340 Engine Shake

-
This may be a little off topic. He also tested the vacuum with a guage and it's spot on with Fitech 10-11in.

Would you expect the vacuum to be that low with this cam? I swear when I talked to lunati on a cam recommendation, they said this one would have good vacuum with the setup I have.

View attachment 1715972578
For that cam 10-11 inches is pretty much normal
I would be more concerned if the vacuum reading was bouncing around like when your shaking starts.
I have had performance engines that performed and idled well with 5 inches of vacuum.
 
Ok, thanks gents. Sets my mind at ease. I am curious to what he finds when the intake is off. I found some horror stories on lunati lifters, figures. lol. @72bluNblu was one of them who had one fail out of nowhwere.
 
new lifters are hit or miss , vacuum seems about right for that cam think my 340 with similar cam had 13 vacuum so you are in the ballpark .
good luck
 
I would expect more, but that could be an issue of installed centerline or preload or ignition timing, pcv, etc.

Good point on the centerline. Was this cam degreed or just installed by lining up the dots on the timing set?
 
Ok, thanks gents. Sets my mind at ease. I am curious to what he finds when the intake is off. I found some horror stories on lunati lifters, figures. lol. @72bluNblu was one of them who had one fail out of nowhwere.

They offer two types, the 'standard' ones are like melling or comp cams parts. They have a wire retainer. The 'microtrol' version has a snap ring style retainer and are what I'm running right now.
I went through 4 sets of comp lifters and all 4 sets were spongy after break-in. The microtrol have been rock solid so far. Never get any tapping, and comparing the workmanship on them to the last set of comps I pulled, it was night and day. Hard to explain the differences as they're pretty subtle and all has to do with the manufacturing, but it was obvious they were manufactured by someone who cared. No idea if I got some old stock though.
 
Good point on the centerline. Was this cam degreed or just installed by lining up the dots on the timing set?

Cam was degreed. Although it was my first time dong it. I set it at dot dot and then verified the degrees and it came out to 106, like the cam card showed. I know I re did it multiple times to be sure I got the same number.
 
They offer two types, the 'standard' ones are like melling or comp cams parts. They have a wire retainer. The 'microtrol' version has a snap ring style retainer and are what I'm running right now.
I went through 4 sets of comp lifters and all 4 sets were spongy after break-in. The microtrol have been rock solid so far. Never get any tapping, and comparing the workmanship on them to the last set of comps I pulled, it was night and day. Hard to explain the differences as they're pretty subtle and all has to do with the manufacturing, but it was obvious they were manufactured by someone who cared. No idea if I got some old stock though.

Second time I have heard the microtrol lifters. I am not sure which ones I got for the cam, Ill have to look as I bought the cam and lifters separately, because the "kit" was out of stock.

Found them. Lunati 71977PR-16 Lunati Performance Replacement Hydraulic Lifters | Summit Racing
 
Vacuum can depend on many many different variables. Idle speed, cubic inches, idle timing, health of the ring seal, etc etc etc. Don’t put a label on any specific camshaft and say it needs to have “this or that” number to determine the health of your engine. Saying one engine made 11” with that cam and yours makes 8” with it is not a viable comparison.
 
Cam was degreed. Although it was my first time dong it. I set it at dot dot and then verified the degrees and it came out to 106, like the cam card showed. I know I re did it multiple times to be sure I got the same number.

Perfect! Just checking. Trying to cover all the bases.
 
Have we seen or heard a video of the issue?
 
The fact that your valvetrain is adjustable does not rule out my comments in post # 147. Spongy lifters or lifters that do take take up the clearance would produce noise.
 
UPDATE:

I lost the cam, it appears. There is shiny glitter in the oil and in the oil filter after he cut it open. So the motor has to come out and gone through. Super disappointed.
 
UPDATE:

I lost the cam, it appears. There is shiny glitter in the oil and in the oil filter after he cut it open. So the motor has to come out and gone through. Super disappointed.
that sucks , seems it happens often these days , just hope my 340 don't suffer the same fate once i get it in the car , only has dyno pulls and break in so far , but with all the QUALITY parts on the market today who knows ?
You got no miles on the engine , who covers the cost of a rebuild ?
 
that sucks , seems it happens often these days , just hope my 340 don't suffer the same fate once i get it in the car , only has dyno pulls and break in so far , but with all the QUALITY parts on the market today who knows ?
You got no miles on the engine , who covers the cost of a rebuild ?

Yea, I dont know. This is on me as I put it together. I should've just left well enough alone. Lol. I put the 4 speed in and thought I would upgrade the heads and cam. Oh well.

It's just disappointing, that I have had this thing since 2013, rebuilt from the ground up and still haven't been able to drive it for more than a summer due to one issue or another. *Sigh*

I'm getting pushed to put a roller in it and be done with it. I'm gonna get it trailered home and start tearing the motor out soon.
 
Yea, I dont know. This is on me as I put it together. I should've just left well enough alone. Lol. I put the 4 speed in and thought I would upgrade the heads and cam. Oh well.

It's just disappointing, that I have had this thing since 2013, rebuilt from the ground up and still haven't been able to drive it for more than a summer due to one issue or another. *Sigh*

I'm getting pushed to put a roller in it and be done with it. I'm gonna get it trailered home and start tearing the motor out soon.
**** THAT NOISE it ain't on you , it is the **** made i craopostina that is to blame F T or roller crap is crap seen plenty o cheap roller **** crap out as well(noodle bearings) . How is it we put millions of miles on FT cams all those years ? Good luck on the new build
 
That sucks..
Buddy of mine lost a cam in his RB motor last year. Had chunks of lifter come out the drain hole..
 
not good news, but at least you know.....
If you do not want a repeat performance & decide to stick with a FT cam, find some lifters that are 25 yrs or older [ stock or aftermarket ] & have have them re-faced....
 
not good news, but at least you know.....
If you do not want a repeat performance & decide to stick with a FT cam, find some lifters that are 25 yrs or older [ stock or aftermarket ] & have have them re-faced....

I think I'm gonna go roller. As much as I do y want to spend the money, I want to be able to drive and enjoy the car.
 
Yea, I dont know. This is on me as I put it together. I should've just left well enough alone. Lol. I put the 4 speed in and thought I would upgrade the heads and cam. Oh well.

It's just disappointing, that I have had this thing since 2013, rebuilt from the ground up and still haven't been able to drive it for more than a summer due to one issue or another. *Sigh*

I'm getting pushed to put a roller in it and be done with it. I'm gonna get it trailered home and start tearing the motor out soon.
Don’t feel so bad, these things can happen to all of us, you’ll get it right! I love the way you openly share your info - good news and bad.
I’ve just had to remove my trans after thinking that I was just about to finally start my engine after a five year car build, too depressing to share though!
All the best with the rebuild, please keep us posted.
 
new lifters are hit or miss , vacuum seems about right for that cam think my 340 with similar cam had 13 vacuum so you are in the ballpark .
good luck
.484 here in a 340, idles at round 11, I think. If I can remember.... lol. Finally got some steroids to open up my lungs after 6 weeks should not be able to breathe from covid-induced bronchitis. I'll go look tomorrow. Ain't played in too long, between the rain and that
 
Don’t feel so bad, these things can happen to all of us, you’ll get it right! I love the way you openly share your info - good news and bad.
I’ve just had to remove my trans after thinking that I was just about to finally start my engine after a five year car build, too depressing to share though!
All the best with the rebuild, please keep us posted.
Keep your Head up Brother! Man, that had to suck... hope it goes Well, and Swift on the new attack!
 
-
Back
Top