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327 buildup questions?

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Old Aug 5, 2004 | 05:59 PM
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Default 327 buildup questions?

I would like to build a 327 and was wondering if you guys could give me some good ideas.I would like a 327 with around 350-400hp at the flywheel.I would like a combo that can rev a moderate amount as I hear 327s can.I would like to make power in the upper RPM bands of 6-7000rpms.I'm trying to get ideas on what heads/cam packages.I would like something I can buildup on later as this will more than lickely be a budget build.
Thanks for the help guys.
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Old Aug 5, 2004 | 06:43 PM
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You don't build a 7000 rev 327 on a budget, however, I have dyno sheets on a '65 L-79 that was meticulously rebuilt with Crower Sportsman rods, OE type forged pistons with a composition head gasket, head chambers and decks equalized for a measured 10.35:1 +/-0.1 CR, LT-1 cam, very nicely pocket ported/port matched OE 461 heads with a three angle valve jjob, OE 2.5" exhaust manifolds, and OE L-79 inlet manifold and 585 CFM Holley.

Peak SAE gross power on a lab dyno was 359@6400, the imposed redline for the testing, and it was still climbing. It also made 80 percent peak torque at 2000, with just a slight drop down to 1500. The top end of the 80 percent torque bandwidth was beyond the redline.

Duke
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Old Aug 5, 2004 | 09:11 PM
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Originally Posted by SWCDuke
You don't build a 7000 rev 327 on a budget
Duke
While it's possible to build such an engine on a "budget", you might need another budget to do it right when it breaks. With the right pieces, you can reach your power goals without having to wind it beyond the safe limits of standard parts and that power will also be where you can actually enjoy it. If you really gotta have a 7k rpm engine, do yourself a favor and open your wallet for the "good stuff".
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Old Aug 5, 2004 | 11:07 PM
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Thanks guys.What is a more reasonable RPM range?I had heard that 327 loved to rev.What heads should I look into.I may start with 2.02/1.60 double hump heads but change later.I would like to run a higher CR.But still be able to run 93 octane.What about cams?
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Old Aug 6, 2004 | 12:27 PM
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See my combo for my 331 CI in the C3 section (post your combo here). Car dynoed at 293 hp/293 ft-lb at the wheels which is about 375 hp at the crank. This is at a very reasonable 5,500 rpm with a 327/350 hp hydraulic cam. This is more power than some of the 350+ CI engines are making with far more radical combination and solid cams. If you want to get to 6,500+, you need a solid cam and the regular adjustments that go with it.
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Old Aug 6, 2004 | 01:04 PM
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Originally Posted by blackLS1
Thanks guys.What is a more reasonable RPM range?I had heard that 327 loved to rev.What heads should I look into.I may start with 2.02/1.60 double hump heads but change later.I would like to run a higher CR.But still be able to run 93 octane.What about cams?
just curious what you consider a "budget". i am after a similar result with the one I am building so far it looks about like this.
heads $1000
Manifold, $220
Carb, $125
Cam $200
pistons, $250
bolts, $200
WP $50
Used Block with rods, cam , pistons, oil pump, crank, etc... $200
block prep and balncing assemblies, $550
Misc $ 400

stuff i bought and didn't use, $400 (carb, cam )
ended up using the crank, rods and timing stuff i bought with the block, a 350 4 bolt main one.
To me this was budget but i am not unhappy with the stuff i bought, weather i am putting it together right is another question that time will tell. i used friends, e bay, the forum here and the local speed shop as a parts/ info source. i obviously squandered $400 by changeing my goal after i started. i wold suggest you don't do that. good luck
PS i am sticking in a rev limiter with the MSD. probably at the 6500 mark maybe lower. depends on what the dyno tells in the end.

Last edited by panchop; Aug 6, 2004 at 01:17 PM.
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Old Aug 6, 2004 | 08:45 PM
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Panchop that sounds about like how much I would like to put into it.I may go with old style heads and update the combo at a latter date.
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Old Aug 9, 2004 | 09:59 AM
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I am thinking this combo will get you to 350 HP. You may want a little more cam to get the power band in the higher RPM's. Remember, the cam duration will act as a "larger" cam in the 327 compared to the 350.

* AFR 180 heads.
* Have your engine blue-printed for a zero-deck 10:1 compression ratio (high quench).
* If you have the money, use a hydraulic roller cam with specs of 110 lobe seperation/218 intake duration & 223 exhaust duration @ 0.05 lift.
* 1-5/8" Headers
* Edelbrock Performer RPM manifold and 750 cfm carb.

This combo produces approx 430 HP in a 350 according to the AFR website. Should be able to produce 350 HP in a 327 I would think.
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Old Aug 9, 2004 | 11:55 AM
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Identical engine configurations except stroke will produce about the same peak power at the same mean pistons speed, so an identically configured 327 will make about the same power as a 350, but at higher revs.

This is why 327s and more so 302s are known as "revvers".

I seriously doubt the claim that the configuration you quoted will produce over 400 SAE gross horsepower, but whatever the peak power in a 350 CID version shortening the stroke to 3.25 will result in about the same peak power about 500 revs higher.

Duke
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Old Aug 9, 2004 | 10:10 PM
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Originally Posted by SWCDuke
Identical engine configurations except stroke will produce about the same peak power at the same mean pistons speed, so an identically configured 327 will make about the same power as a 350, but at higher revs.
I am not sure if I understand that. With less stroke, you have less displacment, that will decrease overall power, will it not? Using that logic, a 383 will produce the same power as a 355 but at a lower RPM?

Originally Posted by SWCDuke
I seriously doubt the claim that the configuration you quoted will produce over 400 SAE gross horsepower...
I just copied it from the AFR website, not sure if it is gross or not. Regardless, this is the DD2000 inputs and the power outputs:

327 cu in
AFR 180 heads
10:1 compression
Dual plane intake
750 cfm carb
Small-tube Headers w/ Mufflers
Comp Cam 270HR (hydrallic Roller - 218/224 duration 0.495/0.502 LIft)

RPM HP TQ
2000 128 336
2500 165 346
3000 205 358
3500 251 376
4000 295 387
4500 335 391
5000 365 383
5500 383 365
6000 385 337
6500 374 302
7000 351 260
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Old Aug 9, 2004 | 10:15 PM
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so 6000 is all thats needed
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Old Aug 9, 2004 | 11:00 PM
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Thanks for the info guys.I have always had people say that if you build a high RPM motor to be sure to use the good stuff so it will stay together.Can someone list the goodstuff?Something I can research and read about.I'm beginning to get ideas on what I want to put together.
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Old Aug 10, 2004 | 11:33 AM
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Originally Posted by 69stingray
I am not sure if I understand that. With less stroke, you have less displacment, that will decrease overall power, will it not? Using that logic, a 383 will produce the same power as a 355 but at a lower RPM?
Head flow is the limiting factor and they become choked (Mach index at about 0.55) at the same airflow, which will occur at the same piston speed. Taylor's IC engine textbook has a more thorough explanation. It's available from SAE and many other sources (do a google search under Charles Fayette Taylor)

It's important to note that this applies to engines that are identical other than stroke. For a longer stroke engine you can go with a slightly longer cam and a larger carb without increasing the beginning speed of the 80 percent torque bandwidth, so you can usually get a little more power out of them at a slightly higher mean piston speed than a short stroke engine, especially if you have really good heads.

Duke
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Old Aug 13, 2004 | 06:30 PM
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What about vortec heads?Has anyone had any experiences with them?They are pretty cheap and I could get the AFR heads later.Does anyone have any idea about how much the AFR heads will cost.Also lets talk about cams.What would be a good cam?
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Old Aug 13, 2004 | 08:50 PM
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Vortec heads make a nice street head, but there are some things you need to consider if your ultimate goal is to run the AFR heads at a later date.

1. The Vortec heads require a vortec-specific intake, which is not compatible with the AFR heads.
2. Out of the box, Voretc heads are only good for .460", without the rist of retainer to guide interference. The Vortec heads can be modified to accept larger cams, or can be purchased at a higher price already set-up for high lift cams. Both options will add considerably to the cost.
3. Properly set-up Vortec heads will probably run you close to $600 by the time you're done, then you need to purchase the intake. You'll be into this combo close to $800. At this point there are aftermarket heads that out perform the Vortecs, for not much more money. TFS 23* heads are a good, budget choice, and they use a traditonal SBC intake. Speaking from experience, it's a lot cheaper in the long run to plan for and ultimately build the combo you want the first time.
4. A while ago, in the C1-C2 forum, they were discussing manifold height with Vortec heads. The consensus was that the Vortecs placed the carb slightly higher than traditional 23* SBC heads for a given intake. If you have hood clearance concerns, this is something to consider.

Personally, I think the Vortec heads are great on the street, but if your ultimate plan is to step up to a better head in the future, I'd by-pass the Vortecs altogether. JMHO Wes
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Old Aug 13, 2004 | 09:09 PM
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Originally Posted by blackLS1
What about vortec heads?Has anyone had any experiences with them?They are pretty cheap and I could get the AFR heads later.Does anyone have any idea about how much the AFR heads will cost.Also lets talk about cams.What would be a good cam?
Like I noted before, you don't need exotic heads or cams. My mild combo did 293 hp/293 ft-lb at the wheels on the dyno in 81 degree F. temperature using modified stock heads and a 327/350 hp cam. This equates to about 375 hp at the crank. This is lots more power than most 350s with vortech heads and more aggressive (and even solid) cams are doing. (Most ZZ3/ZZ4 owners report 225-250 hp at the wheels.) This can also be built up over time to avoid a big initial outlay.

Personally, I think the power is coming from the way in which the heads were hogged out and pocket ported. The stock 1.94 valve heads have a higher velocity to promote torque than the stock 2.02 heads and porting these out to 2.02 gives them the flow while retaining the velocity. The fact that they are iron better keeps in the heat of combustion than aluminum heads.

My combination:

331 CI, pump-friendly 9.5:1 CR
K&N 14"x4" air filter, Corvette drop base and lid
Holley 600 dp, choke horn milled, nickle plated
1" Aluminum open spacer, exterior polished
Edelbrock Performer RPM, port matched, exterior polished with all extraneous castings and lettering removed
Homemade lifter valley splash shield to keep hot oil off manifold bottom
Camel hump 1.94/1.50 heads hogged out to 2.02/1.60, pocket ported, port matched, pump-friendly hardened seats, 3-angle valve job
Comp Cams 1.52:1 roller-tip rockers
Crane Cam Vintage Muscle 327/350 hp cam, 222 degrees @ 0.05, 0.443" lift (with 1.50 rockers)
Doug Thorley headers, dechromed and ceramic-coated
2.5" mandral-bent exhaust (including tips), 2" cross-over just before rear axle
Mallory Hyfire IV CD ignition box triggered off Accel points
Mallory high voltage chrome coil
Mallory spiral-wound coil wire
Mallory solid copper plug wires
Champion plugs
37 degrees total ignition advance
Carter high-volume fuel pump
Melling high volume oil pump
Polished aluminum GM high flow water pump
Flex fan with polished aluminum spacer
Polished aluminum one-wire 100 amp alternator
Muncie M-20 CR 4-speed
3.70:1 positraction

Car recently did 293 ft-lb and 293 hp @ 5,500 rpm at the wheels on the chassis dyno. Engine pulls to 6,200 rpm and does over 200 ft-lb from 1,900 rpm. This was prior to some clean-up work around the junction of the carburetor and base of the air cleaner that smooths the flow through this area and should be good for a few ponies. Car has run 107 mph in the high 13's (bad tires) at the quarter and is probably faster now. Car is extremely streetable and could probably even run 87 octane if it had to. (I can't get the engine to ping no matter how far I advance the ignition.)

I've just done some modifications in the area of the carburetor/air cleaner base interface that substantially smooths the flow through this area and I would now expect about 300 hp at the wheels. (I took lots of pics and am considering doing an article.)

The secret to power is in the details and air flow. For example, when an intake and heads are matched to a gasket, and each other, there is still some "slop" in how the manifold lays on the heads such that you can end up with a ridge at the interface. However, if one really takes the time and knows how to do it, the interface can be seamless. Most shops won't take this kind of time.
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Old Aug 13, 2004 | 10:46 PM
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Originally Posted by toddalin
The secret to power is in the details and air flow.


That's why guys are always quoting some awesome et for their favorite muscle car (and believe they came that way from the factory). While the typical factory stock `60's -early `70's muscle car might be hard pressed to get into the 14's, we're always hearing about 12 sec GTO's. Z28's, etc.. There's a lot of power to be had in the "details" and there's also a lot of et reduction to be had in gearing and chassi prep.
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Old Aug 17, 2004 | 09:30 PM
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I too just finished having my 327 built this winter. I let my builder go at it... .040 over 350 crank w/ the mains machined to small journels, 1.94 and 1.50 valves, 3 angle valve job, 240/240/480/480 cam with 108 degrees of seperation.. BG SD 650 mech sec and Mallory mech adv dist. I have the adv set at 11 degrees initial. 10:1 compression. I run only 93 pump gas. I have the tremec 5 spd and 3:70 rears. This car fly's. I ran it the other night for 3 passes in the 1/4 and my best was 13.7 at 99 mph. If I would really romp on it I think that it would go to the low 13's...
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Old Aug 18, 2004 | 08:49 PM
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Originally Posted by youwish2bme
I too just finished having my 327 built this winter. I let my builder go at it... .040 over 350 crank w/ the mains machined to small journels, 1.94 and 1.50 valves, 3 angle valve job, 240/240/480/480 cam with 108 degrees of seperation.. BG SD 650 mech sec and Mallory mech adv dist. I have the adv set at 11 degrees initial. 10:1 compression. I run only 93 pump gas. I have the tremec 5 spd and 3:70 rears. This car fly's. I ran it the other night for 3 passes in the 1/4 and my best was 13.7 at 99 mph. If I would really romp on it I think that it would go to the low 13's...
I see you are from Clayton I live in Smithfield.Who was your engine builder?I would like to talk with different builders to get a idea on the buildup.What car do you have it in and what track did you run at?
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Old Aug 18, 2004 | 09:53 PM
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I used Joey Ball of Ball Machine in LeGrange/Kinston.. If you head out 70E before you get to Kinston he is on the right across from the ughhhh FORD dealership... He was the most straight forward person that I ran into.. He builds drag motors, circle track motors but has a sweet spot for classics... I ran it in the car in my sig.. 66 vert... at Freaky Friday down in Fayetteville two weeks ago... Dave Hitchens....
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