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Hello, I am new to this forum and I'm looking for help with a cutom hyd roller cam for my 351c. I have ready many posts on other forums written by George P. and Dan Jones on camshafts. There was one particular series of tests done by Dan using a hyd roller cam with many different heads and intakes on a non stroked 351c. It was a custom ground Reed cam, but the lobe seperation was only 107 and ground on a 104 center. The results were very good but there seemed to be a later correction that was suggesting a wider lobe seperation angle. The cam specs were 228/232 with .588 lift and 68 deg of overlap. Can anyone help me with this?
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The Reed cam you described is a rough idling cam with a soft bottom end. It'll have limited top end unless the exhaust system has no back-pressure. A free breathing exhaust will also improve the low rpm a bit. Its not a cam I'd ever use in a street engine. This evaluation would have been obvious to any hot rodding enthusiast in the 1960s. So no ... I'm not a guru for having determined this. I'm just willing to admit I'm a bit of a throwback.

I can offer humble help (in humility) if a high performing street cam or sports car cam is your desire. The cam will have 112 degrees to 114 degrees LSA. I know the cams work, they've been working since the 1960s. Others have discovered they work too. I can explain why they work if necessary. But honestly, I'm not into "this guy verses that guy", I don't need to prove anything. Other voices on the internet speak to people with different goals than I do. What are your goals?
Thanks for the reply George. I have read many of your posts. I'm looking for 450 hp. In a real street combo. I have a non stroked 351c with 10.5 cr and Chi EM185 heads and tall single plane intake. I know there are many cams out there that will make the power but I want it to run around town in traffic when I need to. I definitely want a hydraulic roller, I already have everything except the cam itself.
Well, I guess not everything. I have the link bar style lifters for a non reduced base circle cam, and beehive springs for .600 lift, but I don't have the pushrods yet. I will have to check the length I need first. I also have Yella Tera 1.73 roller rockers. I have spent the money on high quality parts like you have suggested in other posts but I know how important the cam is to the rest of the combo. Thanks again George
I am very happy with my hydraulic roller from Bullet Cams. I posted up the cam specs in my thread on my car (5357).

I also got custom length pushrods from Smith Brothers. Fast service. My engine builder gave me the required length, and I had the pushrods to him two days later.

Here's a link to my cam data. Hope to have some dyno numbers in a couple weeks.

They are down towards the bottom of the page.

I agonized over the choice of cam for weeks - but I am happy I followed this recommendation. Good idle, good vacuum, and it runs GREAT - pulls hard from 3000 - 6000 Rpm.

Engine specs are on page 1 of the thread.

Last edited by rocky
beehive springs for .600 lift

Who's beehive springs do you have? I had beehive springs for my 383C build and broke one, which drops the valve into the cylinder - add another $3,000 to the rebuild cost to do it again re-using the reusable parts. My beehive springs were rated for .600" lift and my cam only had .588" lift, but several springs were out of spec (I trusted the mfgr's specs and didn't measure each spring for height at coil bind) and suffered coil bind, which is why one of them broke at 987 miles following the rebuild.

Be sure to check everything.
There are several specs I use that mimic the Ford street cams such as the Cobra Jet cam, the single pattern Boss cam, the Motorsport A341 cam, and my own "ultra-Boss" spec. There are subtle differences in intake duration, lobe centerlines, and overlap between each one. The spec I like to work with best is this one, based on the M code camshaft:

Based on Ford D0AZ-6250-C
M code i.e. 1970-1971 351 4V
112° ATDC intake lobe mathematic centerline
117° BTDC exhaust lobe mathematic centerline
Duration (and valve timing) specs may vary +/- 2°
But do not alter the lobe centerlines

276°/286° advertised duration (281° average)
224°/234° duration at 0.050"

Duration at 0.050” is based on 52° hyd. intensity
Therefore overlap at 0.050” = 0°
Lobe separation angle = 114.5°

0.328"/0.328" recommended lobe lift (hyd. tappet)
0.567”/0.567” theoretical valve lift (1.73:1 ratio)
0.550”/0.550” factual valve lift (1.70:1 ratio)

EVO = 80° BBDC
IVO = 26° BTDC
Overlap = 52°
EVC = 26° ATDC
IVC = 70° ABDC

I'm getting ready to step out for a while. I can pick a set of lobes from the Bullet Cams catalog later this evening, there are plenty of good hydraulic roller cam lobes to choose from.
Last edited by George P

Originally posted by 4V & Proud:

I'm worried for you that the 185 ports will not support your modest goal...

also not sure a traditional Cleveland cam would be optimal, George ?

The 185 ports are an extreme take on the CHI philosophy, they boost velocity by shrinking the ports, and restore some of the airflow and top-end performance that was lost by raising the ports. The roofs of the 185 intake ports are at least 1/8" higher than the roofs the 4V intake ports. I believe the heads were originally designed at the request of Dave Storlein. I would imagine the small cross-section intake ports are tuned to make peak horsepower at about 5000 rpm out of the box, and to raise the rpm at which peak horsepower occurs requires stretching the camshaft's intake duration, this of course is not necessary with the 4V Cleveland heads (which are tuned for peak horsepower at about 6000 rpm), but it is quite normal for other heads like a 2V Cleveland head or a SBF head.

The cam spec I mentioned will "work" but the engine will tend to make peak horsepower a bit lower than it would with 4V heads, about 5500 rpm. If Greg would prefer to have horsepower peak at a higher rpm, there are a couple of other specs I would choose to use. Greg just let me know.
So here's the spec based on the lobes I've chosen:

Ford 351 Cleveland hydraulic roller street cam
Grinder: Bullet Cams
Intake #HR275/330 (Symmetric lobe)
Exhaust #HR288/335 (Asymmetric lobe)
112° ATDC intake lobe mathematic centerline
117° BTDC exhaust lobe mathematic centerline

275°/288° advertised duration (281.5° average)
224°/234° duration at 0.050"

51°/54° hyd. intensity
Overlap at 0.050” = -4°
Lobe separation angle = 114.5°

0.330"/0.335" lobe lift
0.571”/0.580” theoretical valve lift (1.73:1 ratio)
0.553”/0.561” factual valve lift [(lobe lift - 0.005) x 1.70]

EVO = 81° BBDC
IVO = 25.5° BTDC
Overlap = 52.5°
EVC = 27° ATDC
IVC = 69.5° ABDC

How's that?
Thanks again everyone for your responses. To answer a couple questions: I checked and I bought the Pac 1520 beehives for a BBC and they are designed to work for up to .650 lift. I may have to have the heads machined to get correct installed hight. Maybe I shouldn't bother with beehives? I wanted my cam to peak around 6k rpm and shift around 6,300 or so. The car is a unique motorcars cobra replica that weighs 2400lbs. I have a billet aluminum flywheel and tremec 5 speed tranny. I want it rev quickly, which it should. And pull strong from 3 to 6k. But I want to drive it around town and be able to cruise at 2500rpm. I have to say that the pantera is my favorite car. My Dad had one that was done by Hall pantera in California, and it was an amazing machine in every way. That car is why I'm building this 351c in the first place.

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