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From: Edmonton AB
While it would be easier than your project of changing transmissions,
my vote favours buying a Vortec intake rather than converting a 23º intake.
.
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
64cc to 58cc seems to increase compression from 9.0:1 to about 9.6:1.
I am using the following entries to arrive at the 9.0:1 CR published
for the 330HP engine w/ Vortec heads.
- the Vortecs have 64cc chambers,
- the bore x stroke is 4.00" x 3.48"
- the gasket bore is 4.03"
- the gasket is about 0.041" compressed
- the deck clearance is about 0.020"
- the piston dish volume is 13cc (ie: -13)
Then, when chamber size is reduced to 58cc to represent the
#113 heads, compression is reported as 9.563:1
While the component volumes may vary from what is actually
present, my vote is that for estimating the effect of a change
in chamber volume on compression ratio, these will suffice.
Here is a thread with values for the L98 that may be informative.
Basic piston head measurements 91 L98
Another thought worth mentioning is the rule-of-thumb about
aluminum heads being able to tolerate approximately 1 more point
of compression, compared to iron heads - all else being equal.
.
