16g or 20g on a stock motor??

Scotty2hottie

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Doing a homemade kit will be on e85, 1:1 boost ref, s2000 injectors, etc. No intercooler or meth. Will be mainly spirited street riding.

Looking at the 16g or 20g because the price looks good. I was leaning towards the 16g because I don't know when I will have the money to build a motor. But then i'll be into it more for a bigger turbo when I do.

which got me thinking a 20g now and just live with some lag then i'll have room to grow when I want to. Is it just to much on a stock motor? when will it go positive? Anyone with experience or done it? I cant seem to find a thread, searching "20g" is to small.

thanks guys!
 
Depends on your definition of stock motor. Are you talking completely stock, or at least a spacer, head studs good head gasket ect?

Either turbo will work. The Hahn kits use a 16g I believe, and work alright. The biggest issue with any of the Mitsubishi turbos is the wastegates are always too small. At minimum, port the exhaust housing, and run the bigger 36mm flapper. Otherwise the turbos tend to boost creep do to poor flow.

Your best option would to be to run an external wastegate.

Getting back to power, I've seen a handful off completely stock motors take 10psi or so on e85. If you spend a few extra dollars on a spacer, head studs, head gasket and adjustable cam gears you can get away with as much as 350whp on a stock bottom end. That is really pushing it. 320whp is liveable on a stock bottom end. I did it for a few years.
 
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Thanks murdered! I was in Houston Friday night, great city.

And yeah was going completely stock no spacer. Only looking to make 250-280 for now on e85.

Well would a garret t3/t4 work better? Seeing 50 trim and 57 trim about 100 bucks more.
 
It sure is!

Most turbo kits are based off T3 turbos. They typically flow better then the misu flanges.

"Trim" is only part of turbo sizing equation. You need more info, like inducer/exducer size, and a/r ratio.
 
Then I'm sure you know about tx2k? Been to that in my car in 12. It was a awesome, trying to get this ready for 14. Just something to play on.

So a t3/t04e 57trim with these specs:
compressor wheel: 56.6 / 74.9 mm 57 trim
compressor housing: T04E 0.70 a/r, 4" / 2½"
center section: oil cooled journal bearings
Turbine wheel: 68 trim (stage1)
Turbine housing .63 a/r, 7 bolts outlet flange

Yay or nay? And why you think so? Trying to learn some more. I get the basics of what each is, just fitting it to a platform is what I need to figure out. Most my setups have been nitrous, so this is a steep learning curve. Lol
 
Of course I know of tx2k. That's always a big part of the year for me.

That turbo should work fine. Sounds pretty close to the old srp china turbos. They worked well.
 
Haha, well when I head that way I'll be sure to hit you up! It's such a good time, get tons of runs in.

Just don't want anything to laggy or too small.
 
Be sure if your planning to run it past a 1/4 mile at wot for any length of time( you said getting ready for tx2k), you get something better than a fmu for continued fueling with no meth or intercooler..
 
I had a t3t4 .63ar journal bearing turbo on stock motor with spacer, started spooling around 4-5k rpm and really started pulling around 7.5k rpm.(no gauge just felt that way) Now I have a t3t4 .48ar journal bearing and it seems to spool faster,about 5 to 6k rpm. Haven't been much higher since I need to retune for the new turbo. I Like the quicker response of the .48ar a lil more than the .63ar. Either turbo would work for a stage 1 imho.
 
Thanks for the input.

The hahn 16g or 20g is hard to beat though with the actuator. I know I need to port the wastegate area if I did go that route.

I have an aem 1:1 I'm running no fmu here. Thank you though.

Decision decisions.
 
Internal wastegates with the actuators on them make for a little more hassle for turbo positioning. One more thing sticking out to clear the radiator. Id strongly suggest an external wastegate.

And just an extra not I forgot to add earlier, you'll need to run a hub with a 3 bar to do boost referenced fueling since your doing a 1:1 regulator.
 
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Thanks for the input.

The hahn 16g or 20g is hard to beat though with the actuator. I know I need to port the wastegate area if I did go that route.

I have an aem 1:1 I'm running no fmu here. Thank you though.

Decision decisions.

these turbo's spike A LOT, I ported mine to a hole 1 1/8 inch in diameter and welded an external gate onto it, i think the hole was about the size of my pinky when i started it, by the way this is a 16g. I have no experience from any other turbo's, I built this myself and it is great on the street. It goes positive around 4000 rpms, it hits target boost quickly, max hp is around 350 for these turbos the 20G I hear can go to 400. Here's a couple of pics of the turbo and log. atmospheric pressure on my gm3bar sensor is 1.68v and it goes to 3.17 (target boost of 13lbs) quickly and full boost by 6800 rpm.
This was a quick run on the street and hit target pressure 13lbs at 6800 rpms and at 40%tps.

Be prepared when working on a budget :laugh: to spend lots of money and lots of time getting these things to go fast.....:thumbsup:

specs.jpg


PICT0053.jpg
 
I ran a Hahn 16g on a dodge avenger I had and I'll never go without a ball bearing center after that. Too much lag.
 
Internal wastegates with the actuators on them make for a little more hassle for turbo positioning. One more thing sticking out to clear the radiator. Id strongly suggest an external wastegate.

And just an extra not I forgot to add earlier, you'll need to run a hub with a 3 bar to do boost referenced fueling since your doing a 1:1 regulator.

If the OP has a Gen 1, what you suggest will not work. There is not enough fuel available with only the four stock injectors and a 1:1 regulator. Boost referencing with a Dynojet hub is not some magic that artificially extends the "range" of available injector, only an increase in fuel pressure will do it. That is why Stage 1 kits for Gen 1s always have an FMU included. The new "shimless" FMUs have been working fine so far.:laugh:
 
If the OP has a Gen 1, what you suggest will not work. There is not enough fuel available with only the four stock injectors and a 1:1 regulator. Boost referencing with a Dynojet hub is not some magic that artificially extends the "range" of available injector, only an increase in fuel pressure will do it. That is why Stage 1 kits for Gen 1s always have an FMU included. The new "shimless" FMUs have been working fine so far.:laugh:

Frank if you go back and re-read his first post, he said he has s2k injectors, and has a goal of 250-280. It can work and has been done before, just need to run larger values in the compensation table of the hub. :poke:
 
Frank if you go back and re-read his first post, he said he has s2k injectors, and has a goal of 250-280. It can work and has been done before, just need to run larger values in the compensation table of the hub. :poke:

Missed that, sorry! I still think it's a mistake. With only a 1:1 regulator he will be pushing on the duty cycles, when a better choice (IMHO) is to just get an FMU and run a pc without the hub. I've done hundreds of Busas this way, and they run great. Rob, the next time you are on a dyno, watch how mapping "tracks" or traces through the grid. You would think at 8 pounds of boost (just as an example), the cursor would hit the 8 psi column at around 6K (again, as an example) and then go straight up through the entire column, following the rpm. This is not what happens. The cursor will hit the 8 psi column and then "dance" between 6 psi and 10 psi as it makes its way up in the rpm. PCIIIUSBs with the hub and boost referencing graph do this, PCVs with the GM Map sensor do this through the grid, and Ecu editor does this as well. I don't consider this an accurate way of fueling a turbo setup. BTW, Microtech boxes do NOT do this, they are way more accurate, and as you have said repeatedly - secondary injectors would be the preferred method.:laugh:
 
The flow chart I have says I'm good with s2000s for my goal.

Shoulda just bought an fmu and ecu editor at this point though. Haha... Gawd nitrous is so much easier.
 
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