[Cliff R]

"No offense intended here Cliff,but you gotta stop constantly bagging on flat solids just because ya'll picked too small a solid cam to get the results you were after,that was'nt the fault of the cam,or the lobes chosen,that was ya'lls fault for not fully understanding their practical application."

No offense taken, just stating facts.....and...I'm sorry, but the paragraph above is absolute, utter NONESENSE. Go to any Pontiac website, and post a general question about camshaft comparisions. 455 , 10 to 1 static cr, 268cfm heads. What do you think will make more power, 231/240/113 with .520" lift, or Comps XTQ (there very best flat lobes) flat solid grind with 240/248/112, .580" lift?

We have heard for decades two things, with solid cams "what you see is what you get"....and..."pick them about 10 degrees larger than a flat hydraulic cam to account for the lash".

Until we did the real world testing, or back to back dyno comparison, no one ever told me I needed neary 20 degrees @ .050" to make up the difference!.......Cliff

[screamingchief]

No offense taken, just stating facts

No your just stating one set of facts,based on one single experience.

That does'nt determine the only truth on the subject.

Just the truth for that one cam,in that one situation.

That's not the truth for all solids in all situations.

No offense taken, just stating facts.....and...I'm sorry, but the paragraph above is absolute, utter NONESENSE. Go to any Pontiac website, and post a general question about camshaft comparisions. 455 , 10 to 1 static cr, 268cfm heads. What do you think will make more power, 231/240/113 with .520" lift, or Comps XTQ (there very best flat lobes) flat solid grind with 240/248/112, .580" lift?

Just because lots of other folks out there dont have a clue about what they need when putting a solid cam in a pontiac,does'nt mean all of us folks have that same problem.

BTW,who decided the XTQ lobes are comps best?

If they're "all that" why bother to have any other lobes...

Did they throw the other lobes away after they offered the XTQ lobes???

We have heard for decades two things, with solid cams "what you see is what you get"....and..."pick them about 10 degrees larger than a flat hydraulic cam to account for the lash".

Until we did the real world testing, or back to back dyno comparison, no one ever told me I needed neary 20 degrees @ .050" to make up the difference!.......Cliff

Who said that was the criteria,does'nt matter anyway,they were wrong.

That should be obvious in hindsight.

That's some BRANDXXX nonsense,I've known better for years now.

Yeah,utter nonsense indeed.

[68birdfreak]

OK...ENGINE BUILDER SAYS GOOD TO GO WITH HYDRAULIC ROLLER...LETS GET IT ON!

[screamingchief]

Good luck trying to get straight answers on HR specs from some folks here...

If they dont give you lobe #'s,or a peak at the cam card itself,they're likely wasting your time.

Anybody can share their "basic" cam specs for advertised duration/.050" duration/lift/LSA whatever,but understand that the actual lobes used can make major differences in the end result.

Some of us here are pretty good at reading between the lines and figuring out the data that is'nt being shared,but other folks just are'nt that familiar with the subject to solve those riddles.

Lots of the time the actual lobes/no.s being used or valve timing info fails to be mentioned by those who are supposedly "sharing" data with the rest of the good folks here...

Hmmm,,,I wonder why???

Expect some weak reasons why they cant tell you that info.

Uhhh I dont have the cam card in front of me right now,,,uhhh I lost the cam card,,,uhhh it's a proprietary cam grind,,,yadda,yadda,yadda...



Man,,,I'm just grouchy as hell today,,,must be the friggin 18 straight days of rain here...


Cam choice for a HR isnt all that different from the selection of a flat tappet hydraulic,but understanding the unique differences between each style of cam is the more complex subject,your best bet is to browse the custom lobe sections of your prefered cam companies and find yourself some lobes that fit your needs,then if you have questions talk to your builder and the cam company your dealing with,I would'nt rely too heavilly on "generic" advice from any source unless the source giving said advice is willing to get real specific about their cam specs.

Shelf HR grinds are fine if your not too worried about squeezing every drop out of the combo,and if that's the case,then you dont really need that sort of specific information,as shelf grinds are what they are,they're pretty much all the same as the next cam on the shelf.

JMO.

Good luck with the project.

[Ron H]

Alot of money for a hydraulic roller. Could be some money better spent elsewhere depending on you car. But it's your car, your cash. Good luck.

[Cliff R]

SC, we have a LOT more than one single experience from cam testing. Remember, we have a dyno 11 miles from my house, and it sees SCORES of Pontiac engines, prepared by hobbyists with nearly every engine and cam combination every thought of. If I published what I knew about a couple of the cams mentioned in this thread as NOT working very well, or coming up WAY short in power production, it would only serve to start a heated debate.

Don't take my comments the wrong way. I got my rear spanked pretty good when replacing my "old" school RAIV cam. It was my nickle and my time, and my rear that got singed pretty hard. I've never seen another test anywhere, where someone changed ONLY the cam and posted the dyno results.

Here are the facts surrounding that experience.

The engine had 5 years and over 1000 documented runs on it.

It was out for "freshening up". It had been slowing down, I just figured the cam was wearing down or the rings loosing their seal, turns out the timing chain was about to walk off the gear!

I wanted to replace the cam with a solid grind as I don't mind running valves once in a while.

I wanted to take advantage of the "new" technology.

The MAIN goal was to make more power in the same RPM range, 3000-5500rpm's.

The cam was chosen based on .020", .050, .200 @ .050" numbers, and gross lift with 1.73 rockers.

KRE helped with the cam choice. Comp Cams concurred, but recomended we put it on a 110LSA.

The only real difference in the two cams were the type of lobes used, at least that's what it looked like on paper.

My engine power dropped from 494hp/549tq, peak hp at 5600rpms, to 482hp/537tq, DONE at 5200rpm's.

Where I messed up was not factoring in the .006" duration, or how long the valves were actually off the seats.

My engine cared more about total valve movement in degrees of crankshaft rotation, than it did about having more movement (greater area under the curve) provided by the new cam.

In basic terms, the "new" technology did not make up the ground lost by the quick opening and closing specs, lost actual overlap, etc.

Try thinking about these things from a "dynamic" standpoint, and not a "static" view. The time in milliseconds we give the valves to be off the seats, has a dramatic impact on the amount of air that we can move thru the engine.

My opinion, the slight amount of improvement that we get with the quick ramp, or modern flat lobes, is NOT nearly as great as we are led to believe.

Typically, folks do NOT look at cam choice in actual time the valves are off the seats. when the valves are opening and closing 40 times a second, or more, time becomes a factor in airflow thru the engine. Opening and closing valves are like "slamming" doors shut, and causes effects thru the intake and exhaust tracts NOT seen on flow benches.

Until we did a flat hydraulic to solid test, we had NEVER heard exactly how much one should increase the .050" specs to make up the difference from having lash? It didn't matter with the cam we chose, I ran the lash clear down to NOTHING trying to get more power from the cam, prior to replacing it, the power numbers didn't budge!

In closing, Selecting the right cam, as we found out, can be a "bundle of snakes".

Roller lobes can do what flat lobes can't even think about doing. We saw immediate power improvements with the Hydraulic Roller cam. Not a lot to start with, but with some quick "tweaking" we found quite a bit of power.

There are additional benefits not always mentioned with the roller lobes. The engine revs quicker, and oil and water temperatures in the engine are degreased significantly. I'm glad to hear that the decision was made to go to an HR cam. At least they woln't be scrubbing a lobe and can take advantage of the roller technology......Cliff

[screamingchief]

I know what your saying Cliff,and I know which grinds your refering to as being suspect in this thread,I just feel at times you get in a hurry posting and dismiss solids as SOP these days because of that experience when I know from personal experience that there are plenty of pontiacs out there with flat/solids that all run extremely strong for what they are,and these are'nt high $$$$ affairs either,some are serious "low budget" machines that really should'nt run as well as they do.

I dont have any issues with you strongly cautioning folks to choose carefully if they elect to use a solid,I wont argue that,as you guys found it can indeed be a bundle of snakes,I just dont see why you often seem to convey the impression they dont have any viabillity with regards to some builds,it not like they're inherently flawed in design or such...

Complex,sure,more-so than many others may grasp,absolutely,but you guys seemed to have learned a bunch with that venture,what you said above is totally logical,and valid,knowing that now would not your next attempt at a flat/solid surely fair better and get results more in line with what you would be after?

I know some of us others have figured out how to choose which solid/flat cams will likely get a specific result in our pontiacs,so from that we also have a pretty good idea what is often needed to get a desired result in other situations too.

I just feel that the flat/solid remains an extremely viable option for many combos,especially with regards to a $$$$ per HP basis.

There comes a point with hydraulic cams where I feel there are diminishing returns,and there is often a point where their design traits start to become a drawback when compared to the solid cams.

Granted for most "street" builds (and some street/strip builds as well) this really isnt always that big an issue,but I feel once a fella is inclined to start going after more power and quicker ET's they're gonna hafta take the plunge sooner or later.

I admitted I was a bit punchy yesterday,when I first got on here there was a mix-up on another thread I posted some nice pics on and it got me kinda bent outta shape,so that angst kinda got carried around with me as I posted on some threads,and this one kinda got under my skin.

I did'nt really mean to dog on you here.

Oh well,gotta go it's way late...

[Cliff R]

SC, no offense taken in any way. My goal is to post accurate and useable information, as we know it to be from direct experiences with testing parts, and different combinations of parts.

The solid cam test was a big disappointment for us. My goal at the time was simply to make at least as much power as the old cam, in the same rpm range. When it came up WAY short, I had to start looking closely at the actual valve opening and closing events. Seems there is more to choosing cams than just .050" numbers for actual comparisons. This quick ramp technology reduces actual overlap, and provides shorter seat timing. This may account for having to choose them quite a bit larger than we predicted, in addition to allowing for taking up the lash for the solid grind?

Instead of going down the same path again, with a 250/260 solid cam, we went to a smaller HR cam, and absolutely LOVE the results. Great idle quality, broad power curve, strong power from the instant the engine is loaded to the shift point. It revs quick, and runs cool enough to hot lap it in near 100 degree temperatures......Cliff

[Steve C.]

Cliff stated, "My goal at the time was simply to make at least as much power as the old cam, in the same rpm range."

Power in the same rpm range.... that's a subject we might consider when we talk about changing from a hyd flat tappet to a solid flat tappet cam. In the past it was quite common to see it stated to add 8 to 10 additional degrees of duration with a change to a solid cam. And today many are finding it could be 15 or more additional degrees duration.

So what happens to the operating range with the added duration. I have seen it stated the old rule of thumb is a change in 10 degrees plus or minus will effect power curve plus or minus 400 rpm.

Now add 15 additional degrees of duration .... might the combination now need more converter stall and/or more gear ? ? Something to consider.

[Cliff R]

Steve, just by estimating the dyno numbers, we would have needed about 20 degrees MORE duration with the solid to just be close to the old cam. But there are several things to consider, not just the fact we went to a solid grind. The lobe profiles, quick opening/closing ramps and actual .002" tappet movements were radically different with the "modern" lobes compared to what I was using previously.

This only throws another monkey wrench into the mix. In any case we came up WAY short on power production. Anyone looking logically at what we had done would immediately assume we would have at a minimum, made close numbers, or even a tad more power with the new cam.

Just before removing it, we ran the lash tight, and saw ZERO improvment in the dyno numbers. My engine just didn't much care about the "trick" lobes, it wanted the valves open longer in degrees of crankshaft rotation, and the additional 11 degrees of actual overlap provided by the old cam.

Another thing that really surprised me is that peak torque production fell off so much. One would also think that the "modern" lobe profiles would have INCREASED cylinder pressure in a slightly narrower rpm range, especially since they have greater "area under the curve", combined with less actual overlap.

I'm no cam expert, but the lesson learned with our testing was costly, in terms of time, money and POWER. Guess I'll stick with the roller stuff for a while, at least we don't have to worry about "scrubbing" a lobe with all the soft materials in use combined with recent changes in the quality of lube oil(s).....Cliff

[Ron H]

Cliff, I would like to see a swap to an Ultradyne 280/288 solid from were you are now. It might be slightly behind the HR cam you have now but it would make more power than the old HYD cam you had in there. I bet the main reason for the slight loss over the HR cam would be less lift.
247/255@ .050 with a 1.65 rocker .577/.594 before lash LSA 110* 106* ICL.
Maybe someone can input your combo into a dynosim and then swap the cam and see the differences?

[screamingchief]

So what happens to the operating range with the added duration. I have seen it stated the old rule of thumb is a change in 10 degrees plus or minus will effect power curve plus or minus 400 rpm.

Now add 15 additional degrees of duration .... might the combination now need more converter stall and/or more gear ? ? Something to consider.

IMO Steve with flat tappet solid cams in pontiacs a lot of rules get thrown to the wayside,what works for other makes really does'nt translate very well to our ponchos.

The RPM ranges dont seem to get shifted around as much with these solid cams in pontiacs like they may with other makes,especially if the LSA is'nt moved around a bunch,this seems even more true when we install them to keep the ICL pretty close to each other.

Lets take a moment and look at the commonly asked question "how to choose a solid to compare with the 041 hydraulic",I will link to what I had to say on the subject in another recent thread:
This thread covers what I recommend for the minimum solid to compare against a true 041 hydraulic:

RAIV/solid thread.

And do note I also stated that the #60311 cam would need to be used w/1.65 rockers.

And for an optimized 041 hydraulic "clone" I might have even suggested a bit bigger solid,depending on the lobes in question.

That "pick them about 10 degrees larger than a flat hydraulic cam to account for the lash" stuff is a way old school BRAND XXX based axiom IMO...

And most all the "respected" pontiac people (with actual solid cam experience in pontiacs) that I've talked to about pontiac solid cams thru the years said it was a load of BS as well.

Dan Whitmore agreed when I spec'd out a solid cam from him yeeeaaarrrsss ago,it's not like a few others had not come to understand the hydraulic lobe/solid lobe/pontiac conundrum.

That has been pretty much the same information I've understood for many years now,take for instance a solid cam I ordered a good many years ago from Dan Whitmore,this cam was chosen as an ever so slightly "larger" RAIV style solid cam ground on a "tight" LSA,this cam was even bigger than the #60311,but it also used the modern "fast" lobes,I'll include the specs of that cam for the sake of debate.

It was chosen as a refined 290b6 style grind from crower,the main differences were the reduced intake/exhaust duration split,and the 108 LSA.

That custom solid (Crower #E27941) I ordered thru Dan was ordered back in late '98 early '99,so this information is not even close to being new...

The hydraulic I had at that time to use was the crower #60210 hydraulic that I mentioned above,and that cam is now going into the '72 bird.

All those parts were bought around the same time for 2 very similar 455 builds.

I had two venturas then,a '73 hatchback "street" car,and the more serious '74 "street/strip" car,the '74 was to get the solid cam & good bottom end for a few more RPM and also for mild nitrous use,the '73 was to use a hydraulic and unported 6X8's with more "mundane" hardware.

My only real reason for deciding to opt for a solid cam on that one 455 build was to up the useable RPM range a bit compared to a hydraulic as the rods & pistons for that project 455 would have been forged,not to drastically change the power curves intended for that project.

I feel the #60210 and the #E27941 are almost close enough to be comparable,and they have a 27 degree difference @ .050" on the intake side!!!

But do note the seat timing as well,,,the plot thickens right...

And if I were getting a solid on a relatively "wide" LSA,that would also need to be taken into the final choice as well.

The flat tappet solids seem to me to be very "forgiving" if you "go big" when compared to any hydraulic,ask me it would be hard to over-cam a flat/solid pontiac that is remotely well built.

And the car this 455 with the custom crower solid (#27941) cam was to go in would have been virtually a twin to your ventura Cliff,and do note this was looooonnnnggggg before I had ever heard about you or your car as well,my car at the time was a '74 ventura,th400,3000 stall,3.42 rear,26.5" tires.

The engine would have been with a port matched torker II with an 850 double pumper,whitmore ported #96's (250ish @ .050"),TRW/eagles .030" over,the aforementioned solid,1.65 rockers,and the rest was pretty basic stuff.

I expected the solid cam equipped '74 to be a tiny bit "lumpier" and such,,,sure,,,and it would have used a bit more stall (3000-3200) for the convertor than the hydraulic #60210 equipped '73 would have gotten (had a 2400-2600 unit for that one),but really the parts between those two cars could have easily been swapped between each other without hurting either combo to much IMO.

The goal was 550 or so HP on pump gas,mid 11 second ET's or better,and I feel it should have easily gotten there.

I've included cam cards for my current crop of cams,debate away.

I've also included the crower #60311 for the sake of discussion here.

Oh BTW,if ya'll want to see the .050" valve events for the comp 290b6,lemme know,I got those figured out around here somewhere,for some reason comp does'nt list their timing events @ .050",also I believe I have the seat valve timing events for the other crower cams as well,but I gotta dig around for those.

Here's a hint,,,look at the intake closing and exhaust opening events on the #60311 and the #E27941...

The IO and EC are'nt a whole lot different either.

Food for thoughts fellas,this should get real good.

HTH

[Ron H]

SC, those 2 solids are close to the 288/296 solid Ultradyne I am running now. Though my KRE heads are the 310 ported by them version, my times speak for themselves at the power potential of solid cams in those ranges.
Intake Opens 25.5 BTDC closes 49.5 ATDC 255@ .050 .360 lift @ lobe
Exhaust opens 65.5 BBD closes 17.5 ATDC 263@ .050 .3706 lift @ lobe
108* LSA 102* ICL
I run a 1.65 roller rocker.
Corrected I should be about 610 FWHP.
Actual HP on the track around 505 HP @ 7400'DA. 10.69 @ 125.75 mph 2870 lbs.
Mike Davis ran 10.80's in Texas I think with 310 E Heads and 3800 lbs.

[screamingchief]

SC, those 2 solids are close to the 288/296 solid Ultradyne I am running now.

Indeed,that's why they're extremely popular,they work!

I feel they're the solid equivalent of the aforementioned crower #60919,that is they are proven performers!

Mike Davis ran 10.80's in Texas I think with 310 E Heads and 3800 lbs.

Met Mike a few times years ago,Steve C. knows him pretty well too from what I understand.

Here are the remaining valve events I mentioned the cam cards dont contain:

Crower #E27941 custom seat to seat events:
IO @ 40
IC @ 68
EO @ 78
EC @ 34

Crower #60311 seat to seat events:
IO @ 38
IC @ 74
EO @ 79
EC @ 43

Comp 290b6 .050" events:
IO @ 21.5
IC @ 53.5
EO @ 59
EC @ 27

Crower #60210 hydraulic seat to seat events:
IO @ 35
IC @ 63
EO @ 76
EC @ 32

Things that make us go hmmmm...

Sorry about that last bit.

[Steve C.]

SC- You might be thinking of Bob Davis here in Austin with the white '64 Tempest.

Good example was the change Lee Atkinson made from a 231/239 hyd flat tappet cam to a solid flat tappet with 247/247 @ .050, gained about 2 tenths and about 4 mph, yet indicated the driveabilty was not greatly effected. With 296 rated duration on the hyd cam verses a 280 rated duration on the solid the overlap makes a differance.

( As demonstrated in that other post I found some odd results using input based on seat timing. It makes a big differance on input with advertised duration or duration at .050 tappet lift . Can be so confusing )

[screamingchief]

SC- You might be thinking of Bob Davis here in Austin with the white '64 Tempest.

Doh!!!

Yeah,,,Bob is the guy,,,pilot for an airline or something of the sort IIRC.

Mike,,,Bob,,,I'm the worst at remembering names I dont use all the time...

Sure confuses the dogs when I get their names wrong,they just give me this blank stare like I'm a lunatic or something!

Not sure if that's who Ron H was refering to though???

[Ron H]

Mike Davis is who I am reffering to. He had his Goat in HPP last year around this time. He is a member here.

[screamingchief]

Familiar name,think he ran in NSS at one time.

Yep,checked the profile,now I know who your talking about!

Been awhile since he posted IIRC.

(His profile says:Last Activity: 03-31-2007 12:15 PM)

The HPP article says he hails from Georgia though,did he move to Texas,and if so where-abouts?

Yeah,those two names are close enough,now I see why I mixed them up.

Mikes GTO is indeed a strong runner,as I said,flat/solids are definitely a viable choice IMHO.

[MrPushrod]

Originally Posted by Indian Uprising

what do u shift/stage at?

also are u running trick springs up front? If so what rate? I looking to get a set but am having a hard time finding a place to weigh my car.

I shift at 5200 on the nitrous.
Stock springs up front.

[performerrpm]

how well d you think that xe294 would do in my 455 mr pushrod it is a 455 030 over 72 e heads 11.5 cr 4 speed 4.11 i want one that has a pretty radical idle but nt so much that the car sounds good but dont run. i have the xe274 ow