ME Leigh

I was just looking through the comp catalog, and noticed that they had some XE solid lifter cams. Now i want to swap in a XE262 into my 305 this winter and was wondering hey.

The XE262H is 262/270, 218/224, .462/.469 110LSA
XS262S is 262/268, 224/230 .477/.488 110LSA

According to DD2000 the solid cam make alot more power. Has anybody run one of these? Any opinions about running one of these on the street? Thoughts....?

Stekman

Did you tell it to run solid? I think that the manual (who reads those?) says to only select solid if it is a solid roller? Something like that??

Other than that...they sound cool! I say go for it Leigh.

*edit* looking back at the numbers you posted, it does SORT OF make sense. Comparing the advertised and .050" durations, the solid appears to have the slightly quicker ramp rates with a higher peak point. Opens the valve faster and to a higher point, thus, more power.

ME Leigh

Yes those solid numbers are with "solid cam" selected. I've read the manual before but can't remember what it said. I guess its time to read it again.

AJ_92RS

One thing that's kinda tricky when comparing a solid to a hyd cam is when using .050".

A hyd lifter only takes up ~.006" of slack (IIRC) which is why you can use a solid lifter when indexing (aka "degreeing") a cam.

When indexing a solid cam, you're measuring .050" of lifter rise, but that isn't .050" x rocker ratio (which would equal .075" with 1.5 rocker) of valve lift. As with most solid cams, ~.025" of valve lash is present. So while the lifter comes up .050", (I'm too lazy to do the actual math right now , the valve doesn't open .075". It only opens (for simplicity's sake) .050".

So a hyd cam with 218* duration @ .050" will have a longer duration that the actual valve is open, while a solid cam with 218* @ .050" won't.

Make any sense?

I don't know if DD2000 takes this into consideration. It's been a while since I've read the instructions as well. I would assume it does (along with other factors), which is why it shows more low RPM torque than a hyd.

Looks like you'll have to break the "guy rule" and read the manual.

David Vizard goes into more detail about this in his valve train/camshaft book, but I'm at work right now and don't have it here.

ME Leigh

I'm not sure about DD2000 and the valve lash, but i know what your talking about.

I just change the original graph, i had a .050 duration graph up there, now its seat-seat still set a s hyd and sld respectively.

I read(manual): 0.050-inch LIFTER rise for both intake and exhaust.
This measurement technique is based on the movement of the cam follower
(lifter) rather than the valve.

The 0.050-inch lifter rise cam timing
method measures valve timing when the
lifter has risen 0.050-inch off of the base
circle of the cam. In the setup pictured
here, the dial indicator is positioned on
an intake lifter; the 0.050-inch valve
timing point can now be read directly off
of the degree wheel attached to the
crankshaft. Timing specs measured
using this method are not meant to
approximate the actual valve opening
and closing points, instead their purpose
is to permit accurate cam installation. All
0.050-inch timing specs entered into the
Dyno2000 are internally converted to
seat-to-seat timing. Because there is no
way to precisely perform this conversion,
always try to obtain and use seatto-
seat event timing.


So they want me to measure the seat-seat measurements of a cam i don't have with a dial indicator.

ME Leigh

The recommended lash is .016" and the IIRC comp measure there seat-seat duration at .006"

AJ_92RS

Yup.

That's the way to do it.

I don't know about the .006" thing from Comp though. I thought that was just the way they measured advertised duration for both hyd. and solid (lifter lift that is). :shrug:

HiTech5

iTrader: (4)

A solid cam is a great cam upgrade. Just keep in mind that a solid flat tappet will require valve lash adjustments and a good set of valvesprings.

When I changed from a hydraulic roller to a solid roller, I immediately noticed a difference in the way the motor revved above 5000 rpm. The motor almost felt like it was on nitrous!

www.geocities.com/dzperf

Streetiron85

I'm confused, or at least I think I might be.
So bear with me if the info I'm giving is erroneous or not applicable.
But with the Comp S/R cam, the intake duration is:
274 Advertised
273 @ .015
236 @ .050
The lash is .016

That's off the spec card from the used cam I got from you, Leigh.

So I guess that would mean that the advertised duration is only an approximation. Right?
Or at least with the solid lifter cams, it looks like the adv duration has nothing to do with the .006 duration.

BTW, I like the second graph you posted better than the first.

Damon

Solid lifter cams primarily derive their benefit from being able to use more aggressive acceleration rates both opening and closing than a similar hydraulic lifter can tolerate. More "area under the curve" over the whole lift profile. They are also more "stable" in the upper RPM range since there's nothing to "pump up" inside the lifter if the springs start to lose control of the valvetrain.

Even if you could easily compare specs apples-to-apples between the two styles of cams (which, as you have seen, is not so easily done) it still wouldn't tell the whole story.

My expereince, in general, is that a solid lifter cam will give a nice bump in power as long as you're talking about a reasonably stout engine. Something that's going to see some RPMs and put out some decent HP/ci. If you're talking about a mild daily driver you'll probably gladly trade away the modest power gains for a quieter valvetrain.

I probably wouldn't bother with a solid lifter cam unless I was getting up into the 230* @ .050 kinda duration range and planning to rev over 6000 RPMs.

It sounds like I'm not a fan of solid lifter cams, but actually I am. They are great bang/buck if you're trying to build a low-buck motor that can still put the smack down.

ME Leigh

Well this isn't really a daily driver, i live in a small college town and barely ever drive more then 15miles. I'm going to use this car for mainly racing, Auto-x mostly. I have a 78 F150 6-300 that i drive around mostly.

As for added noice, i have the rear interior stripped and no rear seats, so noise smoise. I don't care about some stinking noise.

I'm just looking for the most power i can get out of my 305 without doing alot of work and spending alot of money. I want to port the 416 heads and swap the cam this winter. I'm not looking for much just the best overall power i can get.

I think i might try it just for the hell of it, what do you think?

AJ_92RS

That's always a good reason in my book.