Mild 383 Cam - Help me choose

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Dart_440

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I'm planning to order a new cam today and I'm still undecided which I should go with.

I have a 383 that is 30 over, rods and mains are 10 over. Pistons are flat tops I don't know much else about them. Stock closed chambered heads with headers, RPM intake, 700 holley and pertronix distributor and ignition . 3.73 gear. It has a 727 with an unknown stall.

I installed the comp cams 268 about 3 years ago but the motor sat. When I finally got it up and running I smoked a lobe. So this is my second chance to pick the right cam or redo it with the same cam. I'm looking for something sounds pretty mean yet is tunable and still streetable.

I'm considering going with the same comp cams 268.
21-223-4(Single Bolt) - Xtreme Energy™ Hydraulic Flat Tappet Camshafts

or the Lunati 10230702
Voodoo Hydraulic Flat Tappet - Chrysler 361-440 262/268 - Lunati Power

Please let me know your thoughts or if I'm headed in the wrong direction

thanks,
Bryan
 
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the comp cam is it-a modern version of the 383-440 magnum cam. the lunati is too mild, and the 112* lobe seperation is more than what your combo wants
 
I like the Voodoo. I ran a Crane with just a little more duration (222/234) in a stock stroke 400 and it worked very well, but I had 3.91 gear and a bit more convertor. The same cam I ran is still available as a Summit house brand.
 
qkcuda said:
I like the Voodoo. I ran a Crane with just a little more duration (222/234) in a stock stroke 400 and it worked very well, but I had 3.91 gear and a bit more convertor. The same cam I ran is still available as a Summit house brand.
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Great thanks for the input.. I'm gonna look into it.
 
Our shop just finished removing a comp cams 268h 21-215-4 from a build we did. nothing wrong with it, it just wasn't enough of a "there's a cam in that" type of sound and idle characteristics. We chose the comp cams 21-224-4 and now he is a way more happier guy. It sounds good and responds good. The 268 was just too stock like for this build. 383 ,L2315NF30 pistons ,zero decked, 906 heads 32-891d springs , Mr Gasket steel 1135g head gaskets. and the rest.
 
Actual compression ratio would help as well as knowing the converter in it or actually, if your willing to change it out for a known stall converter. Also, what tires are planned to be run? The diameter should be known.

You have a decent gear. If the tire is t overly large, you could run a decent size cam. As large as a [email protected] without shorting yourself on gear. Again, a converter to match allows it to wake up.
 
you might check out the Hughes whiplash cam.
 
I am running an old 230 Hughes FT hydro (HE3038AL) in a 367. It Is a great street cam, But there is so little lope in it, that you can barely hear it. It likes lotsa compression tho. Specs are ; 276/286/110 lift of .549/.571 with 1.6 arms.
I run it with a stick, and it's a dump it and go deal with a 10.97 starter gear, so I don't think it would take much of a TC to pull it, partly on account of you got a few cubes on me. And partly on account of the Torque multiplication going on in the TC. And partly on account of even the stock TC takes off at a higher rpm than I do.
And partly on account of those 383s are like jackhammers.....:)
 
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For off the shelf the Comp DEH265 would be good.
 
rumblefish360 said:
Actual compression ratio would help as well as knowing the converter in it or actually, if your willing to change it out for a known stall converter. Also, what tires are planned to be run? The diameter should be known.

You have a decent gear. If the tire is t overly large, you could run a decent size cam. As large as a [email protected] without shorting yourself on gear. Again, a converter to match allows it to wake up.
Click to expand...

I have 26" tires. I would like to swap out the converter in the future but it might be a while.
 
do you want the car to perform well on the street or the quarter mile.
"sounds mean" usually not a good street performing cam
 
ir3333 said:
do you want the car to perform well on the street or the quarter mile.
"sounds mean" usually not a good street performing cam
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Yeah I hear ya.. Honestly I want to be able to tune it and drive 500 miles a year on the street. But I'm hoping its no slouch on the track as well. I guess I'm looking for something that's gonna push the limits of both.

I just pulled the box of the cam I had in it. I was wrong. It's the comp cams xe274. It had a crazy great sounding idle but ran a little rough, never really had it going long enough to try it out on the street. Wondering if I should try that cam again?
 
JmhO; but streeters might want to concentrate on 1/8 type performance, and,of course quick 60fts, are a hoot
60fts are not THAT big of a deal, since most of the time, the hammer drops at 30ish mph and is done by 45mph, or maybe 55/60. So the engine needs to pull from 30 to 55 say. With 3.73s and a 2.45 low, and 27s, this is 3400rpm to 6250. So a 292/508/108 is a total big-azz waste. Yeah I found that out the hard way. 420 hp at 70 mph helps nothing, if the race is over at 55mph.
So enter the 383
in the above scenario,you need to make power at 3400 to 6250; so the horsepower peak could be about 400 to 600, (depending on headflow and appropriate cam) lower than 6250, so say 5700. Well ain't that sweet.That would be a 235* to 245* cam @.050,(in a 360) depending on the headflow, and how badly the exhaust gets strangled in the A-body.In the 383, Ima guessing the 235*would be the hot ticket.But not with long lazy ramps! The shorter the ramps the better. Sub 44* is good.Sub 40* ramps are better for bottom end. So then 235 + 44 = 279* advertised. Or even 235 + 40 = 275* advertised; but now you are getting into solid lifter territory.The thing to remember here is "fast rate of lift". Some call it hi-intensity.The fast rates will leave you some Dcr to burn rubber off the line with. And with a stock TC, you will need you some Dcr.
 
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The XE274 has specs of 274/286/110/in at 106 for an ICA of 63*. The 050 #s are 230/236, and lift of .520/.523....These then are 44* ramps, so looking good!
This will require a Static CR of 10.3 to net a Dcr of 8.25/165psi
At these numbers your 383 will have a strong bottom end, to use the stock TC and your 3.73s.
If you slap that cam into a 9/1 engine you will likely be very disappointed....the Dcr will be around 7.23/139psi. I think this will barely squawk the 275/60-15s,with your parts.But again, at 30 mph the Rs are 3385 with 3.73s so the stockTC is out of the picture, and the engine is starting to make torque.By 4000 or so the torque should be peaking so by 35mph she is pulling pretty hard.(Of course not as hard as if it had a 10/1 Scr)
The 286* exhaust degrees makes the install flexible, and will help to exhaust in the A-body chassis.I would slam that puppy in there. It is the right cam for street.
But it wants at least 10/1 compression ratio to be strong on the bottom.
The difference between 165 psi and 139psi is very dramatic off the line, and with a stock type TC. I think it would be better if you had a 2800 and 3.23s, than a 2200 and 3.73s......... But no matter, 3.73s are excellent for street.
So the thing to do now is calculate the current compression ratio.
If the engine is in the car there is no good way of doing that, short of pulling a head and measuring it.
Outside of that, you could stab the cam in with just two lifters and do a compression test on that cylinder. I would be looking for 160psi, which is 8.00Dcr on a 10.0 Scr...For me that would be non-negotiable minimum.I would adjust the Scr to get it or live with the bottom end.
But Ima thinking with 3.73s, that engine is gonna spool up a little faster, so say you had at least 150/155psi, I might take a chance. And if you are running 245s It might be good even at the aforementioned 9/1;cuz even a teener can spin those, and if your spinning, the stall don't matter much.
 
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your combo begs for the hughes whiplash cam. check it out. nasty sounding, maintain cylinder pressure, and bottom end torque.
 
Fishmen
The whiplash cam appears to be very nearly the same, as the XE274, when the 274 is advanced to 103-ICL. I'm not sure it's worth the price of the kit to notice such a small difference, since he already OWNS the XE274
The whiplash cam has specs of 229/242/107 in at 102 and lifts of .518/[email protected]
I extrapolated the .050 numbers,assuming Hughes fast rate lobes to come up with an approximation of the advertised numbers as 274/286/107. With those numbers and an Scr of 9.0,this yields a Dcr of 7.47/145psi
Compare that to the Comp XE274 specs of 274/286/110. The 050 #s are 230/236, and lift of .520/[email protected] at 103, I get Dcr of 7.40/144psi

I know the numbers are not always the final say,so, perhaps you have the experience that I lack, so what say you? Do you think it's worth it to run a 107 over the 110, in this application?
 
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Well, if you extrapolated, then that's it. We may as well close the thread.
 
Just remember it's a 383 and not a 440.
You do not need a large cam to make it work.
The original Comp Cam you chose will serve you very well.
Tom
 
IQ52 said:
Bobby/Roberto, when I met you at the NATS I knew YOU were a closet extrapolator. Are you still afraid to come out?
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Rusty, IQ52 .... you guys gave me the first laugh of the day. AJ, you extrapolation is off because the XE274 doesn't have .520, .523 lift with a 1.5 rocker ratio.
 
Thanks for all your opinions and help. I will let you know how it goes. I went with the same one I had in there which was the 274. It should be up and running in a couple weeks. Thanks again!
 
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