Slow Z28

iTrader: (19)

Alright, had a few people talk to me about why my shortblock blew. I haven't taken the motor apart yet, but i dropped the oil pan(not out of car yet though) and i can hear stuff rattling around, and the motor is locked. A few people have said that the huge converter i have, the TP4400 w/ 2.86 STR, may have been a cause of it. Why would that be and how would that happen? I took care of the motor, only 50k on it and never used a drop of oil. used Redline oil all the time so it wasn't me spinning a bearing. shifted at 6200rpm in a bolt on car. Any thoughts or info?

Chris

02 Silver Z

iTrader: (8)

ttt for ya. I have a TCI 4400 behind a untouched motor so I`m interested. I don`t see a connection between the two other than the fact that with these converters our obvious intent is to beat the hell out of these cars. Maybe yours was not assembled properly from the factory? You don`t hear about these LS1`s letting go to often, but, sometimes things break. After all, it is a mechanical device.

sited12

I have a set up alot like yours Z28 kid so i am interested. I know huge gears put alot of stress on the bottom end but not a torque converter.

Michael Fornal

Heh, I just asked the same question before I read this. Stupid me.. I'm gonna quote in this post what I wrote in the other one and then delete that thread..

edit(my thread i deleted):
Heyya folks,

I've been recently seriously contemplating a TCI Comp 4200 stall for my car. I figure why get a small *** converter, when you can get a bigger one that works better?

But anyways, I was talkin' to my best friend about it, and he basically said I was stupid because it would destroy my engine quicker. His reasoning being that the TC keeps the engine at a higher RPM and puts more stress on it.

So, is he right.. or would running a midwest 3600 be the same amount of stress as a 4200? Aside from obviously the car being more loose feeling, is it more dangerous to run the high stall?

BTW, it's a 2002 A4 daily driven. I don't mind having the loose feeling, but he's got me worried about longevity compared to a lower stall.

Thanks for any help.

<small>[ March 09, 2003, 04:45 PM: Message edited by: Michael Fornal ]</small>

sited12

If you go fast parts will break. So yes over time the high RPMs will take their toll. But I honestly dont feel that there is a direct line we can draw to the high stall destroying short blocks.

Slow Z28

iTrader: (19)

mine blew asi was coming out of the water box. split the block as well cause there was a ton of coolant in the oil. anybody shed some light on this? i wasn't spinning this too much higher than stock. No one else seems to be having this problem because of the number of these converters running around. i love the converter, and want to put it back in, but a bit on the sketchy side now.

Chris

Slow Z28

iTrader: (19)

alright, talked to someone who is pretty knowledgeable about it, and has seen other cases of it happening.

basically, when you are in the water box and full throttle, the converter is exerting all it's force through the drivetrain to the rear tires. but when you let off, and the rpm is coming down, it puts all that stress forward. the motor is slowing down but the converter is still trying to spin as fast as it was before. because it isn't like a locked system. so that stress on the rod bolts is very heavy as the crank is slowing down against the converter(hope you guys get what i mean when i say that). and it's especially true at areasunder the stall rating with such a high torque multiplication/STR. so that's probably what my problem is, broken rod bolt(s).

it was pretty hard to keep up with him as he talked on the phone, so i may have not worded this correctly, but i got the jist of it. basic solution.... get some arp rod bolts and don't worry about it.

Chris

Pro Stock John

iTrader: (34)

I think you stretched some rod bolts and motor died shortly thereafter. I see motors here and there do this. I see it being RPM related, plus if you have a lot of runs on the car the motor is working hard.

If you need a cheap shortblock let me know I will put you into the next deal, there was one in OH for $600 that was a nice deal.

Slow Z28

iTrader: (19)

i see that as a definite possibility as well because of some misadjusted shift points at one time(2 runs).

thanks for the offer as well. i got a line on a shortblock for pretty cheap, but i'm trying to decide what to do with the car and if i want to build it up any instead of the '94 like i had planned.

Chris

Michael Fornal

Okay, so.. a high stall converter is bad during burnouts especially?

What if you're just drivin it daily and race every so often, and get on it quite a bit?

Is there gonna be much difference between a lower 3500 stall and a 4200, as far as tearin' up the engine?

Slow Z28

iTrader: (19)

it could be a number of things. there are plenty of people that haven't had that problem. i just had been racing on thursday, then saturday, and then tuesday, probably 20-25 passes total those three days. so that's a lot of stress. but i was told that a lower stall converter like my old 3200 wouldn't have had as much impact as the tp4400 i have in there now, and also because the str of the smaller converters is less. vig3200 i think is like 2.1. so many factors like what was stated earlier.

Chris

sited12

I agree on the slowing down of the crank when you let off out of the water box. Thats what i meant when i said bigger gears. When you let off at the end of the run the gears keep the RPM up and the motor tries to slow down. This is the reason you should stick it in neutral after the run and use the brakes or the stress will make some nice windows in the block.