Blowthrough build repeat.
- Thread starter WarWagon
- Start date
WarWagon
Caustic Cacophony
Teardown finished and I glad I bought the new slugs.
Started on cylinder 2 and it's back! Pic1 The moly missing on the top ring that was really the only one like that.
Cylinder 3 was good.
Cylinder 4 was really bad and main problem now pic2. Melted in/under under the top ring through the 2nd ring land and cracked it too.
Cylinder 5 was second worst pic3&4 cracked piston clear to the pin and the top ring is spinning and has no gap like welded together.
Cylinder 6 was good.
Started on cylinder 2 and it's back! Pic1 The moly missing on the top ring that was really the only one like that.
Cylinder 3 was good.
Cylinder 4 was really bad and main problem now pic2. Melted in/under under the top ring through the 2nd ring land and cracked it too.
Cylinder 5 was second worst pic3&4 cracked piston clear to the pin and the top ring is spinning and has no gap like welded together.
Cylinder 6 was good.
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WarWagon
Caustic Cacophony
New pistons and rings in my possession I need to get the rods swapped this weekend. I definitely will be double checking what the ring gap is on the new rings. I might of had it too tight the first time but I also know it got very hot in there so an extra 2 or 3 thousands might happen.
All this from my fuel choice and not paying attention before I made a hit.
All this from my fuel choice and not paying attention before I made a hit.
WarWagon
Caustic Cacophony
I hung the rods on the new pistons and I'll check or redo two of them tonight I'm not happy with pin fitment.
I checked the top ring gap out of the box @ .020 and barely a .021 gauge goes in the gap if I push it. That's what gap I left them at last year when I put this together, now I think I should bump it up to .023
I plan on running a lot of boost on 93/alky again.
I checked the top ring gap out of the box @ .020 and barely a .021 gauge goes in the gap if I push it. That's what gap I left them at last year when I put this together, now I think I should bump it up to .023
I plan on running a lot of boost on 93/alky again.
WarWagon
Caustic Cacophony
Much learned this week and too bad I didn't learn it in 2021. Searching here and the web I found the info, I have been definitely using the wrong ring gaps for what I'm doing. I have to run a larger gap on the 2nd ring vs the top .0024-.0025 for the top and .0026-.0027 for the 2nd.
Houseofspeed posted this similar info in a different thread & I thank this site and a Speedpro instruction manual I read for getting smarter.
Houseofspeed posted this similar info in a different thread & I thank this site and a Speedpro instruction manual I read for getting smarter.
I hate when stuff like that happens, I did the same on a dirt track engine I was building a few months ago, only caught it last minute, thankfully they were floating pins.
WarWagon
Caustic Cacophony
Heads/gaskets went on yesterday and that went well, The longest process for head gasket install but worth it. My Cometic aramid oil pan gasket didn't last past one engine build this time. The first one I was able to reuse four times now I have the dumb blue felpro rubber gasket on. After a torque check of the heads studs tonight I'll finish this top end up so I can stay on my schedule with getting this running this week.
I don't think it matters but I am going to use a steel intake gasket this time, part number says it's for an aluminum intake manifold. I have been using the felpro steel/fiber since the beginning and reused several of them.
I don't think it matters but I am going to use a steel intake gasket this time, part number says it's for an aluminum intake manifold. I have been using the felpro steel/fiber since the beginning and reused several of them.
WarWagon
Caustic Cacophony
Engine is great now, I had to lean out a spot in the fuel table that was very rich from last years fuel line/routing upgrade. Wouldn't think a change in plumbing would cause the tune to need touched up, still learning everyday.
Unfortunately I have to pull the brand new fresh trans out and take back to Extreme automatics, no 2nd gear lost it on my first hit this year with the broken pistons on the street but it was hard to verify with the engine hurt.
Unfortunately I have to pull the brand new fresh trans out and take back to Extreme automatics, no 2nd gear lost it on my first hit this year with the broken pistons on the street but it was hard to verify with the engine hurt.
WarWagon
Caustic Cacophony
This is the longest time span that this machine has sat unbroken and undriven. I got a Dragy and some $$ to go tracks and the streets are always open. Every other day the roads are wet or storms non stop. I'll need to swap this in an AWD or 4wd chassis to use it soon.
There's a small 1/8mi track named Freebird in OH I'm going to start going to
There's a small 1/8mi track named Freebird in OH I'm going to start going to
