Hope everyone is having an awesome Holiday season so far! I have a 1985/86 Mini Cruiser RV with a 22RE. It is on the 1985 1 ton chassis. These questions seem like they would fit somewhere else better, but I didn't find that spot. This described my chassis the best though.

I am looking to add boost to improve fuel economy, and power. Well versed in turbo installs (but not on these Toyotas) and MegaSquirt engine management. I don't know much about Toyotas CT20 turbos that came on the 22RET. I can't find specs listed for them and it seems that the ones on eBay are all the same except for the intake attachment and a round ve rectangular exhaust port.

There are limited choices for exhaust manifolds though. A vintage factory cast manifold that comes with vintage and likely to break bolts... A CT20 manifold with individual runners and no wastage port. And a log style T3 with an external wastage port.

I am concerned about the quality of the two eBay China manifolds. But getting an old OEM cast manifold will be more expensive out of the box and probably need work at the machine shop too.

I also don't think I want to limit myself to the CT20s apparently limited range of options, if any. I would be okay with an adapter plate for the CT20 manifolds. Anyways I could use some direction and guidance here!

 

I don't see adding a turbo making hardly any difference in a 22RE motorhome.
Most Toyota RV owners are displeased with the power at take off.

 

Factory sized turbos do tend to be small and boost happy off the line, hence my concerns with the CT20 and thoughts leaning towards utilizing a T3 mounting. I have plenty of off the line power (for a motorhome), but it runs out at higher rpm. Topping out at 55-60mph with no chance to pass isn't really safe on modern highways. Where I am the speed limit is 70mph. It would be nice to be able to get up 80-85mph and be able to actually utilize the overdrive. Let's ignore the fact it's probably going to be scary going that fast in this, but if I can get there I can at least get out of a potential situation. And comfortably cruise at the speed limit of 70mph.

Somewhere at 50-60mph I am also likely hitting an aerodynamic wall. I haven't driven it far/long enough yet to know where exactly this is, but the fuel economy will plummet when I hit that wall. A turbo is more for fuel economy in my situation, than a quick 0-60 time. Once everything is in, I have a Perfect Tuning gauge and should actually be able to see that "wall"!

None of this is exactly practical. But I have no boosted vehicles right now, and a serious boost addiction! I have built plenty of turbo setups over the years for power, but discovered that when turned more mildly and sized correctly, MASSIVE fuel economy gains could actually be had. I have a kinda silly goal to see 20mpg in an RV. And the only one out there even possibly capable of this, it the little Toyotas. Will I succeed? Who knows. But zero chance of success if I don't try! And I know for certain that I can improve on what is currently going on in the power and economy department.

No, I will not be doing this on the Toyota engine management. I am fairly confident I can see a 3-5mpg increase just dumping the OE management, eliminating the restrictive AFM, getting modern injectors installed, a wideband, and proper tuning. I already have everything on hand to do the MegaSquirt conversion, including a fully specd out MS3. I also have tons of random turbo installation bits and really only need the manifold, turbo, and probably an intercooler.

The MS3 conversion will happen first. But I was also hoping to get a start on collecting the remaining turbo parts.

That leaves my big question on the quality and durability of the ebay china manifolds. An OEM Toyota one would be nice, but again old with old problems. I suspect the T3 log manifold would be the next most durable choice, but horrible flow and I don't need or really want the hassle of en external waste gate and plumbing that back into the exhaust. That leaves me with the CT20 manifold with individual runners. Or pushes me back to the OEM one. Unless I find one dirt cheap, it will easily end up 2-3x the cost once it is cleaned and studs replaced. I have broken way too many exhaust manifold studs over the years. I probably won't give it more than a halfhearted attempt, before taking it to the local machine shop.

 

Well, good luck. I still think anyone unhappy with the engine performance of a RV on a Toyota platform should buy one from a RV company that used a engine/trans/frame from a manufacturer that intended this kind of of use, like the Ford E450 V10. Mileage isn't any better, and hills are still a drag, but you do have some acceleration and power.

And no, I have zero confidence in anything from China, Taiwan, or Korea.

 

The OEM log style manifolds are prone to cracking and restrict flow. I would not trust any China manifolds. LC Engineering makes a manifold but it is expensive. For a time vs money argument you will be miles ahead swapping in 1uz v8. I suspect that at higher speeds and rpm cruising you will see terrible mpg due to the engine boosting continuously. This effect is seen with the eco boost v6 trucks. Unloaded they do great on mpg but towing a load the fuel mileage suffers greatly due to the engine running under boost for longer amounts of time.

 

"Unhappy" is relative... I have spent many years building and tuning cars for myself and customers. I can't leave anything alone. I don't think I have owned a single car in 20yrs I haven't fairly extensively modified. This is something new and fun to mess with and learn about, so I dove right in. And I know I can greatly improve on it.

The Ford V10 motorhomes are okay to drive power wise. But they are considerably bigger and heavier too. And they are NOT FUN to work on. Parts are hard to come by, and everything in the engine bay is covered up. To do practically anything, you have to pull the doghouse. Changing injectors, a SUPER common issue, is a long and painful nightmare. They are uncomfortable for the passenger as the doghouse intrudes into the foot space. Then there is the mileage. It is ATROCIOUS. If you have the engine working perfectly (most aren't) then they get 5-8mpg. Downhill with a tailwind on a cold day, maybe 10mpg.

Yes they do have a lot more space inside and one could easily RV/live full time in one. I am not doing that. I might go camping a few times a year, and plan on 1-2 longer raodtrips a year. I want a vehicle I can pop the hood and get to anything. The Toyota is perfect. Headgasket replacement in the rest stop or Walmart parking lot? No problem!

Anyways the Ford V10 has (new) 265hp. On a heavy platform (10-13,000lbs). Getting 5-9mpg. It has a more modern EFI system on it, so modifying wouldn't be worth the cost vs return. And it is NOT a joy to work on.

The Toyota 22RE has, well no power but on a platform half the weight (5.500lbs). On the Toy forums, we have seen trip reports of them getting 13-16mpg. It has an archaic EFI that can easily be massively upgraded for minimal cost. And it is an absolute joy to work on! Getting the 22RE somewhere around 175-200hp, shouldn't be too difficult. Sure, old Toyota parts probably aren't sitting on a local parts shelf either, but they are way more reliable to begin with. And parts are cheap.

Okay good to know since I was really leaning towards a Hilux OEM manifold. (I already put an offer in on one, but seller hasn't accepted it yet.) The LCE options are pretty nice. Expensive, but nice.

Yeah that's not happening. I can do a turbo install before the wife realizes what I am up to. She would notice the donor car and empty wallet. I have lots of parts left over from many prior turbo installs. I really only need manifold, turbo, and intercooler. Have everything needed for the engine management collecting dust on a shelf.

Turbo sizing is the key here. Getting the RPM down and putting more power in the off boost areas of the map. If it is sized right, you will be sitting at 40-55kpa when cruising on the highway with pretty much instant boost tip in when you open the throttle. For instance cruising at 3000rpm, and boost kicks in at 4000rpm. This is practically a black art... But it is really fun! The trick is to have the turbo "off" as much as possible and beef up the low end range of the engine. A cam swap, tunable maps, and eliminating the Vane Meter do wonders for this. A rear end gear change could also be a smart move.

Currently, I don't have the MegaSquirt installed. I want to get a baseline before I do. I am thinking I might grab a cheap tacho so I can get a feel for the actual shift points and power band of the slush box. But once the MS is in, a tachometer won't really be needed as that Perfect Tuning gauge can do everything.

It is also possible there is actually something wrong with the truck right now. Getting a random pop now and then at idle once hot. And it stinks. I think the EGR is sticking. I will delete that long before I spend any real time to diag it.

 

I say do it. I don't know if you'll gain much in mpg but more power will definitely be a plus. Regearing might be an issue. I thought I remember reading that those dually axles are not normal 7.5" or 8" axles and not much is available for them. Maybe try a different tire size? For a manifold, I would look into a custom one. LCE sells a header flange and then it's just getting the tubing and the turbo flange fit up and welded. I would also go with a T3 flange just because they are way more available with better options and much newer technology than the toyota ct20 developed in the early 80s.

For years, I've kicked around the idea of a MS system just to see what could be gained over the 30+ years of technology advancement over the stock system but I decided to go the 3rz swap route instead.

 

This right here! Getting rid of the AFM is going to be a huge difference. Modern multi hole atomizing high-z injectors. Wideband oxygen sensor. The ability to lean burn tune the engine in cruise. The ability to safely tune boost to learner numbers. Modern ignition systems. And a whole slew of other things. I honestly believe I can break into the 20's. Probably won't be deep in, but I am almost certain I can get it there.

Tire size is SUPER LIMITED for the 14" wheels. There might actually only be the one size still available. 195 R 14c Load range D. But that is already a size up from the 185 R14 that were on it when I got it. New tires, and I also have 7 matching wheels. Getting these wheels is near impossible!

But it seems re-gearing the rear end is pretty easy. Pulling axles on mine probably sucks, but just gotta swap the whole differential assembly after that. No adjusting gear lash etc.

Manifolds... This is going to be the deal breaker. So if I could find a factory manifold (one on ebay right now) a CT20 setup with all the bits and bobs comes to $700-1000. The LCE parts list with a T3 forces me to use more parts and comes to about $1800-2000. Building a manifold is beyond my capability and of the tools I have. But if I use the bag of snakes eBay CT20 manifold and a T3 adapter plate, I can get it done for $500-600. And a much simpler exhaust setup.

Yes, I may have to make repairs in the future, or buy a backup manifold. At just over $200, not a big deal. If I were approaching this for ultimate power, I would go the LCE route. But my main focus is some power, more economy. And idea I am not 100% the turbo will help with. So spending over $2000 to get better fuel economy is just not a good bet. At $500, I can drop another turbo on it if I need to play with sizing.

My don't ask don't tell "hair and nails" budget is $600. Anyone married knows what I am talking about.

But for sure it is going to be a t3 or t3/t4 mounted up to it. The CT20 turbo gives me no sizing options. And that is going to be the most critical part to get right!

 

It seems to me you have a good understanding of turbo's and tuning (i have not done much of either). I say go for it. It would be most cost effective to make friends with a welder. In the mean time your best bet is ebay manifold and make up a strong brace to support it. I fell like most cracked manifolds are either from heat build up (poor oem design manifold) or to much weight and vibration hanging off of the manifold. Good luck and keep us posted on how it turns out.

 

Lol I have a pretty decent welder, but it needs to go in for service. It has an issue with the main controller board. I am not great at welding though...

Yeah, I have done a few installs over the years... Learned a few big things. First how OEM systems are setup and mounted are frequently are the best to copy for longevity, but not always. Turbo heat cycling loosens everything it touches. Use studs and nuts wherever possible, not bolts. Especially mount the turbo to manifold with studs and nuts. When you move away from factory install components like manifolds and downpipes, copy if you can. When you move to fully custom setups, BRACING BRAING BRACING!

Good bracing and a downpipes that gives, will make the difference between a system you are fixing every oil change, and one that stays together without issues. For my downpipes I use v-bands wherever I can. They take a lot of stress out of getting it all perfectly aligned. My last setup, I could pull the turbo out in 15 minutes. And it was behind the engine on a traverse mounted driveline.

Jimkola was right, I am currently unhappy with the power output on this beast. But then I haven't put a lot of miles on this to know what my baseline actually is. Monday's shakedown drive was the first time I tried to get it above 40mph, it failed. I simply know the reports of power and fuel economy that I have gotten. And I realized mine seemed a lot worse than these after that drive. A few checks, and sure enough I have some issues to sort out. Mostly, my timing was WAY OFF. Somehow, this 22RE engine still ran smooth as butter. I am having trouble getting the timing to "lock", or maybe just having a problem with the TPS.

Anyways my point is, get your foundation in order before building a deck on it lol. A big goal of this project has always been a cheap recipe other Toy RV owners could potentially follow for more economy and power. To make this realistic for a non-gear head type to follow, I need to retain the factory harness and have something that plugs right in. Currently, I have a code 11 coming up indicating a problem either with my harness or the TPS sensor. So I am trying to sort that out before proceeding.

Honestly, it would be much easier for me to just gut the engine harness and build a new custom one. I could be running by the end of the weekend on the 'squirt.

 

I’ve written a few times how to dial in the TPS using a timing light. I highly recommend that over trying to use a multi meter and the FSM.
if you can’t lock it in with that method than possibly there’s a issue with the TPS.

 

Jim do you have a writeup or a link to a post about that? This is EXACTLY what I need to know!!!

I was just about to post an update on my 22RE ignition module thread. Turns out one of my good friends, happens to be (unknown to me) a Toyota geek/expert with a weakness for the 22RE! I spent about an hour on the phone with him tonight and he pointed me on the right track at least. And everything seems to point towards the TPS being either improperly adjusted, or bad.

 

tps adjustment

My career with Toyota started when the 20R/22R# engine was in a majority of vehicles being sold or serviced. Consequently, I've seen more than my fair share of aftermarket components designed to increase that engine's power, torque, fuel economy, speed, or whatever. In all honesty, most had nominal, if any, real performance gain. And it was always a trade off. So feel free to experiment, and have fun while doing it. I just caution people before dumping thousands in a 22R# project with a questionable outcome, keeping in mind that most of this was tried years and years ago. Now throw on the weight and aerodynamics of a RV and you can see my skepticism.

 

Thank you for that Jim! I need to get the baseline perfect first before continuing.

Simply put the 22RE was probably the best engine of its time (and many think it one of the best Toyota ever made), and with the best EFI system, of its time. But while it used the best technology, it is now over 35yr old technology. I am not putting magnets on the fuel lines or resistors in the IAT/CLT circuits. Or loosening the tension on the AFM vane spring. Or bb's in the FPR line. Yes, been there, done that 30yrs ago. I cut my teeth modding Bosch L-Jetronic. The Nippondenso is basically a smarter L-Jet with early OBD. Normal kids had the latest comic book or a copy of Playboy under their pillow. I had a copy of "Bosch Fuel Injection and Engine Management: How to Understand, Service and Modify", "Performance Tuning the Fiat/Lancia Twin Cam" and a few other such classics under mine. And I devoured them.

But that technology is actually 40+years old if you take into account the L-Jetronic was out in 1979-1980. So a MUCH FASTER modern computer, running modern better atomizing fuel injectors, running slightly higher fuel pressure, with upgraded ignition control, and much more precise wideband oxygen sensors capable of lean burn tuning, so all this isn't going to make a difference?

I agree that an average user/installer probably would only see moderate gains without a lot of time/help. I have done well over 200 installs (this is the number of old customer folders I happen to still have, who knows how many I have lost). Tuned and fixed those, and plenty more. I have been doing this long enough, the technology available has actually passed me by!

Anyways if you look at the old Toyota engine management, it is VERY outdated. And easily improved upon with a newer more modern system and somebody who actually has a clue how to tune them. I mean just removing the AFM will make a big difference in how crisp the engine revs, and add in some MPG too. I have converted plenty of Digifant, L-Jetronic, and Nippondenso systems in the past and they always felt like completely different engines after.

I a not making any crazy claims. There are plenty of reports on the Toyotamotorhomes forums of 13-16mpg with more than a a few claiming to have hit as high as 22mpg. Even if you toss out 75% of those outliers, there are enough left over to realize that the engine and platform are capable of sustaining 20mpg with the right tools.

Yes, it would cost somebody thousands and thousands of dollars to attempt this if they paid a reputable tuner/shop to do it. Parts alone could hit $2-3k. But I have everything needed collecting dust on my shelves. Actual money spent on this EFI conversion so far? $7 for an IAT sense and pigtail as I didn't remember where my pigtails were. $40 on a corolla distributer, just to look at the pickups inside it. $50 for 8 high flow/high z multi-hole injectors and plugs. And more than I want to admit to for the Perfect Tuning gauge that's cool, but probably unnecessary. I paid less than retail, still... If/when I go turbo, those parts will worse case add on $1k. Rear end ratio swap, maybe $150.

 

Jimkola to the rescue! Thank you again that worked perfectly! Since I suspected the TPS was incorrectly adjusted, I started there with unbolting the TB and rotated the TPS, and bolted it back on. Left the bottom screw loose. Tightened the top. I was able to get it perfectly dialed and can see it go in/out of lock now when in lock mode and the throttle bumped off the rest position.

I didn’t recheck to see if it cleared the code 11. Is it cleared automatically, or is there something I need to do further to clear it?