Guys, I'm looking at two cams(open to suggestions) for the 509 I will begin building after the first of the new year. The goal is low 11's in my 3900 full bodied 70 Malibu.
No definate plans as of yet but, I do have most of the parts together...
4.500 Bowtie block
4.00 GM forged crank
7/16 dimple rods
Ross custom forged pistons, 11:1 in 119 cc chambers
Worked GM #049 ovals with 2.19/1.88 valves(wishing for the Brodix RaceRites from Mike but, budget is tight!)
Holley 950 HP
I have a choice of Performer RPM AirGap or Weiand Team G single plane
3200-3500 stall in a worked Turbo 350
1 7/8 Hedman coated hedders
3" in/out UltraFlow mufflers w/turndowns

...the two solid roller cams are...
#1)Harolds' 502A4LUN 256/264 duration, .660/.660 lift on a 110 LSA or...
#2)Howards Cams 248/254 duration, .665/.679 lift on a 110 LSA.

Obviously, Harold's cam works alittle higher in the powerband but, do I need to go that high with my 4.10 gears 278/60/15 BFGoodrich Drag Radials(slicks to come)? Also in consideration is the fact that I would like to drive the car on the street and have just enough vacuum for power brakes would be nice. Spring pressures look to be about 600lbs open and 225lbs closed so, I will definately be getting the Isky Redzone lifters.
Any and all opinions appreciated.

SILVERSS454,

Around 1994, June issue, I believe, PHR had a Red/Black 70 1/2 Camaro on the front cover. It had a 509 in it, close on compression, 3700 lbs, 3.9 rear gear, 3000 SS converter, and the cam that became the Lunati 502A4LUN. The owner would drive it 125 miles to the strip, run 11.10's on engine, and drive it back.
I do not know how much vacuum he had, and would think you would need a vacuum pump, to be safe.
His car may have gone faster, I do not know his final times.
The 502A3/502A4 have always given multi-year street life, and your springs make them a 7500-RPM cam.....

UDHarold

I know Harold and the UD/Lunati cams only from here on TC, and dont doubt for one minute their performance and reliability, but I have a Howard's cam, very close to what you quote...mine is custom grind, but about the same duration, little more lift, and 108 LSA...it is awesome in performance, and vacuum isnt too bad either...only have power brakes, but it was no worse that other cams I have had. I run it in a 460, and will be using it in my stroker engine next season. I highly recommend any of Howard's Cams products. John

Harold, thanks for your reply. I was hoping to go without the vacuum pump so, I may have to reconsider the 502A4LUN cam, maybe step down one notch to the 502A3.
John, can you give me some additional info on your cam and engine setup? Also would like to hear about the performance you are getting from your combo. Thanks much.

I'm putting that Harold cam in my new 491. I fully expect it to have vacuum for power brakes on a 110 LSA. However I run EFI with programmable timing control. I will run 28-32 degrees of timing at idle. This will help idle vaccum A LOT.

If you run 12 degrees or whatever of timing at idle, you will have a lot less vacuum.

I suggest recurving your distributor and limiting advance (or getting EFI smile.gif )

I've run the 502A4 cam for the past year.
Very pleased with the results, so far. graemlins/thumbsup.gif