335i guys may have to help Nissan with GTR

[Ragenikon]

those pro drivers are complete idiots. a stock 135i gets walked by a m3. keep up i would say until around 60mph, saying around half a car back. FWIW, try it yourself, see what happens, the 135i traps too low to compare with the m3 esp in races over 70-80mph.

I was just relaying what they conveyed to me, no offense meant. I donno if I'd go as far to call them idiots though, i don't think i met one that had under 20 years experience haha. I assumed they didn't mean "keep up" by means of nose to nose....i assumed keep up as in, it didn't burn the 135i thats all. And believe me man, if i had an M3 to try it with you know i would :wink:

Originally Posted by Fast kiwi

I drive both cars on a daliy bases.. The 1er is faster.. end of story..

I had 135i (auto) up against an M coupe the other day (we both race) and if it werent for the lack of an LSD the 1er would of taking the M on a short circut.. as it was stock to stock, the M couldnt even pull away.

Makes you feel warm and fuzzy inside doesn't it haha

[mikeo]

rcracer_tx and Sinner,
Cool it boys--don't go there.

[rcracer_tx]

Originally Posted by Sinner

There's many more running ridiculously bad ET with insane trap speeds. Maybe you should pull you're head out of your ass and surf some forums instead of Youtube.

Alright, show me the Supra's that are running 13's @150mph+ trap speed. I backed my information with proof, instead of information with nothing to back it up. Working at a tuner shop, I have been there when many Supra's were being built, and am very aware of there performance. The Supra's tend to have high trap speeds because of Traction, not lack of torque.
sub 9 @ 158?

http://youtube.com/watch?v=SXL9UN1j7js&feature=related

I'm done Mikeo, just had to clear the water on some misinformation.

[1er junkie]

Originally Posted by jeremyc74

If torque ruled, all supercars would be diesels.

Audi and 12 hours of sebring That car dominated.

[jeremyc74]

Originally Posted by 1er junkie

Audi and 12 hours of sebring That car dominated.

So one example out of all the race cars out there, and that makes it right? Come on now!

[Rye]

Originally Posted by jeremyc74

So one example out of all the race cars out there, and that makes it right? Come on now!

The top finishers in the LMP1 class for this past weekends 24hr Le Mans were all turbo diesels leaving the rest of the classes with NA engines waaaay behind.

[taiheung]

On road choose torque over hp as you will not legally ever be able to take advantage of the greater number ponies.

[J Tyler]

Originally Posted by Sinner

Duals will make more HP but they'll lose torque. HP will win you Dyno contests, torque will win you races.

Yup. That's why NASCAR cars are way faster than F1 cars.

[jeremyc74]

Originally Posted by Rye

The top finishers in the LMP1 class for this past weekends 24hr Le Mans were all turbo diesels leaving the rest of the classes with NA engines waaaay behind.

You can't even compare race cars. There are restrictions on the various engine types that may or may not be equal. There's also a lot of strategy involved in winning a race, and fuel economy plays a huge role.

This has nothing to do with one car being faster than the other.

[ryanjorunner]

Fact:

Originally Posted by jeremyc74

The area under the power curve is the deciding factor.

[hellrotm]

Originally Posted by Fast kiwi

We can argue all day about Hp vs Tq but with out Tq, Hp doesnt even exsist.. its not a measurable force with out Tq.. its nothing.

Horsepower is derived from torque and rpm.

More horsepower can come about in two ways, make more torque, or make torque at a higher rpm.

Two completely different philosophies to create horsepower.

[Alext]

Torque makes you think you are going fast. It gives you that pinned back in your seat feeling.

Raw engine torque doesn't tell the story until you also consider gearing & revs. Power is often more meaningful because Power = Torque x RPM so it has the revs 'information' built into it already.

A torquier engine will feel better at road speeds as it is able to operate better at lower RPMs.
A higher HP engine will be faster all things considered in its power band.

Consider an F1 engine with 800HP+ and only 250lb ft torque.

As someone said Area under the curve is what you want.

[crzy4135i]

Originally Posted by Sinner

+1 about the quality of design. I had dual 3" exhausts installed on a 5.9 Dodge ram 1500 and there was a noticeable decrease in power, just didn't have enough back pressure. It was loud enough to wake the dead though so there was a plus.

Don't forget the backpressure theory is different for turbo cars. The turbine housing creates plenty of backpressure for the cylinders. After the turbo(s), the less backpressure, the better.

If the total backpressure measured just after the turbos is 7 psi, each component in the exhaust creates a part of that total (the backpressure created by each component adds up to the total). If I had to guess, I'd say the catalytic converters create the most backpressure, then the mufflers, then the diameter and bends of the connecting pipes.

In theory, dual 2.5" diameter pipes are less restrictive than a single 3" but since the piping is the lowest component in the system for creating backpressure.. it would only make a fraction of the difference as catless downpipes or a different muffler design. In other words, I think the 335i guys are stretching it.

[jeremyc74]

Originally Posted by 5soko

sadly, the 135i exhaust does seem to be the culprit in power, from what some seem to think. at the last dyno day, the average was somnewhere around, 15WHP less and about 10 WTQ if i remember correctly. i heard rumors of other engines restrctions and or software restrcitions aka 29.2/v81 but i havent seen it first hand, i can only go by what the dyno showned on that day compared to the 335i's.

FWIW, here is the link from a member

http://www.n54tech.com/forums/showthread.php?t=1318

IMO many exhaust options will come up for the 135i which will be well worth it.

I can believe that the 135i might have a slightly more restrictive exhaust, due to packaging issues, but there's no logical reason in the world why the ECU would be any different.

That link is to a post with a link back to this forum, with one comment about speculation by one tuner on one car. It's hardly anything significant.

I'm willing to bet that an aftermarket exhaust on the 135 will take care of the issue, and power differences between the two cars (if there really are any) will narrow to the point of insignificance. The dual setup has a therotical advantage, but in the real world it comes down to the law of diminishing returns.

[Mr OT]

Food For Thought

Hp = (rpm*torque)/5,250

Rasing either the rotational shaft speed or increasing the power (lb-ft) will result in greater Horsepower.

That is why a Formula 1 engine revs at 20,000 rpm and has over 900 Hp... it only has 240 lb-ft!!!!!!!!!

And yes I am an engineer

[mistermojorizin]

another factor is where you make your torque. if you make your torque in the topend your quarter mile is better than if you make torque at low rpms. As long as you have enough torque to get you going, its an HP game after that (unless you wanna race uphill or tow something). that's why the ferrari engines are modestly torquy (that's all you need really). but, in real life you're not always in the high rpms like on the track, so you need both, like a corvette engine (one of the best v8's out there). but for all out acceleration, you will always be limited by HP. you could make instant torque at 0rpm like an electric motor but you won't be fast, unless you can pump out the hp and torque at the top of the rpm band.

[Spook]

The 135 is still a tenth or so faster to 60 and the quarter. If there is a small bhp difference based on packaging why does this matter?

[TazioNYC]

I wonder if this issue is why BMW claims their performance exhaust is good for 10-15HP

[SAM_702]

HP gives the car top speed. Torque gives the car acceleration. NASCARS run in oval laps, HP is the factor there for top speed. F1 tracks have curves/turns, acceleration rules there.

The more you have of both HP and Torque, the higher the perfomance.

[jeremyc74]

Originally Posted by SAM_702

HP gives the car top speed. Torque gives the car acceleration.

No. You can't even begin to discuss acceleration or top speed without bringing gearing into the equation.

The force that makes a car move is torque at the wheels. That torque can be achieved with a high Hp, high revving engine with low torque, or a low revving engine with lots of torque. With the proper gearing they can each be equally as fast.