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Discussion Starter · #1 ·
I have a 1990 mx6 gt. My goal is to get as much hp/tq as possible. I would like to run 75 shot of nitrous. I'm planing on retarting timing. I can't find a good turbo to put on,but sugestions would be appreciated. I'm still doing research. I don't know how much more boost this motor can handle and I will do whatever I need to do to make it safe. I'm looking for ideas for cams, I havn't found any that will do much.

I pulled the motor and tranny, because I blew a headgasket, warped head. The retarded timing was 4 degrees at the time. Right now the motor is completly disassebled. I see no need in upgrading parts *pistons crank ext because from what I understand this motor can handle 300hp.

This motor was from the junkyard it said it had 150k
runing 20lbs boost
intake
catback
all stock internals
aftermarket computer
light rims
5speed all new tranny stock
graphite head gaskets

What can I do to get the most power, and how do I make sure the parts can handle it?
 

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I have a 1990 mx6 gt. My goal is to get as much hp/tq as possible. I would like to run 75 shot of nitrous. I'm planing on retarting timing. I can't find a good turbo to put on,but sugestions would be appreciated. I'm still doing research. I don't know how much more boost this motor can handle and I will do whatever I need to do to make it safe. I'm looking for ideas for cams, I havn't found any that will do much.

I pulled the motor and tranny, because I blew a headgasket, warped head. The retarded timing was 4 degrees at the time. Right now the motor is completly disassebled. I see no need in upgrading parts *pistons crank ext because from what I understand this motor can handle 300hp.

This motor was from the junkyard it said it had 150k
runing 20lbs boost
intake
catback
all stock internals
aftermarket computer
light rims
5speed all new tranny stock
graphite head gaskets

What can I do to get the most power, and how do I make sure the parts can handle it?
well tunning is the key, large turbo + injector + tunning = you are golden..

i made 268 whp at 16psi with exhaust leak causing the turbo to spool late and run rich preboost dip in 10s and then back up. just by fixing the leak, and replace wastegate gasket to copper, i made 291whp with 1psi more . thats a good number on stock f2t with 460 inj and 50trim turbo. now i can wait for the next nepo dyno to see what the 60-1 and my hx35 will do with a little more boost, no nitrous, i notice the 60-1 felt the best around 21psi. but we will see.

tuine ,tune,tune.
 

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Discussion Starter · #3 ·
Nice, thanks for the reply! That response helps me know what kind of numbers I'm looking to get runing a similiar set up. I never got a chance to dyno mine as the motor I got used was as stated used, but hey they're cheap for a reason and now time for the rebuild! Thanks again, Nick
 

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For good reliability the stock (or close to stock) base timing should be used.

Running too retarded base timing will cause a lot more heat to be blown out the exhaust.
Which is good for spool but not good for power.
The trick is to start retarding the timing with your ECU once the turbo starts to boost.
This gives a more tractable torque curve and smoother power.

And there are much easier ways to get to the sort of power levels ademan is talking about.
See the link in my sig' for details on the VF12 hybrid which is good for 300hp at the crank.
At much lower boost levels than you will need with a T3.

A mid size, high efficiency turbo is a much better way to go than a large, fair efficiency turbo.
Same power, quicker spool, lower boost = better in my book.

The only parts I think I would "upgrade" during your bottom end rebuild are the con-rod cap bolts.
As far as I have seen here that the first thing to go when pushing 300+hp.
I'd upgrade them to ARP fasteners, maybe even 1 size larger.

Forged piston would be good but only for insurance against knocking while you are getting the tune right.
Without knock the stock pistons are pretty tough.
 

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Discussion Starter · #6 ·
Awsome, glad I became part of this site and hope to help others with what I learn with this build! I can't wait to get it runing! thanks for everyones help! I'm concentration on geting the motor built and put in here soon! I just got layed off so guess I have to see the good and the bad! * more time for mazda* I'm thinking about keeping stock cam saw a few posts of what cams are out there for f2 and f2t. I'm still trying to play with the site to work with it a little more smoothly. Ps sorry for the bad grammer and spelling its about 5am here! thanks again Nick
 

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I think the stock F2t motor is easily reliable at 300hp+ levels. Hopefully within the next while, gonna try for 320+WHP on Megasquirt, 94 octane with meth injection and my bigger turbo. The way the motor sounds and runs when its tuned, im pretty confident of some high numbers. But yes anything over 350WHP you should probably build the engine, and start thinking about transmission upgrades;)

Tuning is key though, im stock at 15-16psi with stock ECU now while MS gets fixed. If MS doesnt work, im going AEM or SDS.:)
 

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Discussion Starter · #9 ·
eBay Motors: NOS 07005 4 & 6 Cylinder Sniper WET EFI Nitrous Kit (item 140304680077 end time Apr-29-09 19:00:22 PDT)

t3t4 turbo *60*

eBay Motors: 88+ Mazda MX6 626 Ford Probe Turbo 2.2 Head Gasket Set (item 280302254991 end time Apr-13-09 13:33:03 PDT)

I'm having issues finding injectors with my set up what injectors do people sujest? *600 is my guess can't find any though* not sure if 600 good number* I'm still looking on ebay for injectors!
dont think I'm going for aftermarket cam

I'm still looking into megasquirt *thanks for the suggestion! wasn't very familiar before people on here informed me* still trying to get that down, thanks Nick
 

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Discussion Starter · #10 · (Edited)
i'm thinking just rebuild motor with stock parts. I'm thinking of geting LSD and I snapped my old axles. by the way sorry some of those links didn't work they were craigslist links thanks again for everyones help and inspiration! Nick
 

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Injector sizing depends on 2 things;

1. How much power you want to make.

2. How much fuel you want to waste making it.

Here is the formula for how much crank hp a set of injectors can support (with an optimal tune)

cc / 5.1 x number of injectors

So the stock 330cc injectors can support 259 crank hp. With an A/F ratio of about 12.5:1

But most chipped or MS'd MX6's are at sub 11:1 A/F ratio.
Due largely to the fact that the stock & chipped ignition curves are very aggresive for a turbo engine.
And most MS'd engines never see a dyno to get the ignition curve sorted so most are run overly rich as a safety margin.
And most would be very lucky to get over 200 hp ATW on a stock fuel system.

The closest a chipped ECU for our engines comes to a good tune is the Woo's mod.
Woo (Barry) custom wrote his chip after a long process of burning a chip, then dyno testing, tweaking and then burning again.
The chip actually exceeds the capabilities of the stock ECU so a small amount of circuitry mods are required.
This makes the ECU an exchange item only, meaning a working ECU needs to be sent to him.
228 hp at the wheels has been recorded on a Woo's modded engine with totally stock fuel system. Stock Injectors, Regulator & Pump.
Running Nissan SR20 T25G turbo at 12psi with a blow through VAF (this helps lean out the AF ratio slightly as the air temp reference is in the VAF)

Now the big problem is that so far this has only been done on ECU's from OZ delivered MX6's
So it is not known if the USA ECU's will accept the Woo's mod. :shrug:
 

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I didnt know that, because right now im running 15-16psi on a 50trim BB turbo and my afrs are like 12.2-12.4, but as soon as I touch the boost controller I lean out hardcore. the stock ECU and fuel system(except pump?) can hand at least 260WHP, if not a lil more.
 

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I didnt know that, because right now im running 15-16psi on a 50trim BB turbo and my afrs are like 12.2-12.4, but as soon as I touch the boost controller I lean out hardcore. the stock ECU and fuel system(except pump?) can hand at least 260WHP, if not a lil more.
stock fuel system will not support 260whp. never will.
and upgraded pump to me is not a fuel upgrade. you still need a way to get fuel in the motor through injector or additional fueling setup..

I will be installing safc on a member car in a week or 2. as soon as you buy his upgraded injector
 

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I didnt know that, because right now im running 15-16psi on a 50trim BB turbo and my afrs are like 12.2-12.4, but as soon as I touch the boost controller I lean out hardcore. the stock ECU and fuel system(except pump?) can hand at least 260WHP, if not a lil more.
No it can't. Get a dyno plot of your car or any MX6 doing 260Whp with nothing but an upgraded pump, and I still won't believe you.

You can't argue with BSFC (Brake Specific Fuel Consumtion) sure it can be cheated by retarded timing and lean ratios (>12.5:1) at the expense of peak hp.
But not to the tune of 20% or so. (driveline loss)
 

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Actually I just checked the thread regarding Sabbai's 170Wkw pull (228Whp)

And it was running only a t25g from an SR20 engine at a reported 12psi.


My previous post has been edited.
 

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Discussion Starter · #17 ·
awsome I think I'm taking my block crank and head to machine shop tommarrow

rebuilt head stock parts*new valves/springs/keepers*
new pistons
"used connecting rod"
new axle
50 trim turbo
New gaskets

anything elese I should consider?
hoping to do megasquirt still looking into this thanks for the sticky on it!
 
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