Turbo question....

[4RunnerChaos]

So I have a question for anyone out there who has experience with turbos

I've seen in a few pictures where guys run a twin turbo setup where the down pipe runs right into the compressor housing of another turbo... I like the idea of this but I'm not sure how that would effect the spooling of the second turbo.... Or if the run a smaller turbo for the second so they both spool up and produce the same amount of boost at the same time.
Or B run a larger turbo as the second turbo that will start to spool and be able to keep the boost in the higher rpm range when the smaller turbo can't keep up...?
I feel like either way would work.

If the latter of the two options would work, I was thinking of attempting something like that, rear mount where the cat currently is using a GT25 turbo in front of a larger turbo to prevent the turbo lag. The gt25 would start building boost almost as soon as you start on the throttle and once it hits the say.. 10 psi the wastegate would open up relieving the pressure on the small turbo and continue operating the larger turbo.? I understand this would take a lot of engineering and dyno time to keep from blowing up a turbo (or worse yet an engine)

Any thoughts ideas links pictures or personal experience would be greatly appreciated. But please don't do the "my buddy's cousins friends uncle ran eight sequential turbos on his 350 sbc ran over 60 psi of boost and made 3000 hp" comments. Thanks

 

[RockenAlex]

I have little experience with gas turbo's, but on diesel engines they call the setup "compound turbos" and that's what your describing with the small and large turbo setup. scale it down a bit for a gas V6 by that's what I believe your aiming at here. Google that because there's lots on info from coal rollers out there.

Good luck!

 

[snow junky]

you trying to build a 1000hp 4runner?

a single 57 trim will have more then enough airflow to blow a 3.4l

if your that worried about lag add a little no2 or supercharger

 

[AZ4Running]

I have a bit of turbo experience. You are best off with a single turbo matched to your motor and power goals. Remember KISS, stick with what is tried and true. A Garret T3 60-1 .63ar, T3T4 60 trim .63ar or a Holset 30hx off a 5.9 cummings will all be good turbo choices for the stock 3.4l looking to make 300-400whp. Of coarse you can go with less boost and make less power on the same turbos with no issue and it wont be laggy, thise turbos should do well for 250-400whp on the 3.4l. You would need to have all the supporting mods for a turbo like intercooler, wastegate, bov, larger injectors, larger fuel pump and tuning. Unichip i think is the only tunning system for our 4runners but you may be able to make other piggyback tuners work. You will need to have a custom exhaust made to feed exhaust to the turbo. Do a search for turbo 4runners and see what you find.

 

[MTD]

[MENTION=9139]steezemcqueen[/MENTION]

 

[e46inperrycounty]

You'll also want to look into low compression forged pistons and some good rods, ARP headstuds and a good head gasket, as well as rising rate fuel pressure regulator, and possibly adjustable cam gears and/or a set of cams. Then you'll continue to find the next weak link until you either have a bulletproof engine and drive line, or you get mad and set it on fire and push it off a cliff, whichever comes first....lol

 

[slides]

You'll also want to look into low compression forged pistons and some good rods, ARP headstuds and a good head gasket, as well as rising rate fuel pressure regulator, and possibly adjustable cam gears and/or a set of cams. Then you'll continue to find the next weak link until you either have a bulletproof engine and drive line, or you get mad and set it on fire and push it off a cliff, whichever comes first....lol

how much power can the motor take stock. I know my bmw could take 500whp but how good are these 4runners. just gone mine a few weeks ago and also interested in a turbo

 

[snow junky]

your better off puting a ls1 in and twin turboing that if you all want a race truck

 

[Robb235]

So I have a question for anyone out there who has experience with turbos

I've seen in a few pictures where guys run a twin turbo setup where the down pipe runs right into the compressor housing of another turbo... I like the idea of this but I'm not sure how that would effect the spooling of the second turbo.... Or if the run a smaller turbo for the second so they both spool up and produce the same amount of boost at the same time.
Or B run a larger turbo as the second turbo that will start to spool and be able to keep the boost in the higher rpm range when the smaller turbo can't keep up...?
I feel like either way would work.

If the latter of the two options would work, I was thinking of attempting something like that, rear mount where the cat currently is using a GT25 turbo in front of a larger turbo to prevent the turbo lag. The gt25 would start building boost almost as soon as you start on the throttle and once it hits the say.. 10 psi the wastegate would open up relieving the pressure on the small turbo and continue operating the larger turbo.? I understand this would take a lot of engineering and dyno time to keep from blowing up a turbo (or worse yet an engine)

Any thoughts ideas links pictures or personal experience would be greatly appreciated. But please don't do the "my buddy's cousins friends uncle ran eight sequential turbos on his 350 sbc ran over 60 psi of boost and made 3000 hp" comments. Thanks

I personally think the setup you describe would be a disaster on many levels. First thing that comes to mind is that it would be a logistical nightmare finding locations to mount the turbos, so many oil feed and return lines, scavenge pumps for both turbos, etc. Also, once your first turbo spools up and the second one takes over, that first turbo is still a restriction in the exhaust flow and will choke the engine.

I don't think there would be a whole lot of benefit to running that kind of setup versus the extraordinary effort you would have to put into such a project. Stick with one turbo.

 

[e46inperrycounty]

Most decent motors can safely run ~7psi of boost. But as with anything, you are taking away reliability and longevity away the more you try to get out of it power wise. I've seen as much as 14psi run on a bone stock motor, it lasted about 7k miles. That was just piggy backed with a wide band O2 to try and keep a/f in check. Stock injectors, stock fuel pump, and that was a b series Honda motor. I know guys running 8psi daily and have been for years on stock motors . Would I do it myself? Nope... I'd build it for boost, or swap it to something else.

 

[e46inperrycounty]

I personally think the setup you describe would be a disaster on many levels. First thing that comes to mind is that it would be a logistical nightmare finding locations to mount the turbos, so many oil feed and return lines, scavenge pumps for both turbos, etc. Also, once your first turbo spools up and the second one takes over, that first turbo is still a restriction in the exhaust flow and will choke the engine.

I don't think there would be a whole lot of benefit to running that kind of setup versus the extraordinary effort you would have to put into such a project. Stick with one turbo.

I believe he was referring to a compound twin setup where the exhaust passes through both hot sides and the pressure side of the small turbo pressurizes the inlet side of the second larger turbo helping it to spool up. There are also ways to run a bypass flapper valve like the BMW 1 series twin setups or the twin boxer setups in JDM wrx's. They are insanely hard to tune and find the sweet spot and compressor housings are a nightmare to match up. I've always preferred a big single turbo to any type of twin setup personally, though the goals of the build are different for a lot of people.

 

[e46inperrycounty]

In addition, if it were me, I would just get the TRD supercharger kit that was designed for the 3.4 and call it a day. If it didn't void factory warranty then I'd imagine it is safe for daily driving and the addition of 75hp 77ft/lbs is probably better than you could expect from a daily turbo setup and you wouldn't have lag to deal with. Turbo is like a 2 stroke, it takes a second to get into the power band and once you are there its great, superchargers are like a big block v8, its there from the time you thump it to the floor until you let off it. Both have their place, both are awesome, and both have their short comings. Figure out a budget, performance goals, and the kind of longevity and reliability you want. Remember, cheap-powerful-reliable, you can only pick 2 of them...

 

[4RunnerChaos]

I believe he was referring to a compound twin setup where the exhaust passes through both hot sides and the pressure side of the small turbo pressurizes the inlet side of the second larger turbo helping it to spool up. There are also ways to run a bypass flapper valve like the BMW 1 series twin setups or the twin boxer setups in JDM wrx's. They are insanely hard to tune and find the sweet spot and compressor housings are a nightmare to match up. I've always preferred a big single turbo to any type of twin setup personally, though the goals of the build are different for a lot of people.

To everyone saying "just get a supercharger" $3000 is out of budget.

I understand where you're coming from with the restriction of of the smaller turbo, I would look at doing a wastegate as close to the size of the exhaust pipe and dump into the exhaust pipe after the first turbo and before the second turbo to prevent the restriction of the first.
Maybe run an electronic cutout the diverts exhaust flow around the turbo once it hits around 7 psi and wont close until going under say... 0 psi so it won't say flutter when it does that and take a slight drop in boost when it initially opens up. Just a way of looking at things in a different way.

And no I'm not looking to make a 1000 hp 4runner. Just trying to get the boost as soon as possible. Looking at the price of two turbos $400 two sets of oil lines $200 two oil sumps $200 flanges and hardware $100-150 4" stainless exhaust pipes $80.
$1100... Vs $3000?


What's better about turbos than supercharger? 100% of power made is used instead of the ~70% from a supercharger. Disadvantage is it's not easy.

 

[4RunnerChaos]

how much power can the motor take stock. I know my bmw could take 500whp but how good are these 4runners. just gone mine a few weeks ago and also interested in a turbo

Gadget and urd racing have built many turbocharged 5vz engines all the way to fully built 800hp engine which started to damage the cylinder head so they turned down a bit. Properly built 5vz should handle 500hp with proper tune etc.

I'm personally not looking for anything insane. Just trying to get ~300 hp ~400 ft lbs tq. Which would be about 7psi turbocharged.

 

[Robb235]

To everyone saying "just get a supercharger" $3000 is out of budget.



I understand where you're coming from with the restriction of of the smaller turbo, I would look at doing a wastegate as close to the size of the exhaust pipe and dump into the exhaust pipe after the first turbo and before the second turbo to prevent the restriction of the first.

Maybe run an electronic cutout the diverts exhaust flow around the turbo once it hits around 7 psi and wont close until going under say... 0 psi so it won't say flutter when it does that and take a slight drop in boost when it initially opens up. Just a way of looking at things in a different way.



And no I'm not looking to make a 1000 hp 4runner. Just trying to get the boost as soon as possible. Looking at the price of two turbos $400 two sets of oil lines $200 two oil sumps $200 flanges and hardware $100-150 4" stainless exhaust pipes $80.

$1100... Vs $3000?

$3000 would be the price a brand new SC, yet your $1100 cost appears to be made up of unrealistic numbers, no offense. As someone who is actively in progress (slowly) piecing together a turbo kit, I can tell you that there are a LOT of incidental or "ankle biter" costs that you're not thinking about, especially due to the complexity of your proposed setup. $80 to rework your exhaust into the complex manner you describe? No way. And where is the cost of your wastegate(s)? $200 for both your turbo scavenge pumps? You must be using super cheap pumps that will leak after a year. $400 for two turbos? What are you using? For that price you're getting something bottom of the barrel from the used market, or extremely cheap Chinese turbos that explode after 1,000 miles. Where's the cost of your custom intake and the silicone clamps? Boost gauge? All the different gaskets you'll need? Modified oil pan? And believe me, you will make several trips getting parts and tools that you never counted on. For a cheap single turbo rear mount (like Clownmeat's), $1100 is on the low end. For the multi-turbo, complex setup you describe, you'll easily surpass your $1100 number, and probably the $3000 for the SC as we'll.

 

[e46inperrycounty]

If you can build a twin setup for 1100 then go for it, I couldn't build a decent single setup for that. Electric cutouts are expensive, controlling one through something that will switch one at 7psi should be interesting as well. Not to dash your dreams, but for that torque goal, you are looking at something more in the 3-5k cost for the build. 7psi won't get you there, 16psi will be closer but still fall short I believe.

 

[AZ4Running]

Dude if a $3000 supercharger is over budget then doing a custom turbo setup in your 4runner is a pipe dream. Expect to spend at least that on doing turbo.
As for can the motor take it, if it is a good strong motor yes. I would think 100-150 more hp is doable with the 3.4l. Boost is boost it does not matter if its turbo or supercharger boost. As long as you do it right ie larger injectors, fuel pump and good tuning the motor will last 200k miles plus on boost. Oh and you dont need to lower compression and build the motor with all forged internals you are not building a 500whp+ 4runner. Stock motor will do fine for mild boost and power levels and the stock compression is fine. I have civic with a b series vtec swap 10.6:1 compression all stock internals that i will be turboing and planning for 280-300whp.

 

[4RunnerChaos]

If you can build a twin setup for 1100 then go for it, I couldn't build a decent single setup for that. Electric cutouts are expensive, controlling one through something that will switch one at 7psi should be interesting as well. Not to dash your dreams, but for that torque goal, you are looking at something more in the 3-5k cost for the build. 7psi won't get you there, 16psi will be closer but still fall short I believe.

Don't worry you can't dash my dreams only make me more determined lol. And if done properly reaching boost sooner will improve tq much more than hp. Which is what I was aiming for. Not trying to pull any 11 second quarters or anything. Just for more drivability.

Here's a link to a picture of exactly how I was thinking and would like the setup to work http://ls1tech.com/forums/attachmen...ial-twin-turbo-idea-open_sequentiel_small.jpg

And as for parts, I have a source in Japan that is willing to make trips to a used aftermarket parts shop called "upgarage" I just look on the site and order to the store near him he picks it up and sends it to me. A pair of Garrett gt25 turbochargers with internal wastegates for $125+ shipping.
Plenty of name brand aftermarket parts for dirt cheap prices.. Access to a mandrel pipe bender and cheap steel pipe and my neighbor welds for dirt cheap and I can cut grind and get fitmwnt of everything myself. Full access to a shop with a vehicle lift. Already have a boost gauge. Oil line kits are $30 each shipped, oil catch tanks (used oil pan from a junk yard for $5 with a steel plate bolted to the top using a new gasket) two oil return bungs to fit into oil pan $15 drilled holes filed to fit myself and welded in by my neighbor. Oil sump $90 shipped if it leaks after a year ill buy another one for $90.. How long does a $300 oil sump last anyways? 3... 4 years? If that's the case there really isn't much difference.
There's many ways to look at things. Stop looking at the cup half empty Rob. Be a constructive individual not a destructive individual. I know I may be dreaming by on this but what's life without dreams? Where would we be if people didn't come up with things people thought were completely rediculous. Nowhere. Anyways thanks all for the replies. I'm still gonna look at all this stuff. Research how the ford ecoboost twin turbo setup is done

 

[4RunnerChaos]

you trying to build a 1000hp 4runner?

a single 57 trim will have more then enough airflow to blow a 3.4l

if your that worried about lag add a little no2 or supercharger

At what rpm do you start building boost with that .57?
And what are the Other specs on the turbo

 

[Robb235]

Don't worry you can't dash my dreams only make me more determined lol. And if done properly reaching boost sooner will improve tq much more than hp. Which is what I was aiming for. Not trying to pull any 11 second quarters or anything. Just for more drivability.

Here's a link to a picture of exactly how I was thinking and would like the setup to work http://ls1tech.com/forums/attachmen...ial-twin-turbo-idea-open_sequentiel_small.jpg

And as for parts, I have a source in Japan that is willing to make trips to a used aftermarket parts shop called "upgarage" I just look on the site and order to the store near him he picks it up and sends it to me. A pair of Garrett gt25 turbochargers with internal wastegates for $125+ shipping.
Plenty of name brand aftermarket parts for dirt cheap prices.. Access to a mandrel pipe bender and cheap steel pipe and my neighbor welds for dirt cheap and I can cut grind and get fitmwnt of everything myself. Full access to a shop with a vehicle lift. Already have a boost gauge. Oil line kits are $30 each shipped, oil catch tanks (used oil pan from a junk yard for $5 with a steel plate bolted to the top using a new gasket) two oil return bungs to fit into oil pan $15 drilled holes filed to fit myself and welded in by my neighbor. Oil sump $90 shipped if it leaks after a year ill buy another one for $90.. How long does a $300 oil sump last anyways? 3... 4 years? If that's the case there really isn't much difference.
There's many ways to look at things. Stop looking at the cup half empty Rob. Be a constructive individual not a destructive individual. I know I may be dreaming by on this but what's life without dreams? Where would we be if people didn't come up with things people thought were completely rediculous. Nowhere. Anyways thanks all for the replies. I'm still gonna look at all this stuff. Research how the ford ecoboost twin turbo setup is done

My first question is what does the Ford Ecoboost have anything to do with this discussion? Last I checked, Ecoboost is not rear mount, not compound boosted, and is not multi turbo? Not sure where you were going with this?

I'm not trying to piss all over your parade, but it's pretty clear that you're stuck in the "theorizing and dreaming" stage, and haven't looked at all at how practical it would be to implement any of this. Have you even looked under your truck? You would have so much piping on your hot side and cold side you'd literally be dragging that sh!t on the ground as you drove down the road. I'm currently in the process of building a budget front mount turbo with mainly used parts, and I'm well over the $1,100 mark ($300 turbo, $300 44mm wastegate, $600 manifolds + downpipe, and nickel and dimed to death and all the different gaskets, adapters, pipes, clamps, etc.). And here you are with multiple pumps, turbos, TONS of piping, electric cutouts, etc. there's no way you'd be under the $1,100 mark, even if you do have some secret squirrel connection in Japan somewhere.

And what is even the benefit of all this? Unless your running some super high PSI, the benefit will be next to nothing over a single turbo setup. At low boost you should be within the compressor's efficiency range on a properly sized turbo; lag should be very minimal and will provide the power you want in the higher RPMs.

Again, not trying to sh!t all over your parade, I love reading about other people's turbo projects, but I think you need a bit of a reality check. If you're able to even pull this off, let alone under your $1,100 benchmark, I will personally buy a plane ticket the next day and fly out to where ever you are and marvel at your setup.

Is this your first turbo project?