custom ground cam specs....advice

jetski247

jetski247

Member
custom ground cam specs....advice/guru

just want to make sure before i do yet another cam swap that im not missing something by not running this cam. these specs were ground for my collection of parts for a test build that was suppose to be lots of torque with good mid range. called camshaft research and they ground me this for $350 which was very resonable being that most roller cams arent much cheaper, anyway, there are the specs......and yes, i went over with them what it was going in and what i wanted, and these are the parts that will be used........you get the idea. was ground for the larger valve 40's i have and 1.72s, edelbrock upper/lower and shorties, speed density since my baumanator quit working for my maf swap but it did run much better on the maf.

i ran this cam but could not get it to idle, gave me the exact same issues as with the 5.0 ho cam. i saw no performance increase over stock cam/e7's but may have had other issues going on when i ran it but it did run, even with 112* lobe seperation.

so im needing help in the right direction, advance the 5.oho cam or put this back in and give it another try.

specs are:
gross valve lift
IN .480 EX .480
ADVERTISED IN 272 EX 280
DURATION @ .050
IN 208 EX 213

VALVE TIMING @ 108 ICL
OPEN..........CLOSE
INTAKE BTDC -4 ABDC 32
EXHAUST BBDC 42 ATDC -9
LOBE LIFT IN .300 EX .300
LOBE SEPERATION 112*

They were originally going with 110* lobe seperation but told them SD and then they ground this.

and ive got several videos of 0-60, 20, 50mph take offs with this cam on stock speed density on supermotors but can't get it to load them. i shoulda put em on youtube i guess. i can't say it was any gains or loss, i just didn't notice any differance but again, coulda been other issues i found out later, thanks to you guys. this is outa the f150/bronco's realm of specialty.
 
Last edited:
cam research has an excellent reputation for building ford engines. that mild cam has very reasonable duration for oem SD and also has negative (-) 13 degrees of overlap which should be fine also. the 112 LSA sounds ok as well because of the mild (for SD) -13 deg overlap. most places and people say 114 deg as a minimum LSA, but the overlap is pretty much the more important spec generally speaking (within limits), imho. i also think your problem(s) is elsewhere. this cam and the 5.0 HO should work fine. just my 2 cents.
 
I think you're right. My issues are other things for sure, and both do work.

What does the less lobe seperati on do?
And it took a cam swap for me to figure that out.
 
Last edited:
as far as an oem SD application, generally speaking, less LSA means more overlap and lower vacuum. i also think more overlap can possibly allow pressure pulses to travel up the intake port (affecting the MAP sensor) and give the oem SD a hard time idling properly.
 
bobwhite said:
cam research has an excellent reputation for building ford engines. that mild cam has very reasonable duration for oem SD and also has negative (-) 13 degrees of overlap which should be fine also. the 112 LSA sounds ok as well because of the mild (for SD) -13 deg overlap. most places and people say 114 deg as a minimum LSA, but the overlap is pretty much the more important spec generally speaking (within limits), imho. i also think your problem(s) is elsewhere. this cam and the 5.0 HO should work fine. just my 2 cents.
Click to expand...

He's mixing the specs. The opening and closing numbers he posted are at 0.050, not on the seat. That cam has 52 degrees of overlap.
 
oilwell1415 said:
He's mixing the specs. The opening and closing numbers he posted are at 0.050, not on the seat. That cam has 52 degrees of overlap.
Click to expand...


is that 52 deg "advertised duration" @ .006" or what? i always use .050" cam specs. -13 deg overlap @ .050" is reasonable for oem SD. the stock gen 1 cam has about - 24 deg overlap and the 5.0 HO roller has about -20 deg overlap. cam i have has -2 or -3 deg OL iirc. if my cam had -13 deg OL my occasional slight stutter/shake would probably be non-existent.
 
My truck has an Comp Cams XE264HR-12 in it when I got it. Ran perfectly fine for the first 5 years. Have been chasing a stalling problem the last few months. Going to fix an exhaust leak and reset the idle and tps this weekend. But like I said the truck ran perfectly fine with this cam and no tune for 5 years.
 
Just as an update, put the custom ground cam in and 1.7s and shimmed everything, fired up and will test run)drive today. Hooking up an efan due to the body lift/cooling issue then drive it. Idle needs some tweaking, I'm sitting at about 17 at idle. But it started surging so I had to adjust and then reset TPS after the adj.
 
No, still has a surge. Been driving it every day. Had to fix egr but still surges, clean out fuel tank and fuel pump, inline filter element was broken allowing trash to the injectors. Swapped two different throttle body s, iacs, TPS, setting them to .99 after it idles ok.

When in park, the idle ramps up and down about two or three hundred RPM......... sometimes......... sometimes it hangs at about 1k. When cruising and I let off the throttle, you can watch the tach go from 1200, down to 700, back up to 1200 and do it several times.

When I first installed this cam, it idled smooth as silk but would die in gear, idle was set with butterfly's closed and just the iac controlling the engine. The only issue was in gear, instant death.
 
when replacing the egr, the old one is so that the sensor on top does not get actuated until vacuum is applied. the fleabay one i purchased has a nipple inside that pushes the rod on the sensor up about a quarter inch or so, not sure if that is effecting the way it runs but...........torque does seem to be much better from off idle all the way through the power band with the egr somewhat working or either the computer (speed density) if fine tuning its adjustements.

there is a cel i need to check but kids have been sick and ive been trapped inside for the last couple days. i was going to install the 1/2" phenolic spacer for the edelbrock intake but realized my egr tube will need to be expanded somehow in order the reach the extra distance of the spacer, something i didn't account for when i purchased it but it was on sale for $20 or so.
 
From past experience, I can definitely tell you that an EGR that's not working 100% will cause all kinds of unhappiness, both from the vacuum leak and the elevated IAT readings.
 
oilwell1415 said:
He's mixing the specs. The opening and closing numbers he posted are at 0.050, not on the seat. That cam has 52 degrees of overlap.
Click to expand...

and if "HE" means me, then no, im not mixing the cam specs. those are directly from the cam sheet exactly as its printed.
 
just as an update, been driving the truck just to drive it because im tired of working on it and it just sitting in the driveway waiting on some sort of part that may help.

the ONLY issue ive has is an intermittent engine stall when switching from D to R or vise versa with the A/C on when getting out of a parking spot or something like that. ive done so many tb resets where i think its fixed, it will do great for several days then just die 3 or 4 times in one day. if i get it to where it won't die, the neutral idle is around 1k and when coasting to a stop, the idle will fluctuated from 1200 to 800 and kinda jump up and down like a vacuum leak and im TIRED of looking and triple checking for vacuum leaks lol

I drove the truck on several 3hr drives down to the beach fishing, where the truck never turned off for several hours with no issues. gets about 8-11 mpg in town and 12-16 on the hwy. my speedo is a little off due to the larger tires but gps shows its pretty close. best mph was a bout 15.5, fully loaded on the way to the beach, babying it the whole way staying around 2k and no faster than 65. remember its go 1 ton axles, a lift and 200k+ on the engine and 350k+ on the e40d, even though i went through the engine i took from an e150 van with around 200k since my gf blew up my last one which was the original. and the original pistons looked amazing for that high of mileage and i build engines for a living.......well, use to.
 
I've picked up a '94 Lightning that has somewhere around 270K miles on it (can't be sure, the cluster has been replaced). I've been fighting with an intermittent surging idle, rough running, down on power, etc situation with it since I got it. I worked through all the vacuum lines, changed a few sensors, etc, and every time I thought I'd found the problem, but it kept coming back.

I was getting an inconsistent CEL light, though, and that's one difference, and it was for "lean at part throttle." I was also getting terrible mileage. Anyway, I pulled out the computer this past weekend and opened it up to take a look. Three of the capacitors had failed. I put a computer I had in storage in it, and it's running like new.

Just something you might take a look at one afternoon when you're bored.
 
i think i had this one rebuilt but it may have been my maf a9p due to the 3 capacitors. but yes, they are prob bad if i havent rebuilt it yet but i'll have to pull it apart and check.

when i was running maf, it was running exactly like yours, then found the 3 bad capacitors, had it rebuilt but it ran the same unfortunately. then i switched back to as much stock or near stock as i could just to drive the ham thing.
 
im going to try and run the 1.6's instead of the 1.72's since the extra overlap, perhaps it will speed up velocity just slightly as well as a slight bump in vacuum? to try and solve the very very minimum running issues, again, this cam in this truck runs better and stronger that a lot of other trucks with this age for sure.

again, the only issue is an idle in park that goes to 1k sometimes (could be a vacuum leak, gasket on the intake manifold sucking in engine vacuum from underneath slightly) who knows. when coming up to a stop, the tach just jumps up and down from 1200 to 800 every second or so. like a vacuum leak that the computer is trying to compensate for but just can't get right.

im also going to go back to the stock throttle body to kinda choke things down instead of the twin 56 which i think may be too big for the large valve ported gt40's im running? just some things im going to try to see if i can perfec3t all running conditions.

and remember this is an f150 with the twin throttle body set up, not the single mustang style which has a pita tps sensor to get to and adjust.
 
Thankfully I've been able to move on from the weird running problems and start to battle all the other gremlins that live in a 27 year old vehicle! Hopefully you'll get yours sorted, too. I wish I had more to offer!
 
My truck idled better with the TPS lower than .99. The idle would be fine then suddenly hang at about 1000 rpm. Lowered it to .94 and problem is gone.
 
I haven't tried to lower tps voltage but tried to raise it to 1.02 which seemed a little peppier but idle would still hang.
I have to put it at about 900 so it won't die under a load such as in gear at a light with the AC on. Everything thing else seems fine and the custom ground cam def makes a noticable difference through the rpm range other than idle.

The stock throttle body set up the throttle butterflies were completely closed in the truck idled just with the IAC. With this custom cam I have to crack the throttle butterflies to get it to idle unlike the stock throttle body setup with the stock cam. I was thinking about drilling an idle hole port in order to close the throttle butterflies and keep drilling the whole larger until idle is happy I have a stock throttle body that I can butcher to run the experiment so I don't hack up one of my BBK throttle bodies. vacuum with the custom Cam and all the mods done to the truck sits at 18" while idling in park. In gear the truck idles at about 15" vaccum on the 112 deg cam
 
You must log in or register to reply here.
Back
Top