Yes. That’s a small move but going down .002 on the MAB will delay the booster making it leaner (because it’s still on the T slots and it’s still getting some fuel from the idle circuit and not on the booster) but it will make it richer at WOT.
Fine Tuning a 360 Magnum with a Brawler "Double Pumper"
- Thread starter jmanhoff
- Start date
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Yes. That’s a small move but going down .002 on the MAB will delay the booster making it leaner (because it’s still on the T slots and it’s still getting some fuel from the idle circuit and not on the booster) but it will make it richer at WOT.
So I can go smaller on the MABs to a point to fine tune my cruise after getting my transition circuit ironed out, and use PVCRs to fine tune WOT? Or is it more complicated because of the secondary circuit?
Well guys. Update, and not a good one. I royally screwed up my engine. I replaced my lifters with the Hughes 5007 lifters, ticking went away, but what I didn’t notice is that the intake manifold gasket on the driver bank slipped off slightly so it did not seal the rear coolant jacket, and it dumped coolant into my oil.
Engine ran fine yesterday for 15 minutes before I realized there was coolant in the oil (almost 2 gallons). Drained the oil, pushed it back into the garage and let it sit overnight while I waited for a new intake gasket. (I was hoping I got lucky as the engine was still running at the time).
New gasket on, added oil, started it up, ran for 5 seconds, died while making an awful screeching noise, and would not turn over. Plugs out, belt off, breaker bar on crank doesn’t turn engine over, and the starter does but it sounds like an old tractor with a dead battery.
Guess I have to pull the motor again.
Engine ran fine yesterday for 15 minutes before I realized there was coolant in the oil (almost 2 gallons). Drained the oil, pushed it back into the garage and let it sit overnight while I waited for a new intake gasket. (I was hoping I got lucky as the engine was still running at the time).
New gasket on, added oil, started it up, ran for 5 seconds, died while making an awful screeching noise, and would not turn over. Plugs out, belt off, breaker bar on crank doesn’t turn engine over, and the starter does but it sounds like an old tractor with a dead battery.
Guess I have to pull the motor again.
None that I know of but I didn’t knock on wood before I started it up after the reseal, probably what made it lock up
Yeah well, hey, thinking positively, I can get a new OEM oil pan to ideally stop my seemingly unfixable front pan leak with my Dorman pan, do some wire management and frame cleaning on the nose of the frame with the engine out, and some other misc things I’ve wanted to do.
For those still following this thread lol, I am in the process of reassembling the engine. Rod number 6 was the one that spun, luckily it did not wipe out the crank it only took out the bearing.
I got the block cleaned, deglazed, and the crank polished. Machine shop measured all 8 rods and found that rod 6 was .0015” smaller than the other 7 (it was also a reman rod). Got that fixed, I’m happy with the new clearances, and I’m getting ready to put this engine back into the truck now.
I got a new cam as well. Switched from the comp 20-745-9 XE to the Hughes SER0814ALN-14. Shorter duration but higher lift, supposedly will help with low end torque and efficiency. I measured my pushrods and with the comp I measured 6.76” zero lash, but with the Hughes I’m measuring 6.805”. Would this make sense?
I got the block cleaned, deglazed, and the crank polished. Machine shop measured all 8 rods and found that rod 6 was .0015” smaller than the other 7 (it was also a reman rod). Got that fixed, I’m happy with the new clearances, and I’m getting ready to put this engine back into the truck now.
I got a new cam as well. Switched from the comp 20-745-9 XE to the Hughes SER0814ALN-14. Shorter duration but higher lift, supposedly will help with low end torque and efficiency. I measured my pushrods and with the comp I measured 6.76” zero lash, but with the Hughes I’m measuring 6.805”. Would this make sense?
gzig5
Well-Known Member
Caught it in the nick of time.
I wouldn't expect two different cams from two different companies to have the same zero lash length on the pushrod. The difference could be the difference in lift but not familiar with those two cams and too lazy to look them up. Lobe geometry is not written in stone and the lift number is related to the base circle diameter, all of which would influence the push rod length, if I'm understanding your question correctly.
I wouldn't expect two different cams from two different companies to have the same zero lash length on the pushrod. The difference could be the difference in lift but not familiar with those two cams and too lazy to look them up. Lobe geometry is not written in stone and the lift number is related to the base circle diameter, all of which would influence the push rod length, if I'm understanding your question correctly.
Allegedly both cams are designed to have the same magnum engine base circle, but I’m sure the Hughes is a reground cam so the base circle is smaller (hence the zero lash is a larger measurement). I thought about this this morning, guess my brain was too far gone last night to put those two things together lol
Got the engine all put back together and she runs. I did the break in for the cam even though you really don’t need to with a hydraulic roller, but what harm could it do.
75 psi oil pressure at 2200rpm consistently, no weird noises, and no forbidden glitter in the oil after the first drain. Surprisingly high idle vacuum, 23 inches or so at 700rpm, seems a bit high to me.
I have not moved the truck yet, I ran it for about 20 min for the cam, changed the oil, and let it idle to do a walk around. There is still quite a bit of valve clatter, it’s symmetrical side to side so it doesn’t sound like an exhaust leak and it’s rhythmic it’s not random. I do have the Hughes 5007 lifters which I hear are often louder on a fresh build and will quiet down over time, and will be louder than stock style. They want a bit more preload than stock, I measured 6.81” zero lash and put in 6.9” pushrods, which is in the range they recommend for iron block iron head magnums.
This new cam idles very cleanly too. There is a bit of a lope, but it’s still very tame. I’ll post a video here. And ignore the belt squeal in the background lol, belt got soaked in coolant and sounds like a dying pig.
75 psi oil pressure at 2200rpm consistently, no weird noises, and no forbidden glitter in the oil after the first drain. Surprisingly high idle vacuum, 23 inches or so at 700rpm, seems a bit high to me.
I have not moved the truck yet, I ran it for about 20 min for the cam, changed the oil, and let it idle to do a walk around. There is still quite a bit of valve clatter, it’s symmetrical side to side so it doesn’t sound like an exhaust leak and it’s rhythmic it’s not random. I do have the Hughes 5007 lifters which I hear are often louder on a fresh build and will quiet down over time, and will be louder than stock style. They want a bit more preload than stock, I measured 6.81” zero lash and put in 6.9” pushrods, which is in the range they recommend for iron block iron head magnums.
This new cam idles very cleanly too. There is a bit of a lope, but it’s still very tame. I’ll post a video here. And ignore the belt squeal in the background lol, belt got soaked in coolant and sounds like a dying pig.
Wow, that's great vacuum! Learned a lot through the oops and this build should be a nice one for you! My magnum 360 stroker was also a little noisy but no problems found and ran great!
I think it’s just noisy empty lifters for time being
Yes I verified that on every one
It doesn’t go away with temperature or rpm
TT5.9mag
Two atmospheres are better than one
I guess I should have said “can” go away with temperature. Listen to mine when I first put it back together. Sounds exactly the same as yours and I am positive mine was an exhaust leak because I already fixed it.
PRH
Well-Known Member
I guess sound is in the ear of the listener……..
“To me”, the noises in the two videos don’t sound alike at all.
The first one sounds like valvetrain noise, the second one is an exhaust leak.
That’s how I hear it.
“To me”, the noises in the two videos don’t sound alike at all.
The first one sounds like valvetrain noise, the second one is an exhaust leak.
That’s how I hear it.
TT5.9mag
Two atmospheres are better than one
I’m on a phone so maybe the speaker isn’t great but I watched and listened again. I guess I can hear some clatter. I’ll forgo my previous opinion and say there could be some valvetrain noise going on.
I’m about to go rule out exhaust leak most likely, my oil filter relocation hose decided it wanted to be an oil sprinkler and because I would like to maintain my sanity I’m going to pull the header off to get easier access to the ports. I’ll put some sealer on the flange for the header to downpipe and double check my manifold bolts as well
so I think I ruled out exhaust leak, I retightened all the bolts after I took the manifold off and it still sounds the exact same. I guess next step is to remeasure the pushrods? I thought you’re supposed to measure zero lash with no pump up but it sounds like a broken sewing machine so I feel like every lifter is clicking
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