3.8 L GT Mods for best performance

6573 Views 27 Replies 10 Participants Last post by Sabertooth^2, 19 d ago

Mr.Green

Discussion Starter · Dec 28, 2020

Hello!

I've just joined the site after finding it, well yesterday. I am hoping i'm doing all according to the sites standard but I am still learning to find my way through the forum. But hello from me

Now my question is, If I want to increase the HP / acceleration of my Eclipse to the max possible without causing any potential damage to a car for instance using a turbo on the engine and the risks that come with it. What are the other mods you recommend for the maximum output for the vehicle? Or is there a safe way to put in a turbo which wouldnt ever be a cause for problems in the car? I want it to live as long as possible, with the best performance I can get out of it, without me having to get my hands too dirty as I am quite the novice to cars yet even though id love to learn, havent had neither space or tools to do much and thereby my learning has been lackluster.

Thank you for any and all replies!

1 - 20 of 28 Posts

CyberClown18

· #2 · Dec 28, 2020

Putting a turbo in a GT is a challenge, so if you have no experience, I wouldn't do anything that involves a turbo. A cold air intake, a cat back exhaust, and headers should give you some extra power and aren't too difficult to install.

Sabertooth^2

· #3 · Dec 29, 2020

Cold air intake, 2.75" exhaust, Fastworks tune, upgraded clutch if manual, headers, and you'll see around 270-275whp. It'll be quicker than many other similar power V6 vehicles with a wider powerband, and less drivetrain loss than RWD and AWD vehicles

It's a very difficult car to put a turbo on. With one though, around 450whp has been done. Which is oddly less than the GS has done with a turbo. If you want to pass the 300whp mark, a GS is cheaper and easier. But a 275whp NA GT will be as reliable as stock.

For a novice, I strongly vote staying NA and on a GT.

CyberClown18

· #4 · Dec 29, 2020

Wish I saw some of these GS turbo builds before selling mine for a GT 😕

Instagraham01

· #5 · Dec 29, 2020

There is a flex fuel kit for the 4g gt eclipse, i know doing that, cold air, exhaust, bigger injectors and a nice tune can really go along ways

pcfreak4

· #6 · Dec 29, 2020

Instagraham01 said:
There is a flex fuel kit for the 4g gt eclipse, i know doing that, cold air, exhaust, bigger injectors and a nice tune can really go along ways

Don’t think you need bigger injectors if you aren’t going boosted

Sabertooth^2

· #7 · Dec 29, 2020

For ethanol you do (flex fuel)

Cooldude01

· #8 · Dec 29, 2020

How’s about: long tube header+catless Xpipe+ported manifold, bigger and Throttle body+bigger injectors+TUNE will give you about 385 whp.
This is the easier way compare to put the turbo to already cramp space in the engine and still have the reliability of stock. 😀 😀 😀

Sabertooth^2

· #9 · Dec 29, 2020

That won't get 385whp. Not even close. For that NA you'll need to be running nitro. Methanol would get you close, but isn't enough still.

You'd be asking for 110whp from an intake manifold and throttle body upgrade.

Cooldude01

· #10 · Dec 29, 2020

I believe one of the old members in here did that before. I think his name was 360jeepboy and he posted in his signature.
I’m about to go that route and find out myself..🤞🤞🤞

pcfreak4

· #11 · Dec 29, 2020

Sabertooth^2 said:
For ethanol you do (flex fuel)

Depends on the duty cycle of the injectors on regular gas
But yes, probably do

Sabertooth^2

· #12 · Dec 30, 2020

Cooldude01 said:
I believe one of the old members in here did that before. I think his name was 360jeepboy and he posted in his signature.
I’m about to go that route and find out myself..🤞🤞🤞

The start of his signature is "LS2". That's a Chevy V8, I think it was his Camaro he was talking about.

You'll see about 290-300whp with a well done intake manifold porting and matched throttle body though. Head porting, cams, and valve work, 350whp has been seen around here NA.

Slippercream

· #13 · Dec 30, 2020

Most other bits of info you can search for.

If you're wanting to make power, FI is still the best way to get your numbers. N/A, it's easier to make power because of the displacement, and MIVEC engagement from the OE tune is good as it is - but could always be better. But, nothing like boost to turn up the numbers.

Stock crank is good to about 600hp / 600 lb-ft of torque. It's the same basic design of a crank you'd find in a 6G72 (i.e. 3000GT/GTO). It's been a while, but I believe it's a dead ringer with that of a 6G74 (3.5L). Just a difference in stroke gives you that 3.8L displacement on all cylinders. Where you'll fall short is pistons and rods - which are kinda shit. Don't expect to reliably make power with these on continuous duty past 350hp / 6lb of boost. There are several top-notch shops who have tons of experience with Cyclone engines. Just do a search for a lot of the old posts and you'll find some names.

It is going to cost you though. Remember that the 4G is not an Evo. No catalogs to choose from. No "power packages" to make it easy.

Good luck.

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Sabertooth^2

· #14 · Dec 30, 2020

6G74 is different stroke but same journal sizes and length.

Pistons and rods are unique, but I may be doing a production run this spring of Wiseco pistons and BC rods.

If it were a GS it would be almost as easy as an Evo, as all but a downpipe can be sourced already. (Sensors, manifold, turbo, boost controller, universal piping kit, etc). GT complicates things, but you can buy a pair of GT manifolds that go to a 3" V band for about 2k

Mr.Green

Discussion Starter · #15 · Jan 17, 2021

Thank you all for the replies! Gonna read through them now, I forgot my account for a while there

But now i've got it on my home PC and should be more active! Just got a multimedia system for my 4G, so first upgrade towards making it a better daily

Mr.Green

Discussion Starter · #16 · Jan 17, 2021

Forgot to mention that the car is also already sporting 320 Horsepower after tuning it at a local shop of mine! So it's not too bad but I would like it to be a bit louder, for instance an exhaust! Any specific ones you recommend or just any really, that are catback?

Excuse me if I butcher any of the terms or have no idea what they mean

Sabertooth^2

· #17 · Jan 17, 2021

Mr.Green said:
Forgot to mention that the car is also already sporting 320 Horsepower after tuning it at a local shop of mine! So it's not too bad but I would like it to be a bit louder, for instance an exhaust! Any specific ones you recommend or just any really, that are catback?

Excuse me if I butcher any of the terms or have no idea what they mean

320 according to whos dyno? Typically they do about 275whp with a catback, tune, intake, and headers

Mr.Green

Discussion Starter · #18 · Jan 17, 2021

According to the person who sold the car to me. It's very possible that it is indeed less than that, I would not be surprised tbh. But what I've got to go on until I try it somewhere, 320 is the number.

But seeing as it was described as having been done "by a friend for a friend" by prior owner it may be iffy regardless xD

majin

· #19 · Jan 23, 2021

start maxing out injectors about 280whp, gonna need to upgrade those.

Slippercream

· #20 · Feb 14, 2021

Oh hey Majin! Been a while man.

You ever get that AWD project running?

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