Discussion in 'Mopar Performance Issues' started by IQ52, Feb 3, 2018.
So like the stupid thing just shuts itself off on the dyno?
Nice crack! Crack kills!
Ouch...... that hurts
Cracked block ? Or Shrapnel ?
I see both. Hydroloc??
AND where do you suppose that sneaky little exhaust valve head went to?
Shoulda bought the extended warranty I guess. LOL bummer
I'd bet it went over to the pistons house and they both went to visit Mr. oil pan. That sucks man. Do you suppose all those chunks in the valley came out through that crack? Looks like it.
Chev Orange. Does it every time!
The valve head didn't make it all the way to Mr. oil pan like the piston. Those chunks? They did come through the crack. Before the head was pulled you could see the cam and lifters through the exhaust port. This is sorta what happens if you put big valves in a 915 head, put them on a 361 block, and don't check carefully enough to see if the valves are going to hit the cylinder walls. There were divots at the tops of the deck of every bore where the valves were hitting. I'm trying to remember correctly but it seems like it was still making well over 500 HP when it let go.
The valve head? They found it down in that hole into the water jacket. There wasn't any cylinder wall remaining on the cam valley side of the engine.
It'll buff out! JB weld to the rescue!!! Damn...bummer.
Yeow, that sucks. I hate to ask because I don't want to come across like I never screw up but how did it not occur to you that the valves might hit?
Sah good question! It's kinda like this, I didn't build that engine. We were over fiddle-farting with our engine......... ..............and we hear a WHUMP over from Comp Cam's dyno room. I took those pictures as they tore the engine down. With ours, the only problem we had was they forgot to turn the water into the engine before they fired it. I was looking at the dyno control panel thinking something is wrong, when the engine made some weird noises and the operator shut it down. Eight exhaust valves stuck to the bronze guides and the guides were moving up and down in the 906 heads with the valves. My boys on the left and their cousin on the right in Comp's dyno room. After some repairs it made 730 HP.
Looks like a clear case of "Unscheduled Engine Disassembly" ! Yep, I'll bet that's what it is.
Interesting on the h.p. Whats the engine got in it? would like to compare it to mine. Thinking 723 here. Really sucks on the small block !!
Interesting! My first Mopar had a 361 motor in it. I did everything to it that most people did to their 383s in those days (484 purple cam, Edelbrock DP4B intake, Carter AVS from a 440, windage tray, headers, open element air filter, Accel dual point distributor) and it really woke up. My Mopar buddies told me about the potential valve clearance issues if I went to the 915 or 906 heads and tried to run big valves. I ended up rebuilding the original heads with the same size valves.
A little JB Weld will fix you right up.
451 or 470?
Aside from what you see on the outside? Lesse, 56% leakdown with 15 bent valves. Cranking over it would spit back through the carburetor and we couldn't throw enough ignition advance in it to keep the exhaust pipes from glowing red. Nothing much else, 93 octane Sunoco, 11.9:1, our ported 906 heads, Erson solid roller around 278/280 @ .050 and about .800' lift or 280/288 and .780" (probably the later, hard to remember for sure, it was 2011 and I had both cams in my possession), Harland Sharp rockers, Ford blue paint. It made 748 HP at home on 91 octane, with so much blowby it pegged the meter. We changed the ring pack and were breaking the engine in on Comps dyno when the valve guides seized. Two votes for JB weld I see.
The 451 made 723 on Comp's dyno and 787 a few weeks later. We felt like this 500 could make close to 800 before it got toasted. The short block still sets in an AREngineering engine dolly beneath the shops electrical fuse panel. One just never knows, does one?
We all learn from what you do or see...
I thought you'd given up the engine building gig?
Separate names with a comma.