I have a 1989 Formula with a TPI 350. The Crankshaft broke. What should I do? Also, would a TBI 350 in a truck perform well in my Formula?

 

How do you mean the crankshaft broke?

The 350 L05 TBI engine will work well IF you use your stock TPI heads over the ones that come on it.

 

Yea post some pictures of this broke crankshaft. I'm interested in seeing it.

As for the 350 TBI in the Formula, get rid of the heads and the peanut cam and it will be ok. Basically, by time you get done stripping the less desirable parts off of the 350 TBI, all you will have left is the short block, less the cam. TBI in the stock form is a far cry from a performance based engine.

 

Ep, ya forgot about the cam too (mine was swapped withing 45 minutes of getting it in my driveway). You'd be better off to find a (edit) short block and swapping in your stock heads/cam or better if you're buying one new or rebuilt, but if you can find a cheap junkyard engine with the L05 specs, and you must, do like we suggest and dump the heads and cam for your stock ones, or better.

 

i'd like to see the broken crank too or a little more detailed explanition of the problem.

 

Every motor I've ever either had or seen with a broken crank, was from over-revving.

Most of them seem to break right at the front, somewhere having to do with the #1 rod throw. Torsional vibration is what gets them.

While replacing a crank is cheap and easy in and of itself, whatever abuse the motor has suffered in its life has surely left its mark in over-stressed rod bolts, egged rod big ends, valve train float, cracked or severely scuffed piston skirts, etc. etc. etc. Whoever ran a TPI motor at such a high RPM as to cause this to happen, obviously didn't understand about how a car with an induction system that limits max HP to 4500 RPM never needs to rev beyond that; that is, the car will go the fastest if shifted at somewhere near that RPM, thus making it counterproductive to wind it up excessively. Plus, since cranks don't generally break from one instance of this but rather from a long-term pattern of it, means that most likely this was not just a one-time slip of the foot or something, but rather a repeated, sustained, deliberate mis-use and abuse of the engine.

Sorry to hear that your car has been so pointlessly abused over the long term. Expect to find other evidence of abusive behavior.

The truck short block will work OK, if you put the L98 heads on it. Otherwise it will be even more induction-limited by the L05 heads than it is with the TPI itself. The truck motor will most likely have a flat-tappet cam in it, which will be a pretty weenie one; you might want to consider replacing it with something more appropriate to the application.

I'd recommend replacing the valve springs while you're at it, since those have almost certainly been stressed and overheated to the point of fatigue as well by the over-revving abuse.

 

I'm at my college at the moment and can't take a picture, but the crankshaft broke at the front. This is causing the motor to make a knocking noise. What should I do?

 

The crankshaft is inside the engine so unless you have the oil pan off, I don't see how you can tell it's 'broke'. Do you mean the balancer and pulley 'broke' off or what??. I don't think anyone knows what you mean by 'broke' Can you please clarify that for us? HOW exactly is it 'broke???

 

I took it to a mechanic. He took off the balancer and pulley to recognize this problem. Basically I'm going on his words. It will crank up but sounds like S*it. What are usually normal problems for a broken crankshaft?

 

If you had a broke crankshaft, it more than likely wouldn't run, at least not even in a half-@$$es manner.

I'm going to take a guess and say that there is a loud, dull, metallic clunk/thunk that is coming from the bottom center of the engine. And if that is the knocking noise, you didn't break the crank. You spun a bearing.

87 is correct, the crank is inside the engine, held in place by several main caps. So even if it DID break, thanks to the front main cap and timing chain, it wouldn't be any different really. Take the pan off. I'll bet your crank is in 1 piece.

 

There's clearly a misunderstanding taking place here.
My guess is that it might even be something as minor as the harmonic balancer bolt being stripped or broken off , and you misunderstood that as being a broken crankshaft.
A broken crank is catastrophic failure of the worst kind, and the effect of that would be that your engine ceases to run instantly, accompanied moments earlier by a horrendous clattering sound something like what you might imagine a bucket full of billiard ball sized rocks being dumped down your intake while the engine's running (if they would fit) would sound like.

I'd say take it to someone else for a second opinion. But that might be hazardous, as the engine could self destruct on the way there.