Has anyone installed a smaller turbo than 14b/T25

[DSM_Roller]

The car in question is a 1995 Talon Tsi AWD w/automatic transmission


Has anyone tried to install a smaller turbo on their DSM? The car is going to be used as a daily driver, the only mods will be appearance and maybe K&N air filter. I know I can just try not to boost, but I have a lead foot. Would a smaller turbo help with fuel economy, and are there any bolt on smaller turbos?

 

[tstkl]

I can get bad gas milage in a toyota carrolla if Im just flooring it 24/7. A smaller turbo won't help much.

 

[truwarrior]

I don't think a smaller turbo will help much, might actually make it worse, maybe just a big laggy one will help


You can run boost source directly to the wastegate, that might help some but how boring

 

[DSM_Roller]

i need to lighten my foot then.

Can stock boost be turned down?

 

[JayRolla]

I dont know about fuel economy, but my brother had a 13g td04 turbo on his car when he bought it. Everything was stock but looks like someone just put that on because thats all they had. All I know is it had pretty good fuel mileage. It spooled very fast and had some alot of power for a little guy. It was stock with boost at about 14psi(knocking) and would beat almost any other stock or mildy modded dsm. We had a couple of friends one with a 2g t25 pushing 18psi not tuned(idiot), and one with a 1g stock 14b. He smoked both of them I think it was due to the spool.

 

[Caithness]

Reducing your boost level from stock to wastegate pressure, maybe 2-3 pounds loss, is not going to help your gas mileage much, but will make your car slower. You pretty much just need to learn some control if you want to improve your gas mileage. To a certain extent it doesn't even matter what you're driving- if you put your foot into it all the time, you're not going to get great mileage. I actually get almost the same mileage in my DSM as I did in my old 4 cylinder Accord because the Accord was so underpowered that I had it floored all the time, while the DSM has enough power to part throttle around.

 

[diamondgst]

If you are trying to get the "lowest" boost possible for your setup...

Take a vacuum line stright from your boost source (the nipple on the turbo near the outlet elbow if its a T25) and run that line directly to the WG acuator with nothing between it. Make sure and leave the stock BCS hooked up if you dont it will throw a CEL. But this is the lowest amount of boost you could possibly run

 

[Quasimondo]

Well, you can run lower, but that involves disconnecting the flapper from the actuator arm. You'll run a mesmerizing 3 psi of boost, the car will be dawg slow and you'll probably get even worse mileage from having to floor it all the time.

Best mod to get is a lighter foot.

 

[No_Skillz]

Or stick a brick behind the gas pedal.

 

[truwarrior]

Better yet, if you want to get really geeky, get a wideband and get off the gas once you start to get a a/f lower then 14 to 1

I can spool atleast a few pounds of boost and still get a 14 to 1 airfuel.

Once you get into higher air flow level the computer will richen the mixture with more fuel to keep things cool and help prevent knock.

I get really good gas mileage cruise on the highway but around town isn't that good.

I think it has to do with the stock cams.

 

[pneumo]

If you want to spend money on stuff that saves gas (which saves money) buy an eprom ecu and use the lean-burn code developed by the dsm-ecu list. Then go to TeamRip.com and get the taller 5th gear.
Other gas saving tips;
Drive slower-on my car cruising at 75 mph burns about 2 mpg more than cruising at 65mph.
Go easy on the throttle while the engine is warming up- the ecu uses a richer A/F mixture when the engine is cold.
Avoid sudden changes in throttle position, which avoids activating the accelleration enrich function.
Look ahead- if you know you'll need to stop soon you can coast a little longer instead of being on the gas then having to brake harder. Coasting in gear and downshifting uses no gas above 1200 rpm with a stock ecu.
Pump up your tires.
Make sure your O2 sensor, plugs and wires are in good condition.
That's all I can think of for now.

 

[tstkl]

a less restrictive exhaust and intake will give you better gas mileage if you can manage to keep your foot off the gas. It takes less air to make the same power because there is less friction, which in turn allows for more air to flow and make more power, but if you can manage to keep your foot off it will help.

also, you can adjust your throttle cable so that when your flooring it, the throttle body isn't open all the way.

 

[biglady112]

That larger the turbo the better gas mileage you WILL get. The fuel responds 1:1 with boost. If you are never in boost, you don't use as much fuel. When I had my talon, it had a 60-1 and 680's. I could get 27mpg in town and over 30 on the highway.


Steven

 

[DSM_Roller]

this is some good stuff, thanks!

 

[MrBoxx]

Or you could install a Tornado in your intake to get more power and better gas mileage!!!

(^ = Defiant lure)

 

[GVR4592]

Buy a car without a turbo.

 

[No_Skillz]

Buy a car without a turbo.

Might as well tell him to ride a bike or walk. Just kidding for all you n/t guys that might take offense.

 

[tstkl]

that is a good point though, I want a bike for the better gas mileage and ease of parking. Also a 500 or 600 would be really cheap and a lot of fun while still kicking most car's ass in mpg's

 

[Caithness]

That larger the turbo the better gas mileage you WILL get. The fuel responds 1:1 with boost. If you are never in boost, you don't use as much fuel. When I had my talon, it had a 60-1 and 680's. I could get 27mpg in town and over 30 on the highway.


Steven

Yeah, if you have a turbo that doesn't start making boost until the mid 3000 range, you can really lean out everything 3000 and below and add more timing. Then you can tool around below 3k and get great gas mileage.