Cam Specs.....where will the power be?

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thomasfouraker

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Called Comp yesterday and while the guy was very helpful and spent a great deal of time with me, he didn't see to be very confident with what he told me.

This is going into a 9.5:1 408 stroker Magnum platform
Airgap Intake, Ported 2.02 RT heads

Cam specs are:
224/230 .536/.544 on a 114 LSA installed
Intake open -2 closed 46
Exhaust open 49 closed 1

I am afraid this may move my power too high but perhaps the 408 will make this cam feel smaller than reports in 360s show.

Anecdotal dyno numbers show power is 2200-6000 on 360s. I would like more Idle-5000.

Hoping someone with some knowledge will help solidfy comps claims.

Thanks!
 
My uneducated guess is the lift is fine, the intake duration @.050. is low and the LSA too wide for the 408. If you got headers go with a single pattern cam. I’d say start somewhere close to 230+@.050” and 108-110 LSA Others could likely spec something more exact
 
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I get like 7.9 DCR. Should be ok with pump gas and probably knock your eyes out with bottom end torque.
 
What do you want
Street/hot street / strip and street
Need more info
Converter flash
Trans rear axle ratio
Tire and size
Etc......
 
Too many people see a wide LSA and flip out. That's great for a street car. It calms it down some, jacks the vacuum signal way up, and makes for really good street manners at the cost of very very little loss in peak power. So much so you'll never notice it. What it does do however, is add to the bottom end and mid range a good bit. It spreads the torque curve out wider and flatter. If you go to a 110 or 108 with the same duration @ .050, you'll probably be out of the range of pump gas, because that will give you an earlier IVC event and make cylinder pressure go up, raising DCR. You cannot stand "much" more than 7.9 with iron heads and pump gas. I think you're in a pretty good place with that cam. JMO.
 
Is that the XE274HR? Like previously posted, what is it going into along with the rest of the setup. If you have the stock Magnum cam core, Ken at Oregon Cam Grinders could set you up with one of these profiles, but the LSA of stock core is usually wider than what most people want. These two cams are the largest cams profiles he shared with me when I was asking about them for a friend. I’m sure he has something a step up that would be a better option for what you want. I think probably around 218-220 degrees intake with the stroker.

#1640

210/218 @ .050”, 270/280 adv, .531”/.558” lift

#1767

216/224 @ .050”, 266/274 adv, .546”/.557” lift
 
Brooks James said:
What do you want
Street/hot street / strip and street
Need more info
Converter flash
Trans rear axle ratio
Tire and size
Etc......
Click to expand...

Thanks for all the replies thus far!

This is going in a 2nd gen ram 4x4 ext cab about 6000lbs
Stock converter 1800-2000rpm
3.92 gears
33"" tires

Intent is a well mannered streetable truck I can tow with and have good usable power without having to reach far into the rpm range. Ideally shooting for power for typical driving scenarios. Not going to see a track. Will retain factory multiport injection and will be dynotuned.
 
Garrett Ellison said:
Is that the XE274HR? Like previously posted, what is it going into along with the rest of the setup. If you have the stock Magnum cam core, Ken at Oregon Cam Grinders could set you up with one of these profiles, but the LSA of stock core is usually wider than what most people want. These two cams are the largest cams profiles he shared with me when I was asking about them for a friend. I’m sure he has something a step up that would be a better option for what you want. I think probably around 218-220 degrees intake with the stroker.

#1640

210/218 @ .050”, 270/280 adv, .531”/.558” lift

#1767

216/224 @ .050”, 266/274 adv, .546”/.557” lift
Click to expand...

Talked to Ken last week and he isnt able to regrind my core. He suggest something in the 210/210 range staying around .515.
But he cant get small lift cores right now so told me to take the info and go hunting. The comp seems a bit more aggressive than what Ken suggested so it caused some second guessing of Comp suggestion as well.
 
Okay, thanks for the input! Hold up there on the big comp stick. While it's great for midrange power, but it's definitely the wrong cam for your overall combination's goals. There are some other shelf cams that I will hunt up will be that are much better suited for your intended usage. I will recommend a Melonized gear for your oil pump drive for your probably billet cam core, though. Hughes carries the gears or the complete assembled drive with gear, but my locally trusted machinist has also told me he can get the Melonized gears for $100-$125.
 
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You would have to use a fuel pump eccentric with the long snout in place of the Magnum bolt and washer setup, but the 1.6:1 magnum rockers would make .517 lift from the .323 lobe lift (.485 with 1.5:1 rockers). The 408 cubic inch displacement would drop about 300 rpm off the usable range, or close to 900 to 5200 rpm. This would make a wonderful towing package with plenty of extra "grunt and go".
Voodoo Hydraulic Roller Cam - Chrysler 273-360 (W/ Long Snout) 264/270
They appear to have it in stock, but I would call first.
Lunati Engine Camshaft 20200715; Voodoo 1200 to 5200 .485" .485" Retrofit Hydraulic Roller for Chrysler 273-360 "LA" Mopar
 
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Remember, roller profiles are vastly different than their flat tappet counterparts. Sometimes people tend to forget or disregard that. IMHO, I believe "whomever" you talked to at Comp knocked it out of the park. I think it's a great match for what you want to do and I wouldn't change it. ......and normally I wouldn't say that. That recommended grind does a couple of unique things for your combo. First, it jacks up the DCR "about" as far as you really wanna go on pump gas. Secondly, as I stated earlier, it will have excellent street manners and great vacuum signal because of of the 114 LSA. Don't forget the long, flat torque curve, too. Perfect for the street. I think it's a great choice and you'd be hard pressed to find a better one. Yall keep battin it around, but that's JMHO.
 
You're right on with that one with the hydraulic rollers being vastly different from their flat tappet counterparts. Light switch like opening when compared to even the most efficient flat tappet grinds. Comp shows a 110 LSA on their website, but it's that 38 degree ABDC closing that makes it such a forgiving piece. I didn't think about it until I looked at the cam card at the bottom of the page and the 110 LSA, but a question for Rusty.
Xtreme Energy 224/230 Hydraulic Roller Cam for Chrysler 273-360
Do you think an additional 4 degrees of advance would make it a little more goal friendly with off idle power?
The hydraulic flat tappet version of that cam installed at 107 does really well in a 391/318 stroker in 4200 plus pounds of 4X4, I would certainly think the hydraulic roller would be stronger. Alas, the 150 plus feet burnouts through second and third with the shift light on have finally caught up with the flat tappet comp cams, so a 1800-5500 rpm range Howards Rattler hydraulic roller cam with valvetrain upgrades is in the works.
Hydraulic Roller Rattler Camshaft; 1964 - 2003 Chrysler 273, 340, 360 1800 to 5500 Howards Cams 718005-09 | Howards Cams
I foresee finding the limits of the drive line and 9-1/4 axle after this.
 
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Garrett Ellison said:
You're right on with that one with the hydraulic rollers being vastly different from their flat tappet counterparts. Light switch like opening when compared to even the most efficient flat tappet grinds. Comp shows a 110 LSA on their website, but it's that 38 degree ABDC closing that makes it such a forgiving piece. I didn't think about it until I looked at the cam card at the bottom of the page and the 110 LSA, but a question for Rusty. Do you think an additional 4 degrees of advance would make it a little more goal friendly with off idle power?
Click to expand...

Oh is the thing ground on a 110? What are the new valve events for that? I'm way too lazy to figure it out....or more appropriately, I don't give "enough of a ****".

That said, if it's ground on a 110, then perhaps, there goes his pump gas motor. Because that's gonna affect the IVC event and not in a good way for pump gas. Now, if it was actually ground on a 114......which Comp WILL DO, then I'm all over it for this combo.

My bad. I slap missed that.......and I shouldda known better, because Comp slobbers all over 110 LSA like a cheap slut on a chocolate covered dick.
 
Why not get a 2nd opinion from another custom grinder ?
If the 2nd comes out about the same you can pretty sure its right .

Being for a truck vs car makes ahuge difference.
 
David Vizard tested 10,000 cam combinations for Crane cams. That testing, plus his decades of cam dyno testing showed patterns evolve. One was his '128 rule' [ look it up on the web ] & the other is a computerised cam program. The 128 rule is for determining LSA for parallel valve heads in general & works for CRs of between 9.5 -11:1. For splayed valve heads like the BBC, 131.5 is used instead of 128. Correction factors are used for higher CRs & blowers etc.
Until I can find someone who has tested more cams than DV [ no luck yet!] I have been & will continue to follow his advice.
In his Chev books, he says if you want a smoother idle/more low end, you do NOT widen the LSA, you reduce the duration. Yes, might be in a Chev book, but a Chev is just an air pump...like a Ford or Mopar.
 
I think I will give Brian at IMM a call and see what he suggest. Hughes suggested upgrading springs and going with an even larger cam that Comp suggested.
 
Bewy said:
David Vizard tested 10,000 cam combinations for Crane cams. That testing, plus his decades of cam dyno testing showed patterns evolve. One was his '128 rule' [ look it up on the web ] & the other is a computerised cam program. The 128 rule is for determining LSA for parallel valve heads in general & works for CRs of between 9.5 -11:1. For splayed valve heads like the BBC, 131.5 is used instead of 128. Correction factors are used for higher CRs & blowers etc.
Until I can find someone who has tested more cams than DV [ no luck yet!] I have been & will continue to follow his advice.
In his Chev books, he says if you want a smoother idle/more low end, you do NOT widen the LSA, you reduce the duration. Yes, might be in a Chev book, but a Chev is just an air pump...like a Ford or Mopar.
Click to expand...

Well, the one rule I've learned through my own experience says that's there is no one rule for anything.
 
PIE sells a 408 Stealth Long block that is nearly identical to my set up except for a 10.5:1 compression ratio. They run a 226/230 .565/.565 on a 110 LSA that is a 470hp@5200 510lb@4300.

That don't seem too bad, the cam Comp spec'd for me should be in that ballpark I would guess.
 
Well RRR, there is one rule that works & is invariable & that is this one: the right cam costs the same as the wrong one...
Not my quote, from DV.
That is why I try to find people who have had success with cam selection, rather than select from a cam catalog, or get 'advice' from a phone jockey reading from his/her companies computer choices.
 
Bewy said:
Well RRR, there is one rule that works & is invariable & that is this one: the right cam costs the same as the wrong one...
Not my quote, from DV.
That is why I try to find people who have had success with cam selection, rather than select from a cam catalog, or get 'advice' from a phone jockey reading from his/her companies computer choices.
Click to expand...

No argument there!

That said, there can be "PLENTY" of "RIGHT" choices. Nobody does anything the same.
 
Well, this is what I was able to gather from a few phone calls I made yesterday.

Hughes recommends upgrading springs and going with a 230/234 .565/.571 on a 108 LSA and to mil the heads .030

Howards suggested .507/.533 221/225 on a 112

Brian was out when I called IMM. Lunati never answered.

Seems like everyone has a little different opinion.
 
Bewy said:
Well RRR, there is one rule that works & is invariable & that is this one: the right cam costs the same as the wrong one...
Not my quote, from DV.
That is why I try to find people who have had success with cam selection, rather than select from a cam catalog, or get 'advice' from a phone jockey reading from his/her companies computer choices.
Click to expand...
I’ve got a few of Vizard’s books, have read many of his articles, and and would say I’m a student of his. What he says about calling for cam recommendations in general is true. His methods for selecting your own cam do work, and in many cases your own results can be much better than some of the places you call or send in a request online to. And, you will have at least a good idea of where you should be on a cam if you do call or send in a request. My advice is to call and ask to speak to the upper echelon guys like Eric Bollander at Howard’s, Tim Goolsby at Bullet (as many here have recommended, I’ve spoken to him, very smart, sharp) among other long timers with other companies that many here mention. You have to strive and ask to talk to the head cam guys at any of these companies, have a name, and insist and not just settle for, fall in the lap of newbies or less experienced. It’s like when you go to the doctor, or the ER. You don’t want interns, or trainees working on you trying to stick an IV in your arm or the like. You want Grandma! Been at it for decades, knows what they’re doing. :thumbsup:
 
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