Torque hole discussion

[jeebus]

OK OK, I know there are many discussions on this subject. But I thought maybe this could be a place where we discuss all the various methods attempted to remedy it, and any speculation as to why it exists in the first place.

I've owned ~20 cars and I've never had a car with such a rapid drop in the middle of the powerband. I also haven't had any cars with such small displacement, without a turbo, that have this much low-end grunt. I think the car is great for cruising in town this way. I also think it pulls pretty well from 4500-7000 or so. But if you are in the mood to drive "briskly", that hole in the middle ruins it for you.

Based on the various threads, dynos, etc...it seems there are mods that make the hole less noticeable or shorter, but none that eliminate it (other than forced induction).

So I propose this thread be used to discuss all realms of modification, and specifically what they did to the torque dip. Did they make it better? worse? If they made it better, how so? Did it affect other aspects of the powerband? Did you lose some low-end, top-end?

Also, this thread could be used to propose suggested fixes to the community. Let's eliminate this hole from the car's personality....without a snail.

:happy0180:

[Opposed]

Looks like Visconti's e85 tune is the closest thing to eliminating it in N/A form that I have seen so far.

[jeebus]

Originally Posted by Opposed

Looks like Visconti's e85 tune is the closest thing to eliminating it in N/A form that I have seen so far.

Yeah, and while I like that...e85 just isn't a viable option for many of us. I live out here in California where e85 is not readily available. When it is, it's not worth the price. For example, right now it's 4% cheaper than gas. Since it gets roughly 65% the mileage of gas, that makes it a HUGE premium to run for us out here in our daily drivers. It's a valid option for track days though.

[2forme]

Originally Posted by jeebus

OK OK, I know there are many discussions on this subject. But I thought maybe this could be a place where we discuss all the various methods attempted to remedy it, and any speculation as to why it exists in the first place.

I've owned ~20 cars and I've never had a car with such a rapid drop in the middle of the powerband. I also haven't had any cars with such small displacement, without a turbo, that have this much low-end grunt. I think the car is great for cruising in town this way. I also think it pulls pretty well from 4500-7000 or so. But if you are in the mood to drive "briskly", that hole in the middle ruins it for you.

Based on the various threads, dynos, etc...it seems there are mods that make the hole less noticeable or shorter, but none that eliminate it (other than forced induction).

So I propose this thread be used to discuss all realms of modification, and specifically what they did to the torque dip. Did they make it better? worse? If they made it better, how so? Did it affect other aspects of the powerband? Did you lose some low-end, top-end?

Also, this thread could be used to propose suggested fixes to the community. Let's eliminate this hole from the car's personality....without a snail.

:happy0180:

I think it's a tuning issue mostly.

@Visconti has been able to remove a majority of the dip through tuning. Take a look at the virtual dyno comparison of my car with before/after tune. I know it's a virtual dyno, but I've seen the program be pretty damn accurate before. Not to mention it recorded a pretty accurate stock curve.

[jeebus]

wow. that's the best I've seen short of FI.

[2forme]

Originally Posted by jeebus

wow. that's the best I've seen short of FI.

yea, I'm sure it will do better once I add a header and retune it with John. If anyone ever actually RELEASES a header *cough* Nameless *cough*

[jeebus]

Originally Posted by 2forme

yea, I'm sure it will do better once I add a header and tune it with John.

I wish it was with pump gas though.

[2forme]

Originally Posted by jeebus

I wish it was with pump gas though.

That chart will be coming very very soon. I should be finished with my tank of e85 today and will be putting it back to 93.

[Hawaiian]

If my car ever gets out of the dealer I'll have a few dyno's to post.

[Dimman]

It's not a hole. It's a shit-ton of torque (for a 2.0L) at low rpms.

[serialk11r]

Originally Posted by jeebus

Since [E85] gets roughly 65% the mileage of gas, that makes it a HUGE premium to run for us out here in our daily drivers. It's a valid option for track days though.

71% mileage at worst. This engine is direct injected and high compression, I think 75% is closer to what people will actually see.

Aside from that, the only way you'll change the shape of the powerband in this regard is changing the intake manifold to one with different length runners.

[2forme]

My car averaged 29-30 mpg on e85 with mostly hwy driving. Visconti's tune of course.

[TurnOne]

Not sure I can help, but interesting to me is that I have 2012 Ducati (new engine design) and it has a torgue dip as well. About 4500 RPM or so. I have just learned to keep the revs above it. I presume I will learn to do the same on this car.

Wonder what is going on with these new engine designs.

This car has great low end torgue and drives real easy around town.

Chris

[CBR600RR]

Originally Posted by 2forme

That chart will be coming very very soon. I should be finished with my tank of e85 today and will be putting it back to 93.

Whats your take on how the car feels with ~198 WHP in comparison to ~160 WHP?

What do you estimate the 0-60 and 1/4 times might be now? breaking the 14's?