so you wiped some cam lobes, ouch. There would likely be "sparkle" in your oil from the metal that was on the lobes and lifter rollers

while some cam cores can be junk or a faulty lifter wipes a lobe..... more common cause is debris in engine or over lashed valve. Attention to the later will keep the new rebuild in good order

At least you caught this before the motor completely blew. I assume you are doing a complete tear down as bearings could likely be scuffed from metal debris in motor

 

Apologies for the long post. I'm guessing over lashed valves. Doing a complete tear down. New cam, push rods, lifters, bearings, and rings. Block, crank and pistons look to be ok but took them to my machine shop just to be sure.

A friend recommended I install a higher stall RPM converter which I want to do now since the engine is pulled. I'm a little confused on that though. Based on the number stamped on the engine side of the converter (20404) I believed I've identified the existing converter as a B&M Torx Master 2400 with a stall speed of 2300 to 2500 RPM. Not sure if there is another way of identifying the current torque converter. Specs I've found on the internet for the B&M 2400 are bolt circle diameter 10.75 inches and a diameter of 10 inches, however the 20404 converter in my car is 9.25 inch bolt hole diameter and 12.50 overall diameter. Based on my buddies explanation and his experience I feel confident he is right, and I think it meets the definitions I've read, although I do understand there are a number of things that affect stall speed, or RPM. I don't know a lot about the engine since it was built before I bought the car. I do know I have a non-stock, "higher performance" cam?, and after market heads which may be "high performance" but that's about all I know. I'm wondering if I should go ahead and install a converter with a stall speed higher than 2400. Not withstanding the expense, will it negatively affect the performance if the stall RPM is to high? Since i'm still building the car it's a casual driver, a few times a week, and I don't plan on taking it to the track. I do tromp the accelerator once in awhile, but nothing to rough. Once again, greatly appreciate the advice. Gaining knowledge from experts is a great part of the experience.

 

IMHO unless you will be drag racing the car don't get a higher stall converter than the one you have. 2400 stall is about 1000 rpm higher than a stock 1300--1500. IDK what kind of trans you have (TH 350?) but those had 3 TC options depending on what kind of car/truck they were in. 2 were 1300-1500 (one being HD with brazed fins) and one 1600-1800 (usually trucks & vans).

With a cam and head work a 2200-2400 stall, IMHO, is about all you want on a street car.

I would consider installing a external tranny cooler unless you already have a tranny temp gauge and are comfortable with the tranny temps using the 2400 stall

 

What he said!

 

It is a TH350. I found an older guy about 15 minutes from my house who has been working on transmissions for about 30 years. He has about 15 different metal lathes in his shop and he repairs and rebuilds torque converters. I think I learned more about torque converters and transmissions in the hour I spent with him that I could learn in a life time. He cut the TC open and showed me where the builder had not done a good job manufacturing it. He explained the entire operation to me including how the different stall RPMs are obtained by bending the fins certain ways and certain degrees. He put it on the lathe and cut some metal of the fins and then welded it back together on a rotating automatic welder. He assured this would solve my problem. When put in drive the RPMs drop down to the point where the alternator light comes on. I don't kick into the throttle very often and it's strictly a street car. Awesome experience. Thanks for all the advice guys.