Ported intake manifold and MPG

[rsSteve]

For MPG...you are comparing BNR tuned vs. BNR tuned+Ported Intake Manifold ?
It seems like the tune must play a role also to make use of the ported intake manifold?

I'm still on the fence on the porting as its not a reversibly mod and many folks over on the Cruze forum reported a low end torque loss that they could feel.
In theory if I'm revving the motor higher to overcome a lowend toque loss I should burn more fuel?

That many of the posts (both here and there) are tuned and untuned really
confuses the issue. From all my reading it seems like I should port the intake manifold somewhere half way to gain a little upper end power but not lose a lot of lowend torque?

Looking at the page 4 graph;
a.) It's for a DDMworks tuned car.
b.) The blue (no porting) line is below the black (ported) line everywhere except from about 2900 to 3200 where it goes higher... This must be "the dip".
c.) The difference in the dip looks to be about 12 ft/lbs if that.

If one torques their spark plugs at 15-19 ft/lbs.. I doubt one could possibly feel this.
It would be really nice to see a dyno of the stock tune and the stock tune ported where, perhaps, the torque difference is larger ?

As you have mentioned the "low end torque loss" is so minor for what you gain i highly doubt it is even possible to feel. I am untuned and even with knowing about the "low end torque loss" i am unable to feel any difference down low besides the huge improvement up top. (even being untuned that way is much quicker in the high rpms)

I honestly feel it is the placebo affect. When enough people hear and read something enough they start to view it as fact... I dont think we have had a single member here on SOF claim they were able to feel a loss in power, so i wouldnt let that dissuade you.

 

[krakenredbeard]

We are also rs so we have shorter gearing may be more noticeable to non rs owners.

 

[RMinNJ]

Right..the one graph to me showed a small torque loss..how could one really feel it. But the folks on the Cruze forum (albeit with heavier cars) have a whole thread on a how horrible the lowend hit is.. but again, most are tuned so it's hard to tell.

If it were a reversible mod one could try it and see..

 

[Preloader]

Cruzetalk's resident know-it-all basically talks down on any mods in which the stock engineering is altered, and the members seem to lap it up with a spoon.

He denounces this mod where ever he sees it mentioned. Meanwhile the only mods he's done to his car have to do with oil. I don't even think he's tuned.

Careful what you read on Cruzetalk.

 

[SoundWave]

Cruzetalk's resident know-it-all basically talks down on any mods in which the stock engineering is altered, and the members seem to lap it up with a spoon.

He denounces this mod where ever he sees it mentioned. Meanwhile the only mods he's done to his car have to do with oil. I don't even think he's tuned.

Careful what you read on Cruzetalk.

Hey, just throwing this out there, but I'm a coconut oil dealer, and can get it for you at a steep discount.... </sarcasm>

And to keep this on-topic. I've not noticed any dips in power, quite the opposite. When I was doing my test drives (On a private track of course) I kept redlining; as the engine no longer dies off above 5500 RPMs. I used to just wait for the power to drop and then shift; that no longer happens, and the thing pulls until it hits the rev limiter. That is not good for MPGs in case anyone is curious

 

[Preloader]

The tumblers in the intake manifold are there for one reason, and one reason only: create a large amount of tumble in the intake charge to help vaporize fuel in a "cold" engine. This helps lower cold start emissions and keep precious metal content lower.

If you look at the typical EPA emissions cycle, 99% of the total pollutants come from the first 30 seconds of the test - on a 1375 second test! Poorly mixed fuel causes incomplete combustion, and when the catalytic converter isn't at operating temperature, lots of emissions exit the tailpipe.

When the engine is warmed up, the tumblers are not need; fuel is injected on the backs of the hot intake valves while they're still closed. This flashes the fuel into a vapor (and does a nice job of cleaning them too) and mixes readily with the incoming intake air.

They were most likely added because of how hard it is to heat up the catalytic converter on a turbocharged car. The best way to heat up the converter during a cold start is to use plenty of spark retard - the late combustion does less work pushing the piston down and much of the energy goes right out the exhaust port. Turbos LOVE heat, and will spool up - which removes energy (heat) from the exhaust before the converter can get all of it.

^^^THIS^^^

I thinks Scot's hypothesis makes much more sense than any other speculation I've heard. It has pretty much closed the case for me.

 

[Swordsmith]

When I first switched to Flexfuel I had repeated trouble with stalling until the engine heated up. I am currently having similar troubles stalling when going to idle, and one hypothesis is that the O2 sensor in the first Cat is bad. That sensor apparently has a heating element so it will work quickly. Soooo do people with a ported intake manifold have trouble where their engines stall until they have warmed up, in very cold weather? Seems to me that would be a consequence of delayed warming due to tumbler removal.

Also seems to me that if porting increases MPG all the time you are driving, but tumblers improve emissions for 30 seconds each time you start the car, that the next wave of technology for car manufacturers would be some form of retractable tumblers, that tumble the air for 30 seconds or whatever, until the car goes into closed loop, then pulls them out of the way. CAFE should be driving these little innovations pretty hard, shouldn't it?

 

[SoundWave]

When I first switched to Flexfuel I had repeated trouble with stalling until the engine heated up. I am currently having similar troubles stalling when going to idle, and one hypothesis is that the O2 sensor in the first Cat is bad. That sensor apparently has a heating element so it will work quickly. Soooo do people with a ported intake manifold have trouble where their engines stall until they have warmed up, in very cold weather? Seems to me that would be a consequence of delayed warming due to tumbler removal.

Haven't had cold enough weather yet to tell, but based on their predictions for Michigan we may find out very soon

If it does turn out to be a problem, I will pickup another manifold and switch out the ported one for the winter, and pursue an alternative solution.

 

[biged83]

im just trying to get my head around this i have searched all of the different posts on porting the manifold but cant seem to find a straight answer. Can you do this with the stock tune or does it not run right?

 

[rsSteve]

im just trying to get my head around this i have searched all of the different posts on porting the manifold but cant seem to find a straight answer. Can you do this with the stock tune or does it not run right?

Yes you can, I am untuned and have been running it for about 5k miles with zero issues

 

[rsSteve]

When I first switched to Flexfuel I had repeated trouble with stalling until the engine heated up. I am currently having similar troubles stalling when going to idle, and one hypothesis is that the O2 sensor in the first Cat is bad. That sensor apparently has a heating element so it will work quickly. Soooo do people with a ported intake manifold have trouble where their engines stall until they have warmed up, in very cold weather? Seems to me that would be a consequence of delayed warming due to tumbler removal.

Also seems to me that if porting increases MPG all the time you are driving, but tumblers improve emissions for 30 seconds each time you start the car, that the next wave of technology for car manufacturers would be some form of retractable tumblers, that tumble the air for 30 seconds or whatever, until the car goes into closed loop, then pulls them out of the way. CAFE should be driving these little innovations pretty hard, shouldn't it?

Is this the same issue you mentioned here? http://www.sonicownersforum.com/forum/1-4l-turbo-sonic-engine-discussion/15326-stalling-when-going-idle.html

what made you alleviate the MAF as a problem?

 

[biged83]

Yes you can, I am untuned and have been running it for about 5k miles with zero issues

thank you

 

[Swordsmith]

Is this the same issue you mentioned here? http://www.sonicownersforum.com/forum/1-4l-turbo-sonic-engine-discussion/15326-stalling-when-going-idle.html

what made you alleviate the MAF as a problem?

yes. And I didn't eliminate the MAF, I am just saying one hypothesis was the O2 sensor... and commenting on how that sensor might interact with the tumbler removal and cold weather.

 

[ss2000slp]

Someone correct me if I'm wrong here, but the engine shouldn't read from the O2 sensors until it is in closed loop. So even if the O2 sensor crapped out completely, it shouldn't matter until the car goes to closed loop after running for a minute or so.

 

[ss2000slp]

Sorry, should have put this in the stalling thread. Had both links open in different windows.

 

[2014 Blue RS]

From all my reading it seems like I should port the intake manifold somewhere half way to gain a little upper end power but not lose a lot of lowend torque?

No half way porting. Just dremel out the restictor plates. Doesn't take very long.


Then you get this!


And I got check engine lights or anything.

 

[2014 Blue RS]

My MPG may not be the best but I've been doing the same 20 mile drive on cruise control at 72 MPH before and after each change. With the intake and the ported IM my MPG went down slightly. 34.3 to 33.8

Intake presented no noticeable extra power. Just a lot of mechanical noises. With the intake and the ported IM, WOT was improved. Car pulls harder with less delay (throttle response).

 

[SoundWave]

Final results are in on the Post Port MPG numbers. I've also posted this to Facebook, so some of you have already seen this graph.

That's pretty definitive proof that the mods I've done have significantly increased MPGs, when I'm driving in ECO mode with the Cruise on. Been driving with ECO off since, and well, my MPGs are significantly lower, that's mainly due to the extra digit on my speedometer though

Hope to get the Bypass mod done this weekend, will continue to log my mileage afterwards to have more data to share.

 

[TheLorax]

Final results are in on the Post Port MPG numbers. I've also posted this to Facebook, so some of you have already seen this graph.

That's pretty definitive proof that the mods I've done have significantly increased MPGs, when I'm driving in ECO mode with the Cruise on. Been driving with ECO off since, and well, my MPGs are significantly lower, that's mainly due to the extra digit on my speedometer though

Hope to get the Bypass mod done this weekend, will continue to log my mileage afterwards to have more data to share.

Some of this could be due to getting better mileage as the engine wears in a little. Not all or even most of it I'm sure, but some.

 

[SoundWave]

Some of this could be due to getting better mileage as the engine wears in a little. Not all or even most of it I'm sure, but some.

I'm about to break 28,000 miles, I average 600 miles/week. I was already above 20,000 miles when I did the BNR Stage 1, so while it's possible; that would contradict the results of all the anecdotal experience posted in this thread.

No one has posted a loss of fuel economy, I'm just trying to quantify the results I've had. I started tracking mileage on 7/7 and this last tank data was collected on 8/22. That's only 53 days worth of driving to go a total of 5541.3 miles.* I'm fairly confident in my results, but this is in no way a scientific study.

*there are at least two tanks of gas that I did not track during this period because I was "fun driving" after I ported the intake.