I'm debating on which air charge cooling method to go with. An intercooler system from ZZP is prefabbed, possibly requiring slight modification, and also comes with a 50mm BOV. But is expensive. The larger intercooler package from ZZP will support my closer to 600whp goal, but comes at a cost of 1200$ plus a guestimated 100$ shipping from ZZP. An intercooler also has no added point of failure, and requires no fluid.

The second option is water/meth injection. In terms of added piping, this system is way more simple. Only requiring a short charge pipe from the turbo outlet to the TB to facilitate a BOV. But, it would have to be custom. The cost of an AEM WM kit (430$), plus Tial BOV (225$), plus fabrication materials (~100$), would come out to 755$. But, I'm considering running the WM injection nozzle pre turbo, which would require a relocated MAF. Or is it possible do away with the MAF and only run on a 2 bar MAP sensor?

 

TL;DR

I'd go with either an IC or both combined.

Given you're fabbing everything else from scratch, why pay the premium for a premade IC kit? I'd just buy the size heat exchanger you want already completed, pick up some aluminum tubing and bends, and go to town welding up mount brackets and cutting / welding the piping. I'd bet you could trim at least 25% off their kit, maybe even more.

Doing water/meth only would worry me, especially at 600 whp. That engine is going to be 100% dependent on that kit to work to not explode (assuming your primary fuel is pump gas). There are also lots of failure modes:
-The cheap plastic hose breaks or pops off
-The pump locks up
-A wire comes loose (power or trigger signal)
-It runs out of juice in the tank
-Controller fails

Any one of those things happens suddenly and you're shopping for a new engine. I'd also be a bit concerned with how much fluid you're going to have to spray and if you're going to have distribution issues inside the manifold - especially if you've got a substantial amount of water in the mixture.

I love running meth, I run straight meth inj on my vette (alkycontrol kit as I like the braided screw on lines) - but it's a relatively small nozzle in addition to a traditional intercooler with some fail safes for additional protection.

If cost is such a big concern, why go with such an expensive BOV? I love Tial and have the Q on my vette, but function wise, it doesn't really do anything better than other BOVs. I get spending good money on a nice waste gate as failure could destroy the engine, but a failed BOV isnt really a big deal and you'll hear it right away. Not trying to steer you away from it, but just may be a place to save some money if you're trying to cut cost.

Any reason why? I get people doing it to alter compressor maps a bit, but as you're building this from scratch, you can pick whatever turbo you want off the bat.

It's also more risky if the atomization gets poor for any reason (kinked line, low pump pressure, clogged filter, etc) as liquid spray can cause damage.

Pre-turbo injection is not particularly common TBH.

I've not seen it done on a 3800 personally. What I'd wonder about is how fueling is done beyond the map limits. Sure it's a 2 bar sensor, but that 1 bar of vacuum, 1 bar of pressure. So what happens to fueling when it goes over 15 psi?

There are 3 bar sensors available, but our old pcm only has a limited number of cells. So now you're reducing resolution at normal driving by dividing those cells up across 3 bar. Not sure that it matters, just an observation.

 

An intercooler was my first choice, and I'll get into my reasoning behind the ZZP kit vs custom kit below. I don't want to do both, which I'll also get into below.

The main reason I didn't even consider going custom on the cold side, was equipment. I only have a DC TIG welder, with filler rod for stainless and mild steel, and an almost empty tank of pure argon. I haven't heard of a turbo car with anything but aluminum for cold side piping. Not saying there isn't any out there with stainless cold side piping, I just haven't come across it. To weld thin wall aluminum, I would need a new gas cylinder full of pure helium, and while it may be possible to weld it with my DC TIG machine, it wouldn't be easy. I'd also need a bead roller for the ends of the piping, and tons of T-bolt clamps, which get expensive fast.

I do plan on keeping it on 93 pump gas, and I understand there are a lot of added failure points. I'll definately be adding as much of a failsafe system as possible. My reasoning behind not doing both systems is obviously cost foremost, but also saftey concerns. If I injected the WM before the intercooler, I've read there's a posibility it could condense in the cold side piping, especially the intercooler. If I injected it at the end of the cold side piping, it negates the reason I want to inject it before the turbo, which I'll get into below. An intercooler plus associated piping is also lots of volume the turbo needs to pressurize before the engine actually sees boost, which is a spool time issue. What would cause a distribution problem in the mainifold? To run a mixture with less than 50% water, I'd need an alkycontrol kit, or something similar, thats rated to withstand the percentage of methanol. The AEM kits are only rated for 50% methanol.

The reason I want to go with Tial over a differnent brand isn't function, it's quality. The Tial Q would very likely be the only BOV I'd ever need for this build, not to mention the only flange I'd need to weld. But if I bought a cheaper BOV, theres a higher chance it could fail.

The reason I want to inject the WM before the turbo is bassed on the following concept. Compressing air creates heat, which is why an air charge cooling system is needed. But, if you inject WM into the air before it's compressed, the boost coming out of the turbo is colder, therefore denser, than it would be otherwise. Theoretically, this means the same turbo can compress the same volume of air, but with the WM it would result in a denser volume of air. Meaning the turbo would have to work less in order to output the same amount of oxygen. Additionally, whether it's needed or not, it would also keep the temperature inside at least the turbo's compressor housing down, possibly also reducing the heat added to the oil.

I don't plan on going above 15psi. Especially not on my very high mileage bottom end. If I do eventually end up wanting to go above 15psi, I can cross that bridge when I get to it. Plus, I wont have the fuel system for it. For the initial turbo build, I'm sticking with the stock fuel system. To effectively go over 8psi, I would need a boost referenced fuel pressure regulator. I'm also eventually going to need 80lbs injectors, and probably a fuel pump upgrade. What I don't know is if, with tuning of course, it is possible to only map the fuel tables on a MAP sensor, when the PCM was designed for a MAF/MAP combination.

 

Ah, my bad, I assumed you bought a welder that could do anything. That's too bad. Theyve got complete universal piping kits for about $100 on frozenboost, just need to cut and weld them together

TBH then, I'd just skip the alky/meth altogether and just do the IC. Your power goals are extremely high, so it's going to lean heavily on alky for cooling. Theres no failsafe that's going to save the engine relying that much on the alky - any system failure and it's over.

You dont inject it before the IC, I'm suggesting you do it via a TB plate like the nitrous people do. Zero risk of pooling/ condensing doing that.

I wouldn't worry about spool time too much either. Turbo selection is going to be the main driver of that anyways, and you can pick whatever turbo you want doing a custom setup.

Realistically though, at 600 whp, it's not really going to matter. You can brake boost out of the hole (and will blow most tires off anyways outside of drag tires), or you can brake boost from a roll. It's not like you're going to be auto x or road course racing it where you'd really be concerned about immediate response.


A large amount of liquid being sprayed in. It's not designed as a wet manifold, so theres no consideration to keeping atomized liquid in suspension. If you're just doing normal amounts, its NBD, but if you're talking nixing the IC completely, you could need a lot of alky to keep temps reasonable at 600 whp.

If you're going that route, I'd go with a kit that let's you run either. I started with my vette on boost juice (about 50/50), but had much better results on straight meth. No doubt, it's a totally different application - but it's nice to have the option to play with that variable also.

Totally get it. Just suggesting it since it sounded like you were trying to cut costs as much as possible on this. You could break 2 or 3 cheaper BOVs before it breaks even.

Completely understand what you're trying to do, but just saying that's not the normal way of doing it. Most everybody I've seen on 3800s and LSs starts with a single or dual nozzle in a TB plate or in the end of the charge pipe (for external MAF setups). Certainly some run an additional small nozzle up there at the turbo, I've just never seen anyone do a giant nozzle (like I think you'll need if that's your only cooling method) up there only - at least on a street car.

Not sure why youd bother setting the car up for the short term if the goal is 600. It's never going to get 600 on 15 psi, so I dont see the benefit of modifying to run MAP only if you may need to change back to go further.

TBH, the pre turbo injection is the oddball thing that would cause the MAF problem in the first place. If youd just use a plate like everyone else (at least for the majority of the volume), this wouldn't be an issue at all.

IMO you need to contact your tuner before jumping into this to see if they'd even reccomend trying a SD tune on our crappy PCM on the 3800. That whole path maybe be DOA and not even worth going down. I'm just not familiar enough to know for sure.

 

At this point, as much as I like the idea, it does seem like the WM would cause complications.

I'd love to run an alkycontrol kit, but it seems like they only have make/model specific kits. I couldn't find a universal one. Or really read over the instructions to see if I could adapt one of the kits.

My point with the spool time thing was that WM would be the primary means of cooling the air charge, so an IC would just be added volume the turbo has to presurize, with deminishing returns.

I picked out an ebay turbo with the same specs as the turbo ZZP uses in their Stattama turbo kit.

How have other max effort turbo builds measured their boost? With a 3 bar MAP and stock MAF?

I went ahead and tried sourcing all the materials I would need to fab an IC kit with tin wall stainless steel pipe, instead of aluminum, since thats what I have equipment for. But like I suspected, it's not cheap. This is just material cost too. I'm going to need more gas for the welder, and this also adds lots of time to the build. I'm not trying to meet a deadline or anything. I'd just like to get some progress in.

Custom IC Kit:

-Mishimoto IC: 279$

-2.5 to 3” Couplers x2: 22$

-2.5 to 3.5” Coupler: 12$

-

Tial Q 50mm BOV" target="_blank">Tial Q 50mm BOV

Tial Q 50mm BOV">Tial Q 50mm BOV" /> Tial Q 50mm BOV">Tial Q 50mm BOV

: 220$

-180* Bend: 35$

-45* Bend x8: 116$

-4ft Straight Pipe: 45$

-3” T-Bolt Clamp x2: 10$

-2.5” T-Bolt Clamp x8: 32$
-

Tubing Beader" target="_blank">Tubing Beader

Tubing Beader">Tubing Beader" /> Tubing Beader">Tubing Beader

: 152$

Rough Total: 923$

 

I think you'll be happier in the long run being able to just hop in and drive without worry with an IC. You alky idea is totally valid (although I'd dump most of the liquid via a TB spacer and just a small amount pre turbo), its just kinda like nitrous in that when something breaks (leaning that hard on it) that it's often catastrophic.

Stock 2 bar MAP and some kind of replacement MAF - LT1, slot LS, etc. They just let the MAP peg as fueling is going off the MAF on a stock setup.

Yeah, stainless is a killer, and theres no upside at all to running in a comparatively cold intake side application. Itll be a lot heavier too.

You could probably make something work with standard aluminum finished bends and tubes and a bunch of couplers, it would just suck having a ton of extra potential spots for boost leaks and such.

I dunno, dont really have a good suggestion beyond just buying the kit.

 

Yeah, I agree it would be a more piece of mind setup. The main reason I started looking into the WM stuff was the cost of the large IC kit from ZZP. But the thing with fabbing my own, or even buying premade pipes and a bunch of silicone couplers, is I don't really know the routing the IC piping takes. So I dont know the bends and lengths of pipe needed. I think for me the easiest option as far as ease of installation, would be ZZP's kit.

Then I would need a 2 bar MAP, and possibly an upgraded MAF. Along with the PCM tuning to run them. Is the MAF upgrade necessary because the stock MAF doesn't support enough fueling changes for a high boost setup?

 

I guess I should note that it's not really a requirement, just more common. As long as the MAF is functioning, it doesn't really matter TBH. It does let you include boost level for much of your boost curve while scanning.

The MAF upgrade is the important one as that is what determines fueling.

There is a frequency cap that cannot be exceeded. The air velocity past the sensor is what creates this frequency output. So if you need to flow more air and your MAF is pegged, you just move to a larger diameter maf/tube as thatll yield lower velocity (and Hz) at the same airflow level (and obviously the MAF table will need to be modified as well).

I'm not real familiar with the power levels where a new MAF is needed on the NA TBs, but certainly at 600 whp you'll need one.

 

Okay, I've actually saved up enough, and I think I'm just going to go with the smaller IC kit from ZZP. Since I won't be running the turbo kit at 500-600whp right off the bat, I'm thinking about just going for the smaller IC which is cheaper. Then once I get the fuel system, and air monitoring up to par, I can just upgrade the IC to a Mishimoto core. I know the counter to this would be, "if you're going for a max effort build, why not just save for the larger IC?" I am shooting for a max effort build with this car. But I don't have the money to get straight to it. With COVID-19, hours are starting to get slim. So I'm working towards that end goal. The piping is what I really need from ZZP's kit. There isn't any branding that I know of for the IC core and wastegate. So once I max out the smaller IC core, I think going for a nice Mishimoto core would be a better option both for my budget now, and in the long run, for the build quality.