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What did you do with your GMT400 today...or yesterday....

I have 60 amp one mounted on the passenger inner fender for my stereo amp. also powers some extra lighter plugs in the back of the cab for the kidos to use their phoney chargers when were on a road trip! ordered it from Amazon!! lol
 
Find out what amperage the fuseable link is and MATCH IT. DO NOT GO HIGHER.
The original wire from the alternator to the battery cable is a 10 gauge wire. The fusable link is a 14 gauge. I’ll do some home work and see if I can determine what amp rating that fusable link actually is.
Might just get one of those MAXI fuse inline devices and try one of those, after I find the amp rating of the fusable link.
 
Is your alternator the factory 105 amp? You can go off what the max output your alternator is and maybe go up a tad like if it’s a 105 then go with a 120 amp link or fuse. Link wires are designed to slowly blow where if using a fuse or breaker those are designed to blow fast
 
Link wires also act as a current limiter so if the link is rated at 100 amp max you’ll never get that full load through it. Rated at 100 max might take 80 amp through it with the other 20 creating heat making the link get hot till it blows. Same concept for a fuse or breaker only happens faster. Reason I would go up just a tad on the amp rating to allow the max power but still allows it to blow on a direct short. Just don’t go up very much or when the direct short happens it won’t blow fast enough and causing fireworks 💥
 
Here’s something you can go off with wire sizes for their max rating. There’s a few other sites that have calculators for sizing loads based on automotive wiring

 
Back onto the truck.
For now I’m going to install the 14 gauge fusable link to the alternator.
I decided if that link was feeding the entire electrical system then a breaker would be in order. As it is, the fusable link that was in line lasted for over 22 years, it most likely will last that long again.
I am though thinking of installing a breaker right off of the battery, into the wire that feeds the underhood fuse/relay box. Right off of the battery just in case there would ever be a short between the battery and that electrical distribution box, or beyond.
Next question.
When I got this truck, the pyrometer probe was in about the same position as it now is in, see photo, with the GM8 turbo, EGTs would run upwards of 1200 degrees and normal driving in town, IIRC, probably about 800 or so.
Now with this ATT turbo and the 3” down pipe and four inch Diamond Eye with the muffler, temps run about 350 on the highway and IIRC, 200s in town.
Does that seem about right, or, is that low readings and possibly the pyrometer has gone bad ?
Should the pyrometer be moved to pre turbo ?
Just wondering now that I have it all exposed with the inner fender removed.
 
Pyrometer probe should always be pre-turbo if at all possible. Concensus is one of the best places to put the probe is to drill and tap that rectangular boss on the front of the passenger exhaust manifold's up pipe just below the turbo flange.
 
Pyrometer probe should always be pre-turbo if at all possible. Concensus is one of the best places to put the probe is to drill and tap that rectangular boss on the front of the passenger exhaust manifold's up pipe just below the turbo flange.
Guess I might as well take care of that while The manifold is available.
 
Ok,I drilled and tapped mine for ⅛"NPT and then put a stainless steel pipe plug in it for future use. The rectangular pad is just below where I drilled and on the out side of the manifold, facing the tire. I drilled this one where I did b/c I had easy access at the time and used my DeWalt cordless and, iirc, an N pilot bit for the ⅛"NPT tap. I was just too lazy to jack up the 'Burb and then pull the tire and fender liner to have enough room and a straight shot at that rectangular casting boss that looks like a GM engineer intended a pyrometer probe there.20220718_192941.jpg
 
Hope these help you out, @MrMarty51.
They most certainly do.
It will get done.
Also installing the electro/viscous coolant fan system.
The fan was ever so slightly rubbing on the lower right side of the shroud. An aluminum cutting die grinder bit in a right angle die grinder made quick work of that.
All thats now left is hooking the two wires to the fan system connector pig tail.
Some time back, well before Christmas I had a list of the components from Rock Auto to have the complete fan kit. I was telling my son about the conversion and he and my wife, along with the future daughter in law transpired against me, they ordered the components and handed them to me at Christmas time. 🤷‍♂️😹😹😹
Getting mighty close to having some real nice uprated components installed.
 
Okay, back to the garage. I been screwing off in the house for too long today.
My stepson owns his own electric shop. A while back he came over and installed a exhaust fan. I had him place it up next to the ceiling. Last night after the temps cooled some. Went out and opened the garage windows and turned that fan to high, early this morning, went out and closed all the windows except the one on the opposite wall to the fan, cross draft. Back out a while ago and shut that all down and fired up the AC unit. Going to be a nice day in the garage. 😹😹😹
 
Which plug is better for going into a pipe coupler fitting thats been welded to an exhaust pipe ?
Brass or steel.
I am thinking steel, I think that steel does not expand and contract as much as brass.
This will be a 1/4” pipe plug going into the steel coupler fitting.
I drilled the exhaust manifold and tapped it and now the pyrometer is pre turbo.
 
@Big T are those the bushings that need to be greased every so oftin? I have been pondering going back in and replacing my rubber ones for these and then adding a grease fitting in there somewhere. I have heard may good things about them but also have heard that they will start squeaking if not kept lubed up.
 
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