Just my luck...

[34blazer]

Lower your rpm a bit when it goes together next time. It looks like the bearing got pinched by the big end of the rod egging out. Clevite sells high rpm bearings that are thinner towards the parting line to avoid this, but I don't know if they're available for our engines. You'll need to either replace that rod or recondition it. What kind of oil are you running?

that would be the clevite 77 P bearing i think. running a tiny bit looser on the big end clearance and a HV oil pump should help keep oil on it at high r's.

[gectek]

i dont think volume is what is needed, it would just be extra pressure...shim the spring

[ForcedFirebird]

that would be the clevite 77 P bearing i think. running a tiny bit looser on the big end clearance and a HV oil pump should help keep oil on it at high r's.

Yep. That's what I put in the hybrid

[Superdave]

ok.. at which side of the crank does the oil enter? at the rear main cap?

if so then that could explain a shortage of oil to the #1 rod.

I hate to say what the current plan is, but i think it might last a little longer with a new rod bearing in the current rod.. just long enough to beat the hell out of it on the track and either finish it off or break 12's... or both.

the crank needs to be re-ground, so maybe if/when it gets rebuilt i'll just offset grind it .25" and shoot for 3.8L with a set of 305 SBC pistons (.030" overbore).

Either way, my 7 month prego wife put her foot down and basically my days of throwing money at the car are done for now. Time to focus on the family.. lol

[johnnymossville]

Damn Dave, I am sorry to see this happen. So you have a few more changes in store, eh?

[ForcedFirebird]

Either way, my 7 month prego wife put her foot down and basically my days of throwing money at the car are done for now. Time to focus on the family.. lol

Yep, have to side with the wife After having 4 kids, i learned many moons ago - don't piss off the prego wife, you WILL pay!

[1988GTU]

Thank god I dont have to put up with a wife. I would probably have gotten a divorce with my mod first car.

[34blazer]

ok.. at which side of the crank does the oil enter? at the rear main cap?

if so then that could explain a shortage of oil to the #1 rod.

I hate to say what the current plan is, but i think it might last a little longer with a new rod bearing in the current rod.. just long enough to beat the hell out of it on the track and either finish it off or break 12's... or both.

the crank needs to be re-ground, so maybe if/when it gets rebuilt i'll just offset grind it .25" and shoot for 3.8L with a set of 305 SBC pistons (.030" overbore).

Either way, my 7 month prego wife put her foot down and basically my days of throwing money at the car are done for now. Time to focus on the family.. lol

theres plenty of things you could do without spending $$$ on the engine to make it more durable for high revs. like you could blueprint the oiling system and radius all turns in the oil passages and stuff like that. when you have the crank offset ground just be careful of how far over the oil passage will end up once its done. you could also polish the rods and all the oil drainback surfaces for more effiecient drainback. since the oiling system is priority main feed, id assume that the #1 rod bearing is the last in the circuit. trace the oil passage all the way back and see if you can find some possible flaws like sharp corners and such. the front main bearing could be another possible canidate for spinning the bearing, like on the ls1 v8's. just a few ideas to keep your project moving in a forward direction. good luck with the fam

[Superdave]

well, it runs again.

I measured the crank and rod end, everything was still good. cleaned up the surface of the journal with some 1K grit sandpaper and cleaned everything up good. Installed the new bearing with plenty of assembly lube.

i cleaned out the pan of course and slapped on a new oil filter and some Penzoil 5W30. it took a few tries to get it to build up oil pressure but once it did she ran great. no knock yet...

I plan on driving it to work a few times this week. I figure that if i don't abuse it, everything should hold together and it might be OK for the track on the 7th.

Wish me luck

[IsaacHayes]

Good luck man, don't forget to change the oil soon again. Hope that was the ONLY bearing with damage. Did you look at any other of them?

[Joseph Upson]

well, it runs again.

I measured the crank and rod end, everything was still good. cleaned up the surface of the journal with some 1K grit sandpaper and cleaned everything up good. Installed the new bearing with plenty of assembly lube.

i cleaned out the pan of course and slapped on a new oil filter and some Penzoil 5W30. it took a few tries to get it to build up oil pressure but once it did she ran great. no knock yet...

I plan on driving it to work a few times this week. I figure that if i don't abuse it, everything should hold together and it might be OK for the track on the 7th.

Wish me luck

Use the recommended 5w30 for the engine it'll pump through a little better than 10w30, and plastigage all replacement bearings to be sure of your tolerances.

I believe ForcedFirebird may be right about potential detonation being behind it or possibly higher than safe cylinder pressures at WOT and 26deg timing. You shouldn't have to do anything special to these engines outside of tightening up the valve train for 7k, they already have a factory fuel cutoff off of 6400rpm. Check your clearances, I made plastigaging bearing tolerances a habit on fresh rebuilds.

Putting an engine together is one of the most rewarding parts of a build for me because I get to try and make everything perfect.

The larger crank pin diameter is actually a disadvantage to high rpm because of the increased speed of the pin rotation surface relative to the bearing compared to a smaller journal and bearing.

[ForcedFirebird]

Use the recommended 5w30 for the engine it'll pump through a little better than 10w30, and plastigage all replacement bearings to be sure of your tolerances.

I thought the first number is the cold flow of oil?

Here's an excerpt:

"The API/SAE designation for multi-grade oils includes two grade numbers; for example, 10W-30 designates a common multi-grade oil. The first number associated with the W is not rated at any single temperature. The "10W" means that this oil can be pumped by your engine as cold as a single-grade 10 weight oil can be pumped. "5W" can be pumped at a lower temperature than "10W". The second number, 30, means that the viscosity of this multi-grade oil at 100C (212F) operating temperature corresponds to the viscosity of a single-grade 30 oil at same temperature. The governing SAE standard is called SAE J300. The motor oil grade and viscosity to be used in a given vehicle is specified by the manufacturer of the vehicle"

[Joseph Upson]

I thought the first number is the cold flow of oil?

It is that's why I was careful to say "a little better" since the greatest amount of engine wear occurs on start up, and some of us don't wait for operating temps to show up before the pedal goes to the floor. I recall being told by a friend who was pretty sure about it that during a test it was proven that engine oil on a cold start takes as much as 30 seconds to fully pump through an engine.

[kflo 93 gt]

guess i'll have to sell a few more OBD1 3400 swap chips to finance it... lol

Heh, I'm ready for one of those myself.

[asylummotorsports]

I have been hearing more and more lately of guys going to 0W30 on these engines to avoid the slow oil pressure build up.

Any thoughts on this?

And hey Dave. My buddy has a 3400 auto '89 Cavy and may be looking for a chip.

How much and what other info do you need?

asylummotorsports@yahoo.ca