I need to know what grade of replacement nuts to use for mounting the turbos and downpipes. I have the APS kit which uses those crappy copper lock-nuts, and I want to replace them all since there are a few that are rounded off.

Just need to know what grade of steel will handle all of that heat and stress.

 

i replaced mine with grade 8 ones.

 

Grade 8 in metric is about equivalent to grade 5 in standard, or so I was told. Do you guys think that is strong enough? I'm only doing this once, while the motor is out, so it has to be right the first time.

 

they will be plenty strong,plus id would also use some loctite.

 

Thanks guys, I went out and got all new nuts for the turbo flanges and downpipes.

I'm a little hesitant to use loctite on those, since they're so hard to get off in the first place. I'm just going to use lock washers.

 

yeah just use lock washers, i hate those soft lock nuts aps supplies with their kits. i shredded all of them.

 

loctite will not hold up in the temperature, and a lock washer will loose all its tension after a few heat cycles.

Just the other day at work I was putting the GT turbos back on a Noble M400... one of them had actually damn near fallen off due to the hardware that was used before (be previous mechanic), which was metric 8.8 nuts with lockwashers. this car sees the race track every week so it needed something better... go to www.mcmaster.com and put in part number 94560A080 , i replaced all the turbo hardware with those and new studs.

they are rather expensive but very high quality and durable, they wont round off on you like those copper ones.

 

Thanks phunk, but you're a little late this time, haha. I already have pretty much the entire turbo kit re-installed, and everything else except the wiring harness. Hopefully these will last me until the winter when I'll hopefully be sleeving the block and upgrading turbos.