SB 360 which cam

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petreed150

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Hello,I am building a 360 for my 83 d150 and need cam advise.360 has been bored 30 over with KB107 pistons,360 cast heads which has 9.8 comp and new mp heavy duty rockers.727 has been rebuilt and i want to use 2500 or 3000 stall with 3.91 8.75 rear.I looking at mp 484 or voodoo 494/513 60403 cam.Which one will be best?Any help would be appreciated!Thanks
 
That Voodoo is a nice grind.Idle better,more torque,most likely better mileage.(If that matters) The
.484 cam has a sweet lope!Makes power at the expense of driveability.Simply put,the Lunati will more overall power without the driveability problems.Me?I would go the Lunati of the 2.
 
Do you think it will be fine with the rockers and i little worried bout compression want it to work with 93 octane and what cfm carb which is gonna be holley dp
 
Yes,on both.The M/p .509 cam I have seen with stock rocker gear.I would check valvespring pressure and valveguide to retainer clearance.You did not spec the springs.As for octane,if it is 93 octane no sweat.The. stall converter lets the load off the engine untill lockup.That drops the octane need.
 
What cfm carb i have holley 650 dp and holley 750dp and springs aint got yet but everything is at machine shop i wanted to make sure that the voodoo would work with rockers first
 
Yeah heads are getting ported and i have eddy airgap and ld340 but think the airgap would be better.My machine shop says 650 but all the mopar guys i talk to says 750 and also need to know how to do lifter preload.Thanks for hanging in there with looking at the classifieds
 
I also would use the Lunati cam. Between the 2 intakes, I would run the Air-Gap unless your driving the truck in the cold. The LD-340 will have a good advantage in the cold.

I agree with your machinest on the smaller carb since the HP difference will only be about 10 HP on the big end. The larger carb, by compare, will be a little harder to tune, have less drivabilty, poorer gas mileage. This is only a marginal difference, but one that is there.

Since your running ported heads, the extra carb CFM would be a small bennifit.

The smaller carb will have increased velocity for better fuel atomization keeping torque up, excellent throttle response and best mileage will result.

With either carb you go with, tuning is of the upmost importance. If your going to go with the smaller carb, I myself have found good results with a stub stack from K&N and a open air cleaner and open top. This combo helps the carb breath better drawing air stright down from the top. (This actually will add a few CFM to the carb.)
Also a small note, if your driving in the cold weather, a full stock aircleaner is the best idea with a heat stove to it to help warm up the engine/carb for drivailty. You can get a 340/360 4bbl. air cleaner with a K&N or equal filter easy enuff.

I have run this combo of parts before. KB-107's @ zero deck and 2.02 J heads on 93 octane. If your pistons are below zero deck a little, the ratio will be slightly less and he octane requirement drops making it easier to fuel up and drive.

Lifter pre-loading is measuring the lifter being pushed downward buy the pushrod. There is alot of play in this area. IF the engine block was not decked, stock length pushrods will do. IF you want to measure with adjustable pushrods, look for a set of measuring pushrods with a marked shaft which will tell/show you the measurement as you adjust them.

Your looking for a min. of .020 lifter depressed downwards. Not more than .080.
 
hp is torque x rpm, so 750cfm will make more torque and through wider range than the smaller 600 carb after the smaller carbs initial 'snap' when u dip the throttle has past...... See the smaller carb is great for low speed part throttle, that is..for about a second or 2, after that.. the power is flat/flatter than the next step up=700/750.

This doesnt mean ''the bigger the carb, the better''..well actually to an extent it does in theis and many other cases...but, there is a point where too big, and u get poor low speed vac signal to the boosters and the mixture go's to crap till the rpms are high enough...and funny cause then at that point where it gets some rpms.. it will still make more power than the ''small'' carb.lol
There is a size range per cubic inch and rpm level, for your motor imo it's 600-800cfm. So if u would like it to still make torque at rpms over 5000...u should run at least a 700cfm carb,imo
 
The pistons are zero decked and where would the best place to find adjustable pushrods?Talked to machinest yesterday and he is wanting me to thank about xe274 cam with 488/491 cam.I get motor back at end of month so I have been on this motor about 2 yrs so i think i gonna get voodoo!
 
Voodoo & air gap. JMO When I pulled the 750DP off of my 10:1 340 Linati .480 cam w LD340 and put on a 650DP i noticed it seemed a little more throttle responsive down low, but the 750 was gummed up from our sweet gas.
 
if your going to use factory rockers i would go with the comp 280 480 magnum cam, no adjusting just bolt down and go, just from my experiance, but the others will work good to:blob:
 
1wild&crazyguy said:
hp is torque x rpm, so 750cfm will make more torque and through wider range than the smaller 600 carb after the smaller carbs initial 'snap' when u dip the throttle has past...... See the smaller carb is great for low speed part throttle, that is..for about a second or 2, after that.. the power is flat/flatter than the next step up=700/750.

This doesnt mean ''the bigger the carb, the better''..well actually to an extent it does in theis and many other cases...but, there is a point where too big, and u get poor low speed vac signal to the boosters and the mixture go's to crap till the rpms are high enough...and funny cause then at that point where it gets some rpms.. it will still make more power than the ''small'' carb.lol
There is a size range per cubic inch and rpm level, for your motor imo it's 600-800cfm. So if u would like it to still make torque at rpms over 5000...u should run at least a 700cfm carb,imo
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Exactly and it is which it is also why I recommended the smaller carb since 90% of driving is not in wide pen throttle, just part throttle. The power difference at wide open throttle is minor and mostly used for getting on the Hwy. or passing a car on the Hwy.

Considering it is a truck and weighing in more than a "A" body by a good some, I do believe the added snappy performance of the smaller carb would be good.

petreed150 said:
The pistons are zero decked and where would the best place to find adjustable pushrods?Talked to machinest yesterday and he is wanting me to thank about xe274 cam with 488/491 cam.I get motor back at end of month so I have been on this motor about 2 yrs so i think i gonna get voodoo!
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It's not so much adjustable pushrods but pushrod length checkers to measure the length and them have pushrods made.

Comp Cams, Hughes engines have these measuring pushrods. Do a search around to find one inexpensively.

I also was about to recommend that cam but decided to stay out of it.
 
petreed150 said:
Thats little too big but sounds like a wicked cam but dont know if i want to run my roller rockers!
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That was meant to be a joke. lol In all seriousness, I am building a VERY similar truck right now. I HAD decided on this cam P4529969. BUt I changed my mind, because mine has a 3.55 gear and I am not regearing. The above cam is a MP oval track solid. It's specs are .509/.509 238 @ .050" ground on 106 LSA. You will have enough gear for that cam and it will sound really shag nasty in your truck. I had two things against me. One, I am building a 318. Two, I am sticking with the 3.55. I think that little oval track solid would sound cool in your truck. That 106 LSA would sound wicked nasty.
 
There's a hydraulic cam perfect for Strokerscamps 318 on the way!(lol!)
 
Abodybomber said:
There's a hydraulic cam perfect for Strokerscamps 318 on the way!(lol!)
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Good Lord....and you know, there's this little voice in my head sayin DO IT, but I would be pullin it right back out. LMAO. I am goin hydraulic......just not THAT one. I think we're gonna save that one for a moderate 360 or a mild stroker........but the temptation is there to make a 318 stab. lol
 
Stroker,wasn't that bad!(lol!)Idled about 1200 in drive,choppy,with 4 inches of vac.10 to 1 408,w Eddys.Needed to work the 750s transition circuits a little more.
 
Would the xe274 have more power than voodoo!If it does I'll give it try,I know its a chevy cam lobe!I want to keep more torque but it should sound little more choppy!
 
I am gonna drive it all season as much as i can!Thinking bout reusing ld340,it is on my 318 now thats in truck!Runs descent!
 
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