Best turbo/ turbo specs for turboed 5l? (1 Viewer)

[advlars]

Hey all.

It seems like most people who turbo their 5l just use the ct20 manifold and ct20 off an old 2lt. This seems inadequate for a 5l, as it seems pretty stuffed up on the smaller motor already. In any case, my ct20 is garbage. There are manifolds available for t25/t28 turbos, but I cant for the life of me figure out what size inlet, outlet, trim and a/r I should be looking for. Can anyone give me a ballpark size I should be looking at? My goals would be very conservative boost levels (5-7psi maybe) and keeping the egts as low as possible.

Of course Im still not sure about going turbo on the 5l, but Im trying to gather as much info as i can about it.

 

[Locked79]

@5-7 psi, its not even worth putting a turbo on. 12-15psi and set the fuel conservatively. At 5 psi, you can't even wind more fuel into it. Aim for 22:1 afr at full load.

Sorry, can't help you on turbo sizing.

 

[advlars]

Well, 5-7 seemed like a good starting point with the option of pushing on up from there if things look good. If Im able to bring the compression ratio down a bit with a thicker headgasket and confirm that the 5l has reinforced pistons and oil squirters etc im open to higher boost in the future. My point is really just that i want a driveable and reliable truck, and Im not looking for a race car.

I still have no idea where to start with selecting the turbo though. There are so many factors (inlet size, outlet size, trim, a/r) and they all seem to affect each other.

 

[GTSSportCoupe]

If you're looking for a good 'junk yard' turbo, look for a low km Mitsubishi TD04L-13T from a Subaru WRX. Many Subaru owners upgrade, so there are quite a few of these on the market. This particular turbo works well on a 3B diesel which is 3.4l displacement. The 5L is very similar in displacement, and might even flow a little better, so it would probably work well. There are flanges/gaskets available for this turbo on ebay and kinugawa. If you want hardcore turbo info ask @gerg or @Dougal .

02-05' SUBARU FORESTER IMPREZA WRX 2.0L TD04L-13T *USED | eBay

 

[advlars]

Hmm, that looks like an option. And theres a pretty good range of used and remanufactured ones on ebay for slightly better prices than the garretts ive found.

Kinugawa even has some td04l-13ts built onto a t25 body. Im still struggling to find a really good spec listing for them but I guess they must be pretty comparable?

 

[dare]

As GTS says, the TD04l-13t would be pretty good, might be a little on the large side? I'll map it out for you tonight, gotta go to work now. The Kinugawa ones are just a T25 exhaust manifold flange, they share nothing else with a T25. The TD04l-13t is more modern than a T25.

CT12b from a 1KZ (3.0l) would be a good choice but it would need a manifold adapter.

Mitsubishi 4m40 (2.8L) runs a TD04-12t which are dirt cheap on eBay. Would also need a manifold adapter but there are T25 housings for them.

Baby T25 (52mm compressor, 0.49 a/r exhaust) off a CA18 or RD28. I don't know how common these are over there but they're practically worthless here second hand.

GT2052 is a more modern Garret alternative to the T25.

FWIW I'd use the 2L-T manifold with an adapter, aside from a slightly cleaner install I don't see any reason to spend the extra on an aftermarket manifold.

 

[advlars]

Right on! This is a whole bunch of good options to consider.

Are you saying the baby t25s are worthless because they are no good? or just a dime a dozen?

and would the gt2025 be optimal in the same spec as the t25 listed above?

And I fully agree the 2lt manifold would be the best option. But my manifold is a 2lt-i not a 2lt-ii or 2lte so adapting that might be difficult. Maybe when my parts show up I can see if theres a good way to make it work. Of course, If anyone has a spare manifold, Im interested!

 

[cruisedeisel]

You got a welder and a grinder/zip cut? Its super fun fabricating up your own. Then you can make any flange for any turbo out there. 2x asking gerg. You have to modify the injection pump for a boost compensator too, as it will only have an altitude compensator.

 

[advlars]

Yeah, I do have a welder and that is an option. It's kind of a s*** welder though. There's also a hacker-space co-op shop in town with a mill and laser cutter etc i could use for super cheap. If my gasket shows up before my Engine I could use it as a template to get started.

To be fair a legit tubular manifold would probably be way better than the cast log style crap that Toyota and the aftermarket brands make.

 

[Mcreight911]

Id stay away from the gt25 garrets the turbines housings arnt suited . The td04 13t 6cm or holset he211 5cm for a fast spooler or tdo4hl 16t or holset he221 5.5/6cm for a bit more top end. The tdo4 16t is a faster spooling more efficent turbo than the ct12b . The tfo35 12t 4cm from a later model Pajero are pretty small and you'll have drive pressure issues above 12psi. The holsets are both t25 flange or you could try the 3 bolt Volvo tdo4 6cm turbine it has a v band outlet and a bit better designed wastegate similar to the new Borg Warner efr series turbos .

I'll Tri to get the dyno from my turbo builder of the 5le they did recently . They ran the td04hl 16t at 12psi, customer fitted the intercooler and turbo and made 30rwhp 30:1 afr's pre tune, after tune made 120rwhp @21:1

 

[advlars]

Just to clarify @Mcreight911, was that supposed to say 130 rwhp? or did he really only make 30 at first? Anyway, getting 12rwhp to the wheels seems pretty impressive for these trucks

Anyway, a bunch of you have recommended the td04, but everybody has listed a different t number (12t, 13t, and 16t) How much difference am I really going to expect from this range of compressor wheels? Td04-14t seem to be the most available and look like theyve got an easy flange to work with

 

[Mcreight911]

Just to clarify @Mcreight911, was that supposed to say 130 rwhp? or did he really only make 30 at first? Anyway, getting 12rwhp to the wheels seems pretty impressive for these trucks

Anyway, a bunch of you have recommended the td04, but everybody has listed a different t number (12t, 13t, and 16t) How much difference am I really going to expect from this range of compressor wheels? Td04-14t seem to be the most available and look like theyve got an easy flange to work with

Yep 30rwhp with turbo and intercooler
But no tune . Lack of fuel , I'm not sure if there were other issues but of the 5le's that iv seen go 45-50rwhp standard

The 13t compressor is a very efficient little wheel . But can't flow the Lb/min that the 16t will. So if your trying to keep the boost low than you'll need more volume to match the fuel needed to make power . Comes down how much power you want really and where you want the power . Dougal or Gerg would be able to calc the difference in airflow between the 2 for a given psi and work potential power from there .

 

[gerg]

What is your rpm range. I mean reality and not race applications. Do you guys rev above 4K often?

 

[advlars]

Hard to say as my trucks got no tach, but its a low revving engine. Most of the L-series engines list peak HP between 4000-4200 rpm but I dont think I operate in that range very often. Maybe when Im pulling steep grades, but I try to avoid it. Maybe somebody else with an L-series has an aftermarket tach? @GTSSportCoupe?

The 13t compressor is a very efficient little wheel . But can't flow the Lb/min that the 16t will. So if your trying to keep the boost low than you'll need more volume to match the fuel needed to make power . Comes down how much power you want really and where you want the power . Dougal or Gerg would be able to calc the difference in airflow between the 2 for a given psi and work potential power from there .

So youre suggesting a bigger wheel for low boost applications? or the other way around? Doesn't more volume= more pressure at a given rpm?

 

[Mcreight911]

yes bigger wheel for low boost. 12 psi on a 13t is quite a bit less lb/min of air pumped than 12psi on a 16t . Engine ve will effect things to . As well as exhaust backpreasure . I don't think you would spend much time above 3500rpm

It's about maximising the lb/min of air pumped in your desired rev range giving you the option to add the most amount of fuel possible and maximise the power posential .

If it were myn I'd be looking to maximise the 1500-3500 rpm range . But I'm greedy and would run 20psi minimum .

How do you typically drive ? Rev out each gear or change at low revs and lug it around . Do you carry any weight or tow often ? Will it be intercooled . Just trying to get an idea wich option will suit your application best

 

[gerg]

So it looks like the 13t maxes out flow around 3400-3500rpm at 20lbs boost and the 16t can hold on barely till 4500 at 20lbs.

So at first glance the 16t looks like a no brainer, but at 20lbs boost at 2000rpm its getting very close to surge. At altitude and on a hot summer day that could be dangerous. So now that being said, getting a little engine like that to create boost on an HL sized turbine is no small feat. I think it is unlikely.
g

 

[gerg]

Don't forget about the 19t as it has significant surge resistance and maps better than the 16t

 

[Mcreight911]

The 1kz's are doing 18-20psi by 2000rpm both with the electronic and manual pumps . The 5le was a surprise for the tuner as is responded better than the 1kz at 12psi

At 12psi on the HL wheel I couldn't see surge being an issue

 

[advlars]

Hmmm... ok. Well what happens with those turbos performance if Im looking to do like 10lbs of boost? I think 20lbs is way outside what Im comfortable running in this engine, unless I do A LOT of serious work in the engine. There are a lot of guys who have suggested on other threads that I not even consider turbo-ing the 5l given the high compression ratio and the L-series propensity to head problems (cracking, precups, etc.). It seems to me they bring up some very valid points and at the moment Im having a ton of trouble finding the internal parts I would need for serious boost (oversized head gasket, fresh precups etc) so the deep engine work may not be feasible for a while.

Yes, it will be intercooled, and yes it will be loaded down regularly. The truck has a big overland camper on the back and lots of gear. Usually I keep it slow and low unless Im trying to climb a grade or get onto the fwy.

 

[gerg]

So there is always a lot of talk about turbos and cracking pre cups. Hot shutdowns are a lot harder on precups and you don't need a turbo to not idle your engine and cool it off before shutdown. High compression ratios and turbos are not a great combo. Intercooling lowers intake air temp and help keep the timing from thermally advancing. It still does do that a bit though. I did alot of head work and ended up removing a fair bit of material from around my exhaust valves and some from the precups which lowered my compression a bit. I also retard my timing on my 3B to lower peak cylinder pressures. This surprisingly makes the engine somewhat more fun to drive as you shift peak torque down in the RPM range. Cold starts require more glow plugs.