Here's the resullts of the 4th gear pulls.

88.3 WHP @ 5300 RPM
103 FtLb @ 3700 RPM

A/F 14.3/14.4 all the way through.

Regan

Modified by voxwagen88 at 1:35 PM 6-3-2006

Flipping through VWSport Tuning, I came across this.

The Caption reads
"The stock Fox exhaust system strangles the engine above 5000 RPM. An aftermarket sport exhaust will yield a 7-hp peak gain and a 14-hp gain at 5500 RPM."

True, but isn't that at the flywheel.

Nice. I'd love to wave the wand over your fuel system. I am sure I could find a few ponies you didn't know about.

"And in two years he made the cover of Time
The albino priest with the psychic mind..."

Richard Wurmbrand Centennial

She seems healthy though. A bit rich? At this level I do not find myself saying"I need more fuel!"

Quote, originally posted by voxwagen88 »

Flipping through VWSport Tuning, I came across this. The Caption reads "The stock Fox exhaust system strangles the engine above 5000 RPM. An aftermarket sport exhaust will yield a 7-hp peak gain and a 14-hp gain at 5500 RPM."

And remember, a Fox is quite a bit lighter than a GTI, therefore it doesn't need an equivalent amount of power to deliver equivalent performance. (For example, the 1976 Rabbit, with 1.6L and 73 HP, matched the acceleration of the 1986 GTI, with 1.8L and 102 HP. Why? Lighter weight, and better gearing!)

GCF - It's Wimblebot approved!

WÄGENWERKS

"i'd rather be judged by 12 people, than carried out by 6"

By way of explainawaytion
The numbers are from a different dyno. With the PSA 5 speed. The big numbers were a second gear pull. The lower numbers generated by run 002 are from a third gear pull and are helpful in guessing what the (lower) 4th gear numbers might have been.

I found I tended to drive the car very hard when it was stock. I felt I had to to keep up. My wife however tended to shift much lower. Working with the torque band rather than the horse power band. She got much better gas mileage.

With the TT exhaust it was much more willing to stretch to 5K rpm.

Now I still like to drive it hard from time to time. But because it is fun, not just to get the car out of its own way.

Modified by voxwagen88 at 9:45 PM 6-4-2006

Modified by voxwagen88 at 11:24 AM 6-28-2009

I wouldn't call it 'rich' unless you were getting down to like 12:1 A/F.

Isn't stoichiometric 14.1:1? If that's the right number, 14.3/14.4 would actually be lean... Or is it 14.7:1? Can't remember off-hand. If stoichio is 14.7, then your 14.3 should be just about rich enough to get you near max power. Maybe you might even want to get down to 13.9...

BTW, I thought most folks did their pulls on the Dyno in 3rd. Why did you do it in 4th?

Modified by snowfox at 10:13 AM 6-5-2006

Quote, originally posted by kerensky »

It's a direct swap. Just be sure to get the 5 speed linkage, as the two are different. And replace the bushings in the new linkage while you've got it apart. And a new clutch/CV joints/bearings/brake rotors/engine swap/paint job/interior refresh, because, you know, while you're in there you might as well.

A-ha! I thought my first guess of 14.1 sounded a little off...

Quote, originally posted by kerensky »

It's a direct swap. Just be sure to get the 5 speed linkage, as the two are different. And replace the bushings in the new linkage while you've got it apart. And a new clutch/CV joints/bearings/brake rotors/engine swap/paint job/interior refresh, because, you know, while you're in there you might as well.

My understanding is that you want to make the measurement in the gear closest to 1:1 in order to limit the torque multiplying effects of the lower gear. Second or third gear pulls tend to produce smoother curves and more flatttering numbers so they are popular.

It probably doesn't matter that much which gear the pull is done in as long as you are comparing it to one done is a similar gear. And of course these were done in different gears with a different set of gears so it quickly becomes apples and oranges with lots of room to speculate.

I'm mostly pleased the numbers are bigger. At least that would suggest it is going in the right direction.

Power on the lean side.
Regan

Aaaaahhhh... I've never actually messed with getting on a Dyno, so the gear selection thing is nothing I've ever had to deal with. Doing it at or as near as possible to 1:1 gearing makes good sense though. Thanks.

Quote, originally posted by kerensky »

It's a direct swap. Just be sure to get the 5 speed linkage, as the two are different. And replace the bushings in the new linkage while you've got it apart. And a new clutch/CV joints/bearings/brake rotors/engine swap/paint job/interior refresh, because, you know, while you're in there you might as well.

From all the tuning stuff i've read a 13.5 to 13.9 AF is the place to be on a NA motor.

Adjust the CIS-E a bit and im sure you'd see over 90whp.