Grinding, " diesel " noise under valve covers

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The BOSS 429 Fords were the same. Pistons sounded like they were swappin holes when they cranked up cold. So did the LS6 454 Chevelles and Corvettes. Any loose HP engine with lots of compression is gonna rattle every bearing and piston in it. It's just the nature of the beast. That's how they make power.
 
Ironracer said:
Whoops... so just put my ear down to the pipes? It definitely isn't where I can hear it standing there. Or do I put my head on the pipes, while cold? No
.. wait,, that vibration would be all I felt... crap.
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You're not gonna hear it through the pipes. You know why? Because of the.......wait for it........EXPLOSIONS in the cylinders. Hear it through the pipes. Now I know he's crazy.
 
Thank You Rob! I'm already losing sleep over this... I think you have the right answer. Move Forward, I know that sound has been there a minute. And she's been flogged! Lol! I had a guy, a Thunder Bay, a Harley shop.. Ray, the owner ran drag bikes, he was cool. I popped a vavle spring racing, stopped by to see what they had, Ray was not there, but his Ironhead "guy" told me to flush the motor with a garden hose... to clean it .. they have burned a few people I know. . But to offer bad advice, when I ain't asked? Heck, I just wanted to see if they had a valve spring.. lol
 
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Another thing, I bought the short block, assembled, for a grand, in 08. Only thing that I didn't build. Other than having the heads checked ( I wrecked 2 rental compressors, ended up buyn a bad *** lever one,, to put my own springs on,, heads were off a running motor, I was told, but wanted em looked at) Trans looked at. The dude I got it from was an Army Aircraft mech, then had his own shop..he was a Mopar racer. Had about 5 340s... and a badass low 10 sec dart.. motor came w/ a soild cam and a spare... I called him, and told him I went to a hydraulic. Drill Sargent mode. Kinda yelled at me..
" YOU DID WHAT TO MY MOTOR!!!! ITS A SMALL BLOCK DAMMIT!" so the clearance thing adds up good..... makes sense
 
Ironracer said:
Another thing, I bought the short block, assembled, for a grand, in 08. Only thing that I didn't build. Other than having the heads checked, and Trans looked at. The dude I got it from was an Army Aircraft mech, then had his own shop..he was a Mopar racer. Had about 5 340s... and a badass low 10 sec dart.. motor came w/ a soild cam and a spare... I called him, and told him I went to a hydraulic. Drill Sargent mode. Kinda yelled at me..
" YOU DID WHAT TO MY MOTOR!!!! ITS A SMALL BLOCK DAMMIT!" so the clearance thing adds up good..... makes sense
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May have floating pins in it. Do you still have his contact info?
 
Listen to this. Sound familiar?

 
RustyRatRod said:
May have floating pins in it. Do you still have his contact info?
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I know the old TRWs I have laying round for this ol.440 I've had in the shed for 10 years or so have floating pins.... I pressed the old stock pistons off the factory " 6 Pak type " rods. And used c clips on the new ones, but still had to lightly press em. 74 HP box truck block. Scored used. 030 11.5 :1 w it. During the Obemmer years, a Bro pretty much drove em to my house w/ some ported heads and a TM7 intake, w/ a manual vb 727... needed Christmas $. I really couldn't say no......I didn't want em, really, but he needed the cash... I didn't even know he was coming. And happened to have work that holiday.. Anyway, not sure if all the old TrW forged units were clipped
 
Ironracer said:
I know the old TRWs I have laying round for this ol.440 I've had in the shed for 10 years or so have floating pins.... I pressed the old stock pistons off the factory " 6 Pak type " rods. And used c clips on the new ones, but still had to lightly press em. 74 HP box truck block. Scored used. 030 11.5 :1 w it. During the Obemmer years, a Bro pretty much drove em to my house w/ some ported heads and a TM7 intake, w/ a manual vb 727... needed Christmas $. I really couldn't say no......I didn't want em, really, but he needed the cash... I didn't even know he was coming. And happened to have work that holiday.. Anyway, not sure if all the old TrW forged units were clipped
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Forged pistons are normally louder especially cold, because they have to have more clearance.
 
Ironracer said:
Yessir, Understood. They expand at a different rate, I believe, or a different amount, than cast or hypers.
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They're called cam ground. When cold they're elliptical. They are designed so when they heat up they become round. So in order for them to work, they have to have the proper clearance, which is a good bit more than a cast or a hyper, hence the extra noise. A lot of machinists give them some extra clearance as a cushion and they make even more noise. As long as they're forged, it won't hurt a thing. I THINK that's what you have going on. Just cool out on something else for a while. When you're able to actually drive it for a while, then we'll know for sure.
 
Man, I REALLY appreciate your time and knowledge... and I have a clear Plan now. Get her back Rolling!!!! Evaluate, and go from there. I'm still going to cut the filter.. that's new VR1 20-50 well , a year old , but no real miles to speak of. But alot of driveway idle time, and no really long trips... but some great passes by the cows...it looks filthy..
 
RRR is on it about piston slap. Whether that's what your issue is depends on the build and the clearances of course, and how much it quiets (if at all) when hot, but if it helps any
mine is a 600-neighborhood forged-piston RB stroker, set up a little on the 'loose' side....and it has some piston slap. It makes a noise very similar to yours when it's cold....and it takes some driving and heat soak to really get the engine hot and tame it (cooling system almost works too well in colder air!)...

I had this clip of mine at a hot idle, you can barely hear that lower-frequency tap with the right ears but it's quite a bit more noticeable when cold---



And what the heck some tailpipe idle too
 
beanhead said:
RRR is on it about piston slap. Whether that's what your issue is depends on the build and the clearances of course, and how much it quiets (if at all) when hot, but if it helps any
mine is a 600-neighborhood forged-piston RB stroker, set up a little on the 'loose' side....and it has some piston slap. It makes a noise very similar to yours when it's cold....and it takes some driving and heat soak to really get the engine hot and tame it (cooling system almost works too well in colder air!)...

I had this clip of mine at a hot idle, you can barely hear that lower-frequency tap with the right ears but it's quite a bit more noticeable when cold---



And what the heck some tailpipe idle too
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Hey, Man, Thank You for taking the time to do that! Much appreciated Sir! And that Badass, Hungry Mopar is sounding MEAN!
 
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That 427 sound like my buddies cammed 351C with about the same length exhaust. 24" Glasspack "truck mufflers" with a 3 bolt flange right off the 2" header collector in a 72 Mustang. Still sounds like a rotary noise, like a pump cavitating to me but if it don't bother you, run it. Throw some cardboard in front of the rad to heat it up.
 
pishta said:
That 427 sound like my buddies cammed 351C with about the same length exhaust. 24" Glasspack "truck mufflers" with a 3 bolt flange right off the 2" header collector in a 72 Mustang. Still sounds like a rotary noise, like a pump cavitating to me but if it don't bother you, run it. Throw some cardboard in front of the rad to heat it up.
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Yikes! Like oil Pump Cavitation? Arrrghhh! Nooooo!
 
So I'm gonna rip out the front area tile in a Hungry Howiez my Friend owns. He's also Always been a Mopar guy, and has had / built some bad rides. He still has a 71 Cuda 340, 4spd car. Had a 426 wedge in it, w/ a cage... he took it back to stock. Anyhow, gonna be doing 11 pm till when ever in the am at his shop. I should be able to get him by. I did start getting her ready to roll yesterday evening. Got a different dizzy in, timed er out. Ride height looks good, wanna double check both sides are the same before I lock down and torque stuff up. It's hard to get a super accurate # w/ a tape... I see the FSM show a wood ( looks like a folder) . I wish I knew where to get a slide rule...
 
Just for grins, how about pulling the distributor and pump drive once more and priming the pump with a drill? If the pump is loud, youll hear it. Or you can do it at your friends house. Just to isolate a pump noise. Once the timing cover is off, you should get alot more info.....
 
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