104* or 108* ??

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Sportman

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Hello I am getting ready to begin assembly on my 408. block should be finished Wenesday. Here is what I am thinking, about cam istallation. Since the car is a street car only I am consideing advancing the cam 4* to give the motor better low end. Here is my combo.

9.2:1 comp
ported J heads w/2.02in/1.60ex
tti headers & 2 1/2 exhaust
4 speed
3:55 sure grip
27" tires
rpm air gap edelbrock 750 eddy carb
msd billet dis & 6al box

Cam MP 284/484 108* in Cent. 68 over lap ( I know there are better cams, but this is what I have to work with right now)

Would degreeing this in at 104* help the low end or should I just stay with 108? Street use only.

Thanks everyone you have been a great help!!
 
Sportman said:
Hello I am getting ready to begin assembly on my 408. block should be finished Wenesday. Here is what I am thinking, about cam istallation. Since the car is a street car only I am consideing advancing the cam 4* to give the motor better low end. Here is my combo.

9.2:1 comp
ported J heads w/2.02in/1.60ex
tti headers & 2 1/2 exhaust
4 speed
3:55 sure grip
27" tires
rpm air gap edelbrock 750 eddy carb
msd billet dis & 6al box

Cam MP 284/484 108* in Cent. 68 over lap ( I know there are better cams, but this is what I have to work with right now)

Would degreeing this in at 104* help the low end or should I just stay with 108? Street use only.

Thanks everyone you have been a great help!!
Click to expand...

Yes install it at 104icl. If you can only get 3° or 5° for some reason go with the 5°.
 
The lower it is for the stroker the better right Brian?
 
well....I look at the measured compression, and rpm range of all the parts. Plus....some cams work better advanced weather they are big or small. If he had 10:1 I would say run it straight up.
It will be a TQ monster either way!
 
On a 408? I see no reason at all to advance it. It's a very small cam for the stroke and heads. But you will want to degree it regardless to see if it's even manufactured close to right.
 
moper said:
On a 408? I see no reason at all to advance it. It's a very small cam for the stroke and heads. But you will want to degree it regardless to see if it's even manufactured close to right.
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Moper,are you saying that because of the size of the cam??..cause' i know the cam in my 416 .533/.552 was 4 degrees advanced...
 
241* @ 050 isn't very large in stock stroke engine , nevermind a 400+ cube engine.
 
I run a MP .474 cam in my 360. With that being said for your nice stroker motor I believe I would go with a modern cam or even a custom ground cam to match that engine combo pefectly. If I was going to spend that type of money in stroking it then I might as well spend a little extra on cam.

A roller cam would be nice.... with all the oil debate now a days.
 
stroked 340 said:
Moper,are you saying that because of the size of the cam??..cause' i know the cam in my 416 .533/.552 was 4 degrees advanced...
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Yeah, that's what I'm saying. Only going with the info given here...It's got a 4" arm which to me says big torque and more cylinder pressure anyway, even with a low static ratio. At the valve it's not going to have more than .465 lift and it's only open for a short time overall. I don't see much of a reason to limit an already challenged mid range and upper range power for torque with it. I know nothing about what you had so I really can't say anything about it.
 
stroked 340 said:
Moper,are you saying that because of the size of the cam??..cause' i know the cam in my 416 .533/.552 was 4 degrees advanced...
Click to expand...

The thing to consider is the lobe separation,the lunati has a 110 where the mopar has a 108,with the tighter separation and the big stroke it would'nt be very beneficial to advance the cam.
 
Given the tall gear and low compression it WILL be beneficial to advance the cam...I guarantee it!
Look at the rpm range of that engine with that gear in a driver....
 
ou812 said:
Given the tall gear and low compression it WILL be beneficial to advance the cam...I guarantee it!
Look at the rpm range of that engine with that gear in a driver....
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How much difference are you thinking?,I certainly respect you and your expertise but we are not talking a huge difference in cam timing,especially with the cubic inch.I ran the exact cam in a 360 with a similar build,when I degreed the cam I could not get four degrees advanced with the timing set so I settled on a 102cl with six degrees advanced,I ran it that way and then went to two degrees advanced with a 106cl.The car lost 5 psi cranking compression at the 106 centerline vs the 102 but ran a tenth quicker in identical conditions,for me that was a pretty small change over all.
 
Yeah not huge gains for sure but with only 9.2:1 I would shoot for more advance. With a tall gear you want brutal TQ to move the car and have it "feel" powerful and advancing that cam 4 or 5 degrees would do that.
I'd bet you could feel the difference and to me that's enough.

Like I said earlier, if the comp. was higher or the gears were lower then I'd agree maybe only 2° adv. or straight up.
 
SHE LIVES???? I got the 408 put back in the dart yesterday and fired her up. It was -14F outside so I just set the timing and pulled it outside for cam break in. I did degree the purple shaft cam in at 104* and everything sounds great. It has a slight lope to it but really sounds strong idleing. I am heading to Florida in a couple of weeks. I will be fine tuning somewhere a little warmer than here. I need to pick up a different carb (750) while down there. The oil is change and the dart is loaded on the trailer for the trip south, can't wait. Thanks for all of the advice, I will try to get a video up while down south.
 
Sportman said:
SHE LIVES???? I got the 408 put back in the dart yesterday and fired her up. It was -14F outside so I just set the timing and pulled it outside for cam break in. I did degree the purple shaft cam in at 104* and everything sounds great. It has a slight lope to it but really sounds strong idleing. I am heading to Florida in a couple of weeks. I will be fine tuning somewhere a little warmer than here. I need to pick up a different carb (750) while down there. The oil is change and the dart is loaded on the trailer for the trip south, can't wait. Thanks for all of the advice, I will try to get a video up while down south.
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You sir are a F**kin mad man!!! -14F, NO f**king way your going to get me to do that when its that cold. Nope not going to happen.
But now that you've frozen yourself doing this, you've earned those nice Florida temps!!! Have fun down there.
 
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