340 cam replacement

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kbduster

kbduster

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71 steel crank 340 with factory 10.5:1 pistons, later LA360 factory heads, air gap, 650 speed demon, tti's 2.5 w/Xpipe, 3k stall, 3.91's in my 72 duster. I bought the engine newly built and together. I was told it is a lunati .480 cam. That's all I kmow. Any recommendations for an off the shelf cam that will give me the best performance with using the springs I have. Need to get running again quickly, so just want to swap cam and lifters..
 
"using the springs I have"

I looked into my crystal ball and cannot see what springs you have.
 
This thread may go on for years. We like to talk about cams around here and 99% of the recommendations are right but they are all different. Good luck. Oh, I recommend you use what ever springs the cam company says.
 
I'll be the one to recommend a 273 2bbl cam and we can work up from there. Vs the 575 lift. 1.7 rocker arm solid lifter cam this post is going to go towards. Lol
 
3000 TC? 3.91s, 10.5 Scr
You need the 284/484/108. You'll make a bunch horsepower at rpms you almost never drive,but it'll sound pretty racey.And once it stops spinning you'll have a blast. Make sure your posi is adjusted up tight.
 
Assuming the springs are matched to the cam, what exact Lunati cam is it?
There “Bracket Master” with .480 lift on both sides?
 
Thats the same cam i use in my 360, runs really strong and has a kick *** idle.
 
this might be a good spot for a 3/4 cam.
Sorry ..couldn't resist.What are your vehicle specs and how are you going to use it?
 
My buddy back in hi-school had one of Them 3/4 race cams in his 69-340 Swinger. It had a kick-azz idle thru his cheap-azz headers.He had all the good stuff.
But my stock 70Swinger 340 still whupped his azz.
Well I had 4.10s and custom slapper bars,lol.
And he wasn't actually a buddy..........Just another tic on the checklist.
At the track tho,he was both faster and quicker.................on his slicks.
 
And I'll be the one to recommend the engine be dismantled and inspected for damage. A "newly built and together" engine that "wiped a couple of lobes" is going to have an awful lot of trash fed through the bearings and up the sides of the piston skirts! Please take it apart.
 
Why did it wipe a few lobes? There is typically a reason other than lack of zinc in the oil. Adjustable rockers set to tight? Retainers hitting the guide tops? New cam with used lifters? Too long of push rods?
 
dano said:
Why did it wipe a few lobes? There is typically a reason other than lack of zinc in the oil. Adjustable rockers set to tight? Retainers hitting the guide tops? New cam with used lifters? Too long of push rods?
Click to expand...

Wrong springs perhaps?
 
Max1196 said:
And I'll be the one to recommend the engine be dismantled and inspected for damage. A "newly built and together" engine that "wiped a couple of lobes" is going to have an awful lot of trash fed through the bearings and up the sides of the piston skirts! Please take it apart.
Click to expand...

I had to agree with this, because I bought a car with ONE bad lobe and lifter and it made a mess of the lower end bearings.
The consensus here for the most part was the oil filter would catch most of it, but that obviously didn't take into account the shower of particles rinsing down on the top of the crank and rods and what got run through the oil pump also destroying it.
It trashed two main bearings and two rod bearings right below that lobe.
I was under the impression the oil flowing out of those bearings would have protected them, but obviously not.
 
This thread is solidly off the rails and springing into chaos. 3/4 of the time it is only 1/4 on track and 75% of the rest it's fullofchit.. By now the OP is 1/3 bonkers, 1/4 hungry and 99% steaming hot under the collar. He's probably looking for his wife to help him forget he ever posted. And right after that he's gonna come and tear most of us new ones.I'm gonna go strap on a cushion cuz I'm a good little half-azzedBoyScout.
 
rumblefish360 said:
Whooopie cushion???

Extra large???
Click to expand...
Wow! All I was asking if anyone had opinions on a similar size cam....the wiped lobe was just an assumption from past experiences...Anyhow, I went with a comp magnum series .480/231°. Got all buttoned up and sounds the same. After a day of trying not to think about it, I dove back in and I found that a bunch of the pushrods are rubbing the tubes in the head...
 
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