My motor...she's dead.

[HICKL]

Have not dropped the pan yet (which has some new dents and holes) but after removing a head, number one piston has vanished. I found traces of it everywhere from stuck in the intake valve to deposited in the number 7 cylinder. Strangly enough, the rod (a bit twisted) is still on the crank with the wrist pin in tact and seems to operate smoothly on the crank itself. Appears to be a piston failure. Block is also broken thru to the water jacket in that cylinder. I will get it on the stand tomorrow and pull the pan, kind of wondering what happened.

 

Once I get thru crying, I will post for advice on build #2. Times a wastin!

[Ledphoot]

Sounds like possibly detonation or valve to piston interference. How much timing were you running, what compression and what fuel? When you dig out all of the pieces try to reassemle as much as you can and see what king of marks are on the head and piston.. Check the valve spring pressure as well and the lifters for that cylinder. Weak spring and valve foat will slap the valve into a piston as well. Could also have been a cracked piston from assembly, they can hang on quite awhile sometimes depending on how long you've ran the motor and how hard..

[jbk240z]

I'm sorry to hear about the passing of your motor. Look at it this way, it gives you a reason to build a better motor. Good luck!

[grumpyvette]

sounds like DETONATION for sure, and WERE those HYPEREUTECTIC pistons?

THEY have a bad rep for desintegrating if both detonation and impact damage occure,

and detonation tends to break chunks of the ring lands loose, that get crushed between the chamber and piston, forged pistons won,t do that unless the detonation becomes severe/prolonged

[HICKL]

Hey Grumpy, they were Hypereutectics.

 

Here's the story, I had decided that I was tired of the tunnel ram for a while, so I dyno'd it friday, drove home (30 miles) and tore it apart. Bolted a perf RPM on it and was doing the initial tuning. It would begin to make a cladder sound if it idled for very long. I jacked around with everything, got the timing set and then this happened. Is is possible that during the intake swap I could have dropped something into the intake port? I don't think I did but who knows. It would have to have been small enough to get by the valve and big enough to destroy my piston. I took the valves out and didn't see any sign of something beating it's way thru there.

 

Thanks

Jeff

[grumpyvette]

sounds like detonation broke a ring land, it got crunched, the piston tried to compress a chunk of aluminum and shattered, (comon with hypereutectics once detonation occures) now don,t get me wrong hypers work extremely well and hold up fine in a street application, but once the heat levels go up to higher performance levels....

forged are a better choice, they tend to hold together even mangled, which might have kept the rod from beating a hole in the block when it came loose.

[HICKL]

Enough crying over spilt milk. Let's talk new build. Hopefully my heads survived, if so, I am considering building a stroker. I have to keep a reasonable budget in mind so here's my questions. Will these sportsman II do feed a decent stroker? New heads are not in the budget. I have easy access to another "010" block but it is a 2 bolt main. Would it be a bad idea to build a stroker around a 2 bolt main?

 

This is and will continue to be a street car with once or twice a year 1/4 mile runs. Should I build a stroker with the above mentioned parts, (might be able to find a 4 bolt) or just another 350 with better internals than I used last time.

[grumpyvette]

whats your goals (hp) and your rear gearing and transmission? will it be required to run on pump gas?

look I can easilly give you a decent combo, but most guys (get a deal ) and fail to EXACTLY match components then wonder why it won,t run up to expectations OR they want a killer race hp but don,t want to put up with rought idle and low tq at low rpms,ETC. so please state your REAL goals and lets work on meeting them as closely as is practical in your budget.

have you had those heads checked for cracks and flow rated?

BTW a two bolt block, stroker with ARP main studs will work in most street/strip engines, and a stroker IS THE WAY TO GO!!!!

its an ALMOST FREE extra 40-50 hp/tq over a similar 350

[Ledphoot]

Ditto Grumpy. also..David Vizard is a great engine builder and even he says 2 bolt mains are fine for street/weekend warriors. 4 bolt is for high and prolonged rpm. Quality machine work and balancing is the key to durability. 383 stroker is an easy, proven and affordable build. I also like the 406 but cooling is crucial with the 400 blocks siamese bores.

[HICKL]

whats your goals (hp) and your rear gearing and transmission? will it be required to run on pump gas?

look I can easilly give you a decent combo, but most guys (get a deal ) and fail to EXACTLY match components then wonder why it won,t run up to expectations OR they want a killer race hp but don,t want to put up with rought idle and low tq at low rpms,ETC. so please state your REAL goals and lets work on meeting them as closely as is practical in your budget.

have you had those heads checked for cracks and flow rated?

BTW a two bolt block, stroker with ARP main studs will work in most street/strip engines, and a stroker IS THE WAY TO GO!!!!

its an ALMOST FREE extra 40-50 hp/tq over a similar 350

 

I would like to get around 400 hp as a goal. I'm 99% sure my rear end is a 3.54, I am running a G-force built T5 that should handle more power than this. I want to run on super unleaded pump gas. Heads have been dropped off this morning for crack test. I want it to be strong but driveable. I'm looking for that happy medium. It is a street car that I drive to work once a week or so and spend time in stop and go traffic!

[Ledphoot]

Prime candidate for a SCAT 383 kit forged !. 10008 Crane cam. Edelbrock RPM airgap(good all around street) intake or a Victor JR (more topend less bottom torque) keep it under 10.0-1 compression and keep it cool and premium with modest timing will be fine. A little more timing and race gas at the track. Add a shot of No2 and you'll have a fun run! if you dont mind a little more radical cam thats fine too.. always opt for 1.6 roller rockers or go to a Crane 10082. I'm assuming your not a roller motor.

Tunnel rams are cool looking, put it takes mucho cam to make them work and they're not designed for street.. But I still like to run em for looks!!

[dr_hunt]

I've made 630HP NA on alky with the sportsman II heads, pretty good choice IMO for what you have. Should work well on a stroker 383. They don't flow alot over .550 lift, so IMO keep the lift reasonable.

[BillZ260]

just fyi if you need a set of KB hypers I have a set of 12cc dish, but they are std bore Make you a deal.

[grumpyvette]

http://www.chevytalk.org/threads/showflat.php?Cat=0&Number=1527608&an=0&page=0#Post1527608

 

heres some places to look, but remember to ask ALOT of questions CHEAP usually means LESS QUALITY

 

http://www.scatcrankshafts.com/PDFs/Crank06.pdf

 

http://shop.enginekits.com/osb/itemdetails.cfm?ID=2117

 

https://www.competitionproducts.com/prodinfo.asp?number=SS383F

 

http://store.summitracing.com/partdetail.asp?part=ESP%2DB12011030&N=700+115&autoview=sku

 

http://store.summitracing.com/partdetail.asp?part=ESP%2DB12010030&N=700+115&autoview=sku

 

http://www.jegs.com/webapp/wcs/stores/servlet/category2_10001_10002_22553_-1

[HICKL]

Ok guys, I should really make up some elaborate story about a 150 shot of NOS killing my motor or something like that but whats the point of being stupid if you can't laugh at yourself. Notice the bent up 1/4 inch bolt in the pile of rubble. Yep, I must have dropped a bolt while removing the tunnel ram. I bet I don't do that again.

 

http://album.hybridz.org/showphoto.php?photo=12309&cat=704

 

The real bummer is that after 2 or so years of abuse all the critical components in of my motor where in great shape. Barely broke in I would say.

 

Anybody lookin for a deal on seven pistons? I'll throw in 7 rods!!

 

Ever heard that song..."If your gonna be dumb, you gotta be tough"

[v80z]

Ah Dude

 

I am sorry for your loss. On to bigger and better.

[dr_hunt]

Love the avatar v80z!

 

I say go cubes, you need more inches!

[DavyZ]

Yep, I must have dropped a bolt while removing the tunnel ram. I bet I don't do that again.

 

 

 

It takes a real man to admit that in a public forum!!

 

I will, however, not extend any grace and will enjoy laughing at your expense! j/k

 

I think a 400 hp 383 SBC will be the hot ticket for your car. I do hope you can salvage most everything else on your present motor, which was pretty cool to begin with. Maybe Santa will deliver you something cool, eh?

 

Davy

[Ledphoot]

WELL>>>> I'd like to say I've never done that but Santa Claus is watching me...Only cost me a somewhat rare 421 super duty pontiac motor with a sweet tri power set up.. I've had a motor suck a grease rag outta my hand and bend some valves too... As the old proverb says.. "Too be old and wise you must first be young and stupid"..or at least clumsy..LOL

Gee those stainless intake bolts are tough aren't they??

[Forces]

It takes a real man to admit that in a public forum!!

 

I will, however, not extend any grace and will enjoy laughing at your expense! j/k

 

I think a 400 hp 383 SBC will be the hot ticket for your car. I do hope you can salvage most everything else on your present motor, which was pretty cool to begin with. Maybe Santa will deliver you something cool, eh?

 

Davy

 

I've got a buddy, and that buddy ISN'T ME, that had a ratcheting box end explode and part of it got sucked down into the intake valve on cylindar 8. destroyed the valve, wrecked the piston....it wasn't pretty. I think It's still under the knife from that mess. The strange thing is that the rest of the wrench is nowhere to be found..... sounds like a sequel might be in the making.