572 cam recommendation

Who has a good cam recommendation for a 572 with indy 345 cnc 2.25 intake 181 exhaust heads. Indy tunnel ram with to alky 750 carbs. 14.1 compression with diamond flat tops. 4.500 bore 4.500 stroke. I have a set of 1.5 t&d or 1.6 T&D rockers i can use.

Race only setup in a dragster weighing 1955lbs with a 4.30 gear and 33.5 x16x16 tire.

Thanks in advance

Call Fast68Plymouth, Dwayne Porter. 802-951-1955

I don't have a recommendation, but that monster is going to need one big honkin' cam! sounds like an awesome, big power combination. GOod luck with it.

Select the cam and then get the converter built to work with that cam

I have 6 convertors from a supplier that i am lucky enough to get to gunnie pig. So convertor selection is not a problem. We pretty well know what each convertor does in many different usages already and can pretty much pick out which one to use to start with.

Do you know what engine RPM you want to shift at and what the RPM is at the stripe?

What size cam tunnel,and how often do you want to change springs? How much valve pocket do you have in the pistons, or can they be cut deeper?

Very good advise. Ron

This what I run. 15-1 572, ported -1. Comp; RX 1718 int lobe (285@.471"). XCX 1862 exh lobe (292@.471") ground on 112 LCA (gross lift .799"). Uses PAC 1224 spring @1.950. T&D paired rockers 1.7 ratio. We checked the last set of springs at 200 passes. No pressure loss, same as the new set. With 440-25 Indy cross ram and 2 Eddy 750's the car will run 9.1-9.2 145-146 in any weather at 3340lbs. Best of 9.00@150. Lash stays consistent.
Doug

Right now i shift at 7000 and cross about 6800. Somewhere close to that is kinda where i want to stay.

Thats with the convertor flashing at 6120 via the racepack.

The valve pockets are plenty deep.

The block is the older mopar mega block.

I make 350 passes or so a year so i do like something easy on the valve train.

I am still running the same the cam i had ground for my 528 years ago and then i switched to the 572 combos in 2011.

Just thought i would put the correct cam in it to make it a little more stout.

Want to be in the 4.70s in any weather instead of the 80s like it is now.

I'm guessing your cam tunnel is stock, so here's a stab. I'm thinking with that many inches, and those heads, your motor will peak around 6800-7000. I'd try this if you want to get after it. 288/302 on a 114. Keep the lobe to .5 since the core is small.

What are your current cam specs? If you want to cross the line with the same RPM as your current cam then you probably don't want to change the duration a bunch.

With 1.5 rockers it is

Intake lift 700 ... Lobe 4668
Exhaust lift 715 ... Lobe 4765

@50 Intake 286 and 109 ATDC
@50 Exhaust 306 and 115 BTDC

Advertised Duration 326 intake and 356 exhaust

With a STD cam core keep the lift reasonable. You didn't mention a rocker ratio but assume 1.5/1.6. We run a 572 in our Racetech, its been 4.60 here in Las Vegas. Id look similar to what's been posted FWIW here is what we had in ours 115 center, 283/299, .474/.475 with a 1.7 rocker gross lift at 806/808.

AL i have my older set of 1.5s and a brand new set of 1.6s .. Not sure which to use to be honest.

Those lobes were probably designed for someone, or a particular combination........ they’re not in the lobe catalog.

Yes that is the cam that was made for me years ago for the 528CID

Do you have flow numbers for the heads? I would think that those heads would flow pretty well up past 0.800 so if you have the budget to put more lift in the engine you might find some power there.

Seems to me your existing duration is roughly correct but you could probably pick up some power with more lift. However, adding more lift and keeping the same duration means that you are going to be using a more aggressive lobe which means everything gets beat on harder.

In my 514 race engine I use a Crane R282/481. That cam is 282/288 at 050 and has 0.481 lobes. With 1.70 rocker the gross lift is 0.817. That cam might be a touch small for what you are doing but I'm thinking it would make more power than what you have now without changing the peak rpm much. My 514 makes about 900 hp on the dyno with Indy EZ heads and a single Dominator. My compression is 15:1 so close to what you run but I'm 60 inches smaller and don't have the tunnel ram.

I assume you're running some sort of race header since it is a dragster? 2 1/4 pipes? 30 inches long? 4 inch collector?

We have never run our Racetech out the back door as my son is only allowed to go 7.50. We run it with 10 degrees of timing out of it and a small 1050 carb most all the time. The only time we ran it all out was in Salt Lake las year and he went 7.53 in 9200' DA. You don't NEED a ton of camshaft in a light dragster to get after it. We went 8.teens with a 446 in the same car here in Vegas with an OOTB -1 head and tiny roller on pump swill.

Headers are fab shop 2 1/8 to 2 1/4 with a 4 inch collector

No clue what the heads flow. Just bought them from indy and had them milled to 62cc and cnc'd . I know they need more work but i always like running them the first then over the winter work on them and see what difference is made.

Al you were running B-1 heads correct?

We have run B1, Indy -1 345CNC and OOTB -1 heads on the car. The cam in the 345 head and b1 heads were similar. The 345 head went 4.80's here in Vegas in GOOD air for here.

FWIW we run a MUCH smaller header as well. I know you know this but in a dragster with a glide the converter is gonna make or break the deal. We try to get to 6-700rpm drop on the shift. We have been 1.02 60' here in Vegas as well on a little bubba.

The entire car is apart now and we are redoing it from end to end. Also building a new engine, hoping we can go .50's here, not sure we will get there but that's the goal.

Well I'm sure you could pick up some power with a different cam but if you are using shaft rockers there is a limit to how big you can go before you'll have problems. Do you know what valve springs are in the heads and what the installed height is? If the heads came from Indy fully assembled then the parts might not be in the best shape. Indy sends stuff out the door assembled for shipping rather than assembled for racing.

Do you know what your valve to piston is with the existing cam? If you know that number and the installed height on the springs then you could get really close with the next cam choice.

Personally I don't think you need to change the cam much. Maybe put the 1.60 rockers on there and double check valve to piston and spring clearance. If the 1.60 rocker fit and work then try it at the track and see what it does. Since you already have the parts that will give you another clue.

K motion k950 springs installed at 1.950 i do believe.
The rule of thumb is .060 between coils correct to prevent coil bind.

I do have a ton of valve to piston clearance since the pockets in the pistons are a little deep.

K-950 springs bind at 1.150 so you can't run much more lift than what you have right now. You could probably run the 1.60 rockers but it is going to be close, especially on the exhaust. Maybe put a pair of the 1.60 rockers on and check them. With lash and rocker deflection you'll probably be okay but I don't think you can put a bigger lobe in there without changing springs.

I don't know what those lobes are that you have so I don't know if the K-950 will control the valve train at 7000 rpm with the 1.60 rockers. If you aren't having any problems now then maybe they can handle the extra beating that the 1.60 rockers will dish out but you'll want to keep an eye on it.

If it was me I'd put the 1.60 rockers on there and check it over carefully. If it looks like everything clears then I'd run it down the track a few times and see what data logger says. If it makes more power then that tells you the direction to go, if it doesn't then that tells you something too.

To step up to some faster lobes(I wouldn’t bother changing the cam otherwise), you’ll want to do something different with the spring pack.

My Valiant picked up pretty good going to 1.6 intakes and still using 1.5 on exhaust

I like the idea of using the 1.6 rockers, at least on the intakes. I think those carbs are way too small. This is what I'm using on my new 605 build.

WAY too big there buddy............

They may be too big for your little girlie street lowdeck. Perfect for a grown up engine.

Put shear plates under the carbs. Put a 1/2" spacer on the whole plenum, if it's the newer-style T/R you could make the spacer .75" thick. Use your 1.6 rockers on the intake side of current cam.

I'm assuming it is a single shaft system? I just went thru some old notes on a TD system with a 1.6 ratio (1.52 pivot). Measuring a .4765" lobe with .020 lash on a 760lb spring open load my NET lift was .735" FWIW
I'd guess your current NET is near .670" with the 1.5 rocker.

Good info.....

The 345cc Indy -1's can utilize much more than .700" lift. The exhaust side seems good. I like the duration where it is.

Ask around about those K motion springs. I had k1000h springs and broke a number of them in succsession . i am not sure about the 950s, but guess you might need more spring. I picked up a bunch just going to a comp 947, which had another 90 lb of seat pressure.

Just dug out the cam card and the spring requirements say closed 210lbs at 1.938 and open 650lbs at 1.278.

I checked last night at my k-motion springs are installed at 2.00 inches which is 245 on the seat and they are near 700 at 1.300.

Yes it is a single shaft system and with the 1.5s the cam lift checked 672 intake and 688 exhaust checking it cold of course with the lash.

I am going to stick the 1.6s on the intake side to try that out first.

Not gonna get to try it this weekend as my son and daughter in law are having a reveal party for our first grandbaby! And i darn sure ain't missing that over a dang ole race car!

In my case the k1000h were 225 on the seat, and the cam card called for that much, yet the car responded with almost a tenth gain in ET in the 1/8th! There is a whole lot more to picking the right spring than installed seat pressure, open presure, and coilbind. Spring frequency is VERY important, along with total mass. I am no expert for sure, but just want this information available to you so you can research it, and get the most out of your motor. Dwayne Porter is one of the guys to talk to. He has dynoed a lot of motors, and has a lot of experiance in this area

As I’m sure Greg can attest......... you can spend a lot of $$$ when you’re where you are to find a tenth or two.

My biggest gripe with the k-950’s is they don’t seem to hold up very well when the valve action starts getting quicker.
There are also plenty of people who have had surge problems and breakage issues using those springs, so I generally just use something else.

As for the cam, I don’t really like all that seat timing for the .050 duration and lobe lift.
I don’t think it would be too hard to improve on that cam......but just how much it would improve is the question mark.

All said, I ran your performance #'s and considering such a small cam and assuming you don't have trick ring packs and vacuum pumps and great valve jobs...YOUR MOTOR IS MAKING DECENT POWER now for the compromises. I'd guess you'll need about 50hp? or so for your stated goal? ...I don't see just a rocker change giving you that much but if you did both (well 3) things I suggested it should get you there assuming you don't have a plenum spacer and shear plates. Also as stated your maintenance interval will go up...lifter rebuilds? spring change intervals? with cam intensity. Maybe look at a PAC 1225 spring on the intakes.

Just adding to, so if you already know this, just ignore it, just trying to help.

The cam spec you have now will have radically different ramps as you add lift. Meaning a 286 with a .4 lobe isn't hard on stuff, 286 with a .56 lobe is brutal. The ramp has to get meaner to keep that duration at higher lift.

I think you need more spring as well, especially keeping those duration numbers with more lift.

If the OP is really making 350 passes a year, and is having good reliability at the same time....... I’m not sure I’d mess with it looking for a tenth.

I know for a fact he makes that many passes. He runs that dragster all the time.

He goes rounds everywhere

Man,,that is a lot of drag racing. Think about it like this. You go every saturday for a solid year, not missing a one. You make 7 passes on those days, and you've made 364 passes. Lots O racing.

We can race fri, sat, and sun. Around here all within 1.5 hours drive. He wins his share of bracket races

[quote=fast68plymouth]As I’m sure Greg can attest......... you can spend a lot of $$$ when you’re where you are to find a tenth

You bet! I could have bought a tunnelram, twin Dominators and a few barrels of q16 for what i spent trying to get the tenth i got! I ended up with an inverted flank cam from Mike Jones with .870 lift, 284 / 296/114 in my 528.

Thanks everyone for all the input.

I really like seeing everyone's thought on different topics. That kind of stuff may help someone else also that you don't even realize is paying any attention.

I do like to tinker and try to make my stuff as good as i can for the style of racing we do. Between the last 2 Saturdays i made 17 passes and the car varied .006 thou in 2 weeks. Luckily won 1 of them and then went 0006 red (after i smacked the bump down taking .005 out) at 10 cars the following week.

I am gonna try the 1.6 intake just to see and pass on if i see any noticable difference.

Will probably go ahead this winter and make the cam and spring change and straigten up the heads some.

The next 3 months of racing is pretty heavy for us after we get back from Vegas next weekend so as good as the car has been i'm not gonna do any major changes that i can't just change back at the track for the time being.

i really appreciate everyone's input and just because i don't reply back to each of them and i am paying attention to each and everyone and trying to store as much info as possible.

Thanks Again

If you have not investigate inverse flank roller time to do so
http://jonescams.com/drag-race/
shorter duration for given profile or
more area at the same duration
less side thrust so profile can be easier on the parts or more radical
your choice
Mike Jones is the only one I know of that can make these profiles rpm
uses small wheel for finish grinds
or
Get Rick jones to run his controlled induction software and generate cam profile which can be ground cnc by several different grinders
google "Controlled Induction"
look around the website and watch the demo
https://www.controlledinduction.com/home.html

Just a little update.. Hadn't got to do much experimenting on the car in the last month or so due to it has been very good and some weekends the driver has even showed up.

But took it to a small $1000 to win bracket race yesterday and changed my 1.5 intake rockers and put on the 1.6 intakes and left the 1.5 exhaust rockers on.

Car picked up .01 in 60 ft, .04 to the 330, and .06 in the 1/8th.

Mph only showed 1 to 1 1/2 mph gain.

So that gives me a little more info on what the cam want's at least on the intake side.

Have you tried tightening the lash? What Pushrod size? Do you have titanium valves? I am not sure of the value of Ti valves at your rpm, but would think it would take a lot of stress out of the combo as you get more radical on valve action and lift.

Did you monitor weather conditions on both days. Lots of new bests this time of year. The East coast guys live for Fall testing and new bests and climb out like hibernating bears.

I am building almost the same exact motor and should be going to the dyno within the next month. I have a cam that we are going to base line with and then custom grind a cam maybe the end of next season. This is my combo

572" Mitchell Alum block
Indy -1's 2.250 / 1.81 valves flowed 400/300 @ .800 & 409/305 @ .900
15.1 comp flat tops
single 4 on indy 3x intake
cam is .800 / .760 w/ 1.6 rockers (T&D) and 292/300 @ .050 on a 112 centerline

once I get closer to the dyno I'll post flow sheets and cam card and eventually a dyno sheet. I've had quite the long adventure with the block.

Haven't messed with lash on these 1.6 rockers. Only ran it yesterday with this combo of rockers.

Did run lash the same as the 1.5s.. But didn't want to get to tight cause it is close to the coil bind numbers.

I have 3/8ths 120 wall manton pushrods and stainless valves.

Yea weather was decent but not that great.. 2300 ft and 70 percent humidity .. Same weather in my crew chief pro which is pretty accurate said it was gonna go 4.896 first hit and went 4.837.

That would be some good information to have if you don't mind sharing when you dyno it.

I'll definetly share

Here is a recommendation i got back from Jones camshaft.

Cam# D440, R85510-89480-115
284/296 @.050"
.510"/.480" Lobe Lift
115 LSA

Any thoughts?

There’s really only one way to know how your car would respond to that cam.

I will say...... it doesn’t look like a “350 run” no parts replacement type cam.

But even that there’s only one way you’d really know.