Turboing the 4AGE (rough draft)

[saifmansour]

I would like to thank you again for your help . As soon as I start my project I will give you my feed back , thank you ..

[saifmansour]

Can I keep the head gasket stock ?

[yoshimitsuspeed]

Can I keep the head gasket stock ?

People have good luck with the stock headgasket. There are also a number of high quality aftermarket options.
If you go OEM make sure it's the later one for the GZE. I think that part replaced the older one but I'd just make sure.

[Straitup D]

what about the AFM? do i run the flappy door or convert to map? i have a 4age 7 rib with GZE pistons and a smallport head and blue top cams,, running a T25 from an S13

[yoshimitsuspeed]

what about the AFM? do i run the flappy door or convert to map? i have a 4age 7 rib with GZE pistons and a smallport head and blue top cams,, running a T25 from an S13

As long as you are on the stock AFM ECU you will need to keep the AFM. Once you go aftermarket engine management it's up to you. Most people prefer to go MAP at that point.

[Straitup D]

Awesome!! I looked around for a little bit, and forgive my ignorance, but is there a wright up on what map sensor to use?

[yoshimitsuspeed]

Awesome!! I looked around for a little bit, and forgive my ignorance, but is there a wright up on what map sensor to use?

That really depends on your goals. Aftermarket engine management can be programmed to receive most sensors so you just want to pick one with the range that you plan on using.
https://www.diyautotune.com has most everything you could need for this. I can also get you parts through them so If you go through me I sure appreciate it. That way I can make a couple bucks for my time

I can also get most any other parts you could need for a turbo build. I can get stuff from Garrett, Greddy, Frozenboost, CXracing and just about anything else you could need.

[Straitup D]

ok, yet agin sorry for my ignorance, so T25 Stock ECU Stock injectors i can run 7PSI (wastgate pressure) i can do this and not have any issues? at what point will i need say an SAFC or bigger injectors for that matter

my goal is say 175WHP

[yoshimitsuspeed]

You may need bigger injectors or other mild fuel tweaks before 7 PSI.
If you are going to try to boost on the stock NA ECU you will want to do something like this.
I always recommend if possible getting a wideband gauge before boosting it to get used to how the stock system runs. If you have already installed your turbo you can even run with the wastegate disconnected just to see how the system responds.
From there I would recommend starting at about 5 PSI boost. See how this effects the AFRs. You might notice it starting to get a little lean but should be safe while you try to dial it in. From there you can play with fuel pressure or bigger injectors. An adjustable FPR would probably be a good place to start because you can tweak things up or down as you need. Between that and AFM tweaks you should be able to get safely between 6-8 PSI.

[Straitup D]

awesome! what would you segest for an injector and a FPR?
also i have a 255 pump all ready installed

[yoshimitsuspeed]

awesome! what would you segest for an injector and a FPR?
also i have a 255 pump all ready installed

There is an FPR kit that I can get pretty cheap that allows you to modify your stock FPR into an AFPR. Unfortunately the 255 tends to overwhelm the stock FPR so I would highly recommend going to an aftermarket unit.

I can get a number of quality FPRs including Turbosmart, Aeromotve, and a number of others.
I would start there and worry about injectors as a next step if you need it.

[Straitup D]

Dose any one run dsm blue top 450cc injectors?

[yoshimitsuspeed]

You really need to specify if you are talking about the stock ECU or not. If you are on aftermarket engine management then yeah they will work fine as will 3SGTE 440s and many others.
If you are on the NA ECU then no way. If you are on a GZE ECU then they can sorta be made to work with lots of work but it's still really outside the scope of what it can handle well.

[nevomr2]

I thought 3sgte injectors were side feed...anyways, the 4ag uses top feed injectors.

[yoshimitsuspeed]

Later 3SGTE run side feed. I forget where the cut off is but at least gen 1 and gen 2 run top feed. SW20 3SGTE injectors are definitely top feed.

[daveskatesallday]

Later 3SGTE run side feed. I forget where the cut off is but at least gen 1 and gen 2 run top feed. SW20 3SGTE injectors are definitely top feed.

pm sent yoshi

[Straitup D]

these are the later DSM injectors

[jondee86]

Sticking this in here as it is kind of relevant. If the OP would prefer this to be in
a separate thread, just say so, and I will shift it.

I have been considering a few alternatives to get a bit more torque from my
smallport N/A 4AGE, and got to wondering about these CX Racing T3 Top Mount kits...







What started me thinking was my DD which is a Mitsi Colt Ralliart 1500cc with a
tiny turbo and CVT. The combination of the turbo and the CVT makes the car drive
like it had a 2500cc engine. Spools up real early and of course runs out of puff
before redline, but a ton of fun to drive

Now I have a 3-rib bigport engine sitting in the back of the shed, plus a fully
worked bigport head, some 260 deg cams and a set of GZE injectors. The car
already has an aftermarket ECU and a WBO2 sensor hooked up. I'm not looking
for any big power numbers, just a nice boost in torque that comes in early and
hangs on to 6500-7000 rpm.

The CX kit comes with an 8 psi wastegate, so it seems that it could be a good
match for what I have in mind. So the question is... has anyone used one of these
kits ? And if you have, what did you think of it ? Looking at the pics, the manifold
seems quite sturdy, and and the other components look like they would be OK for
an 8 psi build on standard bigport internals. HIT ME

Cheers... jondee86

[yoshimitsuspeed]

For the goals you describe I think the T3 kit will be way too big and you will likely find yourself unhappy with the setup.

I have never taken the time to get familiar with the t3/t4 turbos and have never liked the way they name and rate their turbos. It makes it very hard to know what you are looking at and what to expect.
Just going off the size and the fact that they claim it will be good for 350 WHP I doubt you will hit full boost until 4000-5000 RPM.

For reference here is a 16G that should be able to 350 WHP.

It's probably around 3800 that it hits 8 PSI.

Personally I would not run a no name turbo. I would rather try to find a healthy used turbo or even better get one rebuilt or get one new. This will add to the cost of your project but it will also be more reliable and sure to work for a long time as long as it's taken care of.

If you did go with a CXracing kit I think you would be much happier with this one.
http://www.cxracing.com/mm5/merchant.mv ... _Code=TOKT
I can't speak for the CXracing version but a similar garrett T25 will hit 8 PSI before 3000 RPM with nearly instant throttle response above 3500.

If you will be happy with less than 250 WHP a T25 would be a great choice. Another great option would be the 13T such as those found in many turbo Subarus. Very similar performance and spool. They use a unique flange though that gives you less options for upgrade and would require a custom mani.

I will be making a top mount mani for a customer in the near future. It will cost about $450 for mild steel but it will be made from 11ga steel and should outlast anything sold by CXracing by a significant amount.
That said I haven't heard much bad press about the CXracing manifolds so it may be a decent option.
Their intercoolers and piping kits are fine for any mid level build and I have even used their piping for manifolds and other welding and fab projects with great results. It's particularly the turbos that make me nervous.

I can get products from CXracing. I can usually only match their prices since I don't get much discount but it does help me out.

[jondee86]

Good stuff !! I did a bit of research and it starts to look like the Garrett GT2554R
might be a good match for what I am after to start with. It also has the ability to
go a bit higher than 8-10psi if I get enthusiastic

One of the reasons I'm not chasing big power is that I want to be able to use the
stock fuel pump. Also, I don't want to start having problems with the gearbox and
diff. This seems to be a common complaint once power starts getting up around the
250hp mark. Down to how you use it I guess. I'll be happy if I can get a decent torque
increase in the 3000-6000rpm range, which is where I do most of my driving.

Got a bit more homework to do first

Cheers... jondee86

[yoshimitsuspeed]

Yes, the 2554 would be a great choice for your power goals.
If you do decide to go with a new name brand turbo let me know. I can get most big names like Turbonetics, Borg Warner, Garrett and I believe some others.

[jondee86]

So, while I am doing a bit of learning up on turbo selection, I'd like
to understand if it is possible to size a turbo to an engine so that it
becomes "self-limiting" at the top end. By this I mean, instead of
relying on boost controllers and blowoff valves to stop runaway
boost at redline, just size the turbo so that it runs out of puff at
some engine speed short of redline.

I have been looking at the GT1548 versus the GT2554, and it seems
that this might be self-limiting on a 1600 engine redlined at 8500rpm ?
Presumably, the smaller turbo spools up earlier, delivers the same
10psi of boost in the midrange, and then can no longer make 10psi as
the revs climb ? The boost (torque) drops, acceleration drops, and it
is time to grab a higher gear. Whereas the larger turbo spools a little
later, and continues to make 10psi all the way to redline ?

Is that how it works

Cheers... jondee86

[yoshimitsuspeed]

People have run turbos like this. It's generally not intentional but more taking a given turbo and pushing it to it's limits. For example the second gen DSM guys pushing the stock T25 until it has no more to give.
This is far from the ideal way to push a turbo.
There is a quite a bit going on to think about and you have to consider the whole system. One of the biggest things restricting a small turbo is the amount of energy it takes to drive the turbo. In it's most simplest terms you can think of this as pre turbine back pressure. The exhaust stream spins the turbine which spins the compressor which feeds more air into the intake.
The only turbo I have tested pre turbine back pressure (PTBP) on is my DSM T25 which is pretty similar in overall performance to the 2554. At just 7 PSI boost at about 4000 RPM my PTBP is about 7 PSI. By redline my turbo hits about 13PSI PTBP. This means the exhaust side pressure is almost double that of the intake (boost) pressure. If I stepped up to a turbo that had about the same PTBP as boost pressure my peak potential HP would be much more because the engine wouldn't be fighting that back pressure to make power. To put it another way I could run less boost and make the same power. Now that is just addressing the turbine side.

One big problem with running a turbo unthrottled like this is that your boost level will not stay at the same level.
It will spool super early and then you will have a massive spike in boost in the mid RPM. Since this is usually where peak torque is made and also where knock is most likely you are concentrating your max boost where you probably want the least. As the RPM increase knock becomes less likely your boost and mass airflow starts to drop. Your overall power potential is decreased while you gain only a very small amount of low end spool.

Turbine based compressors have an ideal range they operate in.
If you haven't yet you should play around on http://www.squirrelpf.com/turbocalc/ a little bit. This only addresses the compressor side of the turbo and doesn't predict spool but does tell you the potential of the compressor. It is quite acculturate if your inputs are.
Here you will see that the 1548 just can't move enough air to make a substantial amount of power in it's efficiency range.
In fact on a drunken saturday night I can't manage to get a 4AGE to fit comfortably on the map. No matter what power level you select most of the curve sits to the right of the choke line.
http://www.turbobygarrett.com/turbobygarrett/choke_line
I think this turbo would have trouble making you much power over stock.

If you knew you would be happy with 200 CHP and knew you would never want anything more you might be able to get away with a 2052-1 but you would already be pushing the turbo to it's limits.
PTBP would be extremely high, compressor efficiency would be extremely low, intake temps would be very high. Basically the whole system would be fighting it's self.
The difference in spool between that and the 2056 would be pretty small while the losses up top would be quite large.
Something like the 2056 should spool very fast and the small gains in the low end you might pick up would be far outweighed by the losses up top.

[jondee86]

Excellent I have been having a look at some of the on-line calculators,
and can see that there are quite a number of parameters that need to be
decided before you get a sensible answer. I shall continue to study

Oh, and I didn't mean to run the turbo without any controls. I would be
looking to have an internal wastegate set at 8-10psi. What I would like
to achieve would be a nice gently rising torque curve like this...



... not one that does nothing until 4000rpm and then shoots up steeply.
Maybe I need an electronic boost controller to achieve that ? If so, I know
that my ECU has a closed loop PWM wastegate controller function built-in.
So then I could go with the larger turbo for lower back pressure, and set
the boost vs rpm to get a nice torque curve ?

Cheers... jondee86

[yoshimitsuspeed]

Excellent I have been having a look at some of the on-line calculators,
and can see that there are quite a number of parameters that need to be
decided before you get a sensible answer. I shall continue to study

Oh, and I didn't mean to run the turbo without any controls. I would be
looking to have an internal wastegate set at 8-10psi. What I would like
to achieve would be a nice gently rising torque curve like this...



... not one that does nothing until 4000rpm and then shoots up steeply.
Maybe I need an electronic boost controller to achieve that ? If so, I know
that my ECU has a closed loop PWM wastegate controller function built-in.
So then I could go with the larger turbo for lower back pressure, and set
the boost vs rpm to get a nice torque curve ?

Cheers... jondee86

Gotcha.
There is nothing fancy about a power curve like that. It just requires a small turbo like the ones we are talking about.
Something like a DSM or nissan T25 would give you what you are looking for or the GT2554 if spool is more important than peak or the 2560 if you are willing to sacrifice just a little spool for a little more peak potential.

Here you can see papojs DSM T25 dyno. I believe the surge you see in rising power at the very beginning of the map is the turbo fully spooling. Although he doesn't have a boost plot I'm willing to bet he has full boost by that 3200 RPM or whatever it is. That is also very close to where DSM T25 spools.
I believe the bigger cams on my BT added a little more lag in the low RPM over my old 16v but the gains in the top end are simply amazing.
http://www.mr2ownersclub.com/mr2records ... ia_148.jpg

I don't have much for good videos but here is a 0-60 on my old 16v. You can see the lag is almost nonexistant. With a good launch with the RPM just a little higher I can have full boost by the time the clutch is out with no slump in RPMs like there was there.

In low to mid RPMs boost comes on smooth and predictable and above 4000 it feels much like an NA. You hit the gas and it just goes.
https://www.youtube.com/watch?v=95IDNLMu28E
And just because I love showing off the difference, that was my old 16v GZE on stock 8.1:1 pistons and 12 PSI.

This is my BT at 11:1 compression and 7 PSI boost.
You can see the RPM seem to climb a little slower till about 4k RPM but after that they just climb faster and faster whereas the GZE runs out of steam and rpms climb slower and slower. Overall the BT is faster at almost half the boost.
https://www.youtube.com/watch?v=vdH6MBVb_6o

[jondee86]

All good. Yusss... what I am trying to emulate is the fat midrange
torque that you get with a large engine, but do it with a small engine
and a turbo. I'm kind of over peak torque at 7000rpm and having to
change down for every hill, even if its not much of a slope.

I'm going to finish off the N/A build I have in the car right now, get a
proper tune and play with it for a while. After that I will be planning
my next upgrade, and I will definitely be looking for more torque...
so a turbo build is on the cards

Cheers... jondee86

[lisaFRANK]

damn good information, you are the man.

will hit you up soon about getting a wideband to start off with. I plan to boost my car with a t25 within the next year. my goal is somewhere around 140-150hp on stock ecu and internals (blue top na 7rib), so im just guessing i would only need like 6-7 psi or something. i just want a very reliable setup with low hp. but def want to listen to your advice and start with a wideband to start learning now as i piece the parts together. eventually ill probably go with the cx racing kit (w/out provided turbo) through you since its cheap and top mount, some fpr you sell, and a used t25 off an sr20 or something.

q: would you recommend against running no bov? i know this sounds dumb but surge sounds so cool, and have not yet seen proof that it ruins the turbo (maybe im just looking the wrong places).
sorry if this question already answered, still reading through all the good info

thanks, lmk if you prefer this not to be on thread and via email or something

[yoshimitsuspeed]

damn good information, you are the man.

will hit you up soon about getting a wideband to start off with. I plan to boost my car with a t25 within the next year. my goal is somewhere around 140-150hp on stock ecu and internals (blue top na 7rib), so im just guessing i would only need like 6-7 psi or something. i just want a very reliable setup with low hp. but def want to listen to your advice and start with a wideband to start learning now as i piece the parts together. eventually ill probably go with the cx racing kit (w/out provided turbo) through you since its cheap and top mount, some fpr you sell, and a used t25 off an sr20 or something.

q: would you recommend against running no bov? i know this sounds dumb but surge sounds so cool, and have not yet seen proof that it ruins the turbo (maybe im just looking the wrong places).
sorry if this question already answered, still reading through all the good info

thanks, lmk if you prefer this not to be on thread and via email or something

I'm still on the fence about the BOV debate.
If you want to read a lot of pro no BOV side of the debate do some searching in the MK2 turbo section on MR2OC. Many members are running NO BOV.

On the other hand if you go to say DSMtuners and mention not running a BOV they will take you for an idiot and start flaming hard despite not being able to show a lick of evidence it's needed for turbo reliability.

[SCLEVIN]

Got an idea for a project. I've got a AE111 Levin 20v blacktop but wanted more power so i've bought a m45 supercharger from a merc c 180k from ebay. Should fit with a custom bracket implace of the aircon pump once removed. My question is could i run it on my blacktop with the stock ecu if im only running 4-5 psi? I have a adjustable FPR ready to fit to get a bit more fuel in but will the stock map sensor work with boost. There was a thread on the old club4ag forum about fitting a 3sgte or 4afte map sensor to make it work but that was on a different 4age ecu. Just want to get it working and have a bit more power till i've saved up the cash to get all forged internals and head work done so i can go with much higher boost controlled by standalone ecu. Which is going to cost £££££.
New to sight but had my Levin for 7 years!

[jinx]

I am trying to emulate is the fat midrange
torque that you get with a large engine, but do it with a small engine
and a turbo

if u can find "neil8586" 4agte posts on the old forum, he achieved (& detailed) EXACTLY what u described. "v8 torque"
megasquirt + tvis + junkyard ihi vj11 turbo(mazda mx6/ford probe). stock bluetop. oe cams
$100 wrx tdo4, ford 2.3 t3 0.48a/r, etc will do the same