That really sucks Doug. Thats one reason I had K1 do those rods as the guy helping with my build wont use factory rods in a hp build. Next time stay off the 1000 hp fogger system eh?

_________________
it's like a vw, sounds like a million miles an hour but goes really slow. (for now)

What a pitty ... too bad Doc. Not even had the change to enjoy it a little ..

_________________
Martin Zappettini
1974 Dodge Polara RT 318cu.
1965 Valiant III Coronado Slant Six 6-Pack (soon!!)

I don't, nor have I ever understood the obsession with light weight engine internals.

I hear all the it revs faster and such, Yes in neutral maybe but it is not the crank weight or rod weight holding you back at the track. It is the weight of the car. At this point the light weight internals are irrelevant.

I know I am stupid and how can I say such nonsense . I can live with that. I get the same stuff when we built sixpack con rod 440 with six pack pistons. "The rods are too heavy" , Even the great RE likes to say how those pistons are too heavy. Those rods though, according to a engineering bulletin in house Chrysler which I have were almost twice as strong and those pistons were same weight as stock, except they were forgered replacement TRW.
These motors have run for years. Two are still going that I built in the 70s and these are race engines , not street. I doubt they would have made 1/1000ths of HP more if light weight. And to put it all in perspective if you took a hemi rod from a 426 and weighed it against a 440 rod you lightweigt guys would have heart failure. And yet the Hemi crank and 440 crank are the same dimensions and bearings and stroke.

I would use the lighter if two components if both had the same strength. Light weight however speaks to RPM and piston speed in feet per minute. The higher the RPM the lighter the components have to be to survive otherwise the loading gets out of safe range but they also need to be stronger. Not an easy thing to do. If you switch to lighter weight componets, as you begin to exceed the safe limits of Piston speed in feet per minute, you can cheat the blowup monster a bit because the loading is less and it buys you a bit more safety factor. This though, is a very fine line and most engine builders try it once in their life and realize immediately that it is not the be all end all it would seem to be.
Better to build it lightest that is practical rather than lightest that is possible.
Having said all that, a slant 6 (or a 440 for instance) running a 6500 on its best day is not going to give a tinkers darn about weight of the crank or rods or pistons. At 8000 it would be a lot more relavent.

I'll duck now while you all take your best shot but you wont change my mind. An engine that can't survive is far more useless than an engine with 15 grams too much piston weight. Or in plain english you must finish the race to win.
Don

_________________
Don

Bad news, Doug. Sorry about that. That did seem to be a lot of grinding on those rods. What RPM were you turning?

The narrow K1's are now ready, although I bet you're not going to try this combo again really soon.

Lou

_________________
Home of Slant6-powered fun machines since 1988

Thanks for the condolences and comments... yes, it's disappointing that this engine failed so soon.

I knew the risk going into this build and to be honest, I expected some type of failure... why else would I name the thing "Buster"
This is the reason I started with a "junk" almunium block and "revived" it, I did not want to risk trashing a nice one.

As for Don's comments, I agree that strong parts are worth the weight penalty for just about all street and most race applications... you need it to stay together. The Requal engine I build 2 years ago used that mindset and that race engine has about 75 WOT N2O passes on it, best of 12.52 at 106 mph.

Rock-solid performance with reliability was not the focus of the Buster build... the goal was "How light can you get a SL6 combination that will stay together... So far, I know I can get the full engine down under 300 lbs (272.5 lbs for Buster) but as we saw, I missed on the "and stay together" part.

I will need to pull the engine apart and see what really happened. My thinking is that I can add a little more strength to the needed area(s) and get this combo to work.
DD

Thats a bummer Doug. Is this the engine with the Al. head? If so, is the head ok???
That would be a terrible loss.

AZ

I do however salute you as a fellow who has an idea and chases it down. No matter what the actual result I believe you have gained knowledge in this build you would not have come across otherwise. I in particular liked your machining of the upper end of the free standing cylinders.

I wonder if 4.1 Caddilac cylinders could be used in the AL /6 block. They might be too short or maybe not big enough in bore to justfy it but if they would work it is an easy install. They seal on the bottom with a flat thin ring. If the block was bored for a press fit that would be a mott point.
Someone used to sell semi finished Aluminum Rods. maybe it was MT. I think BME will make them too although they would be based on the BBchevy rods. Aluminums are good because they can have more mass for the same weight. They have some approaching 7 inches.
Don

_________________
Don

edit: whoops. was asking if you had any idea what happened.

_________________
72 dart acquired 12/08 /6,holley2b, mopar perf intake, mopar perf header, cam, built motor,904 finally re-installed, 8.75....still needs sorting out.
99 dakota 318 5 speed reg cab picked up 9/09; Trans finally fixed! woohoo!

Echk. The Cattlehack 4.1 has a terrible track record. They don't hold up. I can't imagine it being a good idea to use any parts from them in hopes of building a slant-6 that works and lasts.

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

Be interesting to see what actually broke Doug.

_________________
Official Cookie and Mater Tormentor.

was thinking about head gasket seal issuse.what if you sleeve the o.d. of the cylinder put a 45 degree chamfer on i.d. of sleeve, small chamfer on o.d. of cylinder for weld sink.wall can be reinforced .050-.100 p/s approx.sleeve can be started straight with a couple of thousands clearence most of the way and a lite press about the last 1/8 of sleeve.

--------------------------------------------------------------------------------

Echk. The Cattlehack 4.1 has a terrible track record.
I dont think the sleeve knows what engine it is from. It is readily available and an easy install.It is also a free standing sleeve engine.
I have done some and not had problems with them. Biggest probpem was the idea of a 250 Cu inch full size Caddy. The engine itself other then being too small was OK. All i was looking for was a possible source for sleeves. I have a friend who used them to make a bigger stronger 215 Olds engine. He put the caddy sleeves into the aluminum Olds block with good success. Anyway just an idea .
Don

_________________
Don

The Cadillac 4.1 L has a 3.465" bore. What are the other dimensions on these sleeves?

I dont know but may be able to put my hands on one and find out
Don

_________________
Don

Doug,

You probably already know this, but the K1 7.005" narrow cast crank rods are now on the shelf. I have a set and they look as good as the wide rods.

Lou

_________________
Home of Slant6-powered fun machines since 1988