ChrisJ
Active member
I donno.
All of the local places in NJ wanted $1000-1200 to do the belt, water pump and idlers. The $700 came from a small shop near my parents in NE PA.
Difference between 1.8l and 1.4l turbo
- Thread starter Mexigga
- Start date
I donno.
All of the local places in NJ wanted $1000-1200 to do the belt, water pump and idlers. The $700 came from a small shop near my parents in NE PA.
thechill_mix
New member
I have the 1.8 too. To me... it makes more sense in the Sonic than the heavier Cruze. It's the best base engine in the class. Beat out only by the Fiesta ST and 1.4T Sonics of course. Acceleration is more than adequate for me. 0-60 times of 8.6-8.9 seconds are respectable in the entry level segment.
I'm sure my next car will be Turbo. For now this will suffice nicely and I have no issue with the engine.
I'm sure my next car will be Turbo. For now this will suffice nicely and I have no issue with the engine.
It will cost way more than the $700 upcharge GM wants for the 1.4 to turbo a naturally aspirated engine. The cost in parts alone will run at least $1500 for a base non-ball bearing turbo kit. That won't include fuel upgrades and tuning, which will have to be done as the ECU will not have the necessary programming to handle the massive changes in airflow.
On top of the cost of parts, you will never be able to push as much boost through the 1.8 as you can with the 1.4. The engine has a higher compression ratio, non-forged pistons, and a weaker rotating assembly overall. Most NA engines top out at less than 10 PSI before they will scatter parts out of the bottom of the engine.
with the 1.4 you are starting with all of that, and can easily push 20 PSI through the stock engine with no internal modifications, 20 PSI on the 1.4 will easily outshine 10PSI on the 1.8.
That doesn't even begin to take into consideration the rest of the drive line, and what it can or can't handle power wise, or the fact that there is no one offering an actual kit for the 1.8.
On top of the cost of parts, you will never be able to push as much boost through the 1.8 as you can with the 1.4. The engine has a higher compression ratio, non-forged pistons, and a weaker rotating assembly overall. Most NA engines top out at less than 10 PSI before they will scatter parts out of the bottom of the engine.
with the 1.4 you are starting with all of that, and can easily push 20 PSI through the stock engine with no internal modifications, 20 PSI on the 1.4 will easily outshine 10PSI on the 1.8.
That doesn't even begin to take into consideration the rest of the drive line, and what it can or can't handle power wise, or the fact that there is no one offering an actual kit for the 1.8.
Last edited:
mitdr774
also a dinner prick
What my goals will be, if I go the turbo route, exceed what I would be comfortable with on a stock 1.4T. Either way I would be looking at strengthening the internals, custom manifold, something in the GT22-25 range turbo, and lots of tuning. The cost to build to the reliable power level I would be after would be about the same for both engines.
The stock rotating assembly in the 1.4 is not some incredibly strong set up. The forged bits are there so they can be made smaller and lighter, yet retain the strength of a bigger and heavier traditional part. Both engines were designed to make roughly the same power, and be efficient.
The stock rotating assembly in the 1.4 is not some incredibly strong set up. The forged bits are there so they can be made smaller and lighter, yet retain the strength of a bigger and heavier traditional part. Both engines were designed to make roughly the same power, and be efficient.
RMinNJ
Active member
I had an LS with the 1.8 as loaner. After driving my 1.4 I noticed the 1.8:
a.) Seemed about the same on power until on hills where it downshifted sooner
b.) Ran slightly higher RPMs on the highway..
c.) Got about 34-35 MPG on the display instead of the 38-42 of my 1.4... but it was a brand new LS.
I was actually impressed.. it was so close to the 1.4 ..I could not see them doing a better job to make
the 2 engines feel the same.
a.) Seemed about the same on power until on hills where it downshifted sooner
b.) Ran slightly higher RPMs on the highway..
c.) Got about 34-35 MPG on the display instead of the 38-42 of my 1.4... but it was a brand new LS.
I was actually impressed.. it was so close to the 1.4 ..I could not see them doing a better job to make
the 2 engines feel the same.
Last edited:
Roughly speaking the 1.4L's ability to move air at peak boost would be similar to a 2.9L engine. I get this by taking (16psi+14.7psi)/14.7psi x 1.4L.
When boosting the engine is basically pretending to be a much larger engine. Using the same kind of math, the 1.8L engine is going to need about 9psi to match the smaller 1.4L.
Assuming that a tuned 1.4L can hit 21psi, the equivalent displacement would be 3.4L at peak boost. To match that, the 1.8L would need 13psi. The problem you will run into is that I don't think the 1.8L's internals are designed to take those sorts of pressures. Cranking boost to 21psi in the 1.4L is only a 16% increase in effective displacement. Adding a large turbo to hit 13psi in the 1.8L is an 88% increase. You would almost be doubling the pressure in each cylinder!
It will be much cheaper in the long run to make power in the factory turbo, though I don't get the sense that people are arguing otherwise.
When boosting the engine is basically pretending to be a much larger engine. Using the same kind of math, the 1.8L engine is going to need about 9psi to match the smaller 1.4L.
Assuming that a tuned 1.4L can hit 21psi, the equivalent displacement would be 3.4L at peak boost. To match that, the 1.8L would need 13psi. The problem you will run into is that I don't think the 1.8L's internals are designed to take those sorts of pressures. Cranking boost to 21psi in the 1.4L is only a 16% increase in effective displacement. Adding a large turbo to hit 13psi in the 1.8L is an 88% increase. You would almost be doubling the pressure in each cylinder!
It will be much cheaper in the long run to make power in the factory turbo, though I don't get the sense that people are arguing otherwise.
It will be much cheaper in the long run to make power in the factory turbo, though I don't get the sense that people are arguing otherwise.
Well that really comes down to what the 1.4 can handle, these are both relatively new engines. So very few have pushed them beyond the factory capabilities; but I suspect this may be a very different discussion five years from now. I have no facts to backup this statement.
opcorn:
$ub$onic
The Sticker Guy
I have found that a 1.8 5 speed is the most reliable combination you can get
I have 2 1.4s and a 1.8 currently and the 1.4s are normally nothing but issues
Sent from my S60 using Tapatalk
JesusTheAgnostic
New member
I haven't heard of a turbo 1.8 Sonic, a lot of talk about hopes and dreams, but not of one actually built. I'd say the 1.4 is a lot of fun, but as with all turbo cars there are problems, the water pump fails, the intake manifold breaks, the turbo blows, the hmm. That's actually all I can think of right now. I'd say if you really wanna have fun and feel like throwing money away trade it in and get the 1.4. The 1.8 though the only thing I can remember right now is that the intake hose cracks.
The 1.4 has a timing chain?! I'm at 96,000 and I was dreading the belt change. Any sources to confirm this?
JTee2017
Well-known member
See this: - - > GM 1.4 Liter Turbo I4 Ecotec LUJ & LUV Engine Info, Power, Specs, Wiki | GM Authority
Also. . in this picture there is no timing belt "shroud" or cover since the chain is internal. See the 1.8L picture below it to compare.
Sonic 1.4L Turbo
Sonic 1.8L non Turbo
Last edited:
JTee2017
Well-known member
Do regular oil changes (4,000 miles or so) with a good full synthetic and you should never need to change the timing chain. A smaller turbo engine like this should have frequent oil changes. . . no matter what GM or other folks say in my opinion.
More importantly, the transmission fluid or gear oil should be changed every 30K to 40K miles. These are tiny but hard working transmissions. The fluid in the automatic will get black in 30K miles or so. Easy to change buy draining about 5.3 quarts out and refilling EXACTLY what you drain out and repeat Three Times. You will need about 17 qusrts for a complete auto trans change.This will rinse and change 93% of the fluid.
So I'm at 96K and I've never changed the trans fluid. Ever. Is there a guide for this?
JTee2017
Well-known member
There are some threads here that have covered that.
But. . look up Youtube videos for the Chevy Cruze automatic.
Here are a couple. . . there are more. Watch them all for best info. Also, important to check final level each time via the side "level checking port" which may require removing the driver side tire.
https://www.youtube.com/watch?v=ITIE1MFSIgQ
https://youtu.be/MyDY3vCgn6c
Last edited:
You probably saved my car with this.
JTee2017
Well-known member
You are welcome.
But really, you need to read a lot here covering 1.4L maintenance.
With 96K on it, I would change the intake manifold. It contains the PCV valve which has been problematic. Also, the thermostat should be changed and it's water outlet and the water pump.
^ ^ ^
Do these things. . . . now. Do not wait. Amazed you have not had any issues yet.
If you have not had problems with these things. . . yo are living on borrowed time. If the PCV valve gets plugged it will likely blow out the rear main crankshaft seal and that is $$$$. Not to mention it will foul and dmage your turbo.
Again. . read. . . read. . . read all you can here about the 1.4L engine maintnenace issues.
I bought a 1.8L. I like the idea and torque of the 1.4L . . I did not want to be constantly on edge about fixing it. I find the 1.8L fine for my general driving.
Last edited: