Here's the recipe:

'69 block, crank, rods, new cast pistons

NOS TRW 50135 oil pump

reworked 461's w/ 1.94/1.5 valves

Harold's 264F10 - 232/232 @.50; .470/.470 lift, Z-28 142 springs

Performer, Weiand 8004 or Holley 300-36

Probably a Q-Jet (depending on intake)

Rebuilt HEI

Hedman headers w/ 2 1/2" Flowmaster pipes w/ bypassed H-pipe and Summit turbo mufflers

This will end up in a 66 4dr w/ TH350, 27" tall rear tires, and eventually 3.55 or 3.73 gears (has a 3.08 now).

Cam ok for off idle acceleration? Works at about 2000-6500.

What stall converter? 2200-2400 RPM?

Which intake would you suggest?

I'd dump the cast pistons. They will screw up the quench distance. Hypers with the correct pin height are a better way to go. Forged are best but more money.

I'd be reluctant to go over 216-220 degrees duration in a 327 if you want off idle torque. Go with a 2400-2600 stall converter.

A stock 1969 Chevy intake will work great. If not, use an Edelbrock Performer.

Cast will certainly hold up, but like Pat, I wonder about the quench. Speed Pro makes an excellant hypereutectic with a black coating on the skirts.

Mike

That's Harold's old 264 solid lifter cam so I would think it should act smaller then the same sized hy- cam, imho.. But he did tell me that it would act like a 280 hy- cam but I don't see how???

The Holley 300-36 true high-rise takes a square carb. whereas the more like an E-brock Performer, Weiand 8004 is a spread bore. And it is supposed to be a schosh better intake then a Performer..

I installed the 8004 and a remanufactured Q-Jet on the 327 I gave my nephew along with an old, (but still brand new), bought in the eighties from Hollywood Sam's in Detroit, MI, General Kinetics 270/216, 110/?, 454" lift hy- cam..

BTTT, I wish you could scare up a medium journal forged crank and forged flat-top pistons b/c your motor with Harold's cam should be able to see the high side of 7,000/7,500 rpm easy even though she may quit making power above 6500!!! Imho... Yes, the sucker will wrap up there like a good short stroke SB can!!

And I would go with the 300-36 intake and a good old 1850 600cfm or tuned to your motor, 3310- Holley 750 vacuum secondary carb., and I am a Q-Jet guy too so if want to run one just use an adapter on the 300-36 intake..

And your exhaust system should be right in there too!!

Uncle is right about the low end torque so consider his comments and so hopefully you will be installing the 3.73's sooner instead of later along with 26" tall tires!! This way you will gain some low end gear ratio vs 3.55's and 27" tall tires...

Please play with this formula if you want to see how your speed will be affected..

MPH = (RPM x Tire Diameter (in inches))/(Rearend Gear Ratio x 336).

pdq67

This will be for my son's car - a low buck rebuild which only needs to last a couple of years or so. Initially he wanted to bore the block and get new pistons, but now he's realized how much this stuff costs and has decided to spend his money on the heads (which is what I suggested in the first place). That way, if he wants to build a 355 later he can bore the block (or the block that's in my car now) and still use the same heads. His budget isn't very high, and he's going to have over 500 in the cooling and braking systems. The car still needs tires and an interior.

He's pretty set on 255/60R15's (27" tall) for the rear and the 3.73 gears.

Do you think the 256F10 would be a better choice?

May I make a couple observations ?

In the past I have run a couple different 327's.

JMO but I tend to think that the 327 with it's shorter stroke tends to like a bit smaller cam and carb vs the typical 350's.327's love to rev and tend to like some gear.

The 264F-10 would probably be about the largest cam
I would put in it.Back when I had my old 68RS I ran an 097 Duntov solid cam in it and it would grab 6800 RPM in my 3.90 geared Camaro.The 097 is 228/231 @.050 witha short lift of under .400 gross valve lift..Lashed @ .012/.018 hot. I ran a stock 1968 302 intake... basicaly the 300-36 is a copy of the 302 intake.The 302 and the 300-36 are a tall high rise dual plane that is pretty big inside.... After all it was designed to rev to 7200 in those 30-30 Duntov cammed 302's.... But because it is big it really works best above 4000 RPM.

My last 327 had a Crane F218/2933 lobe... .440 lift 218@ .050 lashed at .024 cold.This cam would grab 6000 RPM and do it with a very small carb..A 390 CFM Holley 4bbl... I tried a 600 Edelbrock and a Holley 0-3310 and the little 390 Holley would grab RPM noticably quicker than the larger carbs.I know many people dont belive this but sometimes a mildier combo can really work well.Went absoutly nuts between 4000 - 6000 RPM.

If you run the 300-36 , it is a tall manifold and I'm not positive that with an adapter and a QJet and an Air cleaner if it will all fit under the hood.

With a mechanical cam I have to think you are real close with your idea of something in the 226 to 234 deg @ .050 range couple with a 3.73 gear to get the 6000 - 6500 RPM range.... A 600 to 650 CFM carb would be plenty... Those stock 30-30 Duntov cammed 365 HP 327's only cam with 585 CFM carbs and would rev 6500 RPM easy.

Thanks for all the replies and suggestions. We appreciate it.

Used the CR calculator on the Keith Black site since I have the intake valve closing spec 42 ABDC @ .050, and it DCRs to a shade over 8.5. Is that a bit high?

You have to use the advertised intake closing spec (seat to seat). @ .050" the valve is still open and the DCR is bogus. The DCR will be lower with advertised.

Thanks Pat. I was going to use your SCR/DCR calculator, but I just got the cam specs last night on the Performance forum and the timing is for @ .020" lift and @ .050" lift. Seems like the advertised 264 duration is also @ .020". It looks like it falls in between Isky's Z-20 and Z-25.

I am a Q-Jet guy too so if want to run one just use an adapter on the 300-36 intake..Consider a Performer RPM Q-jet manifold (#7104). It is designed for a spreadbore. That is what I purchased for my 327.

My engine will be virtually identical to yours, but I am looking at the 256F10 or comp 270S. The 264F cam seems a bit big to me, unless you have a car with a manual trans, or a 3000+ converter and 3.73-4.10 gears. Just my opinion...

8.5 DCR is a bit on the high side for a street car. I'd look to lower it to between 8.2 and 8.3. You can use 8.5 but the engine will be on the very edge of detonation.

I know Harold's cams are a little different but I get 56º intake closing (264 Adv Dur, 110 LSA, 6º advance). At 4º advance, 58º. That is a big difference from 42º.

novadude,
I had considered the 256F10, but thought that it would yeild a higher DCR than the 264F10 because the intake valve would be closing sooner. I could be wrong, but I think the smaller of these two cams, the 256F, would be more detonation prone with a SCR of 9.7 (guestimated CR of 327 w/ 64cc heads) or more. To be honest, I'm going to have to cipher on this DCR deal with more accuracy - either I'm overlooking something or it's going to be borderline with the 9.7 CR and the 264F10.

I ran a 327 +.030 with 64cc heads, a .040 quench, and 6cc pistons throught the DCR calculator. SCR comes out at 9.66. With the 264 cam (6º advance, IC @ 56º) the DCR is around 8.18. This is excellent and the engine will make plenty of power. With this DCR it should make about as much low end torque as a 327 is capable of.

The 256 cam is too small for the CR you have with 6º advance. With 4º the DCR is 8.28 but Harold likes his cams at 6º so the 264 is the better choice.

Thanks for going to the trouble to do that, Pat.

Where are you getting the IC @ 56* from? The 264 duration is @ .020", so I had no way of knowing off/on seat timing. I'll take your word that the cam will work, just curious as to where the IC came from. Maybe I'm misunderstanding the specs. No big deal - I don't need to understand, just need it to work.

Glenn,

This is doing it the hard way..

Take a degreed circle and find the LCA point of the 264 cam you are looking at, say 110 ATDC that is put in the motor at say, 106, (or 4 degrees advanced!)..

Now take half of the advertised duration and count on around the circle from 106 until you hit 132 degrees.

Then you express the 132 degrees as 58 degrees ABDC!!

Do you follow me??

This is why it's so important to know the intake valve's closing number!!!

pdq67

.020" is to allow for lash. This is a solid cam, right? Seat timing for a solid cam is calculated using the formula "lash/rocker_ratio+.004". This gives the tappet lift at which the valve starts to rise off the seat. For a SBC (actually any engine) with 1.5 rockers, .020" is only correct if the lash is .024". At other lashes it is incorrect. However, by convention I guess, most mfgs use .020" for wide lash cams. It is usually close enough for DCR calcs unless you are right at the edge.

The standard formula for calculating the intake closing is "(Intake_adv_dur/2)-(180-Intake_Lobe_Centerline)". Harold's cams are "unsymmetrical". That is, they have longer closing ramps than opening ramps. The above formula works with most cams but may be off a bit with Harold's cams (I don't know how much). Which probably explains why he likes his cams installed with 6º advance rather than the usually 4º.

Hey PDQ, you posted while I was typing. That method works. A bit cumbersome, though, if you don't have the cam setting in the block smile.gif . That is the best way to confirm everything. I consider checking the seat and .050" timings as part of degreeing a cam.

Thanks for the thorough explanations. Looks like it'll be a good cam for this engine.

Yes, the unsymetrical lobes don't show up very good using D2K..

I wish D2K could handle lash, duration at .050" and duration at .200" timing events if we could just get the information from the manufacturers cam cats.

We would get a better cam curve equation for the iterative process to use to calculate hp and t.. Imho...

Oh well use what we got b/c it IS just the trends that is useful to judge part changes..

pdq67

Pat,

What head gasket bore size did you use in your DCR calc?

Thanks,
John

John, I used .015"x4.100" for the gasket and .025" for the deck. Compression will drop a bit with a (.039 or .041)x4.166" and a zero deck.

Glenn, I don't know if I'm telling you something you already know but... When you install the cam, the advance marks on the timing set are in addition to any advance built into the cam. That is, given a cam with 4º built in it, the "zero advance" marks on the gears will set the cam's advance at 4º advance (4+0). The +4 marks will set the cam at 8º advance (4+4). The -4 mark will result in 0º advance (4-4). It's easy to get confused about the marks on the timing set and where the cam is installed. I hope this makes sense smile.gif .

Makes sense... I think I used 4.166 and 0.028 for the GM composition gasket I am using, and came up with ~9.3x:1 w/ .025" deck.

I'm not sure but I think the .028 gasket is 4.100.

Was in a hurry when I last posted, but I'd like to thank everyone who participated and gave advice/opinions.

We've decided to bore it - I have a good feeling about this.

Pat, about this degreeing, am I to understand that if I ask Harold to make it 6* advanced and install it straight up according to everything else, it'll come out advanced 6*, which is what Harold recommends? (I'll ask him when I call him.)

That would be correct**. The problem is Lunati cams are ground with 4º advance. To get 6º you'd need a bushing in the cam gear. Not hard to do but needed for 6º. So, with a 2º bushing and a cam with 4 degrees in it, you use the zero advance timing set marks and install the bushing to get the extra 2º. On the other hand, you could use a Cloyes Hex-A-Just timing set (infinitly adjustable) and set the timing that way. They're about a hundred bucks, though.

**Be careful with the term "straight up". Technically, the term means the LSA and ICL are the same, regardless what timing set marks are used. That is a 110 LSA is installed at 110 ICL. No advance whatsoever. You'll notice I was careful to always say if I was referring to the marks on the timing set or the position of the cam. This term is the source of a lot of confusion when talking cam installation.

Originally posted by Pat Kelley:
The problem is Lunati cams are ground with 4º advance. To get 6º you'd need a bushing in the cam gear. Is that true of Lunati/Lunati cams AND Lunati/Ultradyne-design cams Harold brought with him?

I have one of the last Ultradyne cams made and Harold told that if I wanted 25-40 "free" HP I should install it 6 degrees advanced. Now I'm unsure if I should go 6 or just 2 to get the total of 6 I need.

AFAIK, yes both Lunati/Lunati and Lunati/Harold's cams are this way. He said, and I don't know if this has change recently, that the cores Lunati uses are made with 4º advance. UltraDyne had their cores drilled for 2º advance.

If you have a true Ultradyne, it should have 2º in it (best to ask Harold about this). In that case, you install it using the "+4" marks on the timing set to get 6º.

Good point about the term "straight-up" Pat!!

I always try to say LCA/ICA and I will say install it as is straight up if the timing set has a 4 degrees advanced, none and 4 degrees retarded and then I have to remember just what the cam is made to end up being installed at, at the "none" mark which would put a stock CC cam at 4 degrees advanced since that's the way they make them unless you order different..

DARN confusing isn't it??

pdq67!!

you guys might be able to help out over in this this thread (http://www.chevelles.com/forum/ultimatebb.php?ubb=get_topic;f=4;t=021265) over in Perf. Looks like the guy might have one of the older timing sets that move the cam 4 camshaft degrees, eight crankshaft degrees. I've replied to him, but it be good if somebody looked too. The thread title is something like "can cam gears be this far off?" clickable link above.

And yes, I agree, you have to be very careful about exact words used when talking about this stuff. I always thought straight up meant the LSA (lobe separation angle) and ICL (intake centerline) were the same. I discovered not all people think that same way. :(

Tom