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BUILD The misadventures of sktchys turbo 3800 catfish

sktchy3.8

it'll work til it doesnt
TCG Blue
Jul 27, 2021
3,776
6,470
I had to take a step back from it for a bit before I end up tearing all the wires off and wrapping everything I can without taking it off so I'm trying to put a process behind some thoughts I've had about boost control. From day one I've wanted a stupid scramble switch in this thing and in theory I think I can do it for pretty cheap with a simple 3 port Mac valve and a little wiring. I've already got a manual boost controller to throw on one side of it but wouldn't this kinda setup work for what I'm trying to do?

I don't see any reason to utilize the top port of the gate where there isn't any sort of controller to monitor and regulate boost of the sense it would normally operate so basically I'd be using the valve to switch from a full on reference line to a line that's restricted by the mbc.

It seems simple and kind of primitive but like it would work. And now I'm starting to think I should just tap my compressor housing for a reference because pulling vacuum on the gate maybe isn't ideal?

It pissed me off so now I'm rethinking everything.

Screenshot_20230525_210649_Samsung Notes.jpg
 

Mr_Roboto

Doing the jobs nobody wants to
TCG Blue
Feb 4, 2012
22,745
24,303
Nashotah, Wisconsin (AKA not Illinois)
And now it just wants to misfire all over at idle. Haven't even gotten to drive the thing. Gone through the wires and can't find anything. Tightened a couple of the coil pack bolts a little after one of the packs shifted on me messing with wires. Changed some stuff in the tune. Still missing like it has a cooked wire. So back to it's usual bullshit.

This car is as toxic as any girl I've ever met 🙄
My fucking lathe has been like that the last week or so. Breaking gears and the chuck won't come loose. a time suck, money suck and patience suck.
 
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sktchy3.8

it'll work til it doesnt
TCG Blue
Jul 27, 2021
3,776
6,470
That's where I'm at. This thing whipped my ass all week, had it sounding and running awesome and then I didn't even get to drive it without more bullshit. Anything else I can diag and zing right in and out the door but this one fights. And when you finally think you've got a breakthrough on one thing and your making progress it swings around and slaps you in the face with another game of pin the tail on the problem. I

Not a damn thing in the world has taught me patience and humbled my ass in ways this thing has.
 

sktchy3.8

it'll work til it doesnt
TCG Blue
Jul 27, 2021
3,776
6,470
Couple minor breakthroughs, while this car does seem to use the ve table I decided to zero it out to know for sure. This has forced it into a maf only condition and it's flashing fuel in way easier and timing is more stable at idle. Wild. I won't know how it effects transient fueling or decel until I can run into town and put some fuel in it but to know that for sure I'll have to change my stock decel settings back and play with that as well.

The other thing I found that's probably more useful. Misfires can only be read during a certain rpm range that I had to drop down to for them to start showing. For me it was 775. And the junk wires I tossed on 3 and 4 out of the bucket must suck.

So it's little progress but at least it's forward momentum and now I guess I get to wrap what I can of these pipes and throw that set of msd wires I have on it and hope they don't burn since I'm down to the bottom of the bucket when it comes to take offs. If I cook those I think the accel ceramics for a 4.3 pickup are gonna be the move since they come with both straight and 45 boots.
 

sktchy3.8

it'll work til it doesnt
TCG Blue
Jul 27, 2021
3,776
6,470
And here we go, I start taking the turbo blanket off so I can get a look at everything and start wrapping it and I get another stupid idea. Maybe if I put a different housing on I can get away from that filter housing and help even more with heat and increase the spool at the same time. A little bit of experimenting follows.
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The precision .81 housing fits on the old turbo I blew up and spins just fine. The brackets fit but the threads for the bolts are different, no biggie I have the bolts. But the precision housing isn't going to gain any room. The .68 housing seems to be my best bet as it's shorter than even the flatter .96 housing on my china clone of the turbo on the car. I feel like it's also in a lot more reasonable range for my goals with the car and should help spool a good bit.Snapchat-1576593177.jpg Hopefully I'm right because I might try and fuck up another good turbo if it doesn't go well.

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