Official 1.8 turbo thread

[$ub$onic]

If you want mpg don't build a race car pretty soon you will be running turbo blue at $8 a gallon

 

[mitdr774]

I dont see why it wouldnt be possible to build a reliable 225-250 WHP carthat could also return good economy numbers. If the turbo is sized so that it wont really be doing much at typical cruise speed and RPM it should hurt much.

A buddy of mine has the Saab 2.0T swap on the L61 in his Cavalier. Its a TD04-14t turbo and it spools FAST on a 2.2L. He is still capable of getting 38 MPG on the highway though.

 

[DevilSonic89]

Im just trying to achieve a whp of 225-250

 

[Preloader]

Add 15-18% (drivetrain loss) to that for your crank hp target. Now your talking 265-295 chp.

For that you'll want a turbo that can pull almost 30 lbs/min airflow at 1.5 PR.

Not many can do that. I think with a K03 and 8psi, you may see 200whp, and compared to the stock 120-ish whp that should be very gratifying.

All these numbers are theoretical btw. But should be pretty close to reality.

 

[Preloader]

I still think the K03 is an excellent choice for a 1.8 boost pioneer, and I don't want to deflate you're enthusiasm.

Standard n/a OEM engines can handle about 8psi. The K03 will gladly make the 250 whp you desire if you allow it to boost higher. Even 12psi would likely get you there. But testing the fortitude of the internals will determine if she can handle that.

The reason I like the K03 for your application is that it has a healthy margin before surge and choke for a wide usable powerband at 8psi, where a larger turbo won't be productive for much power curve at that PR.

K03 will be a great baseline for the first 1.8T Sonic.

 

[Preloader]

As far as a DD 200whp 1.8T Sonic with close to stock mpg, very plausible. Google around and read reviews or watch videos of n/a Honda or n/a Miata 1.6's converted to turbos and you'll see all the fun and practicality that can be achieved.

 

[GunBlade]

I'm going to say if you have a dealer near you you should just go and try and see if you can get a oem one from them since almost any place I have looked online seems meh to me. But if you are willing to do more digging on the sellers then here are 2 places online with the oem borgs. When I get more sleep I will do some serious web surfing for a good buy.

Audi*A4*Turbocharger from Turbocharger pros

1996*Audi*A4*Turbocharger Parts from Buy Auto Parts

 

[DevilSonic89]

one thing that will be hard tho is to lower the compression ratio from 10.5.1 to a lower rate..like 9.5.1 in order to run a higher psi like 10-12

 

[Preloader]

The alternative to lower CR pistons is simply a taller or doubled head gasket.

8psi should be fine with the stock CR, but if you have plans of going higher later, I actually think it would be practical to scout out a 2nd 1.8 engine to build up for lower CR and stronger internals and just swap the whole thing when you're ready to bump the psi.

One other alternative is higher octane with the stock CR. the main issue with CR on boosted applications is the tendency for detonation caused by added heat of more dense air being compressed at that higher compression ratio.

E85 may be the ticket to safely letting you boost 10-12psi without the need to change CR. and remember, turbos respond well to e85 for that very reason, you don't have to sacrifice timing advance (where power is effectively increased).

 

[DevilSonic89]

The alternative to lower CR pistons is simply a taller or doubled head gasket.

8psi should be fine with the stock CR, but if you have plans of going higher later, I actually think it would be practical to scout out a 2nd 1.8 engine to build up for lower CR and stronger internals and just swap the whole thing when you're ready to bump the psi.

One other alternative is higher octane with the stock CR. the main issue with CR on boosted applications is the tendency for detonation caused by added heat of more dense air being compressed at that higher compression ratio.

E85 may be the ticket to safely letting you boost 10-12psi without the need to change CR. and remember, turbos respond well to e85 for that very reason, you don't have to sacrifice timing advance (where power is effectively increased).

E85 in Atlanta not that abundant lol. i was going to tune it on 93 octane tho. will that work fine???

 

[Preloader]

It'll help.

 

[DevilSonic89]

It'll help.

0_o lol but E85 is better??? how about a low boost application..with the ddmw nos kit at a 50 shot???

 

[Preloader]

Especially for your higher than average CR than desired on boosted applications.

I just got a new book that I'm tearing through about turbocharging and adding turbos to n/a engines. I can't put it down. Hopefully I'll be more enlightened on the CR dynamics by the end of the week and will gladly share what I learn here.

 

[DevilSonic89]

Especially for your higher than average CR than desired on boosted applications.

I just got a new book that I'm tearing through about turbocharging and adding turbos to n/a engines. I can't put it down. Hopefully I'll be more enlightened on the CR dynamics by the end of the week and will gladly share what I learn here.

whats the name of the book??? i will also go pick it up. :banana:

 

[Preloader]

The book second from left is a well of turbo education.

The first on left is a must for a beginner to get familiarized with turbos.

I would get them both.

 

[DevilSonic89]

The book second from left is a well of turbo education.

The first on left is a must for a beginner to get familiarized with turbos.

I would get them both.

ok. i believe i saw those at PEPBOYS lol

 

[DevilSonic89]

gmpartsdirect.com: Alternate GM Catalog

should i???

 

[Preloader]

The link doesn't take me to the product, but if it is the GM service manual for the Sonic, I would. If you are indeed planning on building up the 1.8 or even just taking the cyl head off.

And of the books above..... The first on left is great to process the workings of the entire turbocharging system, has a great history lesson and will help prep you for the second book.

The second book isn't PhD level, but could be intimidating without a rounded understanding of TC systems.

Before I start sounding arrogant, I'd like to humble myself by reminding you that this is my first turbo'd car and I knew NOTHING about turbocharging a year ago. But being that I do ALL my own mechanics, I couldn't stay ignorant and expect to work on this car in any depth.

I've spent no less than an hour a day for months to bring myself up to speed, and I'm feeling really confident about my understanding of boost. Also I am going to prove it really soon with my GT2560 upgrade.

 

[DevilSonic89]

The link doesn't take me to the product, but if it is the GM service manual for the Sonic, I would. If you are indeed planning on building up the 1.8 or even just taking the cyl head off.

And of the books above..... The first on left is great to process the workings of the entire turbocharging system, has a great history lesson and will help prep you for the second book.

The second book isn't PhD level, but could be intimidating without a rounded understanding of TC systems.

Before I start sounding arrogant, I'd like to humble myself by reminding you that this is my first turbo'd car and I knew NOTHING about turbocharging a year ago. But being that I do ALL my own mechanics, I couldn't stay ignorant and expect to work on this car in any depth.


I've spent no less than an hour a day for months to bring myself up to speed, and I'm feeling really confident about my understanding of boost. Also I am going to prove it really soon with my GT2560 upgrade.

Im in the same boat as u. i never owned a turbo car as well but i help my friend with his 2005 sti tho, and i learned a lil bit of stuff thru him.

that was the link to the 1.4 intercooler for $156.78 and the temp sensor for $21.57. I will have to do custom piping tho.

 

[Preloader]

I'd say yes. It should be perfect for your project.

The temp sensor mounts into the plastic elbow after the IC, so you may want to purchase that or start to think about how to mount it into your custom charge piping.