Custom Grind or Off the Shelf

[451Mopar]

A roller cam F.A.S.T. build 383 stroker engine with 12+ compression is not going to have much in common with the cam for this.

Wrmrider summed it up well. Pick the better cam that fits. Set your bench mark high.

JMHO. If you want to start with a high bench mark I would call Lunati and have them change the 702 to a 110 lsa. Not the 112 Lsa shelf 702 cam..Lunati does that for free, only down side is paying for shipped, versus free shipping from the parts warehouses.

The Lunati’s is the more modern profile of the two cams your looking at. Probably similar in peak power, the difference would show up more in the average power.

451Mopar, LOL, that looks like the valve to piston marks on one of our 383s. Ours happened somewhere around 6500-7000 with a MP484 cam.

That little goof of bending the valves was the start down the path to my first 451 stroker. I originally bought the B-1 B/S heads to replace the 906 heads with the bent valves, but I really could not take advantage of the higher flow at high lift because of the piston to valve clearance problem of no valve reliefs in the pistons.
At the time (around 1992) I moved to a new city and did not know any machine shops, so I called Muscle Motors, talked to Chuck Senatore, and had them build me a short block to drop the heads on.

On the Lunati cams, I like them too, and they are usually a bit less expensive. The Voodoo series does use a 3-bolt cam gear for the timing set, vs the standard single bolt timing gear setup.

 

[wyrmrider]

good
let us know
IDK about 110 with stock exhaust I'd use whatever jones recommended

Jones wrote from 2011 speedtalk thread
Most people will look at the .200" duration to try and figure out which one's got more area, but cam companies have ways of manipulating those numbers to make the cams look more aggressive."

"Really, the only way to know for sure, is to look at the duration at every .050" of VALVE lift, with the lash set, and compare.
This takes all the variables out, and shows you what the engine is really seeing."

which we would do for a "heads up" build
but here .200 has to do

i would also not be looking for a bigger lift asymetrical lobe for the exhaust
but we have what we have
if the 267 crower is MTO? ask shaun if that's rhe best lobes they have for you
Thanks for the real world experience on the 271

My usage is many years ago with stock heads
I did have Crower grind a cam that had to sound and idle and vacuum stock
we went shorter seat, [email protected] and .525 lift ( or was it .505 I forget) 112LCA
This was a matching number 383 superbird -440 crank-with ported stock heads and manifolds cleaned up, forged custom quenchdome pistons 9.5 cr
not a budget build we used Isky dual springs set up tall fo less pressure 2.14 x 1,81 valves
Today I'd use beehives and lighter valves

 

[PRHeads]

He has an extremely good running 383 that runs in FAST. Low 11’s I believe in a 68 b body

I’m pretty sure that car was never run in FAST, but was running low-11’s in typical bracket trim.......with TRW flat tops and unported 906’s.......@3670lbs.

I also seem to recall one iteration of that same motor got dyno tested with 9.7:1, stock valve size bowl ported 346/452 heads(one of each), a SFT cam, RPM intake, 4779 carb...... and HP manifolds.

It made 419hp.

 

[LowDeck451]

A roller cam F.A.S.T. build 383 stroker engine with 12+ compression is not going to have much in common with the cam for this.

Wrmrider summed it up well. Pick the better cam that fits. Set your bench mark high.

JMHO. If you want to start with a high bench mark I would call Lunati and have them change the 702 to a 110 lsa. Not the 112 Lsa shelf 702 cam..Lunati does that for free, only down side is paying for shipped, versus free shipping from the parts warehouses.

The Lunati’s is the more modern profile of the two cams your looking at. Probably similar in peak power, the difference would show up more in the average power.

451Mopar, LOL, that looks like the valve to piston marks on one of our 383s. Ours happened somewhere around 6500-7000 with a MP484 cam.

Dodge Bro’s said.... “Lunati will change lobe center free of charge...” I like that idea since everyone seems to prefer 110 to 112, and all (almost all) the shelf cams are 112 (for some reason?). I called Lunati and asked about that, they said there would be a custom grind charge, about $179 for the cam, compared to shelf cost of about $140. Price for the other customs I’ve shown are around $250. Price isn’t the main concern, but this seems like a simple solution ‘for me’ at this point.

 

[wyrmrider]

with stock exhausts just use 112
Crower? I'd like to her what Shaun has to say
Howards for a custom exhaust lobe
real soon now cams are going to be ground from computer files not masters so there should be little money for changes
chances are the shelf cams are ground in Detroit not Mississippi
that will change with all computerized grinding
The firm that one good cam picker uses has 6 Landis grinders going 24/7

 

[LowDeck451]

with stock exhausts just use 112
Crower? I'd like to her what Shaun has to say
Howards for a custom exhaust lobe
real soon now cams are going to be ground from computer files not masters so there should be little money for changes
chances are the shelf cams are ground in Detroit not Mississippi
that will change with all computerized grinding
The firm that one good cam picker uses has 6 Landis grinders going 24/7

Aw man, yer killin me! 112 now? I don’t think anybody recommended a 112, unless I just went with a shelf cam. I’m talking about a Lunati 702 on a 110. No good?

 

[Curiousyellow71]

I like your plan. 702 on 110
My #21 post
[QUOTE="Curiousyellow71, post:
With exhaust manifolds I think I would do 110 lsa. .[/QUOTE]
702 is pretty mild on 112. 110 will give the 383 a bit more bite.
GetRdone.Lol

 

[Dodge Bros]

If you were to use the Crower, I think Wrmrider would be correct, the Crower probably should be 112 lsa.

The 112 lsa for a Crower and a Lunati voodoo needing a 110 lsa is a difference in lobe profiles. The Lunati series profiles manage reversion and intake charge exhaust dilution with an asymmetric profile, from .006 to .050” it has 45* degrees of intensity. I don’t recall the exact span, but I think it is 20-21 degrees span on the opening ramp and 24-25 on the closing. The difference increases more yet at the lower lifts like .004. I think the pan is closer to 8*. It changes a lot of aspects when the cylinders are filled.

All the Crower hft’s I have had used a symmetric profile, lsa & acceleration rate of the profile is mostly what they use for managing the cams overlap. I assume that 267 Crower is ground the same. They have their place, if the engine had more compression I probably have picked the Crower or a bigger Lunati. If the 267 Crower has an intensity of 47* from .006 to .050”, it has 23.5* on the opening ramp, 23.5* on the closing.

Two cams with the same specs, but one symmetrical and the other asymmetrical, for the same idle the and top end rpm band the lsa needs to be wider on a symmetric cam. 112 lsa on voodoo is pretty wide in a 383, 702 w/112LSA is more of cam for a 3.75” stroke engine. Jmho

 

[LowDeck451]

If you were to use the Crower, I think Wrmrider would be correct, the Crower probably should be 112 lsa.

The 112 lsa for a Crower and a Lunati voodoo needing a 110 lsa is a difference in lobe profiles. The Lunati series profiles manage reversion and intake charge exhaust dilution with an asymmetric profile, from .006 to .050” it has 45* degrees of intensity. I don’t recall the exact span, but I think it is 20-21 degrees span on the opening ramp and 24-25 on the closing. The difference increases more yet at the lower lifts like .004. I think the pan is closer to 8*. It changes a lot of aspects when the cylinders are filled.

All the Crower hft’s I have had used a symmetric profile, lsa & acceleration rate of the profile is mostly what they use for managing the cams overlap. I assume that 267 Crower is ground the same. They have their place, if the engine had more compression I probably have picked the Crower or a bigger Lunati. If the 267 Crower has an intensity of 47* from .006 to .050”, it has 23.5* on the opening ramp, 23.5* on the closing.

Two cams with the same specs, but one symmetrical and the other asymmetrical, for the same idle the and top end rpm band the lsa needs to be wider on a symmetric cam. 112 lsa on voodoo is pretty wide in a 383, 702 w/112LSA is more of cam for a 3.75” stroke engine. Jmho

Thanks, I understand that explanation.
Wyrmrider, thanks for your help too, I really do appreciate it. I haven’t been able to absorb all this information at the pace this thread was moving, but I did learn a lot. Thanks again everybody.

 

[wyrmrider]

what dodge said
I DK about the extra expense
I'd still check howard if lunati is going to charge extra
asymetrical does manage reversion better than symetrical for the same overal duration lobe
not a fan of asymetrical on the exhaust though but not much we can do about it

 

[LowDeck451]

Well, sorry guys but I goofed on my comp. ratio calc. I’m at 10:1, not 9:7. Don’t know how, I know it ain’t rocket surgery but, CC’d everything again, spot checked, 10:1. California 91 octane premium here, detonation my big concern.
‘69 Barracuda 383 Street/driven to track
727 2500 stall
3.55
Perf. RPM intake now

Talked to Tim at Bullet, he says same rec.-
230/234 108/104

Talked to Shane at Crower- #32243 282/292 228/236 112 Said he had this cam in a 10:1 400 in a Dart and liked it. Doesn’t think the 271hdp ([email protected]) is safe against detonation.

Filled out a Lunati cam rec. - came back #703.
268/276 226/234 110

I’m leaning toward the Lunati. The Crower seems a little long for the little 383?
Anyway, Thanks again guys.

 

[POMONAMISSEL]

you need to waste off some of that cr for calif gas , 383 is a rev'r . spin it up , and if you have alum heads it won't be a worry .

 

[BSB67]

If gas is an issue, the Crower will be the least detonation prone of the three.

 

[m79ded]

Howards 230-236 on .904 design would be a great choice, My buddy Tom @ TK tried it and got great results with it. Much better than that Lunati 268/276 226/234 110

 

[LowDeck451]

you need to waste off some of that cr for calif gas , 383 is a rev'r . spin it up , and if you have alum heads it won't be a worry .

Thanks. Iron heads and exhaust manifolds.

 

[LowDeck451]

If gas is an issue, the Crower will be the least detonation prone of the three.

Noted. Thanks.

 

[LowDeck451]

Howards 230-236 on .904 design would be a great choice, My buddy Tom @ TK tried it and got great results with it. Much better than that Lunati 268/276 226/234 110

That’s the .531/.547 - 110/106 right? I believe you and all, but just don’t want that much lift on stock rockers, and I don’t think my pocket ported 516 heads can use it all. Thanks though.

 

[POMONAMISSEL]

fly cut your pistons thats to much cr for cal gas . 9 to 1 at best . or alum heads can fix the heat issues you will have , or a cam that wasted all the stroke or you can go so fat on fuel it cools it off from pre ign from hot parts setting off the fuel prior to the plug firing .

 

[LowDeck451]

I was looking at Howard’s lobe list on their website and saw a couple lobes in the ‘Aggressive .904’ section I thought would be good for my combo (though these don’t have as much lift and .200 as the Howard’s list Dodge bro’s posted in post #106).

I called and left a message with Tim Stoddard at Howard’s to talk about their Lift Rule .300 cam rec. mistake, he didn’t call back so I talked to JJ. Gave him my info...
‘69 cuda
10:1 383, ex. man.
3.55
auto, 2500 stall
He suggested 269/277 215/223 112 .445/.465
I asked about 3hf227330
274 [email protected] [email protected] .495 intake and...
3hf231333
278 [email protected]. [email protected] .499 exh. on 112
He thought for a sec and said “Your close, yeah, that’ll work.” $159 cam $105 lifters
So, barring any glaring mistakes, I think that’s what I’ll go with. Not the fastest lobes, not a LOT of lift but I think that’s ok. Thanks Dodge Bro’s, wyrmrider, PRH, BSB67, curious yellow, m79ded, mopar451 for your help and time. I really do appreciate it.

 

[m79ded]

I was looking at Howard’s lobe list on their website and saw a couple lobes in the ‘Aggressive .904’ section I thought would be good for my combo (though these don’t have as much lift and .200 as the Howard’s list Dodge bro’s posted in post #106).

I called and left a message with Tim Stoddard at Howard’s to talk about their Lift Rule .300 cam rec. mistake, he didn’t call back so I talked to JJ. Gave him my info...
‘69 cuda
10:1 383, ex. man.
3.55
auto, 2500 stall
He suggested 269/277 215/223 112 .445/.465
I asked about 3hf227330
274 [email protected] [email protected] .495 intake and...
3hf231333
278 [email protected]. [email protected] .499 exh. on 112
He thought for a sec and said “Your close, yeah, that’ll work.” $159 cam $105 lifters
So, barring any glaring mistakes, I think that’s what I’ll go with. Not the fastest lobes, not a LOT of lift but I think that’s ok. Thanks Dodge Bro’s, wyrmrider, PRH, BSB67, curious yellow, m79ded, mopar451 for your help and time. I really do appreciate it.

Your welcome let us know how it works