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Technical 327 Cam Recommendation

Discussion in 'The Hokey Ass Message Board' started by Dan Hay, Jun 13, 2020.

  1. I have filled out a cam recommendation on the Comp website. I have a specific grind in mind, but I respect the collective experience and knowledge here so I'll throw it out to you all.

    Specs:
    .030 over 327 (332 CID)
    Flat top pistons
    Stock rods & Crank
    Edelbrock Performer RPM heads. 64cc chambers, 195cc intake runner volume, 2.02 intake -set up for flat tappet. But I think I can run a roller cam if I change the valve springs.
    Induction: most likely a single four barrel. Possibly dual 4s.
    Car: 38 Chevy Coupe, around 3,000 lbs. curb weight
    Uses: street performance. The car will have power brakes and A/C Most likely a 1500- 6000 rpm range.

    Transmission and gear: it currently has a TH400 and a 3.08 rear gear, but those might change as I'll have the car apart when I do the motor. I have a fresh 700r4 also. I'd really like to put a manual trans in it, but I don't think I can afford it right now. If I go with the 700r4 I go to a 3.73 gear.

    History: this car used to have a 350hp 327. And it had some stomp! Back in 89, my dad tamed it way down, got rid of the good heads in favor of some 76cc smogger heads, and a HO 305 cam. (I believe it's called an L-69) Took out the domed 11:1 pistons in favor of the flat tops. It's been boring, but reliable ever since. I want to put the stomp back in this car.
     
    Last edited: Jun 14, 2020
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  2. 4 pedals
    Joined: Oct 8, 2009
    Posts: 687

    4 pedals
    Member
    from Nor Cal

    Well nobody else has answered yet so I'll throw my 2 cents in the ring. There are quite a few other cam manufacturers. I would suggest checking with all that will answer the phone or email. Some are owned by the same conglomerate, but have different cam designers. Lunati, Crane, Crower etc.

    What type of cam are you looking for? Flat tappet or roller? Hydraulic or solid?

    Assuming that it hasn't been decked to match the flat top pistons, you should have something like 9:1 compression. That's not much. Do you still have the 11:1's that came out of it?

    A lot of guys may suggest the L79 lo known as 327/350 hp cam, which is fairly mild, or the Duntov Cam also known as the 30-30 solid. Personally I wouldn't run a flat tappet cam these days.

    You didn't mention induction system, so we don't know what you have for a manifold and carb. With your drivetrain and mild compression, I'd be looking for a hydraulic roller in the 250's range seat to seat and probably 195-205 @.050. preferably on a 108 LSA. Take as much lift as you can get for that.

    If it were mine, I would get the compression to an honest 11:1 and look for a solid roller in the 290 range seat to seat, 240 or so @ .050. Change the rear gears to something that begins with 4. That would give it the jump out of the hole you're looking for. Gear it to run no less than 3000 at 65 mph. with a straight drive trans, or 2500 with overdrive. Edelbrock Performer RPM intake with 750-800 cfm double pumper would make it happy.

    Devin
     
    Dan Hay likes this.
  3. Mike VV
    Joined: Sep 28, 2010
    Posts: 1,908

    Mike VV
    Member
    from SoCal

    AAAgh, the 3.08's gotta go.
    Especially if you use a 4spd., automatic. Then the recommendation is a 3.70 gear by all trans. sellers.

    I've put 3.70 gears in my two four speed automatic transmission cars.
    The lowest gear would be a 3.55 for anyone wanting to have fun driving their car.

    That is unless you're out to do 150mph freeway runs..!

    Mike
     
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  4. Ericnova72
    Joined: May 1, 2007
    Posts: 367

    Ericnova72
    Member

    I see a lot of guys making this mistake....the Duntov cam and the 30-30 cam are NOT the same cam....not even close.
    Nearly 30° more duration on the 30-30, and more than 1/16" more lift.
    This mistake has been repeated so many times even some cam grinders mess up put the Duntov name in the 30-30 description.
     
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  5. While the Duntov 097, 30-30 and the L79 350hp cam are legendary and traditional, I'm open to modern cam grinds, as technology has come a long way.
     
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  6. Jmountainjr
    Joined: Dec 29, 2006
    Posts: 1,095

    Jmountainjr
    ALLIANCE MEMBER

    Flat top pistons is a pretty vague description. A number of recent posts about guys getting burned by OEM compression height vs. rebuilder pistons with much lower CH. So to ballpark the compression ratio you need to know how far the pistons sit down in the bore at TDC. Realistically with most current gas available it hard to get much more than 9.5:1 for a reliable daily driver. And pay attention to quench dimensions. Compression ratio will influence your cam choice.
     
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  7. That's a good point, I will measure piston to deck height when I tear it apart. They are not OE GM pistons. I don't want more than 9.5:1 CR, this needs to run on the 93 octane available to me.
     
  8. pitman
    Joined: May 14, 2006
    Posts: 4,918

    pitman

    In a lighter A coupe, the 340 hp Chev cam gave fabulous mid-range performance. 45 years ago, I ran 3.08's and a wide-range Muncie.
    4 th was a 1 - 1 overdrive.
     
    Last edited: Jun 14, 2020
  9. Buy an expensive modern cam I'll show up with my L-79 cammed 355 and blow your doors off.

    I don't know what comp cams is selling you or who told you that you have to change valve springs to run a roller cam but I guess no reason to go into that. The L-79 cam is good off idle- 5200 RPM set up stock. With a 6200 red line. We are spinning ours to 7K+ no problems but it is not in a stock assembly line motor. The Comp cam salesman has probably given you good advice. I would go with that and be happy.
     
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  10. greybeard360
    Joined: Feb 28, 2008
    Posts: 1,458

    greybeard360
    Member

    I would look hard at this cam.....
    Voodoo Hydraulic Flat Tappet Cam & Lifter Kit - Chevrolet Small Block 268/276
    SKU
    10120703LK
    Hydraulic. The most awesome 268 cam ever produced! Out-powers all others! This High Performance street cam likes 2400 RPM stall, 700 cfm carb, dual plane intake and headers. Makes un-equaled power to 6200 RPM with proper valve springs. If you're looking for a Very Strong cam with great street manners then this cam is it.; Advertised Duration (Int/Exh): 268/276; Duration @ .050 (Int/Exh): 227/233; Gross Valve Lift (Int/Exh): .489/.504; LSA/ICL: 110/106; Valve Lash (Int/Exh): Hyd/Hyd; RPM Range: 1800-6200; Includes: Cam & Lifters

    I have used the VooDoo cams in several motors... they are impressive!
     
    Dan Hay likes this.
  11. Mike VV
    Joined: Sep 28, 2010
    Posts: 1,908

    Mike VV
    Member
    from SoCal

    Remember, you are building a "combination..." of parts. All of the parts NEED to work well together for the best overall performance.

    The parts that you are talking about using, camshaft... and 3.08 gears...do NOT go together. At least not as far as any sort of good performance goes. Check the cars that used the cam(s) you are looking at, see what gears they used from the factory..!
    Aftermarket cam, normally recommend a gear ratio, better check it, otherwise, you'll think that the cam isn't performing, when in reality, you've choked it with the rear end gear ratio.

    Just a heads up...

    Mike
     
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  12. sunbeam
    Joined: Oct 22, 2010
    Posts: 4,839

    sunbeam
    Member

    The L79 has been around sense 65 but is still one of the best all around street cams for a 327 unless you want "the idle" pretty wide LDA gives a smother idle If you want solids I love the idle of the 97 and I would spring for the lifters with the oil hole in the face. More oil on the cam lobe has got to improve cam live.
     
  13. 6-bangertim
    Joined: Oct 3, 2011
    Posts: 375

    6-bangertim
    Member
    from California

    Tire and wheel size? A tall 75-series tire on a 15 or 16" wheel would make the 3.08 feel like a 2.76! CHEAPEST thing to do right now is put the 3.73's in, then go drive the car. Use Googlemaps to monitor your speed as you look at the tach - note the RPM's at the freeway speed the car settles-in best, for a BASELINE to start with. Could be, that more gear is all you need for that 'stomp' factor to return some...

    Go buy a cheap FI 305 to keep the car on the road. Pitch the FI for a freebie cast intake, carb, install the HO cam you have for a couple more beans. Run as much timing lead as you can for 89 or 92 gas, without pinging or hard starting in summer heat. Then GET SERIOUS with the 327 build - your current compression will limit how big a cam you NEED, but not the cam you may want! Figure out your current STATIC compression, then learn about the theory of DYNAMIC compression - that may help you decide if the 'stomp' you're after is worth 10:1 pistons, big cam, carb and intake to feed it. IT is all a combination of the CORRECT parts, gearing and tire size, transmission, to get the desired results - I would focus on building TORQUE and throttle response, and if what you want is within your budget.

    There's a sayin' from my roundy-pounder days that still applies - "Horsepower sells parts, but TORQUE wins races!"
     
  14. Many of you have commented about the 3.08 gear. That is most definitely going away. This car is getting a full drivetrain overhaul, not just the motor. The car has been on the road since 1979, with the engine detune/overhaul in 1989. Everything leaks and all the bushings are wore plum out so this is the full on 40 year refresh.

    That being said, I can pick and choose the right gear, transmission (My choices at this point are TH400 or 700r4) and anything else drivetrain related is an open for discussion, I'm going to take my time and do it right.
     
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  15. I thought I read in the paperwork on the heads from Edelbrock that they are for a flat-tappet cam, and the valve springs needed to be changed for a roller. They came fully assembled from Edelbrock. The Comp guy didn't tell me that. I haven't investigated it further.
     
  16. bigdog
    Joined: Oct 30, 2002
    Posts: 533

    bigdog
    Member

    If you want traditional I've a 10:1 small block with the 327/350 cam and I love it . Lots of power and sounds great at idle. If you want modern then figure out your combination and talk to the cam manufacturers.
     
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  17. Ericnova72
    Joined: May 1, 2007
    Posts: 367

    Ericnova72
    Member

    Too bad you've already bought the Edelbrock RPM heads....you could have gotten much better flowing head for the same or less cost.
    Edelbrock is coasting, charging guys premium price for outdated technology just because it has their name on it.
     
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  18. Thanks for adding absolutely nothing helpful to this thread. It's not really any of your business, but the heads came up for sale at about 30% of retail locally, so I jumped on them.
     
  19. Ericnova72
    Joined: May 1, 2007
    Posts: 367

    Ericnova72
    Member

    Well, you said you want the car to "stomp"...but went and bought a head that doesn't flow any better than a stock Vortec head.

    I'm just saying a lot of guys should come to boards and ask questions before they buy anything....some local "good deals" aren't as good as you may think. It happens all the time..

    For your engine and goals, I'd be running some form of solid flat tappet if I wasn't going to use a hydro roller...I would not even consider hydraulic flat tappet. Low to mid .500" lift, high torque tight lash solid with edm hole lifters. Not any factory solid grind....but everyone has different tastes.
     
  20. Roothawg
    Joined: Mar 14, 2001
    Posts: 19,687

    Roothawg
    Member

    Dan,

    FWIW avoid the solid roller on the street. It's not what you need. Solid rollers are for weekend cruisers and strip cars. Stay with a hydraulic. You actually drive your car. There will be 1,000 different ideas and everyone has a preference. You need to call and talk to the guys at Bullet Cams. Explain to them what you want and they will grind a cam for you. It's the same money as an off the shelf cam. The guys are super helpful and will get you the end result you need. Forget all of the "You have to run a XXXX".

    Your little 327 will be peppy enough with a few go fast parts.
     
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  21. DDDenny
    Joined: Feb 6, 2015
    Posts: 13,417

    DDDenny
    Member
    from oregon

    327/350 hp, Muncie M-20 four speed(wide ratio), 3.55 (ish)rear, in my eyes you couldn't ask for a better combo.
     
  22. steeltappet
    Joined: Jan 3, 2010
    Posts: 54

    steeltappet
    Member
    from PA

    I have filled out a cam recommendation on the Comp website. I have a specific grind in mind, but I respect the collective experience and knowledge here so I'll throw it out to you all.

    Specs:
    .030 over 327 (332 CID)
    Flat top pistons
    64cc chambers, 195cc intake runner volume, 2.02 intake -set up for flat tappet.
    Induction: single four barrel.
    Car: around 3,000 lbs. curb weight
    Use: 1500- 6000 rpm range.
    I figure this is just shy of 10:1 with the head gaskets.

    Your engine is similar to what I am just finishing and trying to tune and adjust.
    For comparison, I was looking at a couple of the same cams as you are.
    I went with the Comp cam 270 mechanical. It seems too mild compared to the old 90's 280H Lunati that was in my old 9:1 motor.
    The idle is fairly smooth with 15" vacuum at about 900 rpm,with a 650 vac secondary carb on 2101 Edlebrock dual plane.
    Am trying a tighter lash and addressing some initial issues. I had a pinch nut back completely off within the first hour of run time.
     
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  23. 6sally6
    Joined: Feb 16, 2014
    Posts: 1,105

    6sally6
    Member

    Here's me nickels worth.........With Alum. heads & a somewhat snotty camshaft 10:1 or 10.5:1 is not really radical for hi test fuel.
    Most guys say....."9.5:1 is max for a street car and pump gas" Well that's 'pretty-true' with IRON heads and a cam with 112* LSA!!!
    Tight LSA's tend to 'bleed-off' CR at low speeds(around town 30mph stuff... were it can cause damage from pinging. ( 110-108* LSA is considered tight)
    Alum. heads do NOT hold heat like iron heads do...... they displace it quicker(remember science class). HEAT in an engine induces pinging....Alum heads displace heat and so NEED higher CR. That's why they recommend higher CR numbers for Alum heads.
    Big cams need lotsa initial timing. 16-18-20*initial and 16-20* mechanical advance is NOT unusual.
    Do your home work.........read about timing curves.......duration & LSA in camshafts...(big lift numbers really ain't ALL that important on a street engine) Cam timing advance/retard
    Look at cam grinds for dirt-track engines. (quick acceleration from nearly off idle low speed.......sound familiar? A lot like a hot street engine!) Learn it and then you can talk to a cam company rep and KNOW what your talking about.
    Some of the guys that answer the phone know about SALES more than engines. They tend to read off notes that someone gave them. Just like...."a Chevy grind doesn't necessarily work the same in a Pontiac or Ford..."but that's what most of the phone salesmen push.
    Do some serious homework...or "you're just trying to poke your finger in a hole in the dark..blindfolded"
    6sally6
     
  24. Fogger
    Joined: Aug 18, 2007
    Posts: 1,471

    Fogger
    Member

    6SALLY6 offers you the best advice so far. When building an engine for a specific car all the variables must be taken into consideration. Guessing what to use and not taking advantage of professional recommendations will cost you money, time and frustration.
     
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  25. That's a good point about dirt trackers @6sally6 Torque off idle and the rpm range they run is very similar to a hot street motor. And I had forgotten about the heat dissipating properties of aluminum... much to ponder. I appreciate the input.
     
  26. lippy
    Joined: Sep 27, 2006
    Posts: 4,571

    lippy
    Member
    from Ks

    Bullet cams. JMO. Lippy
     
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  27. sunbeam
    Joined: Oct 22, 2010
    Posts: 4,839

    sunbeam
    Member

    I remember when Car Craft tested some of the hot rod rules with dyno pulls one was the aluminum vs iron compression thing. They could not find any difference in power or detonation. It was a 10.5 SBC
     
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  28. I run one in my 355 and like it. It has a subtle idle, enough to be heard and great street manners. I went with the Holley 700, have the gears but no headers. The pull at WOT is impressive.
     
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  29. 1971BB427
    Joined: Mar 6, 2010
    Posts: 5,674

    1971BB427
    Member
    from Oregon

    Just went through this last year on my own '39 Chev coupe build. Mine is a 350 SBC with a 700R4 behind it, and 3.73 Ford rear axle.
    I chose to go with a Howards roller camshaft, which is the first roller cam I've ever used. But I was tired of cam break in, and also wanted some power, while having reliability too. And not worrying about zinc additives, or cams going flat.
    For heads I chose the cast iron version of the LT1 heads; the 487x heads. I wanted the advantages of better flow that the 76cc combustion chambers give, plus the ability to run pump gas easily and not run premium and still need octane booster or race fuel added as my 350 in my Austin gasser needs!
    The machine shop put hardened seats, stainless steel valves, screw in studs, and all new springs in my 487x heads. With my flat top pistons my engine is at 9.25:1 compression. These heads flow a bit over 180 cfm runners. Equal to many aftermarket heads, but not so much as to lose bottom end. I personally have had plenty of time with high compression engines for the street, and they're not fun after awhile. Having issues with getting enough octane just makes enjoying a car tougher, and going down in the 9.0-9.75 cr range will make life simpler, and the driver happier.
    The cam spec'd by Howards is a 1800-6000 rpm rated hydraulic roller. It has advertised 280/288 duration, and .530"/.535" lift. 109 LSA. I don't consider 109 LSA as "tight"., but anything less is in my book. It works with a stock torque converter also.
    The engine pulls hard off the line, and still has plenty of power to spin the 9" cheater slicks when it shifts from 1st to 2nd, and from 2nd to 3rd also. These old coupes aren't exactly light, so it's nice to have a cam that pulls well out of the hole with a SBC engine. I'm running an Edelbrock Performer RPM with a Quick Fuel 650 cfm double pumper carb.

    [​IMG]

    [​IMG]
     
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