[dezldave961]

The rear manifold in stock or Plog form isn't optimal for turbo on the crossover, but works. H-body offset downpipe outlet doesn't really matter when you're using the rear manifold outlet for wastegate perch, so swapping to a W-body style is feasible. The wastegate is just being dumped from there, and the turbo downpipe is now what you have to get routed through your firewall tunnel for the cat-back.

It looks like they squeezed just over 400 from their example set-up with a big cam and HV3, so I'd say that should be around where you may see. The Z3 isn't my favorite design, due to the routing path they could easily re-tool at the same fabrication costs, but it's their budget version of the Cartuning design.

 

[dezldave961]

In turbo configuration, the rear manifold doesn't care what chassis it's in. The rear outlet is offset differently to send the regular downpipe thru the firewall tunnel. When you go turbo, the rear manifold is now sending the flow up thru the crossover "inlet" to the turbo flange.

If you look at my photos of the Stattama kit mock-up below, you'll see how the "turbo rear Plog" eliminates the outlet (no longer cares if the outlet was an H or W placement). For the Z3 kit, that outlet is used for the wastegate to bleed off excess exhaust pressure to not spin the turbo too fast and control boost level. The wastegate is routed internally on the Stattama (and older Z7) turbo kits after bleeding pressure from the rear half of the crossover.

The actual downpipe now exits from the turbo exhaust outlet, and routes down the firewall tunnel. This may be the only interference spot you'll need to ensure is clear during install in an H-body, depending on how things go.

Benefit of the bigger kit is higher power potential, and a more deliberate routing of the turbo pipes. I'm sure you'll be happy with the basic kit, but if the bug catches you... Who knows.


For suspension, I've never messed with H's there. A few new posts here have been going into that, so hop over to those for more info.

 

[dezldave961]

For the Z3, you need one with an outlet of some sort. The turbo version of the Plog won't have a place for the Z3 wastegate.

 

[dezldave961]

You're on top of most things from the sounds of it. That all sounds like a boatload of work that may take the whole year to knock out.

For pics, I have luck using the image icon in this typing menu for in-line uploads for my phone or a site. Unless it gets mad about a high-res photo from my phone, things usually paste fine (which is why I like using it a lot for describing things).

For builds like this, you're honestly best to get your hands on tuning yourself (referencing the other post, but trying to consolidate the discussion here). I know it seems like a big thing, but if you want to be able to tackle any changes and really know the car, that's a crucial step. Plus, it builds your troubleshooting skills for any vehicle 10-fold. Getting on a dyno is usually the final step, anyway, since you have to crawl-walk-run (idle-cruise-boost) your way to a thorough tune that's comfortable.

 

[dezldave961]

Honestly, even though ZZP can be a bit dry to interact with, their remote tuning option to get started seems like the best route right now. You'll get a baseline tune that should get you rolling, see what they request for data to monitor, and be able to compare files they send back and forth as you upload them yourself. This then provides the option to keep the hardware (laptop, HPT cable) to continue from there as you explore, from what i gather. Check out their YT video from 1-2yrs ago where Tim explains the process (~45yr old white guy with salt & pepper goatee).

 

[dezldave961]

Pont arrows on HG's towards "front" of engine (water pump end). Looks like the one on your front bank is backwards (side with A/C). I forget the exact difference that drives this, but I think it's very minor.

Not trying to self-promote, but check out my 2020 build videos (kinda boring, but I tried showing the boring details). Also, Terrell Smith does some decent coverage in his Bolt for Bolt videos, although he also isn't a professional charismatic presenter, either (we can't all be Cleetus).

 

[dezldave961]

I think the only difference is the size of water ports that somewhat guide the flow. I've always installed them based on the arrows on a bunch of engines, and yes there's a minor difference in the ring, but both sides are up against flat cast iron.

 

[dezldave961]

Wow, miles of space in there. Looking good, just take your time and keep doing things as clean/correct as you can, so you can feel solid about the way it's assembled.

 

[dezldave961]

After you get things mounted, vac lines are important. I did a bunch of google hunting when I re-routed everything during the shutdown and wound up going by the Tial manual for how to do it, and customized it for my setup. Just ask questions about whatever step you're at and we'll try to help.

 

[dezldave961]

You need to block a few things to not have boost going to the wrong places now that it's made before the M90, not after... Mainly PCV passages. Fill the top of the PCV valve (vents into M90 case) with RTV and plug the path to the TB (fresh air draw before blade), so you're not boosting the crankcase. I'd also find an angled oil cap elbow to get the breather vertical (swap front and rear valve covers for appearance fun).

Also, I would remove the lift brackets, EGR (delete), and the boost bypass (remove blade from inside and secure position tab down).

Looking good, keep at it.

 

[dezldave961]

EGR puts hot crud in your intake, and is useless for the original purpose, as well. That's why they help you delete it, with the safety suggestion that you don't "have" to.

PCV path is as shown:
Red - vent thru PCV valve
(pull valve and fill top w/ RTV)
Green - fresh air drawn between TB blade and MAF
(plug by filling with RTV or drill/tap/plug... Light green circles in previous pic above)
Blue - tube for Green path on Series 3's
Yellow - pressure/fumes in oiling system below pistons

Lift brackets are just those black painted brackets bolted to the exhaust manifolds that aren't needed except when lifting the engine out. They tend to get in the way when doing other things, and just look dumb.

Boost bypass is the black plastic cylinder on the front of the M90 that runs to the vacuum tree, and has the little 2-wire connector to the little solenoid bolted to it. While it really won't affect anything now that you're going turbo instead of s/c, it's extra things in the way. Maybe just leave it for now, but make a plan for later, maybe going to an L26 or F-body intake.

 

[dezldave961]

You still need to address the PCV passages similarly on an L36/L26, because it's on all 3800's (you had an L36 Series 2 if it's the plastic one, so I don't suggest going that route if you don't have to.

Later on, maybe shop for an L26 upper/lower intake at the yard, and prep it more (block TB coolant passages, port side coolant path, maybe gasket-match ports, etc.)

Same path descriptions as M90 version above.

 

[dezldave961]

For the PCV valve, just sacrifice the valve and pack RTV in the top of it, and place it back in there.

For the TB, that path goes from that rear hole forward, then turns up to access the main bore just ahead of the blade. Just find the best way you want to plug that path with the simplest, cleanest method you have access to do.

 

[dezldave961]

PCV looks great, just be sure to reinstall with spring like stock, so that o-ring has pressure to stay sealed underneath.

They have 90deg fittings for that, although not the best for your primary sensor (usually used to get rear sensors to read less when using a hi-flow or no cat).

Maybe consider trying it in the original spot, if it fits, or else you may need to get that fabrication done.

 

[dezldave961]

There's the TB ports that go thru the LIM/UIM next to the EGR port that tend to leak past their o-rings. I always try to plug them by tapping for 1/4" NPT pipe plugs that have allen sockets (brass in pic below).

Being close to the EGR tube causes the gasket and UIM to warp, enabling leaks in this area. An L26 aluminum UIM helps, but all items in that zone should be deleted for best results.

(Supercharged example I found quick, but same ports.)

You should also open up the side cap to improve the coolant passage between front and back heads, especially when plugging the TB passages.

(This guy went a little overboard, but you get the idea.)

 

[dezldave961]

My email is same name at gmail, if you want to get into your specifics more (didn't go anywhere, I'm the most active guy here the past couple years to keep the platform active, you just didn't ask questions while stating things in recent posts).

The turbo isn't really going to be the draw, more likely the intake vacuum draws it and sends it thru the engine and out the exhaust, which passes thru the turbo hot side.

 

[dezldave961]

You are all about pulling the turbo for some reason. Coolant doesn't run to the turbo, unless you have a ball-bearing center section with coolant ports. Anything going thru the turbo is because something is not right at the engine.

EGR takes 5min to get off, and you ignored the supplier who gave you the parts to block it when you were installing. A 10mm Gearwrench or 1/4 drive ratchet will get back there to unbolt it (you may have to add some leverage to crack it loose, and possibly pull downpipe to get space).

You asked a bunch of questions I answered already, regarding plugging the coolant passages, and I suggest you use appropriate decision making to determine what to replace if warped. Diving into engine work means you're signing up for some decision making, and only so.much input from others can be applied, since we can only hear part of the situation on the other side of the screen.

 

[dezldave961]

As someone who gets info from the biggest 3800 vendor, and echo'd suggestion with reasons from a 3800-based forum, you still installed the EGR on a turbo setup. That doesn't indicate someone who's looking for input, moreso just wanting to display their project (which is fine) and validate their choices already made.

You're free to do what you want, it's your car. You asked what parts might cause coolant issues, it's most likely intake manifold-related due to the reasons already discussed. If you need to re-read that, and think out loud to get it, cool. Immediately replying to re-state things you clearly comprehended (but didn't want to agree with) doesn't do anything to advance your troubleshooting.

Have you unbolted the UIM to look at the o-rings, yet? Have you done anything physically since I posted those images of exactly what I was talking about? My reply was carefully built as I Googled basic terms to get the images, and put them with descriptions of what I was saying. Any further words wouldn't have additional info until you take some steps to inspect/work on it more.

 

[dezldave961]

Related to your project:. Continue posting pics of your steps, and maybe we catch something in the corner of our eyes.

Off-topic:
Bud, I post here simply to keep the lights on in the community. If I didn't want to help, I wouldn't spend 5-10-15min digging up clear photos and scratching my brain while deciphering posts/questions for what's going on. I took the day off, too, and also check here randomly (almost) daily with the New button, to make sure people aren't hearing crickets.

There's only a couple sites left for this stuff, and most members haven't experienced the full cycle of 3800 mods/reasons/issues/etc., so I try to dig thru my 20yrs of cobwebs to ensure people get some budget-friendly fun out of these cars while they last. People tend to get into 3800's nowadays because they can't afford something more modern/faster that's got more aftermarket options. We all have our excuses of "unique" or "challenge" and so on, but we all have an honest story behind why we have a 15-25yr old family sedan and decided to throw a couple parts at it for giggles. Barking at another person at this level does nothing to advance it, and will discourage you more than anything.