Is it mechanically possible to run a stock motor and turbo to get 30+mpg? This guy I know is tooting his horn about an eg civic vx in stock form with a 8psi turbo can achieve that. I don't believe him cuz I know a turbo is all about performance and not economy. I suggessted f22b1 setup would be better?

 

What is an 8psi turbo? Never heard of it.
I get 30mpg city and nearly 40 highway.

It's all in the tune.

 

Just dont stay in boost all the time. Wont change a thing.

 

8 psi s/c maybe?

 

This. Obviously your knowledge of turbo systems is limited. I wouldn't doubt what your friend is telling you because you are running with a false assumption.

 

It is very possible to run a boosted, stock D series and see 30+mpg....even 40+ depending on the chassis. I recall a thread on another forum wherein the OP attempted to build a turbo 50+mpg EG hatch and he succeeded in doing so. If you run a small turbo to pick up the low end slack and rely on the natural Honda efficiency at highway speed (with a little help from the turbocharger to increase efficiency and even out variance in engine load). To run a very efficient, lean setup, it takes very precise lean tune which can be an Achille's heel

 

Yes with no boost = no extra fuel. Last time I checked I was able to achieve 20-25 MPG when I drove the civic as a DD to see what I could achieve. 30 is possible if you watch your boost gauge and accelerate carefully.

 

The 8 psi refers to the amount of pressure setting for the turbo and engine combo. Do you guys think that same can be achieved for a f22b1 in an eg civic? Also, would this only apply to vtec d series?

 

doesn't matter what engine it is. as all the others said above if u keep ur foot out of the pedal and accelerate slowly without boosting u will not be using any extra fuel then what a stock motor uses = same miles per gallon as stock motor gets no matter what motor it is.

 

I know what PSI means. There's no such thing as an 8psi turbo. Like all the uninitiated, people that aren't fluid in turbo speak often use this to denote their level of power when in fact it doesn't mean anything. PSI is a byproduct, not a goal. Horsepower/torque is what breaks things and makes things go fast, not PSI.

 

I have a D15 under my hood, and I really really REALLY don't understand why anyone would want to boost it. Notorious for blowing head gaskets, single cam, no vtec. I also don't get why someone would spend all that time and money to boost a car but only set it to 8 lbs. That car would make like 120 at the wheels in boost. 30 mpg? Probably, I don't doubt it with that motor.

 

If it's what you have then you boost it. 3 years and no issues. And you'd be surprised how fast it actually is. Do it right and you won't have any regrets.

And again, 8lbs/psi means nothing.

 

Maybe if you had a monkey do the tune. Anyone with even a modicum of skill could coax 150whp at 8psi, assuming the turbo isn't ridiculously small.

 

If that is an ignorant post then I do not know what is? Not to mention not knowing much about the D15 and VTEC is a noob response. At 8lbs, depending on turbo you could hit 170-180 whp.

 

My point being, it's a slow eco motor. I have it and I have taken mine apart and put it back together without any problems. The D15B7 is notorious for blowing head gaskets too. If you are going to take the time to sleeve, stud, built, and boost a motor. Why not do something worth while like a B20 under 15lbs?

 

It's all preference. Sometimes budget. If all you have is cash for a build and not a swap then it makes perfect sense.

And WTF is 15lbs? What does 15lbs get you? Read my lips. PSI means nothing. Start talking in horsepower if you want to sound knowledgeable.

 

lbs=pounds

If you want me to talk horsepower I will, every 15 pounds of boost doubles your horsepower. Why not go all the way when you are so close?

 

Because not everybody has the money for a swap? If I had infinite funds, of course I'd go with a 2.0L+ H or K series motor, fully built and putting down 300whp or more. But unfortunately, there are these funny things called bills and debts, so I'll enjoy my Y8 with an LPT setup.

 

You don't just say "I'm building my b18 and plan on running 18psi of boost".
You can run it 18psi, but you don't know what you're number will be. PSI is not some magical number. You make goals and adjust your boost accordingly. If you want to get real technical, you could go by bar, which is just another way of calculating boost. Either way, using lbs is wrong.

 

You are not listening. What you're spewing is your own opinion. If I, or anyone else, chooses to rock a D-series leave it at that. If you do not understand the choice then I can't help you. Your lack of understand does not make the choice less valid. Do what you want with your time and money.

 

Which is why I decided to save up for a better engine than polishing a turd, why do you think I haven't boosted my D15B7 yet?

 

Really? So, if I run a 14b at 15psi, I will make 240whp? And if I run a 20g at 15psi, I will also make 240whp, regardless of the fact that the 20g is flowing more air at that pressure ratio?

 

Then that's your choice.

 

Swap it, a civic is still an econoshit box. You can only make them "quick", not fast. You want fast, these cars cannot handle that kind of power without reinforcing the chassis. Besides, the wheelbase of these cars are holding them back...

 

And what a late 80's V8 Ponny does not have chassis issues. Why do I have a feeling this forum is starting to be trolled by these guys?

For your information, the Civic is a unibody, and the only issue is sub frame tear out which only comes from a larger torsion bar, not from power. Also take into mind the SI does not have this issue like those that are of the EX and lower sub-models.