I'm trying to understand more about solid cam specs. I'm having a hard time finding any "useful" guides on choosing cam specs.

Whats making me confused is that profiles are much more aggressive thus I have a hard time relating duration @ .050 with respect to hydraulic cams.

Say you wanted a shift point around 6800 or so RPM with a very choppy idle, what specs would one go with? Jason99TA ran a cam with 230/230 or so. I've heard of LS1s with cams upwards and over 250/250.

HELP ME UNDERSTAND THIS STUFF please <img src="graemlins/gr_hail.gif" border="0" alt="[hail]" />

 

nobody out there knows anything about solid rollers??? <img src="graemlins/gr_cry.gif" border="0" alt="[whiner]" />

 

It really depends on the lobes and the setup of the rest of the cam, valvetrain, etc.

A common approximation is to subtract 6-8 degrees at the durations that are common here to find the hydraulic "equivalent" - of course it wont really be "equivalent" or else there would be no reason to go solid - but it should give you an approximation.


Chris

 

[quote]Say you wanted a shift point around 6800 or so RPM with a very choppy idle, what specs would one go with?<hr></blockquote>

Brian, shifting at only 6800 rpm kind of defeats the purpose of even going with a solid roller. Hydraulic cams can handle that rpm no problem. If I were to go solid roller, I'd want to shift no earlier than 7500 rpm to take full advantage of why you would go with one in the first place, go get more rpm! <img src="gr_grin.gif" border="0">

HP = (Torque x RPM)/5250

The simple relation describes everything <img src="graemlins/fluffy.gif" border="0" alt="[Fluffy]" />

Tony

 

NineBall,

I know you are a smart man, and understand that there will be incremental tq increase across the powerband.

Those square like lobes allow for better cyllinder filling, because you get to peak head flow quicker in terms of cyllinder time.

I have seen some crazy 410rwtq numbers out of LS1 on hydraulic cams though with 11:1 CR.

I wonder what is possible with a squarelike Roller cam with a similar powerband and same parts.

 

its looking like we may find out soon <img src="gr_stretch.gif" border="0">

 

http://www.thunderracing.com/index.c...t&contentid=35

There goes a setup with solid cam and T1 like powerband.

442rwhp/416rwtq.

Looks like the dyno necks down hard at the 430rwhp mark, indicating that perhaps the LS6 intake simply chokes off around this point.

I wonder how these large strokers look with LS6 intake, they probably hump over at a point and any addtl power is hard to come by as a result of the LS6 intake.

 

Dennis, look at these nice examples of a hydraulic cam with the same powerband:



The red graph is a local guy's car and has the 222/222 112 "Hammer" cam. His car is also turning 17x11 SS wheels with 315 tires on the dyno, known "dyno" power killers.

Is the valvetrain cost really worth it? Look how well a tiny hydraulic cam can perform in a good combo.

Now, Judson's 375ci solid roller that put him into the mid-10s was pretty slick, it pulled about 500 rwhp corrected. Badass!

Tony

 

thanks for all the info Geoff <img src="gr_stretch.gif" border="0">

I now have a better understanding

 

[quote]Originally posted by Nine Ball:
<strong>

Brian, shifting at only 6800 rpm kind of defeats the purpose of even going with a solid roller. Hydraulic cams can handle that rpm no problem. If I were to go solid roller, I'd want to shift no earlier than 7500 rpm to take full advantage of why you would go with one in the first place, go get more rpm! <img src="gr_grin.gif" border="0">

</strong><hr></blockquote>

6600 shiftpoints and almost 126 mph on slicks... I think there is a benefit to going to a solid setup like mine, especially if you plan to run the stock bottom end. <img src="gr_grin.gif" border="0"> Anything over 7000 rpms will kill a stock shortblock in no time. Sure, there is an added expense to going the solid roller route. However, your valvetrain will be rock solid and for any other future motor buildups (all-bore, 422ci motor,etc.), you will already be setup for a nice solid roller in there as well.

If I were to build another shortblock with forged pistons and a nice set of rods, I would look into going with a slightly bigger cam than what I was running (230/230 .612/.612 112lsa) and more compression (closer to 11.8:1; I was running 11.2:1 previously). Still, I wouldn't turn the motor much over 7k, given the stock LS6 intake manifold. Until we get a bad *** intake, I wouldn't think about spinning my motor much past 7k rpms. If you do plan to do this (past 7k w/ LS6 intake), you are going to have to go HUGE on the cam specs and run a crap load of compression. I don't think this would be too much fun in a daily driver, something which my car is.

Brian, if you have any questions on how my car drove, sounded, etc. with the solid roller compared to the B1, shoot me an email or call me at the shop tomorrow. I would be glad to answer any questions you have.

Jason

[ January 08, 2002: Message edited by: Jason99T/A ]</p>

 

one thing i'm surprised many of you haven't said is the LIFT capabilities...how many .650+ lift hydraulic cams do you hear people running without many problems?

now how many of the above with soild?

see my point?

when cams become a little more extreme, if you go solid, they will idle better and perform better.

Someone said RPM capability...this is sorta not true. I do agree you want to shift with a solid roller around 7000rpm at the minimum. Reason being with the solid lifter and big lift capability...at the higher RPMs you will be generating more hp if you're heads can flow it.

But it is all about combination people...look at Tom Guellich. He has an all motor 427ci in a 86Z that goes 9.80s and only shifts at 7100rpm.

With solid roller cams the lifter doesn't have to worry about keeping itself on the cam since it is solid. This means that the opening/closing ramps on the cam itself can be made FASTER to open/close the valves quicker/snapier to create more hp but there is more valvetrain noise, maintenance and wear.

 

[quote]Originally posted by Jason99T/A:
[QB]

If I were to build another shortblock with forged pistons and a nice set of rods, I would look into going with a slightly bigger cam than what I was running (230/230 .612/.612 112lsa) and more compression (closer to 11.8:1; I was running 11.2:1 previously
QB]<hr></blockquote>

Thats interesting Jason, this is kinda what I was discussing with Geoff today <img src="gr_images/icons/wink.gif" border="0">

236/236 .6xx/.6xx 112 with 11.5:1 Interesting <img src="gr_stretch.gif" border="0">

 

Awesome Brian! Check your mail... <img src="gr_grin.gif" border="0">

 

Look at where the 400rwhp was made - only 5000 rpm.

Seems like he has about 200rwhp @ 3000 rpm, 300 rwhp @ 4000 rpm, 400 @ 5000 rpm, but only eeks out another 45rwhp from 5000 to 6500.

The dyno graph looks to be that of one that has an intake setup for the wrong resonance tuning range. It necks over hard.

I'm looking at these dyno's of the 422 strokers, and they neck down hard too, with the last HP being hard to come by.

 

HP-GURU is right that with a smaller solid you'd have more power everywhere but Tony's sort of right also because you'd be spending a lot of money when you could do a bigger solid roller and have a LOT more power up near the top. You can have only so much VE and then you have to turn more RPM.

 

Give me a call at the shop!!! (225) 754-7223.

 

I also think that the implentation of solid rollers in these cars are in their infancy stages (especially at the 346 cid level) But once the valvetrain is setup, a different cam is just a swap away <img src="gr_images/icons/wink.gif" border="0">

I think trying something a "tad" more aggresive than jason's old setup might work well IMO