MX-3.com

I have a 92 MX-3 with a BPT swap, custom intercooler from a Spearco
core and all custom pipes, including the BPT ECU.  Right now with all stock settings on the engine, including the 9lbs of boost (stock for the engine) I have dynoed at 184.3HP to the wheels.

Now, I wanted to pick your brain a little on the Turbo upgrade.  I want
to swap out the IHI VJ20 for a larger one.  I want to be able to put
down about 250HP+ to the wheels.  A shop I am working with here made
some suggestions, I would love to hear any and all suggestions,
comments, advice and recommendations you all might have.

Here is the list of what they think would work out good:

Precision Turbo T3/T4
Delta Wastegate
Tubular manifold
oil return kit
high flow cat with 3" piping

What do you think of that set up?  Are there any additional components
you would add to that? Turbo RX-7 fuel pump?  Piggy back ECU?

Is there a set up you would recommend?  Please be specific, so I know
what to look for.

I really appreciate you looking this over.  Thanks!!

Elvis
92 MX-3 Turbo

def get the rx7 fuel pump youll need it at that power level especially if you want to be safe

Incredibly enough, while I have my MX-3 all decked out with goodies, I am not mechanically inclined, and when I had the engine put in, I did not know the first thing about turbos.

I was going to start changing some other things, the cam gears, the pulleys, catback, was even thinking of the cams to increase my HP, but the shop is telling me that I am going to long way around and the gains will not get me what I want.

If I want that 250HP, I need to get a bigger turbo but while I am not Mazda expert, I am closer to it than they are, so I thought I would do my homework. I dont want to blow the motor and lay waste to my wonderful MX-3.

I am sure I can get on the right track with the welth of knowledge found in the heads of the people just on this forum.

you should be fine with the stock fuel pump. id go with bigger injectors instead, and some sort of piggyback or standalone unit. we hit 318whp with a stock block, scm63 turbo from precision, bigger injectors and a tecIII unit.

Dude, just turn up the boost....your only running 9psi! 15 pounds should get you close to your 250 goal.... just monitor your a/f ratio, I don't know what exhaust your running but if it's too small, like under 2.5 I'd upgrade.

im sorry but 15psi is reaching the max limit on the vj20 and will greatly lessen the life of the turbo and even at 15 psi you will not see 250. max id say 220-225at the wheels with a fmioc and everything else even tuned great. id say get the turbo manifold that has been produced and then upgrade the turbo to what ever you decide on and have the manifold shop make the flange for it so it will fit. def get an engine management system.

Maybe I should add that while I am aware that I can turn up the boost to get more power, what I would like is to set up a bigger turbo and run at a boost level that I can keep for all around driving and still hit the 250Hp I am looking for. The if(when) I take it to the track, I can turn up the boost and have even more fun.

Right now I have 2.25" cat back with a Weapon R exhaust, I will have that redone to be 3" with a hi flow cat and N1 exhaust

Do you have the gtx bpt or the gtr bpt?

GTX

You dynoed at 184 hp? That seems pretty high.. You sure you dont have the gtr? I am pretty impressed with that number.. Do you have any pics of your engine and car?

The second I get home I will upload some pics for you...I have to find that Dyno sheet as well. It was Dynoed at NOPI St. Louis, right after we put the engine in. And yeah, we were all very surprised, impressed and happy with that dyno pull.

natural born honda killer wrote:im sorry but 15psi is reaching the max limit on the vj20 and will greatly lessen the life of the turbo and even at 15 psi you will not see 250. max id say 220-225at the wheels with a fmioc and everything else even tuned great. id say get the turbo manifold that has been produced and then upgrade the turbo to what ever you decide on and have the manifold shop make the flange for it so it will fit. def get an engine management system.

15-17 lbs is the limit. The VJ-20 is capable of making 250whp....look at mine. The problem is it builds up a great deal of heat at that level but still impressive power for such a small turbo.

like i said 15 psi is reaching the limits of the turbo much after that you are going to be doing nothing but creating more heat. you got good numbers and im hoping to hit the same numbers or higher when i get back from iraq and finish my car. hoping 270-280 to the wheels. like i said i think he should just get the turbo manifold that just got made with the flange they provide and buy a turbo upgrade and slap it on if you want reliable 250whp for extended amounts of time as in the turbo will not last for very long i would guess as its reaching it limits and he could hit the 250 mark a lot easier and with less boost and not be reaching the limits of the turbo.

Here is the first pic, I have available, I will get more on soon.

Here are some of the rest: