I have always gone with flat tappet cams, but having my motor apart, I was considering a hydraulic roller instead. Other than costing a fortune and needing no break-in and less rocker clatter, are there any things that make it any more or less of a performance cam? This is going in a Mark IV motor.

Thanks,

Mike

Mike what CI motor is it and what is your intended use? A hydraulic roller, IMHO, is an excellent upgrade for power and ease of use.
I would highly recomend giving UDHarold a call, other than that, ask cammotion for a recomendation, or other cam manufacturers. I know manufac. busting isn't allowed here, but my luck so far with cams from a major cam manufacturer have been less than spectacular.
If its a 454 and you don't mind a little grumble and some lift, can afford full roller rockers and some forged 9.6-10:1 slugs, I'd ask harold to dig up his UD HR4 profile..
Killer cam.
I went with a solid roller this time over my hydraulic roller, and I was coerced by my engine builder to use a major cam maker cam versus a similar UDLunatiHarold cam that I was greatly in favor of. I know I would have gotten more torque out of that puppy than with the major cam manufac grind, and aside from that I think the cam is too big and killed off low end torque. It just doesn't have that light the tires on fire feeling anymore.
Sorry-- I always talk about myself.
Give yourself a new twist on life, they make some excellent hydraulic rollers now that require almost no maint. after setup (if any), make excellent power if correctly picked.
I did a bucketload of research for the right cam for my 10:1 454 (462 really), and I would be happy to share any info I got.
Go with a roller. No trashed lobes, a good set of hyd. roller lifters is two or three hundred extra, and the cam about 150 more, but well worth it. IMHO.

Matt

Awell desinged flat tappet will make more power than an analougous HR I bet, but they will certainly make more power than a hyd flat tappet. Not the cam I pick to rip to 7000 though, but a great 6000 rpm cam. Plan to use an HR in a 496 coming up.

Sorry Gene I just have to beg to differ here.. I know your older and far more experienced, but the ramp profiles they can use with a hyd. roller for an under 6k motor I'd say outweigh any of the benefits of the solid.
I love the feel of my solid-- it runs so smooth and its great, but IMHO your going to get a ton more area under the curve with an HR than with a solid flat. The only drawback I can see with HR's is revability, people do rev them, but I've seen and heard valve float and all out valve failure on hyd rollers on an engine dyno.
A well picked HD roller, I'd say, will outperform a solid flat, up to a certain degree. When you get to the really big stuff, then I think the solids take their advtange again.
But for a HR.. say.. 292 @ .006, 242-244 @ .050, .600 lift, in a 454, you'd have a rockin and rollin street 454.
I was intially planning a cammotion 292/296 242/248 .629 HR because harold was in transisition for my cam swap.
His HR4 by far felt like the fastest cam I've had in my car, it was def faster than the comp cams "estimate copy" of it, but it died at 5.8k from valve float. Obviously I have not run my new solid roller at the track yet, which in theory picked me up about 60hp @ 6000rpm, but I think I lost enough low end I don't know if the trade was worth it. (this is not solid roller cam specific, this is bigger is better syndrome), I know because I can almost launch the car on the street a little easier than with my old small grinds.
Just my .02.
But solid flats, save for maybe the 288/296, IMHO (this is not a personal attack on anyone, general comments only), are for a generation that grew up with solid flats.

Matt

Thanks for the reponses. Drivetrain/motor: 40 over 454, 10-10.5:1 cast pistons, edelbrock ovals, 1 3/4" headers, roller rockers, 3.73 gears, 10" converter, turbo 400...the usual "overkill for a car that won't see the track" type stuff.

Mike

Mike..

In all honesty, if your gonna keep it under 6k and not out for max performance, try a HR out.. maybe you will hate it, and then by proxy me.. I'm not a mechanic, but they work fine. an UD HR4 would be a sweet sreet with tiny bit of strip cam in that car, a little bit bigger UD or cammotion would be great street/strip cam.

Please, what's the spec's on Harold's old UD HR4 cam??

Just to file it away, that's all sorta deal...

Thanks in advance..

pdq67

we have run an almost exact copy of your motor. all steel 81 monte carlo(except for hood). a 9.5-1 454 with stock valve size 049 heads. performer rpm intake topped by a edelbrock stock 750 carb and hei ignition. same small tube headers. comp cam hydraulic roller .575 lift. 10" B&M converter with 3.73 gears and 26" tall slicks. runs 11.8-11.90&111 mph. nice lope but very streetable. i'm sure you could duplicate or surpass this performance with a flat tappet. if this is more of a street car i would save my $. you can make more than enough torque with what you have for a street car. mike

Pd,

It was nothing special-- or so it seemed. It was 296 @ .006 233 @ .050 .621 lift.. very old cam design. UD HR4 was what its grind was. Very old design according to Harold, but a good performer. I'd think it would be an excellent cam for a 454 with iron heads, 9.6:1, iron oval ports, bigger valves, mild headers, a 750DP, decent ignition and a turbo 400/maybe turbo 350 and street gears. Lumpity idle and very odd loud unique exhaust tone. It would def be a 500/500 engine dyno combo IMHO. I don't know what kind of cam Chris Corwell (hope I got your name right) is using in his ride, but I think this would be an interesting cam for him.
When I was rebuilding the engine, I was dying to see what the thing would make with 10.14:1 CR, but things didn't go right.
When I redo my LS5 block I think the cam is too big to try to get away with calling it original "LS5 cam", but I'm gonna get an UD in there somehow..

But it made killer torque-- even in my huge rect port heads, the torque numbers were off the charts, and hp was right up there too until about 5700 rpm.
Great for a mid size grunt motor. I have a personal attachment to this cam, so I may be over stating it here, but my dyno sheet from 1996 says 574 ft-lbs @ 3600 and 564 hp @ 5500. The thing had a very unique mean sound to it too.
I may be remembering it better than it was, but I loved that cam and would still be running it probably if UD wasn't in a transition period when I rebuilt my motor last year.
Just for an idea, in my 4020lb car, the first time I had ever been to the track, on a sunny 80 degree day at NED, it ran a low low 12.7 @ 114.high mph. I have the slip in my photo album outside, with a converter so tight it pulled through the brakes, I had't gotten my precision industries (I still wonder if that brand was a mistake) 3400 stall.
This was through 3.31's and p245/45R15 BFG comp T/A regular street radials.. my 60' was like 2.225 or worse..
Its not blazing saddles, but for a 9.6:1 460 with rect port heads with a first time driver, it pushed more mph than any cam I have owned since.
Even when I bumped the CR to 10.14:1 and had a large cam company replicate the cam, I lost about 5 hp peak and 27 ft-lbs of torque from 4000 to 5200.

So yeah-- take what I say with a grain of salt, but 99.9% of it is true. I think someone else on this board runs the same cam, BigRedL78 maybe, I don't know how well it does in his combo.
matt

Thanks MM,

I saved the info with Harold's old UD cam list I have.

pdq67

Originally posted by MadMarv:
Pd,


I think someone else on this board runs the same cam, BigRedL78 maybe, I don't know how well it does in his combo.
matt I do have that cam in BigRed.

233@.050 .625/.625 single pattern 109 sep.
Rpm wise I shift 1-2 @ 5800 or so 2-3 6000-6200.
I have gone 6500 rpm a couple times, but the performance didn`t warrant going up that high.

I would actually like to try differant gears like 3.55 or maybe 3.73`s.
I`m not sure what`s available for my 4-series carrier.
I think a hyd roller would work just fine.

Thanks again for the responses. I am running a lunati solid grind right now, never liked hydraulic cams. I am just not that familiar with them. I'll just stick with what I've got since I don't need to flush 7 bills down the toilet for nothing.

Mike

That's about the size of it!

I would actually like to try differant gears like 3.55 or maybe 3.73`s.
I`m not sure what`s available for my 4-series carrier.
Hey BigRed,

I believe you can get a 3.73 in a 4-series carrier. I think that is the lowest (numerically) you can go with that carrier.

For everyone....

The UHR4 is being recut. I sent it off this morning(6:55 AM CST)to the master-maker.
The new UHR4 is IDENTICAL under .060", both opening and closing sides. It's gained a degree or 2 at .200, and is .3683" lobe lift, for .626" valve lift with 1.7:1 rockers.
It's the start of a new family for marine use, all with .626" valve lift.
.050s--233,241,249,255,263. Mostly on 112 or 114 LSA. These ramps have run for 550 hours under load at Mercury Marine.

Give us about 2 weeks.....

UDHarold