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My ambition is to run 10psi on a GT2871R on a rebuilt FS-DE. Any opinions or suggestions fell free to express them

Rebuilt FS-DE:
Tanked and honed block
Reconditioned crank
OE flywheel
F1 Stage 1 clutch kit
ACL main and rod bearings and thrust washer
B&P connecting rods
NPR 9:1CR pistons
Rebuilt head (new valves, springs, lifters, cams, gears)
DSM 450cc injectors
ARP studs
Felpro full gasket set
Gates Timing belt and tensioner kit
Enginetech oil pump
Mazda OE water pump
A/C delete

Turbo kit:
GT2871R with IWG
Stainless steel manifold (T2 flange)
GReddy FMIC
Custom 2.5" FMIC piping
MAF run on the intake side
Type S BOV
2.5" turbo back exhaust with Corksport DP from MS Protege
TurboXS MBC
Apexi Turbo Timer
Autometer A/F, EGT, Boost, Oil Pres gauges (mounted in center trim under stereo)
Walbro 190 fuel pump

That's the gist of it. I'm sure I forgot some things. Trans will also be rebuilt (bearings, syncros, gears etc). Let me know what you guys think.
 

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My ambition is to run 10psi on a GT2871R on a rebuilt FS-DE. Any opinions or suggestions fell free to express them

Rebuilt FS-DE:
Tanked and honed block
Reconditioned crank
OE flywheel
F1 Stage 1 clutch kit
ACL main and rod bearings and thrust washer
B&P connecting rods
NPR 9:1CR pistons
Rebuilt head (new valves, springs, lifters, cams, gears)
DSM 450cc injectors
ARP studs
Felpro full gasket set
Gates Timing belt and tensioner kit
Enginetech oil pump
Mazda OE water pump
A/C delete

Turbo kit:
GT2871R with IWG
Stainless steel manifold (T2 flange)
GReddy FMIC
Custom 2.5" FMIC piping
MAF run on the intake side
Type S BOV
2.5" turbo back exhaust with Corksport DP from MS Protege
TurboXS MBC
Apexi Turbo Timer
Autometer A/F, EGT, Boost, Oil Pres gauges (mounted in center trim under stereo)
Walbro 190 fuel pump

That's the gist of it. I'm sure I forgot some things. Trans will also be rebuilt (bearings, syncros, gears etc). Let me know what you guys think.
hey man if you went through with the turbo build i wanted to ask how much power did you make and how reliable could you go 50,000 miles no issues or were you having to baby the engine every other week
 

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hey man if you went through with the turbo build i wanted to ask how much power did you make and how reliable could you go 50,000 miles no issues or were you having to baby the engine every other week
He never went through with the turbo build.
Turbo's are unforgiving when you get things wrong, bad tune, weak pistons, bad engine work... so either it works or it blows up, you could install all that stuff, baby the car all the time and get 100 000miles out of it, but if something isn't right the first time it's under full boost might be the last time it runs.
Spike94 was making the same mistakes everyone makes during a build, throwing everything and the kitchen sink into the engine and some of his choices weren't the best. 9.1:1 compression ratio is too high for a custom turbo build, it reduces the maximum boost possible on pump gas and is less forgiving when tuning (closer to pre-ignition).
The turbos (GT28, HX35) where both too big for his HP goals of 215-230hp, they both perform best putting out 300 hp + worth of air (higher efficiency area), If the FS was a high revving engine these turbo's could work but based on the fact the FS makes more torque than HP it breaths well at lower RPM's unlike Honda engines, a smaller turbo would spool earlier and with goals of adding 100hp would give the car a longer boost powerband, having full boost for 3000rpm is better than 1000rpm.

Like everything it's money or time, the more research you do the less money you waste but because everyone's car build is their own personal custom project and there is no perfect recipe for every car, often just spending money can lead to more time and money wasted (replacing parts and trying again).

For any turbo build you need Pistons and Rods that are strong enough to handle horse power goals.
The proper compression ratio to handle boost.
A properly sized turbo for your power goals and RPM band.
A strong enough head gasket to handle increased cylinder pressure.
Tri metal bearings to handle crank travel under boost (they allow a slight bit of bearing deflection keeping them out of contact with the crank).
Enough fuel.
Proper tuning.
Proper assembly.
Unless you a nut job that wants 500 hp from a 115hp motor, when done properly a turbo build can be as reliable as the engine was in N/A form.

Can the factory pistons and rods handle an extra 10lbs minute air pressure. Do factory head bolts and a Felpro head gasket hold up to the pressure. What type of crank and rod bearings are used by Mazda in the FS-DE.
Answer these questions and you will know if the FS-DE can be boosted in factory form or it's a bad starting platform for a turbo build. If you have to drop 3000$ into the motor to start a custom turbo build it's the wrong engine to use for a turbo build, you want something that if it blows up you can just grab another one from the junk yard, do the headgasket and throw it in the car.

Think of it this way:
- your tuning window is a log and you have an axe.
-The more that's added to the engine (extra duration cams, high comp pistons... = more heat) narrows the width of the log.
-The factory engine is like a sheet of plywood.
-The built engine is a mural made of fine china that cost you $5000.

The first time you throw the axe at the log (attempt a reliable tune) do you want the log to be thick or thin?
Do you want the log sitting in front of the plywood or the expensive mural?

A forum member in the 1st gen section is running a 1st gen MX6 turbo on his 2L ford zx2, although he chose the wrong turbo to build around, all he needed was a custom manifold, pipes, inter cooler and tune. He's running 15psi reliably for very little money.
 
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He never went through with the turbo build.
Turbo's are unforgiving when you get things wrong, bad tune, weak pistons, bad engine work... so either it works or it blows up, you could install all that stuff, baby the car all the time and get 100 000miles out of it, but if something isn't right the first time it's under full boost might be the last time it runs.
Spike94 was making the same mistakes everyone makes during a build, throwing everything and the kitchen sink into the engine and some of his choices weren't the best. 9.1:1 compression ratio is too high for a custom turbo build, it reduces the maximum boost possible on pump gas and is less forgiving when tuning (closer to pre-ignition).
The turbos (GT28, HX35) where both too big for his HP goals of 215-230hp, they both perform best putting out 300 hp + worth of air (higher efficiency area), If the FS was a high revving engine these turbo's could work but based on the fact the FS makes more torque than HP it breaths well at lower RPM's unlike Honda engines, a smaller turbo would spool earlier and with goals of adding 100hp would give the car a longer boost powerband, having full boost for 3000rpm is better than 1000rpm.

Like everything it's money or time, the more research you do the less money you waste but because everyone's car build is their own personal custom project and there is no perfect recipe for every car, often just spending money can lead to more time and money wasted (replacing parts and trying again).

For any turbo build you need Pistons and Rods that are strong enough to handle horse power goals.
The proper compression ratio to handle boost.
A properly sized turbo for your power goals and RPM band.
A strong enough head gasket to handle increased cylinder pressure.
Tri metal bearings to handle crank travel under boost (they allow a slight bit of bearing deflection keeping them out of contact with the crank).
Enough fuel.
Proper tuning.
Proper assembly.
Unless you a nut job that wants 500 hp from a 115hp motor, when done properly a turbo build can be as reliable as the engine was in N/A form.

Can the factory pistons and rods handle an extra 10lbs minute air pressure. Do factory head bolts and a Felpro head gasket hold up to the pressure. What type of crank and rod bearings are used by Mazda in the FS-DE.
Answer these questions and you will know if the FS-DE can be boosted in factory form or it's a bad starting platform for a turbo build. If you have to drop 3000$ into the motor to start a custom turbo build it's the wrong engine to use for a turbo build, you want something that if it blows up you can just grab another one from the junk yard, do the headgasket and throw it in the car.

Think of it this way:
- your tuning window is a log and you have an axe.
-The more that's added to the engine (extra duration cams, high comp pistons... = more heat) narrows the width of the log.
-The factory engine is like a sheet of plywood.
-The built engine is a mural made of fine china that cost you $5000.

The first time you throw the axe at the log (attempt a reliable tune) do you want the log to be thick or thin?
Do you want the log sitting in front of the plywood or the expensive mural?

A forum member in the 1st gen section is running a 1st gen MX6 turbo on his 2L ford zx2, although he chose the wrong turbo to build around, all he needed was a custom manifold, pipes, inter cooler and tune. He's running 15psi reliably for very little money.
you don’t understand how happy i am for a reply on this forum but i have a couple questions while you’re here so i want max around 250whp and around the same numbers in pound feet i was wondering if the fsde takes better to N/A mods than turbos long term i saw someone in a forum talking about it but i have been thinking about swap options and i think i found the most effective ones for people that want to go 4 cylinder i’m not too sure if the bp dohc motor from the 7th gen familia fits in relatively easy but i was thinking of that swap since i’m pretty sure it’s similar if not the same as the miata motor and the other swap is a speed protege but i have read that those motors are just plain fsdes with a turbo kit no stronger internals was wondering if the bottom end was built up could this make my power goals turbo is what i’m trying to go with what are your thoughts on those motors firing in these cars and would there be substantial work needing to be made to make it all work thank you for you’re time
 

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you don’t understand how happy i am for a reply on this forum but i have a couple questions while you’re here so i want max around 250whp and around the same numbers in pound feet i was wondering if the fsde takes better to N/A mods than turbos long term i saw someone in a forum talking about it but i have been thinking about swap options and i think i found the most effective ones for people that want to go 4 cylinder i’m not too sure if the bp dohc motor from the 7th gen familia fits in relatively easy but i was thinking of that swap since i’m pretty sure it’s similar if not the same as the miata motor and the other swap is a speed protege but i have read that those motors are just plain fsdes with a turbo kit no stronger internals was wondering if the bottom end was built up could this make my power goals turbo is what i’m trying to go with what are your thoughts on those motors firing in these cars and would there be substantial work needing to be made to make it all work thank you for you’re time
Every engine is more durable in N/A form. Forced induction increases cylinder pressure, heat, crank pressure, and pressure on all gaskets and seals.

I am not well knowledge in the FS-DE motor, don't know it's factory compression ratio, it's actual wheel power output or it's potential.

There are N/A tuned 4cylinder motors that can be pushed to 250hp without forced induction but they make 200hp stock.
I would guess that a cold air intake, custom intake manifold, 3angle valve job, performance cams, head port work, 10:1 pistons, headers, full performance exhaust, higher octane fuel and advanced timing might yield 35 wheel hpr.

As far as turbo charging goes research will save you money and time.
Do any MX6.COM members reading this thread know of any 4cylinder 2nd gen turbo builds/ members to search for on the forum that won't end up dead ends like this thread?

Don't go with the speedprotege motor it can't handle the high bosst needed to make 250 reliably in stock form.

If you want to run boost reliably on an N/A motor you need to lower cylinder compression. You can do this one of 3 ways: -lower comp deeper dish pistons.
-copper head gasket spacer. BMW guys run high boost on N/A engines reliably.
-porting the combustion chambers on the head increasing the volume of 1 (combustion chamber) decreases the value of the cylinder compression.
So on an engine with flat top piston with 50cc combustion chambers running 10:1 compression rating, if you port the combustion chambers to 55cc the compression ratio would be 10% lower 9:1 comp.
With dish or dome piston, the piston volume must be taken into account, with bore, stroke, compression ratio, head gasket thickness and combustion chamber CC the piston volume can be calculated.

If you're willing to swap engines and install a turbo, I recommend getting a junk yard T3 and install it.build and tune around that on a budget, you can use junk yard intercooler pipes and fittings and intercooler from various factory turbo vehicles...

Start with low boost and work your way up, if all goes well lower compression ratio and run more boost.

If my suggestion sounds complicated, an engine build and turbo instal using expensive universal performance parts is more complicated and expensive.

Remember wheel and block horsepower are two different things 250 wheel hp is a jump from stock bhp. The clutch, suspension and brakes will need upgrading and ever old factory bushing will be put to the test.

All of us do the same thing, try to fly before we can walk, learn to build and turbo and tune before you attempt a complete build.
My 88 626 build has thousands of hours work so far, there is a lot of aftermarket stuff and new stuff on this car, with everything I'm throwing on it that I purchase over the last 22 years there will be over 20 000$ worth of parts. The car would never be worth the cost of parts, forget all the custom work, paint, porting....

The irony is the 626 gt its replacing had about 3500$ invested (cost of car and all the parts I put on it, lots of time and work was involved and it ran 30 psi the replacement 626 wont be any faster just handle a bit better, be more resistant to rust and look better.

Have fun with what you have, repair and modify what you can and upgrade what you need to.
And weld or have welded the differential shaft to the outer housing of the differential if you want to run boost.
A forced induction motor when properly set up can be much faster than an N/A tuned motor with the same peak hp and torque because it's not about peaks it's about how long (many rpm) the car puts down more torque at the wheels.
 
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