Kicking cam numbers around...

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Revhendo

Revhendo

Master ACME Tech
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OK, so I am just looking for ideas on cams.
I had a solid flat tappet in my stroker 340, 4" crank, .020 bore. I loved this cam in this engine and it had power to spare in my 73 Roadrunner. This is the engine going into my Valiant, but after wiping out the lobes on two of these cams, I am going with a hydraulic roller cam. I have the lifters already and they are very pretty, so they are staying. I am looking for ideas on camshafts/profiles that will give me similar performance to what I had.

View attachment IMAG0074.jpg

What do you all think?
 
Did you have those cams nitride? Comp told me that will help with flat tappet cam life. I don't think the cost is much from them.
 
That cam must have been a stump puller in 4" combo. I'd look at hyd rollers in the [email protected] range,but depending on the complete combo I might change my mind. Call Tim @ Bullet cams and tell him Some SB mopar guy in FL sent you. He'll get it and grind you a cam that will work great for your application.
 
It's a little bigger than mine (@ 50, 231/239 dur .535"/.550") but I'm using stock stroke. You might wanna bump up a little because that 4" stroke is gonna suck a lot of cam.
 
I missed you already have the roller lifters, my bad, never mind on the nitriding
 
goldmember said:
That cam must have been a stump puller in 4" combo. I'd look at hyd rollers in the [email protected] range,but depending on the complete combo I might change my mind. Call Tim @ Bullet cams and tell him Some SB mopar guy in FL sent you. He'll get it and grind you a cam that will work great for your application.
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I'll have to keep that in mind. I have Donny Johansen on tap for a custom grind if my "engine guy" gets around to it.....

1970Duster said:
It's a little bigger than mine (@ 50, 231/239 dur .535"/.550") but I'm using stock stroke. You might wanna bump up a little because that 4" stroke is gonna suck a lot of cam.
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This cam worked great. Rowdy idle but not obnoxious or uncomfortable. Pulls like a fricken freight train for as long as you would like. It has a torque curve like a table top. I could see it being a bit snarky in a stock stroke engine.

Vitamin c said:
I missed you already have the roller lifters, my bad, never mind on the nitriding
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LOL, no worries. I'm waiting on the heavy lifter comments.....
 
Mopar to ya has a Comp 240-ish at .050 hyd roller,in a 4 inch arm small block.Says he likes it.
 
Revhendo said:
OK, so I am just looking for ideas on cams.
I had a solid flat tappet in my stroker 340, 4" crank, .020 bore. I loved this cam in this engine and it had power to spare in my 73 Roadrunner. This is the engine going into my Valiant, but after wiping out the lobes on two of these cams, I am going with a hydraulic roller cam. I have the lifters already and they are very pretty, so they are staying. I am looking for ideas on camshafts/profiles that will give me similar performance to what I had.

View attachment 1714617662

What do you all think?
Click to expand...

We use something like 242-248 on a 108 lca and .600 lift w/ 1.6 rockers if the heads are decent.
 
ou812 said:
We use something like 242-248 on a 108 lca and .600 lift w/ 1.6 rockers if the heads are decent.
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I won't readily admit to how much I have sunk into my stock heads. Let's just say that Juan Mendoza did a really nice job with my money. I already have the Comp Cams Pro Magnum roller rockers at 1.5.

Other fun facts:
Diamond pistons, zero decked, 10.25 CR ±
"I" beam rods
balanced within an inch of it's life
Holley Strip Dominator intake
Proform 750 vacuum secondary carb.

Tidbits,
Tim Deal built 727 with a "loose" Continental converter. (Worked awesome, ain't changing it)
489 case 8&3/4 with a 3.55 sure-grip by J&S Gear.
 
Rev,Mendoza did the work? Nice .Man has Wally's lying around every where.
 
With the low comp and " loose" (what ever that means) converter,no info on the weight and 3.55 gears you don't need a bunch of cam. With only that info(and the vaccum carb single plane intake,yuck) and no head info, I'd stay mid 230's @.050 but since it's not a race but mild street car you could go bigger and you'd never know the difference.
 
What's wrong with the same grind, just on a roller?
 
Abodybomber said:
Rev,Mendoza did the work? Nice .Man has Wally's lying around every where.
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Yeah he does, you just have to make sure one of his cats doesn't hitch a ride in the box when you pick stuff up... :D

goldmember said:
With the low comp and " loose" (what ever that means) converter,no info on the weight and 3.55 gears you don't need a bunch of cam. With only that info(and the vaccum carb single plane intake,yuck) and no head info, I'd stay mid 230's @.050 but since it's not a race but mild street car you could go bigger and you'd never know the difference.
Click to expand...

Low compression? Seriously? Have you seen the swill they pass off as gas here in Cali? I'm surprised my Zippo doesn't ping.

In my neck of the woods, a "loose" converter has a higher stall than stock, doesn't drag the engine down at idle, flashes nicely but isn't a full high stall race converter. This is a "mild" street car after all. I don't remember the numbers on it, it was done awhile ago and I'm getting older.

As far as the thoughts on the vacuum carb and the single plane intake, all I gotta say is that when I first put it together I was running a Thermoquad on that intake. The bowl finally gave up on me, hence the new carb. (If it didn't work, I wouldn't have kept it)

Thank you for your recommendations, but I think it might be a little low.
 
RustyRatRod said:
What's wrong with the same grind, just on a roller?
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I was/am under the impression that with a hyd roller you had to take into account how the lifter actually follows the lobe. Kind of like why hydraulic and solid flat tappet cams aren't the same.
 
Revhendo said:
Yeah he does, you just have to make sure one of his cats doesn't hitch a ride in the box when you pick stuff up... :D



Low compression? Seriously? Have you seen the swill they pass off as gas here in Cali? I'm surprised my Zippo doesn't ping.

In my neck of the woods, a "loose" converter has a higher stall than stock, doesn't drag the engine down at idle, flashes nicely but isn't a full high stall race converter. This is a "mild" street car after all. I don't remember the numbers on it, it was done awhile ago and I'm getting older.

As far as the thoughts on the vacuum carb and the single plane intake, all I gotta say is that when I first put it together I was running a Thermoquad on that intake. The bowl finally gave up on me, hence the new carb. (If it didn't work, I wouldn't have kept it)

Thank you for your recommendations, but I think it might be a little low.
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LOL OK How many 4" street strip builds have you done? Made 10000's of passes over 30yrs? Take your pick. LOL glad you got rid of the TQ carb.LOL good luck to you.
 
goldmember said:
LOL OK How many 4" street strip builds have you done? Made 10000's of passes over 30yrs? Take your pick. LOL glad you got rid of the TQ carb.LOL good luck to you.
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Damn, you caught me, I just snuck in from the Kawasaki Riding Mower forums.
 
OK,just through a dart at the cam page,maybe you'll get it right. LOL This started with some giving (both good and WAG'es ) and now it's just gone down the tubes. I'm sure you'll be one of those that I run into at the track with a combo that runs like azz,but I'll keep grinning ear to ear,while you keep guessing what to change next.
 
goldmember said:
OK,just through a dart at the cam page,maybe you'll get it right. LOL This started with some giving (both good and WAG'es ) and now it's just gone down the tubes. I'm sure you'll be one of those that I run into at the track with a combo that runs like azz,but I'll keep grinning ear to ear,while you keep guessing what to change next.
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See, here is the problem as I see it. I don't have a problem with you or your advice, though it wasn't even a half answer. I have a problem with your arrogance and attitude. Nowhere did I say I was building a track car. In your simple singlemindedness you just went there and assumed that everything revolves around the way your narrow mind works. If you had questions, you should have asked. You didn't. You flung your self possessed superiority like a monkey throws it's shyte from behind the bars of a cage.

Trust me pal, when I build a car with the purpose of running at the track, you will be going home early.
 
No cage here just the net. I told you any of the cams listed would work,how's that single minded? Your reading into things,I do too,and yes I can see that you are lost. Simple really.Last post by me so go ahead and stick something silly up as a response. Later
 
Roller cams (hyd or solid) bring into the power curve sooner and keep you there longer then a flat tappet cam. So even with the same grind cam as a roller you'll be getting more out of it but because it is an hyd, you can't spin it as high as your old solid flat tappet.
 
1970Duster said:
Roller cams (hyd or solid) bring into the power curve sooner and keep you there longer then a flat tappet cam. So even with the same grind cam as a roller you'll be getting more out of it but because it is an hyd, you can't spin it as high as your old solid flat tappet.
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I thought about the hydraulic part for quite awhile before I pulled the trigger on the lifters. It came down to how often I actually spent in the upper rpm with the engine and what I intended to do with the car when it is all together. The cast crank and I beam rods give up some high rev confidence, but spins up wickedly fast. The old cam was all power through the midrange and stupid fun in my pig of a 73 Road Runner (not light). There really wasn't any need to go above 6K with it and I can't honestly say it really spent any time above 5.5K......
 
Do you know what the heads flow? I don't know the guy you mention, don;t put much faith in names, and know plenty that spend a lot of money and get crap. No offense meant - I'm in CT and not a pro drag racer. So - in terms of a camshft choice I really need to know the flow and valve sizes on the heads, preferably not just peak flow because you'll never be in that range... I can say the intake is a poor choice. If you have it that's ok. But I'd spend on replacing that if the heads can flow any real numbers.
 
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