sakimano

So maybe an update? Since getting the downpipes installed, I have done a few test launches etc. to see how the car is progressing. I use a GTECH PRO RR or SS (I have both for some reason) to check 60 foot times and 0-60mph as well as some of the 1/4 mile intervals (330', 1/8th etc.)

It's tough to find a long straight flat road, so I don't bother looking much at the 1/8th mile and up stuff, but I pay attention to the 60', 330' and 60mph stuff.

I did some launches on a road near my house back in November and used my GTECH to measure them. I have always found it hard to get below a 1.97-2.0 second 60 foot on the GTECH. I have NEVER been below 1.95...let alone 1.8X. I imagine it's because you're never launching on a prepped track, so it makes sense. When I was at the dragstrip, I was pretty much always 1.92-1.95 with a few outliers above and below. I imagine if I took the GTECH to the dragstrip it would be pretty much spot on. Here's a good gtech quarter mile run I did a year ago...and you can see the 2.0 60 foot. it was almost always 2.0. This was bone stock by the way, a couple of weeks before getting JHMified, on a nice cold day (a couple below 0 degrees C, 25-30 fahrenheit)



Then, from November when I had all of the same mods as I do today (LWCP, LWFR, snub, FI 2.5 x, JHM intake spacers) except piggies vs. 2.5 catless. I don't remember the weight of the car back then. Not dissimilar to where it stands right now give or take 10-20lbs.

first a couple of 60' times on piggies (1.99, 2.0)



then a couple of 0-60mph times on piggies (4.90, 4.75...I've done a bunch on piggies/tune/catback and they were always in that range, more towards 4.85-4.90)




So...since then I've had the catless 2.5" downpipes to replace the piggies. Here are the February 8th times
60' times with 2.5" catless dps (1.89, 1.89)



0-60mph times with 2.5" catless dps (4.36, 4.36)Those two 4.36 aren't a misprint or an accidental duplication...they were 4.363 and 4.360. There was also a 4.49 second time. Yesterday I was checking something and did a couple of launches. One time was 4.39. The other was 4.24.






That's a pretty solid improvement. Granted it could be that

a) it's colder in Feb...it was ****ing freezing up here (maybe that's worth a tenth?)
b) the car may be a hair lighter, since I don't remember exactly what it weighed then (although tonight I had a full tank to the brim, so may have been heavier)
c) I just launched better? This is a definite possibility as I have had a little help in the past couple of months on 'technique'. (maybe worth another tenth)
d) the downpipes being 2.5 catless are a definite gamechanger (maybe another 1 or 2 tenths).


Still, I think the results are pretty compelling. I'll be the first to tell someone with a gtech to back it up on a certified dragstrip, so I don't mind if any of you want to do the same to me. Just know that I will once things thaw out around here!

cheeba

As you well know, trap speeds give the best indicator of power since it minimizes the huge variable of the launch; but, those are some damn good times! Here's my favourite bench-racing measurement: VAG-COM Butt Dyno

Technically, the Butt Dyno will give results that are more real-world accurate than a dynamometer since it accounts for air resistance, which is a huge variable affecting a vehicle's acceleration. Either way, like a dyno or trap speeds, it's an excellent way to plot progress on your specific vehicle. I've got to say that I'm impressed with the kinds of numbers the B6/7 S4s are putting down with relatively few mod's!

sakimano

thanks Cheeba. The butt dyno is neat. I use logs in a similar while different way. Same concept. The key is though that you shouldn't share them with anyone...because then it turns into a ****-show as guys log downhill to say their parts are better etc. That's what happened with FATS in the B5 worls.

As for the 4.2 Audis, It's a tough platform to mod because it's different to other Audis, and the Audi tuning scene frankly isn't very good at dealing with normally aspirated cars.

JHM has had some success because the principals of the firm came from a long history of racing and developing power parts for normally aspirated platforms.

This formula they follow is just what they (and everyone in the NA scene) has done for decades. It's just funny that the other Audi scene tuners never really gave it the old college try. The BMW world for example has a long history of high revving NA motors. Guess what? Their aftermarket is excellent and the parts add hp. The difference? Audi suddenly went for displacement vs. turbos during the hp wars of the 2000s, while BMW tuning has been NA for decades.

Funny enough BMW recently switched to being almost 100% turbos on their performance variant models...quite an about face for a company that didn't use a turbo for decades...to one that depends on them for almost all of their performance success. The tuning market is great for the turbos because to be honest even a bad tuner will make reasonable power on a turbo car. Safe power? That's another story!

sakimano

not so stock here....this was today on the way back from Detroit. Helped (stretch) JHM install a supercharger on a customer's car. It's pretty badass.

This is my car in the tunnel, struggling to stay under 30mph and to not annoy Canada Customs

m4rkenyux

nice car.. i always love S4 ..

sakimano

^^Thanks.

I thought an update was in order.

First...JHM updated my tune with something special. They have (somehow) built launch control (they call it JHM Launch Assist) right into the tune. Pretty incredible.

Here are a couple of videos.





It works quite well. I wanted to test it vs. my old quarter mile times/launches, so I went to the Cayuga dragstrip with the updated downpipes setup and new tune in April. My previous best 60 foot time out of about 40 dragstrip slips in this car was 1.89, with second best being 1.90. With JHM launch assist, I rattled off 5 different 1.8x 60 foot times, with the best being 1.82. My previous best quarter mile time was 13.21.

Here's my new best thanks to JHM Launch assist and JHM 2.5" downpipes.

sakimano

Made a couple of cosmetic changes to the rear end of the car.

1. added JHMotorsports plate frame
2. blacked out rear valence with plasti-dip (in the spray can version)


Before



After




I also cleaned my wheels for a change. It's amazing what a quality wheel cleaner (P21S wheel gel or Sonax Full Effect, both bought from eshine.ca with the sponsor deal they give us) plus a pressure washer can do. I didn't even have to touch the wheels.

sakimano

Just thought I'd bring some closure to the thread...the car was sold to a lucky new owner.

It was one of the fastest b6/7 S4s and ran awesome for 4 years for me. I will start a new thread with the new car in it...

buddysnack

RIP little buddy. You were the meanest sounding S4 I ever met....

alexander_tromp

definitely go for the carbon fibre spoiler...how about the colour? u gonna touch that?