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-   -   Should I build an FA20? (https://www.ft86club.com/forums/showthread.php?t=112084)

Nah 10-28-2016 02:06 AM

Should I build an FA20?
 
Do you have a built motor? or maybe lots of knowledge on the subject...

Before I boost (God willing), I'd like to have different boost maps with a variety of

Boost Levels:

6-8 psi

12-14 psi

15-20 psi


Gonna go with an Avo Kit but before I do, I'm going to build my motor.

What pistons, rods, cr ratio, etc.

Thanks for the help

Also, should I break in the motor while n/a or boosted?

jerbull 10-28-2016 03:09 AM

You need to speak with an engine builder. You need a power goal and a budget in mind beforehand. A forum isn't a great place to get engine building advice especially from start to finish. Short answer, you will not hold 20psi on a non built engine so yes you'd need a built motor.

1stGenBRZ86 10-28-2016 03:34 AM

Quote:

Originally Posted by jerbull (Post 2784809)
You need to speak with an engine builder. You need a power goal and a budget in mind beforehand. A forum isn't a great place to get engine building advice especially from start to finish. Short answer, you will not hold 20psi on a non built engine so yes you'd need a built motor.

you build an engine to hold HP not psi. 20 psi on a mitsu td04 is not equal to 20 psi on a precision 6262.

My personal opinion is that you can certainly build your block to reach your goals, as there are a variety of options at the moment, however, the biggest bottleneck on this platform is the transmission. most people are going thru them regularly at 400+whp.

celek 10-28-2016 10:18 AM

PSi is nothing as stated by @1stGenBRZ86
the CFM of the compressor wheel is completely different from different turbos.
You need to talk HP goal not PSi
People have successfully gone 300 400 500 HP on a stock engine for extended periods of time. Keep in mind a turbo only produces that power in boost. If you tune it for 700 HP but baby it around you can claim 50k miles on 700 HP stock engine.

But if you want to actually use said power at minimum I recommend Rods, lower compression pistons and valve springs.

As for Compression ratio availability of fuel octane in you region should help determine that

go_a_way1 10-28-2016 10:28 AM

I am running the 10-12psi range (on a 20g) so it's roughly 250-280whp and that's not bad on the stock motor. Keep in mind like others have said PSI isnt the measurement you use. Too much low end torque is what bends rods

jerbull 10-29-2016 09:48 AM

Quote:

Originally Posted by 1stGenBRZ86 (Post 2784819)
you build an engine to hold HP not psi. 20 psi on a mitsu td04 is not equal to 20 psi on a precision 6262.

My personal opinion is that you can certainly build your block to reach your goals, as there are a variety of options at the moment, however, the biggest bottleneck on this platform is the transmission. most people are going thru them regularly at 400+whp.

The funny thing is the td04 will likely destroy the motor first because of the low end torque it provides.

COO86L 10-31-2016 12:10 AM

I doubt the AVO turbo will reach your PSI goals either.
I'm tuned to 18 PSI on stock internals and baby the shit out of my car. Full boost occurs at 4500 RPM, builds nice and slowly to that point. I like my stock engine for now ;D

My build recipe is as follows:
Pauter or Manly Turbo Tuff rods
CP or JE Pistons, stock CR or 13.5:1
If I lower the CR to 10:1 etc, I'll be using a DI delete kit and running port injection only so I can run an aftermarket ECU
Probably Beehive springs or something similar, they are all about the same price and I haven't read up on pro's and con's on both.
ARP stud hardware
King bearings

I currently made 250kW on a Dyno Dynamics (similar to Mustang, lower than a DynoJet) on a 35 degree Celsius day after driving two hours and had traction issues so ran at 16 PSI.
Next year I plan to build, tune to 20 PSI and add some Nitrous for kicks ;D

Nah 03-27-2017 12:57 AM

Sorry guys for never responding!? But yo, how reliable would a built fa20 be for handing 8psi every day?

swarb 03-27-2017 01:19 AM

Quote:

Originally Posted by Nah (Post 2879772)
Sorry guys for never responding!? But yo, how reliable would a built fa20 be for handing 8psi every day?

Did you even read the replies? :bonk:
Your handle probably answers that.

twag4 03-27-2017 02:12 PM

I blew my engine at less than 400 hp. A rod snapped. The bearing was not spun on the offending rod. I'd say anything over 300whp you are at risk.

weederr33 03-27-2017 02:37 PM

Just build the engine to 500 whp specs and then never go over 300 whp. It's fool proof!

Nah 03-28-2017 01:57 PM

Quote:

Originally Posted by twag4 (Post 2880033)
I blew my engine at less than 400 hp. A rod snapped. The bearing was not spun on the offending rod. I'd say anything over 300whp you are at risk.

Stock bottom end?

Nah 03-28-2017 01:58 PM

Quote:

Originally Posted by swarb (Post 2879776)
Did you even read the replies? :bonk:
Your handle probably answers that.

The question was poorly and lazily asked, not even gonna lie. I just want to hear some stories from the guys who have built or boosted their motors. Or both!

twag4 03-28-2017 06:08 PM

Quote:

Originally Posted by Nah (Post 2880764)
Stock bottom end?

Of course! Rod gave up with no knocking or noises or any kind of warning. From great running to spectacular noise, smoke, and little metal pieces passing me along the pavement. I wasn't on it hard, it was raining, and I had just stabilized my speed at 40mph.


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